Add license

- No specular on surfaces facing away from the light source
- Transform the light direction to view space to ensure that all
  lighting calculations happen in a consistent coordinate space.
- Other lighting tweaks

.gitattributes

@@ -0,0 +1,2 @@
+assets/models/* filter=lfs diff=lfs merge=lfs -text
+assets/exr/* filter=lfs diff=lfs merge=lfs -text

.pre-commit-config.yaml

@@ -0,0 +1,11 @@
+repos:
+  - repo: https://github.com/pre-commit/pre-commit-hooks
+    rev: v4.6.0
+    hooks:
+      - id: trailing-whitespace
+        files: "\\.rs$"
+      - id: end-of-file-fixer
+        files: "\\.rs$"
+      - id: mixed-line-ending
+        args: [--fix=lf]
+        files: "\\.rs$"

Cargo.toml

@@ -6,5 +6,6 @@ members = [
     "asset",
     "game",
     "ecs",
-    "engine"
+    "engine",
+    "physics", "app",
 ]

LICENSE

@@ -0,0 +1,661 @@
+                    GNU AFFERO GENERAL PUBLIC LICENSE
+                       Version 3, 19 November 2007
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+later version.
+
+  15. Disclaimer of Warranty.
+
+  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
+APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
+HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
+OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
+IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+  16. Limitation of Liability.
+
+  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+  17. Interpretation of Sections 15 and 16.
+
+  If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Affero General Public License as published
+    by the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Affero General Public License for more details.
+
+    You should have received a copy of the GNU Affero General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+  If your software can interact with users remotely through a computer
+network, you should also make sure that it provides a way for users to
+get its source.  For example, if your program is a web application, its
+interface could display a "Source" link that leads users to an archive
+of the code.  There are many ways you could offer source, and different
+solutions will be better for different programs; see section 13 for the
+specific requirements.
+
+  You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU AGPL, see
+<https://www.gnu.org/licenses/>.

app/Cargo.toml

@@ -0,0 +1,16 @@
+[package]
+name = "raidillon_app"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+raidillon_engine = { path = "../engine" }
+raidillon_platform = { path = "../platform" }
+raidillon_assets = { path = "../asset" }
+raidillon_ecs = { path = "../ecs" }
+raidillon_physics = { path = "../physics" }
+raidillon_glium = { path = "../glium_platform", optional = true }
+raidillon_core = { path = "../core" }
+
+[features]
+glium = ["raidillon_glium"]

app/src/lib.rs

@@ -0,0 +1,45 @@
+pub mod prelude;
+
+pub use prelude::*;
+
+pub struct App {
+    pub engine: Option<Engine>,
+}
+
+impl App {
+    pub fn new() -> Self {
+        let engine = Engine::new();
+        Self { engine: Some(engine) }
+    }
+
+    pub fn add_system<S: System + Default + 'static>(&mut self) -> &mut Self {
+        self.engine.as_mut().unwrap().system_manager.add::<S>();
+        self
+    }
+
+    pub fn add_scene(&mut self, id: SceneID, scene: Scene) -> &mut Self {
+        self.engine.as_mut().unwrap().scene_manager.add_scene(id, scene);
+        self
+    }
+
+    pub fn set_active_scene(&mut self, id: SceneID) -> &mut Self {
+        self.engine.as_mut().unwrap().scene_manager.set_active_scene(id);
+        self
+    }
+
+    pub fn run(&mut self, title: String, width: u32, height: u32) {
+        #[cfg(feature = "glium")]
+        {
+            let platform = GliumPlatform::initialize(
+                self.engine.take().unwrap(),
+                title,
+                width,
+                height,
+            );
+            platform.run();
+        }
+
+        #[cfg(not(any(feature = "glium")))]
+        compile_error!("No platform feature enabled.");
+    }
+}

app/src/prelude.rs

@@ -0,0 +1,47 @@
+pub use raidillon_engine::{
+    Engine,
+    system::System,
+    EngineResources,
+    InputState,
+    system::SystemContext,
+};
+
+pub use raidillon_platform::{
+    Platform,
+    Camera,
+    PlatformContext,
+    TimeContext,
+    DebugWireframes,
+    DebugWireframesRef,
+    DebugWireframeVertex,
+    settings::{Settings, WindowMode},
+};
+
+pub use raidillon_assets::{
+    ModelManagerRef,
+    model_path,
+};
+
+pub use raidillon_ecs::{
+    components::{
+        CameraMode,
+        CharacterBodyComponent,
+        ModelHandle,
+        RigidBodyComponent,
+        Transform,
+    },
+};
+
+pub use raidillon_physics::Physics;
+
+pub use raidillon_core::{
+    scene::{Scene, SceneID},
+    EguiQueue,
+    engine::EngineTrait,
+};
+
+#[cfg(feature = "glium")]
+pub use raidillon_glium::{
+    GliumPlatform,
+    RenderingSystem,
+};

assets/shaders/debug_wireframe.frag

@@ -0,0 +1,9 @@
+#version 330 core
+
+in vec4 v_color;
+
+out vec4 frag_color;
+
+void main() {
+    frag_color = v_color;
+}

assets/shaders/debug_wireframe.vert

@@ -0,0 +1,14 @@
+#version 330 core
+
+in vec3 position;
+in vec4 color;
+
+uniform mat4 view;
+uniform mat4 projection;
+
+out vec4 v_color;
+
+void main() {
+    v_color = color;
+    gl_Position = projection * view * vec4(position, 1.0);
+}

assets/shaders/gl_textured.frag

@@ -6,28 +6,37 @@ in  vec3 v_position;
 
 out vec4 frag_color;
 
-uniform vec3 u_light;
+uniform vec3 u_light;      // direction TO the light (normalized)
 uniform sampler2D tex;
-uniform vec3 color; // base colour factor (acts as solid colour when no texture)
+uniform vec3 color;        // base colour factor (acts as solid colour when no texture)
 
 void main() {
     // Combine base texture (or constant white) with colour factor supplied by CPU.
     vec3 base_col = texture(tex, v_tex).rgb * color;
 
-    vec3 ambient_color  = base_col * 0.2;
-    vec3 diffuse_color  = base_col * 0.6;
-    vec3 specular_color = vec3(1.0);
+    vec3 N = normalize(v_normal);
+    vec3 L = normalize(u_light);
 
-    // u_light is the direction **from the light towards the fragment**.
-    float diffuse = max(dot(normalize(v_normal), normalize(u_light)), 0.0);
+    // Classic Blinn-Phong lighting
+    // Ambient: always present
+    vec3 ambient = base_col * 0.15;
 
-    vec3 camera_dir = normalize(-v_position);
-    vec3 half_dir   = normalize(normalize(u_light) + camera_dir);
-    float specular  = pow(max(dot(half_dir, normalize(v_normal)), 0.0), 16.0);
+    // Diffuse: N dot L, clamped
+    float NdotL = max(dot(N, L), 0.0);
+    vec3 diffuse = base_col * NdotL * 0.7;
 
-    vec3 result = ambient_color + diffuse * diffuse_color + specular * specular_color;
+    // Specular: only on surfaces facing the light (NdotL > 0)
+    float specular = 0.0;
+    if (NdotL > 0.0) {
+        vec3 V = normalize(-v_position);         // view direction (camera at origin in view space)
+        vec3 H = normalize(L + V);               // half-vector
+        float NdotH = max(dot(N, H), 0.0);
+        specular = pow(NdotH, 32.0) * 0.5;       // tighter highlight, moderated intensity
+    }
 
-    // Convert from linear to sRGB for display (approximate γ-correction)
+    vec3 result = ambient + diffuse + vec3(specular);
+
+    // Convert from linear to sRGB for display (approximate gamma correction)
     result = pow(result, vec3(1.0 / 2.2));
 
     frag_color = vec4(result, 1.0);

assets/shaders/skybox.frag

@@ -9,14 +9,19 @@ uniform sampler2D equirect;
 const vec2 inv_atan = vec2(0.15915494309, 0.31830988618);
 
 vec2 sample_spherical_map(vec3 v) {
-    vec2 uv = vec2(atan(v.z, v.x), asin(v.y));
+    vec2 uv = vec2(atan(v.z, v.x), asin(clamp(v.y, -1.0, 1.0)));
     uv *= inv_atan;
     uv += 0.5;
+    uv.x = fract(uv.x);
     return uv;
 }
 
 void main() {
     vec2 uv = sample_spherical_map(normalize(direction));
+    uv.y = 1.0 - uv.y;
+    vec2 size = vec2(textureSize(equirect, 0));
+    float epsY = 0.5 / max(size.y, 1.0);
+    uv.y = clamp(uv.y, epsY, 1.0 - epsY);
     vec3 color = texture(equirect, uv).rgb;
     frag_color = vec4(color, 1.0);
 }

core/Cargo.toml

@@ -8,4 +8,4 @@ hecs = "0.10.5"
 indexmap = "2.10.0"
 raidillon_assets = { path = "../asset" }
 winit = "0.30.12"
-imgui = "0.12.0"
+egui = "0.33.2"

core/src/context.rs

@@ -1,13 +0,0 @@
-use std::cell::RefCell;
-use std::rc::Rc;
-use std::sync::Arc;
-use winit::event::Event;
-use raidillon_assets::{ModelManagerRef, ModelManager};
-
-#[derive(Clone)]
-pub struct PlatformContext {
-    pub current_event: Event<()>,
-    pub asset_manager: ModelManagerRef,
-    pub frame_width: f32,
-    pub frame_height: f32,
-}

core/src/debug_ui.rs

@@ -1,40 +0,0 @@
-pub enum UICommand {
-    Text(String),
-    Separator,
-}
-
-pub struct DebugUIBuffer {
-    cmds: Vec<UICommand>,
-}
-
-impl DebugUIBuffer {
-    pub fn new() -> DebugUIBuffer {
-        DebugUIBuffer { cmds: vec![] }
-    }
-
-    // Commands
-    pub fn text(&mut self, text: String) {
-        self.cmds.push(UICommand::Text(text));
-    }
-
-    pub fn separator(&mut self) {
-        self.cmds.push(UICommand::Separator);
-    }
-
-    pub fn write_buffer(&self, ui: &imgui::Ui) {
-        for cmd in &self.cmds {
-            match cmd {
-                UICommand::Text(s) => {
-                    ui.text(s);
-                }
-                UICommand::Separator => {
-                    ui.separator();
-                }
-            }
-        }
-    }
-
-    pub fn reset_buffer(&mut self) {
-        self.cmds = vec![];
-    }
-}

core/src/egui_queue.rs

@@ -0,0 +1,22 @@
+pub struct EguiQueue {
+    pub queue_vec: Vec<Box<dyn FnOnce(&egui::Context) + Send>>,
+}
+
+impl EguiQueue {
+    pub fn new() -> Self {
+        Self { queue_vec: Vec::new() }
+    }
+
+    pub fn queue(&mut self, func: impl FnOnce(&egui::Context) + Send + 'static) {
+        self.queue_vec.push(Box::new(func));
+    }
+
+    pub fn clear(&mut self) {
+        self.queue_vec.clear()
+    }
+
+    pub fn run(&mut self, ctx: &egui::Context) {
+        self.queue_vec.drain(..).for_each(|func| func(ctx));
+        self.clear();
+    }
+}

core/src/engine.rs

@@ -1,16 +1,12 @@
-use std::cell::RefCell;
-use std::rc::Rc;
-use crate::context::PlatformContext;
-use crate::DebugUIBuffer;
 use crate::scene::Scene;
 
 pub trait EngineTrait {
+    type PlatformCtx: Clone;
     fn new() -> Self;
-    fn initialize(&mut self, platform_context: PlatformContext);
-    fn update(&mut self, platform_context: PlatformContext);
-    fn handle_event(&mut self, platform_context: PlatformContext);
+    fn initialize(&mut self, platform_context: Self::PlatformCtx);
+    fn frame_update(&mut self, platform_context: Self::PlatformCtx);
+    fn fixed_update(&mut self, platform_context: Self::PlatformCtx);
+    fn handle_event(&mut self, platform_context: Self::PlatformCtx);
     fn current_scene_mut(&mut self) -> &mut Scene;
-    fn get_debug_ui_buffer(&self) -> Rc<RefCell<DebugUIBuffer>>;
-    fn reset_debug_ui_buffer(&mut self);
-    fn scene_and_debug_ui_buffer_mut(&mut self) -> (&mut Scene, Rc<RefCell<DebugUIBuffer>>);
+    fn current_scene(&self) -> &Scene;
 }

core/src/lib.rs

@@ -1,5 +1,7 @@
 pub mod engine;
+pub mod time;
+pub mod utils;
 pub mod scene;
-pub mod context;
-pub mod debug_ui;
-pub use debug_ui::*;
+mod egui_queue;
+
+pub use egui_queue::EguiQueue;

core/src/scene.rs

@@ -1,20 +1,29 @@
 use std::collections::HashMap;
 use std::path::{Path, PathBuf};
+use crate::{define_typemap};
 
 pub struct Scene {
     pub title: String,
     pub world: hecs::World,
     pub skybox_texture_path: Option<PathBuf>,
+    pub resources: SceneResources,
 }
 
+define_typemap!(SceneResources,);
+
 impl Scene {
     pub fn new(title: String, skybox_texture_path: Option<PathBuf>) -> Self {
-        Self {
+        let mut s = Self {
             title,
             world: hecs::World::new(),
             skybox_texture_path,
-        }
+            resources: SceneResources::new(),
+        };
+        s.load_default_resources();
+        s
     }
+
+    pub fn load_default_resources(&mut self) {}
 }
 
 impl Scene {}
@@ -31,7 +40,7 @@ impl AsMut<Scene> for Scene {
     }
 }
 
-type SceneID = &'static str;
+pub type SceneID = &'static str;
 
 pub struct SceneManager {
     scenes: HashMap<SceneID, Scene>,

core/src/time.rs

@@ -0,0 +1,144 @@
+use std::thread;
+use std::time::{Duration, Instant};
+
+#[derive(Clone, Debug)]
+pub struct Config {
+    pub target_frame_hz: Option<f64>,
+    pub target_update_hz: f64,
+    pub max_updates_per_frame: u32,
+    pub max_accumulated_steps: u32,
+    pub sleep_tolerance: Duration,
+}
+
+impl Default for Config {
+    fn default() -> Self {
+        Self {
+            target_frame_hz: Some(144.0),
+            target_update_hz: 60.0,
+            max_updates_per_frame: 5,
+            max_accumulated_steps: 8,
+            sleep_tolerance: Duration::from_micros(500),
+        }
+    }
+}
+
+#[derive(Debug)]
+pub struct Time {
+    cfg: Config,
+    last_instant: Instant,
+    next_frame_due: Instant,
+    frame_interval: Option<Duration>,
+    fixed_dt: Duration,
+
+    // tracking
+    frame_dt: Duration,
+    accumulator: Duration,
+
+    // counters
+    pub frame_count: u64,
+    pub update_count: u64,
+}
+
+pub struct TickPlan {
+    /// How many fixed updates to run this frame
+    pub updates: u32,
+    /// Interpolation factor for rendering between previous/next sim states
+    pub alpha: f32,
+    /// Measured last frame delta (seconds)
+    pub frame_dt: f32,
+    /// Fixed timestep (seconds)
+    pub fixed_dt: f32,
+}
+
+impl Time {
+    pub fn new(cfg: Config) -> Self {
+        let now = Instant::now();
+        let frame_interval = cfg.target_frame_hz.map(|hz| Duration::from_secs_f64(1.0 / hz));
+        let fixed_dt = Duration::from_secs_f64(1.0 / cfg.target_update_hz);
+        Self {
+            cfg,
+            last_instant: now,
+            next_frame_due: now,
+            frame_interval,
+            fixed_dt,
+            frame_dt: Duration::ZERO,
+            accumulator: Duration::ZERO,
+            frame_count: 0,
+            update_count: 0,
+        }
+    }
+
+    pub fn reconfigure(&mut self, cfg: Config) {
+        self.cfg = cfg.clone();
+        self.frame_interval = cfg.target_frame_hz.map(|hz| Duration::from_secs_f64(1.0 / hz));
+        self.fixed_dt = Duration::from_secs_f64(1.0 / cfg.target_update_hz);
+    }
+
+    pub fn begin_frame_blocking(&mut self) -> TickPlan {
+        // 1) If there's a frame cap, block until next frame deadline
+        if let Some(interval) = self.frame_interval {
+            let mut now = Instant::now();
+            if now < self.next_frame_due {
+                // Sleep most of the remainder, then spin the last tiny bit for precision
+                let total_remaining = self.next_frame_due - now;
+                if total_remaining > self.cfg.sleep_tolerance {
+                    let sleep_for = total_remaining - self.cfg.sleep_tolerance;
+                    thread::sleep(sleep_for);
+                }
+                // Short spin-wait for precision
+                while Instant::now() < self.next_frame_due {
+                    std::hint::spin_loop();
+                }
+                now = self.next_frame_due;
+            }
+            self.next_frame_due = self.next_frame_due + interval;
+            // In case we fell far behind (e.g., debugger pause), resync.
+            if self.next_frame_due < now {
+                self.next_frame_due = now + interval;
+            }
+        }
+
+        // 2) Measure frame dt
+        let now = Instant::now();
+        self.frame_dt = now.saturating_duration_since(self.last_instant);
+        self.last_instant = now;
+        self.frame_count += 1;
+
+        // 3) Accumulate for fixed updates
+        self.accumulator += self.frame_dt;
+
+        // Clamp accumulator to avoid doing a huge number of updates after a stall
+        let max_accumulated = self.fixed_dt * self.cfg.max_accumulated_steps;
+        if self.accumulator > max_accumulated {
+            self.accumulator = max_accumulated;
+        }
+
+        // 4) Determine how many updates to run this frame
+        let mut updates = 0u32;
+        while self.accumulator >= self.fixed_dt && updates < self.cfg.max_updates_per_frame {
+            self.accumulator -= self.fixed_dt;
+            updates += 1;
+            self.update_count += 1;
+        }
+
+        // 5) Compute interpolation factor for rendering (0..1)
+        let alpha = if self.fixed_dt.is_zero() {
+            1.0
+        } else {
+            (self.accumulator.as_secs_f32() / self.fixed_dt.as_secs_f32()).clamp(0.0, 1.0)
+        };
+
+        TickPlan {
+            updates,
+            alpha,
+            frame_dt: self.frame_dt.as_secs_f32(),
+            fixed_dt: self.fixed_dt.as_secs_f32(),
+        }
+    }
+
+    pub fn frame_dt_seconds(&self) -> f32 { self.frame_dt.as_secs_f32() }
+    pub fn fixed_dt_seconds(&self) -> f32 { self.fixed_dt.as_secs_f32() }
+    pub fn alpha(&self) -> f32 {
+        if self.fixed_dt.is_zero() { 1.0 } else { (self.accumulator.as_secs_f32() / self.fixed_dt.as_secs_f32()).clamp(0.0, 1.0) }
+    }
+}

core/src/utils/managers.rs

@@ -0,0 +1,44 @@
+/// Unused as of now.
+#[macro_export]
+macro_rules! create_manager {
+    ($manager_name:ident, $trait_name:ident) => {
+        pub struct $manager_name {
+            systems: ::indexmap::IndexMap<::std::any::TypeId, Box<dyn $trait_name>>,
+        }
+
+        impl $manager_name {
+            pub fn new() -> Self {
+                Self {
+                    systems: ::indexmap::IndexMap::default(),
+                }
+            }
+
+            pub fn add<S: $trait_name + Default + 'static>(&mut self) {
+                self.systems
+                    .insert(::std::any::TypeId::of::<S>(), Box::new(S::default()));
+            }
+
+            pub fn remove<S: 'static>(&mut self) {
+                self.systems.shift_remove(&::std::any::TypeId::of::<S>());
+            }
+
+            pub fn for_each_value<F>(&self, mut f: F)
+            where
+                F: FnMut(&dyn $trait_name),
+            {
+                for value in self.systems.values() {
+                    f(value.as_ref());
+                }
+            }
+
+            pub fn for_each_value_mut<F>(&mut self, mut f: F)
+            where
+                F: FnMut(&mut dyn $trait_name),
+            {
+                for value in self.systems.values_mut() {
+                    f(value.as_mut());
+                }
+            }
+        }
+    };
+}

core/src/utils/mod.rs

@@ -0,0 +1,2 @@
+pub mod typemap;
+mod managers;

core/src/utils/typemap.rs

@@ -0,0 +1,544 @@
+#[macro_export]
+macro_rules! define_typemap {
+    ($name:ident, $($trait_bound:tt)*) => {
+        pub struct $name {
+            map: std::collections::HashMap<std::any::TypeId, Box<dyn std::any::Any>>,
+        }
+
+        impl $name {
+            pub fn new() -> Self {
+                Self { map: std::collections::HashMap::new() }
+            }
+
+            pub fn insert<T>(&mut self, value: T) -> Option<Box<T>>
+            where
+                T: std::any::Any + 'static + $($trait_bound)*,
+            {
+                let type_id = std::any::TypeId::of::<T>();
+                self.map.insert(type_id, Box::new(value)).and_then(|b| b.downcast().ok())
+            }
+
+            pub fn get<T>(&self) -> Option<&T>
+            where
+                T: std::any::Any + 'static + $($trait_bound)*,
+            {
+                self.map.get(&std::any::TypeId::of::<T>())?.downcast_ref::<T>()
+            }
+
+            pub fn get_mut<T>(&mut self) -> Option<&mut T>
+            where
+                T: std::any::Any + 'static + $($trait_bound)*,
+            {
+                self.map.get_mut(&std::any::TypeId::of::<T>())?.downcast_mut::<T>()
+            }
+
+            pub fn remove<T>(&mut self) -> Option<Box<T>>
+            where
+                T: std::any::Any + 'static + $($trait_bound)*,
+            {
+                self.map.remove(&std::any::TypeId::of::<T>())?.downcast().ok()
+            }
+
+            pub fn len(&self) -> usize { self.map.len() }
+            pub fn is_empty(&self) -> bool { self.map.is_empty() }
+            pub fn clear(&mut self) { self.map.clear(); }
+
+            pub fn contains<T>(&self) -> bool
+            where
+                T: std::any::Any + 'static + $($trait_bound)*,
+            {
+                self.map.contains_key(&std::any::TypeId::of::<T>())
+            }
+
+            // --- tuple-based multi-get API ---
+            pub fn get_many<'a, T>(&'a self) -> Option<<T as __tm_get::GetTuple>::Output<'a>>
+            where
+                T: __tm_get::GetTuple,
+            {
+                <T as __tm_get::GetTuple>::get_from(&self.map)
+            }
+
+            pub fn get_many_mut<'a, T>(&'a mut self) -> Option<<T as __tm_get::GetTupleMut>::Output<'a>>
+            where
+                T: __tm_get::GetTupleMut,
+            {
+                <T as __tm_get::GetTupleMut>::get_from_mut(&mut self.map)
+            }
+        }
+
+        impl Default for $name { fn default() -> Self { Self::new() } }
+
+        // Put helper traits/impls in a private module to avoid name clashes.
+        mod __tm_get {
+            use std::any::{Any, TypeId};
+            use std::collections::HashMap;
+
+            pub trait GetTuple {
+                type Output<'a>;
+                fn get_from<'a>(map: &'a HashMap<TypeId, Box<dyn Any>>) -> Option<Self::Output<'a>>;
+            }
+
+            pub trait GetTupleMut {
+                type Output<'a>;
+                fn get_from_mut<'a>(map: &'a mut HashMap<TypeId, Box<dyn Any>>) -> Option<Self::Output<'a>>;
+            }
+
+            // Manual implementations for arities 1..=8.
+            impl<A> GetTuple for (A,)
+            where
+                A: Any + 'static,
+            {
+                type Output<'a> = (&'a A,);
+                fn get_from<'a>(map: &'a HashMap<TypeId, Box<dyn Any>>) -> Option<Self::Output<'a>> {
+                    let a = map.get(&TypeId::of::<A>())?.downcast_ref::<A>()?;
+                    Some((a,))
+                }
+            }
+
+            impl<A> GetTupleMut for (A,)
+            where
+                A: Any + 'static,
+            {
+                type Output<'a> = (&'a mut A,);
+                fn get_from_mut<'a>(map: &'a mut HashMap<TypeId, Box<dyn Any>>) -> Option<Self::Output<'a>> {
+                    let ptr_a = { map.get_mut(&TypeId::of::<A>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    unsafe {
+                        let a = (&mut *ptr_a).downcast_mut::<A>()?;
+                        Some((a,))
+                    }
+                }
+            }
+
+            impl<A, B> GetTuple for (A, B)
+            where
+                A: Any + 'static,
+                B: Any + 'static,
+            {
+                type Output<'a> = (&'a A, &'a B);
+                fn get_from<'a>(map: &'a HashMap<TypeId, Box<dyn Any>>) -> Option<Self::Output<'a>> {
+                    let ids = [TypeId::of::<A>(), TypeId::of::<B>()];
+                    if ids[0] == ids[1] { return None; }
+                    let a = map.get(&TypeId::of::<A>())?.downcast_ref::<A>()?;
+                    let b = map.get(&TypeId::of::<B>())?.downcast_ref::<B>()?;
+                    Some((a, b))
+                }
+            }
+
+            impl<A, B> GetTupleMut for (A, B)
+            where
+                A: Any + 'static,
+                B: Any + 'static,
+            {
+                type Output<'a> = (&'a mut A, &'a mut B);
+                fn get_from_mut<'a>(map: &'a mut HashMap<TypeId, Box<dyn Any>>) -> Option<Self::Output<'a>> {
+                    let ids = [TypeId::of::<A>(), TypeId::of::<B>()];
+                    if ids[0] == ids[1] { return None; }
+                    let ptr_a = { map.get_mut(&TypeId::of::<A>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    let ptr_b = { map.get_mut(&TypeId::of::<B>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    unsafe {
+                        let a = (&mut *ptr_a).downcast_mut::<A>()?;
+                        let b = (&mut *ptr_b).downcast_mut::<B>()?;
+                        Some((a, b))
+                    }
+                }
+            }
+
+            impl<A, B, C> GetTuple for (A, B, C)
+            where
+                A: Any + 'static,
+                B: Any + 'static,
+                C: Any + 'static,
+            {
+                type Output<'a> = (&'a A, &'a B, &'a C);
+                fn get_from<'a>(map: &'a HashMap<TypeId, Box<dyn Any>>) -> Option<Self::Output<'a>> {
+                    let ids = [TypeId::of::<A>(), TypeId::of::<B>(), TypeId::of::<C>()];
+                    if ids[0] == ids[1] || ids[0] == ids[2] || ids[1] == ids[2] { return None; }
+                    let a = map.get(&TypeId::of::<A>())?.downcast_ref::<A>()?;
+                    let b = map.get(&TypeId::of::<B>())?.downcast_ref::<B>()?;
+                    let c = map.get(&TypeId::of::<C>())?.downcast_ref::<C>()?;
+                    Some((a, b, c))
+                }
+            }
+
+            impl<A, B, C> GetTupleMut for (A, B, C)
+            where
+                A: Any + 'static,
+                B: Any + 'static,
+                C: Any + 'static,
+            {
+                type Output<'a> = (&'a mut A, &'a mut B, &'a mut C);
+                fn get_from_mut<'a>(map: &'a mut HashMap<TypeId, Box<dyn Any>>) -> Option<Self::Output<'a>> {
+                    let ids = [TypeId::of::<A>(), TypeId::of::<B>(), TypeId::of::<C>()];
+                    if ids[0] == ids[1] || ids[0] == ids[2] || ids[1] == ids[2] { return None; }
+                    let ptr_a = { map.get_mut(&TypeId::of::<A>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    let ptr_b = { map.get_mut(&TypeId::of::<B>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    let ptr_c = { map.get_mut(&TypeId::of::<C>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    unsafe {
+                        let a = (&mut *ptr_a).downcast_mut::<A>()?;
+                        let b = (&mut *ptr_b).downcast_mut::<B>()?;
+                        let c = (&mut *ptr_c).downcast_mut::<C>()?;
+                        Some((a, b, c))
+                    }
+                }
+            }
+
+            impl<A, B, C, D> GetTuple for (A, B, C, D)
+            where
+                A: Any + 'static,
+                B: Any + 'static,
+                C: Any + 'static,
+                D: Any + 'static,
+            {
+                type Output<'a> = (&'a A, &'a B, &'a C, &'a D);
+                fn get_from<'a>(map: &'a HashMap<TypeId, Box<dyn Any>>) -> Option<Self::Output<'a>> {
+                    let ids = [TypeId::of::<A>(), TypeId::of::<B>(), TypeId::of::<C>(), TypeId::of::<D>()];
+                    for i in 0..ids.len() { for j in (i+1)..ids.len() { if ids[i] == ids[j] { return None; } } }
+                    let a = map.get(&TypeId::of::<A>())?.downcast_ref::<A>()?;
+                    let b = map.get(&TypeId::of::<B>())?.downcast_ref::<B>()?;
+                    let c = map.get(&TypeId::of::<C>())?.downcast_ref::<C>()?;
+                    let d = map.get(&TypeId::of::<D>())?.downcast_ref::<D>()?;
+                    Some((a, b, c, d))
+                }
+            }
+
+            impl<A, B, C, D> GetTupleMut for (A, B, C, D)
+            where
+                A: Any + 'static,
+                B: Any + 'static,
+                C: Any + 'static,
+                D: Any + 'static,
+            {
+                type Output<'a> = (&'a mut A, &'a mut B, &'a mut C, &'a mut D);
+                fn get_from_mut<'a>(map: &'a mut HashMap<TypeId, Box<dyn Any>>) -> Option<Self::Output<'a>> {
+                    let ids = [TypeId::of::<A>(), TypeId::of::<B>(), TypeId::of::<C>(), TypeId::of::<D>()];
+                    for i in 0..ids.len() { for j in (i+1)..ids.len() { if ids[i] == ids[j] { return None; } } }
+                    let ptr_a = { map.get_mut(&TypeId::of::<A>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    let ptr_b = { map.get_mut(&TypeId::of::<B>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    let ptr_c = { map.get_mut(&TypeId::of::<C>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    let ptr_d = { map.get_mut(&TypeId::of::<D>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    unsafe {
+                        let a = (&mut *ptr_a).downcast_mut::<A>()?;
+                        let b = (&mut *ptr_b).downcast_mut::<B>()?;
+                        let c = (&mut *ptr_c).downcast_mut::<C>()?;
+                        let d = (&mut *ptr_d).downcast_mut::<D>()?;
+                        Some((a, b, c, d))
+                    }
+                }
+            }
+
+            impl<A, B, C, D, E> GetTuple for (A, B, C, D, E)
+            where
+                A: Any + 'static,
+                B: Any + 'static,
+                C: Any + 'static,
+                D: Any + 'static,
+                E: Any + 'static,
+            {
+                type Output<'a> = (&'a A, &'a B, &'a C, &'a D, &'a E);
+                fn get_from<'a>(map: &'a HashMap<TypeId, Box<dyn Any>>) -> Option<Self::Output<'a>> {
+                    let ids = [TypeId::of::<A>(), TypeId::of::<B>(), TypeId::of::<C>(), TypeId::of::<D>(), TypeId::of::<E>()];
+                    for i in 0..ids.len() { for j in (i+1)..ids.len() { if ids[i] == ids[j] { return None; } } }
+                    let a = map.get(&TypeId::of::<A>())?.downcast_ref::<A>()?;
+                    let b = map.get(&TypeId::of::<B>())?.downcast_ref::<B>()?;
+                    let c = map.get(&TypeId::of::<C>())?.downcast_ref::<C>()?;
+                    let d = map.get(&TypeId::of::<D>())?.downcast_ref::<D>()?;
+                    let e = map.get(&TypeId::of::<E>())?.downcast_ref::<E>()?;
+                    Some((a, b, c, d, e))
+                }
+            }
+
+            impl<A, B, C, D, E> GetTupleMut for (A, B, C, D, E)
+            where
+                A: Any + 'static,
+                B: Any + 'static,
+                C: Any + 'static,
+                D: Any + 'static,
+                E: Any + 'static,
+            {
+                type Output<'a> = (&'a mut A, &'a mut B, &'a mut C, &'a mut D, &'a mut E);
+                fn get_from_mut<'a>(map: &'a mut HashMap<TypeId, Box<dyn Any>>) -> Option<Self::Output<'a>> {
+                    let ids = [TypeId::of::<A>(), TypeId::of::<B>(), TypeId::of::<C>(), TypeId::of::<D>(), TypeId::of::<E>()];
+                    for i in 0..ids.len() { for j in (i+1)..ids.len() { if ids[i] == ids[j] { return None; } } }
+                    let ptr_a = { map.get_mut(&TypeId::of::<A>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    let ptr_b = { map.get_mut(&TypeId::of::<B>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    let ptr_c = { map.get_mut(&TypeId::of::<C>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    let ptr_d = { map.get_mut(&TypeId::of::<D>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    let ptr_e = { map.get_mut(&TypeId::of::<E>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    unsafe {
+                        let a = (&mut *ptr_a).downcast_mut::<A>()?;
+                        let b = (&mut *ptr_b).downcast_mut::<B>()?;
+                        let c = (&mut *ptr_c).downcast_mut::<C>()?;
+                        let d = (&mut *ptr_d).downcast_mut::<D>()?;
+                        let e = (&mut *ptr_e).downcast_mut::<E>()?;
+                        Some((a, b, c, d, e))
+                    }
+                }
+            }
+
+            impl<A, B, C, D, E, F> GetTuple for (A, B, C, D, E, F)
+            where
+                A: Any + 'static,
+                B: Any + 'static,
+                C: Any + 'static,
+                D: Any + 'static,
+                E: Any + 'static,
+                F: Any + 'static,
+            {
+                type Output<'a> = (&'a A, &'a B, &'a C, &'a D, &'a E, &'a F);
+                fn get_from<'a>(map: &'a HashMap<TypeId, Box<dyn Any>>) -> Option<Self::Output<'a>> {
+                    let ids = [TypeId::of::<A>(), TypeId::of::<B>(), TypeId::of::<C>(), TypeId::of::<D>(), TypeId::of::<E>(), TypeId::of::<F>()];
+                    for i in 0..ids.len() { for j in (i+1)..ids.len() { if ids[i] == ids[j] { return None; } } }
+                    let a = map.get(&TypeId::of::<A>())?.downcast_ref::<A>()?;
+                    let b = map.get(&TypeId::of::<B>())?.downcast_ref::<B>()?;
+                    let c = map.get(&TypeId::of::<C>())?.downcast_ref::<C>()?;
+                    let d = map.get(&TypeId::of::<D>())?.downcast_ref::<D>()?;
+                    let e = map.get(&TypeId::of::<E>())?.downcast_ref::<E>()?;
+                    let f = map.get(&TypeId::of::<F>())?.downcast_ref::<F>()?;
+                    Some((a, b, c, d, e, f))
+                }
+            }
+
+            impl<A, B, C, D, E, F> GetTupleMut for (A, B, C, D, E, F)
+            where
+                A: Any + 'static,
+                B: Any + 'static,
+                C: Any + 'static,
+                D: Any + 'static,
+                E: Any + 'static,
+                F: Any + 'static,
+            {
+                type Output<'a> = (&'a mut A, &'a mut B, &'a mut C, &'a mut D, &'a mut E, &'a mut F);
+                fn get_from_mut<'a>(map: &'a mut HashMap<TypeId, Box<dyn Any>>) -> Option<Self::Output<'a>> {
+                    let ids = [TypeId::of::<A>(), TypeId::of::<B>(), TypeId::of::<C>(), TypeId::of::<D>(), TypeId::of::<E>(), TypeId::of::<F>()];
+                    for i in 0..ids.len() { for j in (i+1)..ids.len() { if ids[i] == ids[j] { return None; } } }
+                    let ptr_a = { map.get_mut(&TypeId::of::<A>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    let ptr_b = { map.get_mut(&TypeId::of::<B>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    let ptr_c = { map.get_mut(&TypeId::of::<C>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    let ptr_d = { map.get_mut(&TypeId::of::<D>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    let ptr_e = { map.get_mut(&TypeId::of::<E>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    let ptr_f = { map.get_mut(&TypeId::of::<F>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    unsafe {
+                        let a = (&mut *ptr_a).downcast_mut::<A>()?;
+                        let b = (&mut *ptr_b).downcast_mut::<B>()?;
+                        let c = (&mut *ptr_c).downcast_mut::<C>()?;
+                        let d = (&mut *ptr_d).downcast_mut::<D>()?;
+                        let e = (&mut *ptr_e).downcast_mut::<E>()?;
+                        let f = (&mut *ptr_f).downcast_mut::<F>()?;
+                        Some((a, b, c, d, e, f))
+                    }
+                }
+            }
+
+            impl<A, B, C, D, E, F, G> GetTuple for (A, B, C, D, E, F, G)
+            where
+                A: Any + 'static,
+                B: Any + 'static,
+                C: Any + 'static,
+                D: Any + 'static,
+                E: Any + 'static,
+                F: Any + 'static,
+                G: Any + 'static,
+            {
+                type Output<'a> = (&'a A, &'a B, &'a C, &'a D, &'a E, &'a F, &'a G);
+                fn get_from<'a>(map: &'a HashMap<TypeId, Box<dyn Any>>) -> Option<Self::Output<'a>> {
+                    let ids = [TypeId::of::<A>(), TypeId::of::<B>(), TypeId::of::<C>(), TypeId::of::<D>(), TypeId::of::<E>(), TypeId::of::<F>(), TypeId::of::<G>()];
+                    for i in 0..ids.len() { for j in (i+1)..ids.len() { if ids[i] == ids[j] { return None; } } }
+                    let a = map.get(&TypeId::of::<A>())?.downcast_ref::<A>()?;
+                    let b = map.get(&TypeId::of::<B>())?.downcast_ref::<B>()?;
+                    let c = map.get(&TypeId::of::<C>())?.downcast_ref::<C>()?;
+                    let d = map.get(&TypeId::of::<D>())?.downcast_ref::<D>()?;
+                    let e = map.get(&TypeId::of::<E>())?.downcast_ref::<E>()?;
+                    let f = map.get(&TypeId::of::<F>())?.downcast_ref::<F>()?;
+                    let g = map.get(&TypeId::of::<G>())?.downcast_ref::<G>()?;
+                    Some((a, b, c, d, e, f, g))
+                }
+            }
+
+            impl<A, B, C, D, E, F, G> GetTupleMut for (A, B, C, D, E, F, G)
+            where
+                A: Any + 'static,
+                B: Any + 'static,
+                C: Any + 'static,
+                D: Any + 'static,
+                E: Any + 'static,
+                F: Any + 'static,
+                G: Any + 'static,
+            {
+                type Output<'a> = (&'a mut A, &'a mut B, &'a mut C, &'a mut D, &'a mut E, &'a mut F, &'a mut G);
+                fn get_from_mut<'a>(map: &'a mut HashMap<TypeId, Box<dyn Any>>) -> Option<Self::Output<'a>> {
+                    let ids = [TypeId::of::<A>(), TypeId::of::<B>(), TypeId::of::<C>(), TypeId::of::<D>(), TypeId::of::<E>(), TypeId::of::<F>(), TypeId::of::<G>()];
+                    for i in 0..ids.len() { for j in (i+1)..ids.len() { if ids[i] == ids[j] { return None; } } }
+                    let ptr_a = { map.get_mut(&TypeId::of::<A>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    let ptr_b = { map.get_mut(&TypeId::of::<B>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    let ptr_c = { map.get_mut(&TypeId::of::<C>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    let ptr_d = { map.get_mut(&TypeId::of::<D>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    let ptr_e = { map.get_mut(&TypeId::of::<E>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    let ptr_f = { map.get_mut(&TypeId::of::<F>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    let ptr_g = { map.get_mut(&TypeId::of::<G>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    unsafe {
+                        let a = (&mut *ptr_a).downcast_mut::<A>()?;
+                        let b = (&mut *ptr_b).downcast_mut::<B>()?;
+                        let c = (&mut *ptr_c).downcast_mut::<C>()?;
+                        let d = (&mut *ptr_d).downcast_mut::<D>()?;
+                        let e = (&mut *ptr_e).downcast_mut::<E>()?;
+                        let f = (&mut *ptr_f).downcast_mut::<F>()?;
+                        let g = (&mut *ptr_g).downcast_mut::<G>()?;
+                        Some((a, b, c, d, e, f, g))
+                    }
+                }
+            }
+
+            impl<A, B, C, D, E, F, G, H> GetTuple for (A, B, C, D, E, F, G, H)
+            where
+                A: Any + 'static,
+                B: Any + 'static,
+                C: Any + 'static,
+                D: Any + 'static,
+                E: Any + 'static,
+                F: Any + 'static,
+                G: Any + 'static,
+                H: Any + 'static,
+            {
+                type Output<'a> = (&'a A, &'a B, &'a C, &'a D, &'a E, &'a F, &'a G, &'a H);
+                fn get_from<'a>(map: &'a HashMap<TypeId, Box<dyn Any>>) -> Option<Self::Output<'a>> {
+                    let ids = [TypeId::of::<A>(), TypeId::of::<B>(), TypeId::of::<C>(), TypeId::of::<D>(), TypeId::of::<E>(), TypeId::of::<F>(), TypeId::of::<G>(), TypeId::of::<H>()];
+                    for i in 0..ids.len() { for j in (i+1)..ids.len() { if ids[i] == ids[j] { return None; } } }
+                    let a = map.get(&TypeId::of::<A>())?.downcast_ref::<A>()?;
+                    let b = map.get(&TypeId::of::<B>())?.downcast_ref::<B>()?;
+                    let c = map.get(&TypeId::of::<C>())?.downcast_ref::<C>()?;
+                    let d = map.get(&TypeId::of::<D>())?.downcast_ref::<D>()?;
+                    let e = map.get(&TypeId::of::<E>())?.downcast_ref::<E>()?;
+                    let f = map.get(&TypeId::of::<F>())?.downcast_ref::<F>()?;
+                    let g = map.get(&TypeId::of::<G>())?.downcast_ref::<G>()?;
+                    let h = map.get(&TypeId::of::<H>())?.downcast_ref::<H>()?;
+                    Some((a, b, c, d, e, f, g, h))
+                }
+            }
+
+            impl<A, B, C, D, E, F, G, H> GetTupleMut for (A, B, C, D, E, F, G, H)
+            where
+                A: Any + 'static,
+                B: Any + 'static,
+                C: Any + 'static,
+                D: Any + 'static,
+                E: Any + 'static,
+                F: Any + 'static,
+                G: Any + 'static,
+                H: Any + 'static,
+            {
+                type Output<'a> = (&'a mut A, &'a mut B, &'a mut C, &'a mut D, &'a mut E, &'a mut F, &'a mut G, &'a mut H);
+                fn get_from_mut<'a>(map: &'a mut HashMap<TypeId, Box<dyn Any>>) -> Option<Self::Output<'a>> {
+                    let ids = [TypeId::of::<A>(), TypeId::of::<B>(), TypeId::of::<C>(), TypeId::of::<D>(), TypeId::of::<E>(), TypeId::of::<F>(), TypeId::of::<G>(), TypeId::of::<H>()];
+                    for i in 0..ids.len() { for j in (i+1)..ids.len() { if ids[i] == ids[j] { return None; } } }
+                    let ptr_a = { map.get_mut(&TypeId::of::<A>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    let ptr_b = { map.get_mut(&TypeId::of::<B>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    let ptr_c = { map.get_mut(&TypeId::of::<C>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    let ptr_d = { map.get_mut(&TypeId::of::<D>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    let ptr_e = { map.get_mut(&TypeId::of::<E>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    let ptr_f = { map.get_mut(&TypeId::of::<F>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    let ptr_g = { map.get_mut(&TypeId::of::<G>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    let ptr_h = { map.get_mut(&TypeId::of::<H>()).map(|v| v.as_mut() as *mut dyn Any) }?;
+                    unsafe {
+                        let a = (&mut *ptr_a).downcast_mut::<A>()?;
+                        let b = (&mut *ptr_b).downcast_mut::<B>()?;
+                        let c = (&mut *ptr_c).downcast_mut::<C>()?;
+                        let d = (&mut *ptr_d).downcast_mut::<D>()?;
+                        let e = (&mut *ptr_e).downcast_mut::<E>()?;
+                        let f = (&mut *ptr_f).downcast_mut::<F>()?;
+                        let g = (&mut *ptr_g).downcast_mut::<G>()?;
+                        let h = (&mut *ptr_h).downcast_mut::<H>()?;
+                        Some((a, b, c, d, e, f, g, h))
+                    }
+                }
+            }
+        }
+    };
+}
+
+// pub struct TypeMap {
+//     map: HashMap<TypeId, Box<dyn Any>>,
+// }
+//
+// impl TypeMap {
+//     pub fn new() -> Self {
+//         Self {
+//             map: HashMap::new(),
+//         }
+//     }
+//
+//     pub fn insert<T: Any + 'static>(&mut self, value: T) -> Option<Box<T>> {
+//         let type_id = TypeId::of::<T>();
+//         self.map
+//             .insert(type_id, Box::new(value))
+//             .and_then(|boxed| boxed.downcast().ok())
+//     }
+//
+//     pub fn get<T>(&self) -> Option<&T>
+//     where
+//         T: Any + 'static,
+//     {
+//         self.map.get(&TypeId::of::<T>())
+//             .and_then(|any| any.downcast_ref::<T>())
+//     }
+//
+//     pub fn get_mut<T>(&mut self) -> Option<&mut T>
+//     where
+//         T: Any + 'static,
+//     {
+//         self.map.get_mut(&TypeId::of::<T>()).and_then(|any| any.downcast_mut::<T>())
+//     }
+//
+//     pub fn remove<T: Any>(&mut self) -> Option<Box<T>> {
+//         unimplemented!()
+//     }
+// }
+//
+// impl Default for TypeMap {
+//     fn default() -> Self {
+//         Self::new()
+//     }
+// }
+
+#[cfg(test)]
+mod tests {
+    use crate::define_typemap;
+
+    define_typemap!(TestMap,);
+
+    #[test]
+    fn get_test() {
+        let mut tm = TestMap::new();
+        tm.insert::<u32>(42);
+        let v = tm.get::<u32>().expect("value should be present");
+        assert_eq!(*v, 42);
+    }
+
+    #[test]
+    fn get_many_test() {
+        let mut tm = TestMap::new();
+        tm.insert::<u32>(1);
+        tm.insert::<i32>(-2);
+        tm.insert::<f32>(3.5);
+
+        let (a, b, c) = tm
+            .get_many::<(u32, i32, f32)>()
+            .expect("all values should be present");
+        assert_eq!((*a, *b, *c), (1, -2, 3.5));
+    }
+
+    #[test]
+    fn get_many_mut_test() {
+        let mut tm = TestMap::new();
+
+        tm.insert::<i32>(-2);
+        tm.insert::<u32>(1);
+        tm.insert::<f32>(3.5);
+
+        let (a, b, c) = tm
+            .get_many_mut::<(i32, u32, f32)>()
+            .expect("all values should be present");
+        *a = 4;
+        *b = 5;
+        *c = 6.5;
+    }
+}

ecs/Cargo.toml

@@ -6,3 +6,4 @@ edition = "2024"
 [dependencies]
 glam = "0.30.5"
 raidillon_assets = { path = "../asset" }
+rapier3d = "0.30.1"

ecs/src/components.rs

@@ -15,3 +15,16 @@ impl Transform {
 }
 
 pub struct ModelHandle(pub ModelID);
+
+#[derive(Copy, Clone)]
+pub struct RigidBodyComponent(pub rapier3d::dynamics::RigidBodyHandle);
+
+#[derive(Copy, Clone)]
+pub struct CharacterBodyComponent(pub rapier3d::dynamics::RigidBodyHandle);
+
+#[derive(Debug, Default, PartialEq, Eq, Clone, Copy)]
+pub enum CameraMode {
+    #[default]
+    Kinematic,
+    Debug,
+}

engine/Cargo.toml

@@ -7,6 +7,9 @@ edition = "2024"
 raidillon_assets = { path = "../asset" }
 raidillon_core = { path = "../core" }
 raidillon_platform = { path = "../platform" }
+raidillon_ecs = { path = "../ecs" }
 winit = "0.30.12"
 hecs = "0.10.5"
 indexmap = "2.10.0"
+glam = "0.30.8"
+egui = "0.33.2"

engine/src/engine.rs

@@ -2,25 +2,37 @@ use std::cell::RefCell;
 use std::rc::Rc;
 use raidillon_core::scene::{Scene, SceneManager};
 use crate::system::{SystemContext, SystemManager};
-use raidillon_core::context::PlatformContext;
-use raidillon_core::DebugUIBuffer;
+use raidillon_platform::PlatformContext;
+use raidillon_core::{define_typemap};
 use raidillon_core::engine::EngineTrait;
+use crate::input::InputState;
+use crate::resources::EngineResources;
 
 pub struct Engine {
     pub scene_manager: SceneManager,
     pub system_manager: SystemManager,
-    debug_ui_buffer: Rc<RefCell<DebugUIBuffer>>,
+    pub resources: EngineResources,
+}
+
+impl Engine {
+    fn load_default_resources(&mut self) {
+        let input = InputState::default();
+        self.resources.insert(input);
+    }
 }
 
 impl EngineTrait for Engine {
+    type PlatformCtx = PlatformContext;
     fn new() -> Self {
         let scene_manager = SceneManager::new();
         let system_manager = SystemManager::new();
-        Self {
+        let mut s = Self {
             scene_manager,
             system_manager,
-            debug_ui_buffer: Rc::new(RefCell::new(DebugUIBuffer::new())),
-        }
+            resources: EngineResources::new(),
+        };
+        s.load_default_resources();
+        s
     }
 
     /// Initialize systems, load the world.
@@ -29,42 +41,34 @@ impl EngineTrait for Engine {
         for system in self.system_manager.systems.values_mut() {
             system.initialize();
         }
-
-        let mut ctx = SystemContext {
-            scene: self.scene_manager.current_mut(),
-            platform_context,
-            debug_ui_buffer: self.debug_ui_buffer.clone(),
-        };
-
+        self.resources.insert(platform_context);
         // Engine Loading Stage 2: load world
         for system in self.system_manager.systems.values_mut() {
-            system.load_world(&mut ctx);
+            system.load_world(&mut self.resources, &mut self.scene_manager.current_mut());
         }
     }
 
     /// Update the engine
-    fn update(&mut self, platform_context: PlatformContext) {
-        self.debug_ui_buffer.borrow_mut().reset_buffer();
-        let mut ctx = SystemContext {
-            scene: self.scene_manager.current_mut(),
-            platform_context,
-            debug_ui_buffer: self.debug_ui_buffer.clone(),
-        };
+    fn frame_update(&mut self, platform_context: PlatformContext) {
+        self.resources.insert(platform_context);
 
         for system in self.system_manager.systems.values_mut() {
-            system.update(&mut ctx);
+            system.frame_update(&mut self.resources, &mut self.scene_manager.current_mut());
+        }
+    }
+
+    fn fixed_update(&mut self, platform_context: PlatformContext) {
+        self.resources.insert(platform_context);
+        for system in self.system_manager.systems.values_mut() {
+            system.fixed_update(&mut self.resources, &mut self.scene_manager.current_mut());
         }
     }
 
     fn handle_event(&mut self, platform_context: PlatformContext) {
-        let mut ctx = SystemContext {
-            scene: self.scene_manager.current_mut(),
-            platform_context,
-            debug_ui_buffer: self.debug_ui_buffer.clone(),
-        };
-
+        self.resources.get_mut::<InputState>().unwrap().handle_event(&platform_context.current_event);
+        self.resources.insert(platform_context);
         for system in self.system_manager.systems.values_mut() {
-            system.handle_event(&mut ctx);
+            system.handle_event(&mut self.resources, &mut self.scene_manager.current_mut());
         }
     }
 
@@ -78,16 +82,7 @@ impl EngineTrait for Engine {
         self.scene_manager.current_mut()
     }
 
-    fn get_debug_ui_buffer(&self) -> Rc<RefCell<DebugUIBuffer>> {   
-        self.debug_ui_buffer.clone()
-    }
-
-    fn reset_debug_ui_buffer(&mut self) {
-        self.debug_ui_buffer.borrow_mut().reset_buffer();
-    }
-
-    fn scene_and_debug_ui_buffer_mut(&mut self) -> (&mut Scene, Rc<RefCell<DebugUIBuffer>>) {
-        let (sm, dub) = (&mut self.scene_manager, &mut self.debug_ui_buffer);
-        (sm.current_mut(), dub.clone())
+    fn current_scene(&self) -> &Scene {
+        self.scene_manager.current()
     }
 }

engine/src/input.rs

@@ -0,0 +1,69 @@
+use std::collections::HashSet;
+use winit::event::{ElementState, Event, MouseButton, WindowEvent};
+use winit::keyboard::{KeyCode, PhysicalKey};
+
+/// A utility to help with buffering input.
+/// Meant to be plugged into systems.
+#[derive(Default, Clone, Debug)]
+pub struct InputState {
+    held_keys: HashSet<KeyCode>,
+    held_mouse: HashSet<MouseButton>,
+}
+
+impl InputState {
+    fn new() -> Self {
+        Default::default()
+    }
+
+    pub fn handle_event(&mut self, event: &Event<()>) {
+        if let Event::WindowEvent { event, .. } = event {
+            match event {
+                // Keyboard
+                WindowEvent::KeyboardInput { event: key_event, .. } => {
+                    if let PhysicalKey::Code(code) = key_event.physical_key {
+                        match key_event.state {
+                            ElementState::Pressed => {
+                                self.held_keys.insert(code);
+                            }
+                            ElementState::Released => {
+                                self.held_keys.remove(&code);
+                            }
+                        }
+                    }
+                }
+
+                // Mouse
+                WindowEvent::MouseInput { state, button, .. } => {
+                    match state {
+                        ElementState::Pressed => {
+                            self.held_mouse.insert(*button);
+                        }
+                        ElementState::Released => {
+                            self.held_mouse.remove(button);
+                        }
+                    }
+                }
+
+                WindowEvent::Focused(focused) => {
+                    if !*focused {
+                        self.clear();
+                    }
+                }
+                _ => {}
+            }
+        }
+    }
+
+    pub fn key_held(&self, code: KeyCode) -> bool {
+        self.held_keys.contains(&code)
+    }
+
+    pub fn mouse_held(&self, button: MouseButton) -> bool {
+        self.held_mouse.contains(&button)
+    }
+
+    pub fn clear(&mut self) {
+        self.held_keys.clear();
+        self.held_mouse.clear();
+    }
+}

engine/src/lib.rs

@@ -1,4 +1,9 @@
 pub mod engine;
 pub mod system;
+mod input;
+pub mod systems;
+mod resources;
 
 pub use crate::engine::Engine;
+pub use crate::resources::EngineResources;
+pub use input::InputState;

engine/src/resources.rs

@@ -0,0 +1,3 @@
+use raidillon_core::define_typemap;
+
+define_typemap!(EngineResources,);

engine/src/system.rs

@@ -1,25 +1,26 @@
+use indexmap::IndexMap;
+use raidillon_core::scene::Scene;
+use raidillon_platform::PlatformContext;
 use std::any::TypeId;
 use std::cell::RefCell;
 use std::rc::Rc;
-use indexmap::IndexMap;
-use raidillon_core::context::PlatformContext;
-use raidillon_core::scene::Scene;
-use raidillon_core::DebugUIBuffer;
+use crate::input::InputState;
+use crate::resources::EngineResources;
 
 pub struct SystemContext<'a> {
-    // TODO: time delta etc.
     pub scene: &'a mut Scene,
     pub platform_context: PlatformContext,
-    pub debug_ui_buffer: Rc<RefCell<DebugUIBuffer>>,
+    pub input_state: Rc<RefCell<InputState>>,
 }
 
 pub trait System {
     /// Initialize the system.
     fn initialize(&mut self) {}
     /// Spawn the first entities of the world.
-    fn load_world(&mut self, _ctx: &mut SystemContext) {}
-    fn handle_event(&mut self, _ctx: &mut SystemContext) {}
-    fn update(&mut self, _ctx: &mut SystemContext) {}
+    fn load_world(&mut self, res: &mut EngineResources, scene: &mut Scene) {}
+    fn handle_event(&mut self, res: &mut EngineResources, scene: &mut Scene) {}
+    fn fixed_update(&mut self, res: &mut EngineResources, scene: &mut Scene) {}
+    fn frame_update(&mut self, res: &mut EngineResources, scene: &mut Scene) {}
 }
 
 pub struct SystemManager {

game/Cargo.toml

@@ -3,16 +3,10 @@ name = "raidillon_game"
 version = "0.1.0"
 edition = "2024"
 
-[features]
-default = ["glium"]
-glium = ["raidillon_glium"]
-
 [dependencies]
-raidillon_core = { path = "../core" }
-raidillon_platform = { path = "../platform" }
-raidillon_assets = { path = "../asset" }
-raidillon_ecs = { path = "../ecs" }
-raidillon_engine = { path = "../engine" }
-raidillon_glium = { path = "../glium_platform", optional = true }
+raidillon_app = { path = "../app", features = ["glium"] }
 glam = "0.30.5"
 winit = "0.30.12"
+rapier3d = "0.30.1"
+hecs = "0.10.5"
+egui = "0.33.2"

game/src/main.rs

@@ -1,28 +1,31 @@
+use raidillon_app::prelude::*;
+
+mod systems;
 use glam::{Quat, Vec3};
-use raidillon_engine::{Engine, system::System};
-use raidillon_engine::system::SystemContext;
-use raidillon_platform::{Platform, Camera};
-use raidillon_assets::model_path;
-use raidillon_core::engine::EngineTrait;
-use raidillon_ecs::components::ModelHandle;
-use raidillon_ecs::Transform;
-use raidillon_core::scene::Scene;
-#[cfg(feature = "glium")]
-use raidillon_glium::GliumPlatform;
+use rapier3d::dynamics::{CoefficientCombineRule, RigidBodyType};
+use rapier3d::prelude::ColliderBuilder;
 use winit::event::{Event, WindowEvent};
+use systems::debug_camera::FPSDebugCameraSystem;
+use crate::systems::common::should_draw_menu;
+use crate::systems::{
+    DisplaySettings, KeybindsSystem, KinematicCharacterController, MenuSystem, PhysicsSystem,
+    PhysicsDebugSystem,
+};
 
-const TEST_GLTF: &str = "pink-monkey.gltf";
-
+const TEST_GLTF: &str = "checkered-sphere.glb";
+const PLANE_GLTF: &str = "plane.glb";
 const MAIN_SCENE_ID: &str = "main_scene";
 
 #[derive(Default)]
 struct UpdateAspectRatioSystem;
 impl System for UpdateAspectRatioSystem {
-    fn handle_event(&mut self, ctx: &mut SystemContext) {
+    fn handle_event(&mut self, res: &mut EngineResources, scene: &mut Scene) {
+        let pctx = res.get::<PlatformContext>().unwrap();
+
         if let Event::WindowEvent { event: WindowEvent::Resized(sz), .. } =
-            &ctx.platform_context.current_event
+            pctx.current_event
         {
-            ctx.scene.world
+            scene.world
                 .query_mut::<&mut Camera>()
                 .into_iter()
                 .for_each(|(_, cam)| {
@@ -33,64 +36,105 @@ impl System for UpdateAspectRatioSystem {
 }
 
 #[derive(Default)]
-struct RenderingTestSystem;
-impl System for RenderingTestSystem {
-    fn initialize(&mut self) {}
-    fn load_world(&mut self, ctx: &mut SystemContext) {
-        ctx.scene.world.spawn((Camera {
-            eye:    Vec3::new(0.0, 0.0, 2.0),
+struct MainSystem;
+
+impl System for MainSystem {
+    fn load_world(&mut self, res: &mut EngineResources, scene: &mut Scene) {
+        let pctx = res.get::<PlatformContext>().expect("PlatformContext missing").clone();
+        let physics = scene.resources.get_mut::<Physics>().expect("Physics missing");
+
+        // Spawn Sphere
+        {
+            let tr = Transform {
+                translation: Vec3::new(0.0, 5.0, 0.0),
+                rotation: Quat::IDENTITY,
+                scale: Vec3::new(1.0, 1.0, 1.0),
+            };
+            let collider = ColliderBuilder::ball(1.0)
+                .restitution(0.7)
+                .restitution_combine_rule(CoefficientCombineRule::Max)
+                .build();
+            let rb_handle = physics.add_rigid_body(RigidBodyType::Dynamic, tr, collider);
+            pctx.asset_manager.borrow_mut().load_gltf(TEST_GLTF, &model_path(TEST_GLTF));
+            scene.world.spawn((
+                tr,
+                ModelHandle(TEST_GLTF),
+                RigidBodyComponent(rb_handle),
+            ));
+        }
+        // Spawn Plane
+        {
+            let tr = Transform {
+                translation: Vec3::new(0.0, 0.0, 0.0),
+                rotation: Quat::IDENTITY,
+                scale: Vec3::new(10.0, 1.0, 10.0),
+            };
+            let collider = ColliderBuilder::cuboid(10.0, 0.01, 10.0).build();
+            let rb_handle = physics.add_rigid_body(RigidBodyType::Fixed, tr, collider);
+            pctx.asset_manager.borrow_mut().load_gltf(PLANE_GLTF, &model_path(PLANE_GLTF));
+            scene.world.spawn((
+                tr,
+                ModelHandle(PLANE_GLTF),
+                RigidBodyComponent(rb_handle),
+            ));
+        }
+
+        scene.world.spawn((Camera {
+            eye:    Vec3::new(0.0, 2.0, 3.0),
             center: Vec3::ZERO,
             up:     Vec3::Y,
             fovy:   60_f32.to_radians(),
-            aspect: ctx.platform_context.frame_width / ctx.platform_context.frame_height,
+            aspect: pctx.frame_width / pctx.frame_height,
             znear:  0.1,
-            zfar:   100.0,
-        },));
-
-        let mut am = ctx.platform_context.asset_manager.borrow_mut();
-
-        am.load_gltf(TEST_GLTF, &model_path(TEST_GLTF));
-
-        ctx.scene.world.spawn((
-            Transform {
-              translation: Vec3::new(0.0, 0.0, 0.0),
-              rotation:    Quat::IDENTITY,
-              scale:       Vec3::new(1.0, 1.0, 1.0),
-            },
-            ModelHandle(TEST_GLTF),
+            zfar:   100.0},
+            CameraMode::default(),
         ));
     }
 
-    fn update(&mut self, ctx: &mut SystemContext) {
-        ctx.debug_ui_buffer.borrow_mut().text("Hello World!".to_owned());
+    fn frame_update(&mut self, res: &mut EngineResources, scene: &mut Scene) {
+        let (
+            pctx,
+            input,
+        ) = res.get_many_mut::<(
+            PlatformContext,
+            InputState,
+        )>().unwrap();
+
+        let mut egui_queue = pctx.egui_queue.borrow_mut();
+        let time_ctx = pctx.time_ctx.clone();
+        let mut character_pos = Vec3::ZERO;
+        for (_ent, (tr, ch_component)) in scene.world.query::<(&Transform, &CharacterBodyComponent)>().iter() {
+            character_pos = tr.translation;
+        }
+        egui_queue.queue(move |egui_ctx| {
+            // disable text selection on all labels.
+            egui_ctx.style_mut(|style| {
+                style.interaction.selectable_labels = false;
+            });
+
+            egui::Window::new("Debug").show(egui_ctx, |ui| {
+                ui.label("Hello World!");
+                ui.label(format!("Frame Delta: {:.3}", time_ctx.frame_dt));
+                ui.label(format!("Fixed Delta: {:.3}", time_ctx.fixed_dt));
+                ui.label(format!("FPS: {:.3}", 1.0 / time_ctx.frame_dt));
+                ui.label(format!("Character POS: {character_pos:.3}"));
+            });
+        });
     }
 }
 
 fn main() {
-    let mut engine = Engine::new();
-    // Define systems
-    engine.system_manager.add::<RenderingTestSystem>();
-    engine.system_manager.add::<UpdateAspectRatioSystem>();
-
-    // Set up the scene
-    let main_scene = Scene::new(
-        MAIN_SCENE_ID.to_owned(),
-        None,
-    );
-    engine.scene_manager.add_scene(MAIN_SCENE_ID, main_scene);
-    engine.scene_manager.set_active_scene(MAIN_SCENE_ID);
-
-    #[cfg(feature = "glium")]
-    {
-        let platform = GliumPlatform::initialize(
-            engine,
-            "Raidillon".to_string(),
-            1920,
-            1080,
-        );
-        platform.run()
-    };
-
-    #[cfg(not(any(feature = "glium")))]
-    compile_error!("No platform feature enabled.");
+    raidillon_app::App::new()
+        .add_system::<PhysicsSystem>()
+        .add_system::<PhysicsDebugSystem>()
+        .add_system::<KeybindsSystem>()
+        .add_system::<KinematicCharacterController>()
+        .add_system::<FPSDebugCameraSystem>()
+        .add_system::<MenuSystem>()
+        .add_system::<DisplaySettings>()
+        .add_system::<MainSystem>()
+        .add_system::<UpdateAspectRatioSystem>()
+        .add_scene(MAIN_SCENE_ID, Scene::new(MAIN_SCENE_ID.to_owned(), None))
+        .set_active_scene(MAIN_SCENE_ID)
+        .run("Raidillon".to_string(), 2560, 1080);
 }

game/src/systems/common.rs

@@ -0,0 +1,34 @@
+use glam::Vec3;
+use raidillon_app::prelude::*;
+use crate::systems::menu::MenuState;
+
+pub fn is_camera_mode_valid(scene: &mut Scene, mode: CameraMode) -> bool {
+    let mut q = scene.world.query::<(&Camera, &CameraMode)>();
+    let (cam_ent, (cam, cam_mode)) = q
+        .iter()
+        .next()
+        .unwrap();
+    *cam_mode == mode
+}
+
+pub fn is_mouse_look_enabled(scene: &mut Scene) -> bool {
+    let mut q = scene.world.query::<(&MenuState)>();
+    let (_ent, mode) = q.iter().next().unwrap();
+    *mode == MenuState::Closed
+}
+
+pub fn camera_front(yaw: f32, pitch: f32) -> Vec3 {
+    let yaw_rad   = yaw.to_radians();
+    let pitch_rad = pitch.to_radians();
+    Vec3::new(
+        yaw_rad.cos() * pitch_rad.cos(),
+        pitch_rad.sin(),
+        yaw_rad.sin() * pitch_rad.cos(),
+    ).normalize()
+}
+
+pub fn should_draw_menu(scene: &mut Scene) -> bool {
+    let mut q = scene.world.query::<(&MenuState)>();
+    let (_ent, mode) = q.iter().next().unwrap();
+    *mode == MenuState::Open
+}

game/src/systems/debug_camera.rs

@@ -0,0 +1,89 @@
+use glam::{Quat, Vec3};
+use winit::event::DeviceEvent::MouseMotion;
+use winit::event::{ElementState, Event, MouseButton, WindowEvent};
+use winit::keyboard::{KeyCode, PhysicalKey};
+use winit::window::CursorGrabMode;
+use raidillon_app::prelude::*;
+
+use crate::systems::common::{camera_front, is_camera_mode_valid, is_mouse_look_enabled};
+use crate::systems::menu::MenuState;
+
+pub struct FPSDebugCameraSystem {
+    mouse_delta: (f64, f64),
+    position: Vec3,
+    yaw:   f32,
+    pitch: f32,
+    speed: f32,
+    sensitivity: f32,
+}
+
+impl Default for FPSDebugCameraSystem {
+    fn default() -> Self {
+        Self {
+            mouse_delta: Default::default(),
+            position: Vec3::new(0.0, 0.0, 2.0),
+            yaw: -90.0,
+            pitch: 0.0,
+            speed: 8.0,
+            sensitivity: 0.1,
+        }
+    }
+}
+
+impl System for FPSDebugCameraSystem {
+    fn handle_event(&mut self, res: &mut EngineResources, scene: &mut Scene) {
+        if !(is_camera_mode_valid(scene, CameraMode::Debug) && is_mouse_look_enabled(scene)) {
+            return
+        }
+        let pctx = res.get::<PlatformContext>().unwrap();
+        let event2 = pctx.current_event.clone();
+        match event2 {
+            Event::DeviceEvent { device_id, event} => {
+                match event {
+                    MouseMotion { delta } => {
+                        self.mouse_delta.0 += delta.0;
+                        self.mouse_delta.1 += delta.1;
+                    },
+                    _ => {}
+                }
+            },
+            _ => {},
+        }
+    }
+
+    fn frame_update(&mut self, res: &mut EngineResources, scene: &mut Scene) {
+        let (pctx, input) = res.get_many::<(PlatformContext, InputState)>().unwrap();
+
+        if is_mouse_look_enabled(scene) {
+            self.yaw += self.mouse_delta.0 as f32 * self.sensitivity;
+            self.pitch -= self.mouse_delta.1 as f32 * self.sensitivity;
+            self.pitch = self.pitch.clamp(-89.0, 89.0);
+        }
+
+        let front = camera_front(self.yaw, self.pitch);
+        let right_vec = front.cross(Vec3::Y).normalize();
+
+        if is_mouse_look_enabled(scene) {
+            if input.key_held(KeyCode::KeyW) {
+                self.position += front * pctx.time_ctx.frame_dt * self.speed;
+            }
+            if input.key_held(KeyCode::KeyS) {
+                self.position -= front * pctx.time_ctx.frame_dt * self.speed;
+            }
+            if input.key_held(KeyCode::KeyA) {
+                self.position -= right_vec * pctx.time_ctx.frame_dt * self.speed;
+            }
+            if input.key_held(KeyCode::KeyD) {
+                self.position += right_vec * pctx.time_ctx.frame_dt * self.speed;
+            }
+        }
+
+        if is_camera_mode_valid(scene, CameraMode::Debug) {
+            scene.world.query_mut::<&mut Camera>().into_iter().for_each(|(_, camera)| {
+                camera.eye = self.position;
+                camera.center = self.position + front;
+            });
+        }
+        self.mouse_delta = (0.0, 0.0);
+    }
+}

game/src/systems/display_settings.rs

@@ -0,0 +1,94 @@
+use std::sync::{Arc, Mutex};
+use raidillon_app::prelude::*;
+use crate::systems::common::should_draw_menu;
+
+#[derive(Clone, Copy, PartialEq, Eq)]
+enum SettingsTab {
+    Display,
+}
+
+impl Default for SettingsTab {
+    fn default() -> Self {
+        SettingsTab::Display
+    }
+}
+
+#[derive(Clone, Default)]
+struct DisplaySettingsUiState {
+    selected_fullscreen_mode: WindowMode,
+    active_tab: SettingsTab,
+}
+
+#[derive(Default)]
+pub struct DisplaySettings {
+    ui_state: Arc<Mutex<DisplaySettingsUiState>>,
+}
+
+impl System for DisplaySettings {
+    fn load_world(&mut self, res: &mut EngineResources, scene: &mut Scene) {
+        let pctx = res.get_mut::<PlatformContext>().unwrap();
+
+        // sync the settings with UI state once
+        if let (Ok(settings_handle), Ok(mut state)) = (pctx.settings.read(), self.ui_state.lock()) {
+            state.selected_fullscreen_mode = settings_handle.display_settings.fullscreen_mode;
+        }
+    }
+
+    fn frame_update(&mut self, res: &mut EngineResources, scene: &mut Scene) {
+        if should_draw_menu(scene) {
+            let pctx = res.get_mut::<PlatformContext>().unwrap();
+            let settings = pctx.settings.clone();
+            let ui_state = self.ui_state.clone();
+
+            pctx.egui_queue.borrow_mut().queue(move |egui_ctx| {
+                egui::Window::new("Settings").default_open(false).show(egui_ctx, |ui| {
+                    let mut state = ui_state.lock().unwrap();
+
+                    ui.horizontal(|ui| {
+                        ui.selectable_value(&mut state.active_tab, SettingsTab::Display, "Display Settings");
+                    });
+                    ui.separator();
+
+                    match state.active_tab {
+                        SettingsTab::Display => {
+                            ui.label("Window Mode");
+                            egui::ComboBox::from_id_salt("window_mode")
+                                .selected_text(window_mode_label(state.selected_fullscreen_mode))
+                                .show_ui(ui, |ui| {
+                                    for mode in [
+                                        WindowMode::Windowed,
+                                        WindowMode::BorderlessFullscreen,
+                                        WindowMode::ExclusiveFullscreen,
+                                    ] {
+                                        ui.selectable_value(
+                                            &mut state.selected_fullscreen_mode,
+                                            mode,
+                                            window_mode_label(mode),
+                                        );
+                                    }
+                                });
+
+                            ui.add_space(8.0);
+                            ui.with_layout(egui::Layout::right_to_left(egui::Align::Center), |ui| {
+                                if ui.button("Apply").clicked() {
+                                    if let Ok(mut settings_handle) = settings.write() {
+                                        settings_handle.display_settings.fullscreen_mode = state.selected_fullscreen_mode;
+                                        settings_handle.display_settings.dirty = true;
+                                    }
+                                }
+                            });
+                        }
+                    }
+                });
+            });
+        }
+    }
+}
+
+fn window_mode_label(mode: WindowMode) -> &'static str {
+    match mode {
+        WindowMode::Windowed => "Windowed",
+        WindowMode::BorderlessFullscreen => "Borderless Fullscreen",
+        WindowMode::ExclusiveFullscreen => "Exclusive Fullscreen",
+    }
+}

game/src/systems/keybinds.rs

@@ -0,0 +1,69 @@
+use winit::keyboard::KeyCode;
+use raidillon_app::prelude::*;
+
+use crate::systems::{common::should_draw_menu, menu::MenuState};
+
+#[derive(Default)]
+pub struct KeybindsSystem {
+    camera_toggle_held: bool,
+}
+
+impl System for KeybindsSystem {
+    fn fixed_update(&mut self, res: &mut EngineResources, scene: &mut Scene) {
+        let input = res.get::<InputState>().unwrap();
+        if input.key_held(KeyCode::F5) {
+            if self.camera_toggle_held { return }
+            self.toggle_camera_mode(scene);
+            self.camera_toggle_held = true;
+        } else {
+            self.camera_toggle_held = false;
+        }
+    }
+
+    fn frame_update(&mut self, res: &mut EngineResources, scene: &mut Scene) {
+        if should_draw_menu(scene) {
+            let pctx = res.get_mut::<PlatformContext>().unwrap();
+            let mut q = scene.world.query::<(&Camera, &CameraMode)>();
+            let (cam_ent, (cam, cam_mode)) = q
+                .iter()
+                .next()
+                .unwrap();
+            let cam_mode_str = format!("Camera Mode: {:?}", cam_mode);
+
+            let mut q = scene.world.query::<(&MenuState)>();
+            let (_ent, menu_state) = q
+                .iter()
+                .next()
+                .unwrap();
+
+            let menu_state_str = format!("Menu State: {:?}", menu_state);
+
+            pctx.egui_queue.borrow_mut().queue(move |egui_ctx| {
+                egui::Window::new("Camera").show(egui_ctx, |ui| {
+                    ui.label("F5 to switch camera");
+                    ui.label(cam_mode_str);
+                    ui.label(menu_state_str)
+                });
+            });
+        }
+    }
+}
+
+impl KeybindsSystem {
+    fn toggle_camera_mode(&mut self, scene: &mut Scene) {
+        let q = scene.world.query_mut::<(&mut Camera, &mut CameraMode)>();
+        let (cam_ent, (cam, cam_mode)) = q
+            .into_iter()
+            .next()
+            .unwrap();
+
+        match *cam_mode {
+            CameraMode::Kinematic => {
+                *cam_mode = CameraMode::Debug;
+            }
+            CameraMode::Debug => {
+                *cam_mode = CameraMode::Kinematic;
+            }
+        }
+    }
+}

game/src/systems/kinematic_character_controller.rs

@@ -0,0 +1,187 @@
+use glam::{Quat, Vec3};
+use rapier3d::prelude::{nalgebra, ColliderBuilder, QueryFilter, RigidBodyBuilder, RigidBodyType};
+use rapier3d::prelude::vector;
+use rapier3d::control::{CharacterCollision, KinematicCharacterController as RapierKinematicCharacterController};
+use rapier3d::na::{Isometry3, Vector3};
+use winit::event::DeviceEvent::MouseMotion;
+use winit::event::Event;
+use winit::keyboard::KeyCode;
+use raidillon_app::prelude::*;
+
+use crate::systems::common::{camera_front, is_camera_mode_valid, is_mouse_look_enabled};
+use crate::systems::menu::MenuState;
+
+#[derive(Default)]
+pub struct KinematicCharacterController {
+    character_controller: RapierKinematicCharacterController,
+    character_collider: ColliderBuilder,
+
+    desired_movement: Vec3,
+    last_position: Vector3<f32>,
+    yaw:   f32,
+    pitch: f32,
+    speed: f32,
+    sensitivity: f32,
+    mouse_delta: (f64, f64),
+
+    vertical_velocity: f32,
+    gravity: f32,
+    max_fall_speed: f32,
+}
+
+impl System for KinematicCharacterController {
+    fn load_world(&mut self, res: &mut EngineResources, scene: &mut Scene) {
+        // create the rigid body, add it to the body set
+        let p = scene.resources.get_mut::<Physics>().expect("Physics missing");
+        let rb = RigidBodyBuilder::kinematic_position_based().build();
+        let rb_handle = p.rigid_body_set.insert(rb);
+        self.character_collider = ColliderBuilder::capsule_y(1.0, 1.0);
+        p.collider_set.insert_with_parent(self.character_collider.build(), rb_handle, &mut p.rigid_body_set);
+        let tr = Transform {
+            translation: Vec3::new(0.0, 2.0, 3.0),
+            rotation: Quat::IDENTITY,
+            scale: Vec3::new(1.0, 1.0, 1.0),
+        };
+        self.last_position = vector![
+            tr.translation.x,
+            tr.translation.y,
+            tr.translation.z,
+        ];
+        scene.world.spawn((
+            tr,
+            CharacterBodyComponent(rb_handle),
+        ));
+
+        self.speed = 5.0;
+        self.sensitivity = 0.05;
+        self.gravity = -9.81;
+        self.max_fall_speed = -50.0;
+        self.vertical_velocity = 0.0;
+    }
+
+    fn handle_event(&mut self, res: &mut EngineResources, scene: &mut Scene) {
+        if !is_camera_mode_valid(scene, CameraMode::Kinematic) {
+            return
+        }
+
+        let pctx = res.get::<PlatformContext>().unwrap();
+        let event2 = pctx.current_event.clone();
+        match event2 {
+            Event::DeviceEvent { device_id, event } => {
+                match event {
+                    MouseMotion { delta } => {
+                        self.mouse_delta.0 += delta.0;
+                        self.mouse_delta.1 += delta.1;
+                    },
+                    _ => {}
+                }
+            },
+            _ => {},
+        }
+    }
+
+    fn frame_update(&mut self, res: &mut EngineResources, scene: &mut Scene) {
+        let front = camera_front(self.yaw, self.pitch);
+        let right_vec = front.cross(Vec3::Y).normalize();
+
+        if is_camera_mode_valid(scene, CameraMode::Kinematic) && is_mouse_look_enabled(scene) {
+            let (pctx, input) = res.get_many::<(PlatformContext, InputState)>().unwrap();
+
+            self.yaw   += (self.mouse_delta.0 as f32) * self.sensitivity;
+            self.pitch -= (self.mouse_delta.1 as f32) * self.sensitivity;
+            self.pitch = self.pitch.clamp(-89.0, 89.0);
+
+            if input.key_held(KeyCode::KeyW) {
+                self.desired_movement += front * pctx.time_ctx.frame_dt * self.speed;
+            }
+            if input.key_held(KeyCode::KeyS) {
+                self.desired_movement -= front * pctx.time_ctx.frame_dt * self.speed;
+            }
+            if input.key_held(KeyCode::KeyA) {
+                self.desired_movement -= right_vec * pctx.time_ctx.frame_dt * self.speed;
+            }
+            if input.key_held(KeyCode::KeyD) {
+                self.desired_movement += right_vec * pctx.time_ctx.frame_dt * self.speed;
+            }
+        }
+
+        if is_camera_mode_valid(scene, CameraMode::Kinematic) {
+            let pos = Physics::rapier_translation_to_glam(&self.last_position);
+
+            scene.world.query_mut::<&mut Camera>().into_iter().for_each(|(_, camera)| {
+                // INTERPOLATION NEEDED.
+                camera.eye = pos;
+                camera.center = pos + front;
+            });
+        }
+
+        self.mouse_delta = (0.0, 0.0);
+    }
+
+    fn fixed_update(&mut self, res: &mut EngineResources, scene: &mut Scene) {
+        let p = scene.resources.get_mut::<Physics>().unwrap();
+        let (pctx, input) = res.get_many::<(PlatformContext, InputState)>().unwrap();
+
+        let (ch_ent, (ch_tr, ch_component)) = scene
+            .world
+            .query_mut::<(&mut Transform, &mut CharacterBodyComponent)>()
+            .into_iter()
+            .next()
+            .expect("no character entity in world");
+
+        let query_pipeline = p.broad_phase.as_query_pipeline(
+            p.narrow_phase.query_dispatcher(),
+            &p.rigid_body_set,
+            &p.collider_set,
+            QueryFilter::default().exclude_rigid_body(ch_component.0),
+        );
+
+        self.vertical_velocity = (self.vertical_velocity + self.gravity * pctx.time_ctx.fixed_dt)
+            .max(self.max_fall_speed);
+        let mut total_displacement = self.desired_movement;
+        total_displacement.y += self.vertical_velocity * pctx.time_ctx.fixed_dt;
+
+        let mut collisions: Vec<CharacterCollision> = Vec::new();
+        let corrected_movement = self.character_controller.move_shape(
+            pctx.time_ctx.fixed_dt,
+            &query_pipeline,
+            &*self.character_collider.shape,
+            &Isometry3::from(self.last_position),
+            vector![total_displacement.x, total_displacement.y, total_displacement.z],
+            |collision| collisions.push(collision),
+        );
+
+        // update character rigid body with the new translation.
+        if let Some(body) = p.get_rigid_body_mut(ch_component.0) {
+            self.last_position = vector![
+                self.last_position.x + corrected_movement.translation.x,
+                self.last_position.y + corrected_movement.translation.y,
+                self.last_position.z + corrected_movement.translation.z,
+            ];
+            body.set_next_kinematic_position(Isometry3::from(self.last_position));
+            ch_tr.translation = Physics::rapier_translation_to_glam(&self.last_position);
+            // reset vertical velocity if grounded
+            if corrected_movement.grounded {
+                self.vertical_velocity = 0.0;
+            }
+        }
+
+        // apply impulses to dynamic bodies the character collided with
+        let character_push_force = 50.0;
+        for collision in collisions {
+            if let Some(collider) = p.collider_set.get(collision.handle) {
+                if let Some(rb_handle) = collider.parent() {
+                    if let Some(rb) = p.rigid_body_set.get_mut(rb_handle) {
+                        if rb.body_type() == RigidBodyType::Dynamic {
+                            let push_direction = -collision.hit.normal1.into_inner();
+                            let impulse = push_direction * character_push_force * pctx.time_ctx.fixed_dt;
+                            rb.apply_impulse(impulse, true);
+                        }
+                    }
+                }
+            }
+        }
+
+        self.desired_movement = Vec3::ZERO;
+    }
+}

game/src/systems/menu.rs

@@ -0,0 +1,85 @@
+use egui::Id;
+use raidillon_app::prelude::*;
+use winit::{dpi::{LogicalPosition, Position}, keyboard::KeyCode, window::CursorGrabMode};
+
+#[derive(Default)]
+pub struct MenuSystem {
+    escape_key_held: bool,
+    /// Unoptimal solution to fix windows event delay
+    times_ran_initial_win_event: u32,
+}
+
+#[derive(Default, Eq, PartialEq, Debug)]
+pub enum MenuState {
+    Open,
+    #[default]
+    Closed,
+}
+
+impl System for MenuSystem {
+    fn load_world(&mut self, res: &mut EngineResources, scene: &mut Scene) {
+        scene.world.spawn((MenuState::Closed,));
+    }
+
+    fn frame_update(&mut self, res: &mut EngineResources, scene: &mut Scene) {
+        // Windows won't register some events in the first miliseconds after initialization
+        if self.times_ran_initial_win_event < 20 {
+            let window = res.get::<PlatformContext>().unwrap().window.lock().unwrap();
+            window.set_cursor_grab(CursorGrabMode::Confined).or_else(|_| window.set_cursor_grab(CursorGrabMode::Locked));
+            window.set_cursor_visible(false);
+            self.times_ran_initial_win_event += 1
+        }
+
+        let mut egui_queue = res.get::<PlatformContext>().unwrap().egui_queue.borrow_mut();
+        egui_queue.queue(|egui_ctx| {
+            egui::Area::new(Id::new("esc to pause"))
+                .anchor(egui::Align2::RIGHT_TOP, [-10.0, 10.0])
+                .show(egui_ctx, |ui| {
+                    ui.label(
+                        egui::RichText::new("ESC to pause").size(24.0).color(egui::Color32::BLACK)
+                    );
+                });
+        });
+    }
+
+
+    fn handle_event(&mut self, res: &mut EngineResources, scene: &mut Scene) {
+        // The menu is toggled by pressing the escape key
+        let input = res.get::<InputState>().unwrap();
+        if input.key_held(KeyCode::Escape) {
+            if self.escape_key_held { return }
+            self.toggle_menu(res, scene);
+            self.escape_key_held = true;
+        } else {
+            self.escape_key_held = false;
+        }
+    }
+}
+
+impl MenuSystem {
+    fn toggle_menu(&mut self, res: &mut EngineResources, scene: &mut Scene) {
+        let q = scene.world.query_mut::<(&mut MenuState)>();
+        let (menu_ent, menu_state) = q
+            .into_iter()
+            .next()
+            .unwrap();
+
+        let pctx = res.get::<PlatformContext>().unwrap();
+        let window = pctx.window.lock().unwrap();
+
+        match *menu_state {
+            MenuState::Open => {
+                *menu_state = MenuState::Closed;
+                window.set_cursor_grab(CursorGrabMode::Confined).or_else(|_| window.set_cursor_grab(CursorGrabMode::Locked));
+                window.set_cursor_visible(false);
+                pctx.should_egui_receive_input_events.set(false);
+            },
+            MenuState::Closed => {
+                *menu_state = MenuState::Open;
+                window.set_cursor_grab(CursorGrabMode::None);
+                window.set_cursor_visible(true);
+                pctx.should_egui_receive_input_events.set(true);
+            },
+        }
+    }
+}

game/src/systems/mod.rs

@@ -0,0 +1,15 @@
+mod physics;
+mod physics_debug;
+mod kinematic_character_controller;
+mod keybinds;
+mod menu;
+pub mod debug_camera;
+pub mod common;
+mod display_settings;
+
+pub use physics::PhysicsSystem;
+pub use physics_debug::PhysicsDebugSystem;
+pub use kinematic_character_controller::KinematicCharacterController;
+pub use keybinds::KeybindsSystem;
+pub use menu::MenuSystem;
+pub use display_settings::DisplaySettings;

game/src/systems/physics.rs

@@ -0,0 +1,30 @@
+use raidillon_app::prelude::*;
+
+/// Do physics calculations and apply to world.
+#[derive(Default)]
+pub struct PhysicsSystem;
+
+impl System for PhysicsSystem {
+    fn load_world(&mut self, res: &mut EngineResources, scene: &mut Scene) {
+        let p = Physics::default();
+        scene.resources.insert(p);
+    }
+
+    fn fixed_update(&mut self, res: &mut EngineResources, scene: &mut Scene) {
+        let pctx = res.get::<PlatformContext>().expect("PlatformContext missing").clone();
+        let physics = scene.resources.get_mut::<Physics>().expect("Physics missing");
+        physics.step(pctx.time_ctx.fixed_dt);
+
+        // apply calculations to dynamic bodies
+        let mut query = scene.world.query::<(&mut Transform, &RigidBodyComponent)>();
+        for (_ent, (tr, rb_component)) in query.iter() {
+            if let Some(body) = physics.get_rigid_body(rb_component.0) {
+                let pos = body.position();
+                let translation = Physics::rapier_translation_to_glam(&pos.translation.vector);
+                let rotation = Physics::rapier_rotation_to_glam(&pos.rotation);
+                tr.translation = translation;
+                tr.rotation = rotation;
+            }
+        }
+    }
+}

game/src/systems/physics_debug.rs

@@ -0,0 +1,35 @@
+use raidillon_app::prelude::*;
+
+/// renders aabb wireframes for all physics colliders
+#[derive(Default)]
+pub struct PhysicsDebugSystem;
+
+impl System for PhysicsDebugSystem {
+    fn frame_update(&mut self, res: &mut EngineResources, scene: &mut Scene) {
+        let pctx = res.get::<PlatformContext>().expect("PlatformContext missing").clone();
+
+        let mut debug_wireframes = pctx.debug_wireframes.borrow_mut();
+        if !debug_wireframes.enabled {
+            return;
+        }
+
+        let physics = match scene.resources.get::<Physics>() {
+            Some(p) => p,
+            None => return,
+        };
+
+        let color = [1.0, 0.0, 0.0, 1.0];
+
+        for (_, collider) in physics.collider_set.iter() {
+            let aabb = collider.compute_aabb();
+            let min = aabb.mins;
+            let max = aabb.maxs;
+
+            debug_wireframes.add_box(
+                [min.x, min.y, min.z],
+                [max.x, max.y, max.z],
+                color,
+            );
+        }
+    }
+}

glium_platform/Cargo.toml

@@ -6,7 +6,7 @@ edition = "2024"
 [dependencies]
 anyhow = "1.0.98"
 glam = "0.30.5"
-glium = { version = "0.35.0", features = ["glutin_backend", "simple_window_builder"] }
+glium = { version = "0.36.0", features = ["glutin_backend", "simple_window_builder"] }
 gltf = { version = "1.4.1", features = ["import", "utils", "KHR_texture_transform"] }
 raidillon_platform = { path = "../platform" }
 raidillon_core = { path = "../core" }
@@ -15,6 +15,7 @@ raidillon_ecs = { path = "../ecs" }
 raidillon_engine = { path = "../engine" }
 winit = "0.30.12"
 indexmap = "2.10.0"
-imgui = "0.12.0"
-imgui-winit-support = "0.13.0"
-imgui-glium-renderer = "0.13.0"
+exr = "1.73.0"
+image = { version = "0.25.8", default-features = false, features = ["exr"] }
+egui = "0.33.2"
+egui_glium = { version = "0.31.1", git = "https://github.com/reo6/egui_glium.git" }

glium_platform/src/assets.rs

@@ -12,7 +12,7 @@ use raidillon_assets::model_manager::ModelID;
 
 /// Glium platform asset manager implementation.
 pub struct GliumAssetManager {
-    pub models: HashMap<ModelID, Model>,
+    pub models: HashMap<ModelID, Vec<Model>>,
     facade: Box<dyn Facade>,
 }
 
@@ -28,8 +28,8 @@ impl GliumAssetManager {
 
 impl ModelManager for GliumAssetManager {
     fn load_gltf(&mut self, id: ModelID, path: &Path) {
-        let model = load_gltf(path, self.facade.as_ref()).unwrap();
-        self.models.insert(id, model);
+        let models = load_gltf(path, self.facade.as_ref()).unwrap();
+        self.models.insert(id, models);
     }
 
     fn unload_model(&mut self, id: ModelID) {
@@ -48,6 +48,6 @@ impl ModelManager for GliumAssetManager {
     // }
 
     fn get_model(&self, id: &ModelID) -> Option<&dyn Any> {
-        self.models.get(id).map(|model| model as &dyn Any)
+        self.models.get(id).map(|models| models as &dyn Any)
     }
 }

glium_platform/src/gltf_loader.rs

@@ -1,4 +1,4 @@
-use anyhow::{Context, Result};
+use anyhow::{bail, Context, Result};
 use glium::{backend::Facade, IndexBuffer, VertexBuffer};
 use glium::index::PrimitiveType;
 use std::{fmt::Debug, path::Path};
@@ -8,31 +8,16 @@ use glium::uniforms::{SamplerWrapFunction, MinifySamplerFilter, MagnifySamplerFi
 use gltf::image::Format as GltfFormat;
 use glam::Vec2;
 
-/// Load a glTF 2.0 file from disk and upload the first primitive to the GPU.
-pub fn load_gltf<P>(path: P, facade: &dyn Facade) -> Result<Model>
+/// Load a glTF 2.0 file from disk and upload all primitives to the GPU.
+///
+/// Returns one [`Model`] per glTF primitive (across all meshes).
+pub fn load_gltf<P>(path: P, facade: &dyn Facade) -> Result<Vec<Model>>
 where
     P: AsRef<Path> + Debug,
 {
     // -- parse the asset & bring buffer blobs into memory --
     let (doc, buffers, images) = gltf::import(path.as_ref()).context("failed to import glTF file")?;
 
-    // -- grab the very first mesh / primitive --
-    let mesh      = doc.meshes().next().context("glTF has no meshes")?;
-    let primitive = mesh.primitives().next().context("mesh has no primitives")?;
-
-    // ---------- MATERIAL ----------
-    let mut mat = Material::default();
-
-    let mat_idx  = primitive.material().index().context("primitive has no material")?;
-    let material = doc.materials().nth(mat_idx).unwrap();
-    let pbr      = material.pbr_metallic_roughness();
-
-    // Factors --------------------------------------------------
-    mat.base_color_factor = pbr.base_color_factor();
-    mat.metal_factor      = pbr.metallic_factor();
-    mat.roughness_factor  = pbr.roughness_factor();
-    mat.emissive_factor   = material.emissive_factor();
-
     // Helper to update sampler settings from glTF sampler
     fn update_sampler(mat: &mut Material, t: &gltf::texture::Texture<'_>) {
         let sampler_info = t.sampler();
@@ -64,64 +49,92 @@ where
         }
     }
 
-    // Base-color texture (sRGB)
-    if let Some(info) = pbr.base_color_texture() {
-        update_sampler(&mut mat, &info.texture());
-        let view = info.texture().source().index();
-        mat.base_color = Some(glium_srgb_texture(facade, &images[view])?);
-    }
+    let mut out: Vec<Model> = Vec::new();
 
-    // Metallic-Roughness (linear)
-    if let Some(info) = pbr.metallic_roughness_texture() {
-        update_sampler(&mut mat, &info.texture());
-        let view = info.texture().source().index();
-        mat.metallic_roughness = Some(glium_linear_texture(facade, &images[view])?);
-    }
+    for mesh in doc.meshes() {
+        for primitive in mesh.primitives() {
+            // ---------- MATERIAL ----------
+            let mut mat = Material::default();
+            let material = primitive.material();
+            let pbr = material.pbr_metallic_roughness();
 
-    // Normal map (linear)
-    if let Some(info) = primitive.material().normal_texture() {
-        update_sampler(&mut mat, &info.texture());
-        let view = info.texture().source().index();
-        mat.normal = Some(glium_linear_texture(facade, &images[view])?);
-    }
+            // Factors --------------------------------------------------
+            mat.base_color_factor = pbr.base_color_factor();
+            mat.metal_factor = pbr.metallic_factor();
+            mat.roughness_factor = pbr.roughness_factor();
+            mat.emissive_factor = material.emissive_factor();
 
-    // Occlusion (linear)
-    if let Some(info) = primitive.material().occlusion_texture() {
-        update_sampler(&mut mat, &info.texture());
-        let view = info.texture().source().index();
-        mat.occlusion = Some(glium_linear_texture(facade, &images[view])?);
-    }
+            // Base-color texture (sRGB)
+            if let Some(info) = pbr.base_color_texture() {
+                update_sampler(&mut mat, &info.texture());
+                let view = info.texture().source().index();
+                mat.base_color = Some(glium_srgb_texture(facade, &images[view])?);
+            }
 
-    // Emissive (sRGB)
-    if let Some(info) = primitive.material().emissive_texture() {
-        update_sampler(&mut mat, &info.texture());
-        let view = info.texture().source().index();
-        mat.emissive = Some(glium_srgb_texture(facade, &images[view])?);
-    }
+            // Metallic-Roughness (linear)
+            if let Some(info) = pbr.metallic_roughness_texture() {
+                update_sampler(&mut mat, &info.texture());
+                let view = info.texture().source().index();
+                mat.metallic_roughness = Some(glium_linear_texture(facade, &images[view])?);
+            }
 
-    // KHR_texture_transform
-    if let Some(tex) = pbr.base_color_texture() {
-        if let Some(xform) = tex.texture_transform() {
-            mat.uv_offset = Vec2::new(xform.offset()[0], xform.offset()[1]);
-            mat.uv_scale  = Vec2::new(xform.scale()[0],  xform.scale()[1]);
+            // Normal map (linear)
+            if let Some(info) = material.normal_texture() {
+                update_sampler(&mut mat, &info.texture());
+                let view = info.texture().source().index();
+                mat.normal = Some(glium_linear_texture(facade, &images[view])?);
+            }
+
+            // Occlusion (linear)
+            if let Some(info) = material.occlusion_texture() {
+                update_sampler(&mut mat, &info.texture());
+                let view = info.texture().source().index();
+                mat.occlusion = Some(glium_linear_texture(facade, &images[view])?);
+            }
+
+            // Emissive (sRGB)
+            if let Some(info) = material.emissive_texture() {
+                update_sampler(&mut mat, &info.texture());
+                let view = info.texture().source().index();
+                mat.emissive = Some(glium_srgb_texture(facade, &images[view])?);
+            }
+
+            // KHR_texture_transform (base color only, for now)
+            if let Some(tex) = pbr.base_color_texture() {
+                if let Some(xform) = tex.texture_transform() {
+                    mat.uv_offset = Vec2::new(xform.offset()[0], xform.offset()[1]);
+                    mat.uv_scale = Vec2::new(xform.scale()[0], xform.scale()[1]);
+                }
+            }
+
+            // ---- Vertex/index data ----
+            let reader = primitive.reader(|buf| Some(&buffers[buf.index()].0));
+
+            let positions: Vec<[f32; 3]> = reader.read_positions().context("missing POSITION")?.collect();
+            let normals: Vec<[f32; 3]> = reader.read_normals().context("missing NORMAL")?.collect();
+            let tex_coords: Vec<[f32; 2]> = reader
+                .read_tex_coords(0)
+                .map(|tc| tc.into_f32().collect())
+                .unwrap_or_else(|| vec![[0.0, 0.0]; positions.len()]);
+            let indices: Vec<u32> = reader.read_indices().context("missing indices")?.into_u32().collect();
+
+            // Interleave
+            let vertices: Vec<Vertex> = (0..positions.len())
+                .map(|i| Vertex { position: positions[i], normal: normals[i], tex_coords: tex_coords[i] })
+                .collect();
+
+            let vbuf = VertexBuffer::immutable(facade, &vertices)?;
+            let ibuf = IndexBuffer::immutable(facade, PrimitiveType::TrianglesList, &indices)?;
+
+            out.push(Model { mesh: Mesh { vbuf, ibuf }, material: mat });
         }
     }
 
-    // ---- Vertex/index data ----
-    let reader = primitive.reader(|buf| Some(&buffers[buf.index()].0));
+    if out.is_empty() {
+        bail!("glTF has no mesh primitives");
+    }
 
-    let positions: Vec<[f32; 3]> = reader.read_positions().context("missing POSITION")?.collect();
-    let normals:   Vec<[f32; 3]> = reader.read_normals().context("missing NORMAL")?.collect();
-    let tex_coords: Vec<[f32; 2]> = reader.read_tex_coords(0).map(|tc| tc.into_f32().collect()).unwrap_or_else(|| vec![[0.0, 0.0]; positions.len()]);
-    let indices:   Vec<u32> = reader.read_indices().context("missing indices")?.into_u32().collect();
-
-    // Interleave
-    let vertices: Vec<Vertex> = (0..positions.len()).map(|i| Vertex { position: positions[i], normal: normals[i], tex_coords: tex_coords[i] }).collect();
-
-    let vbuf = VertexBuffer::immutable(facade, &vertices)?;
-    let ibuf = IndexBuffer ::immutable(facade, PrimitiveType::TrianglesList, &indices)?;
-
-    Ok(Model { mesh: Mesh { vbuf, ibuf }, material: mat })
+    Ok(out)
 }
 
 /// Linear-space texture (RGBA8) from glTF image data.

glium_platform/src/platform.rs

@@ -1,6 +1,7 @@
-use std::cell::RefCell;
+use std::cell::{RefCell, Cell};
 use std::rc::Rc;
-use raidillon_platform::{Platform, PlatformContext};
+use std::sync::{Arc, Mutex, RwLock};
+use raidillon_platform::{Platform, PlatformContext, TimeContext, DebugWireframes, DebugWireframesRef};
 use glium::backend::glutin::Display;
 use glium::backend::glutin::SimpleWindowBuilder;
 use glium::glutin::surface::WindowSurface;
@@ -8,23 +9,33 @@ use glium::winit::event_loop::EventLoop;
 use glium::winit::window::Window;
 use glium::Surface;
 use crate::system::{RenderingContext, RenderingSystemManager};
-use winit::event::{Event, WindowEvent};
+use winit::event::{DeviceEvent, Event, WindowEvent};
 use raidillon_assets::ModelManagerRef;
 use raidillon_core::engine::EngineTrait;
-use crate::render::debug_ui::ImguiBridge;
-use crate::render::BasicMeshRenderingSystem;
+use raidillon_core::time;
+use raidillon_core::time::Time;
+use crate::render::{BasicMeshRenderingSystem, DebugWireframeRenderingSystem, EguiRenderer, SkyboxRenderingSystem};
 use crate::GliumAssetManager;
+use glam::Vec3;
+use winit::event::DeviceEvent::MouseMotion;
+use raidillon_core::EguiQueue;
+use raidillon_platform::settings::{Settings, default_config_path};
 
-pub struct GliumPlatform<E: EngineTrait> {
+pub struct GliumPlatform<E: EngineTrait<PlatformCtx = PlatformContext>> {
     event_loop: EventLoop<()>,
-    window: Window,
+    window: Arc<Mutex<Window>>,
     display: Display<WindowSurface>,
     rendering_system_manager: RenderingSystemManager,
     asset_manager: ModelManagerRef,
     engine: E,
+    time: time::Time,
+    egui_queue: Rc<RefCell<EguiQueue>>,
+    settings: Arc<RwLock<Settings>>,
+    debug_wireframes: DebugWireframesRef,
+    should_egui_receive_input_events: Rc<Cell<bool>>,
 }
 
-impl<E: EngineTrait> Platform<E> for GliumPlatform<E> {
+impl<E: EngineTrait<PlatformCtx = PlatformContext>> Platform<E> for GliumPlatform<E> {
     fn initialize(mut engine: E, title: String, width: u32, height: u32) -> Self {
         let event_loop = glium::winit::event_loop::EventLoop::builder()
             .build()
@@ -38,9 +49,26 @@ impl<E: EngineTrait> Platform<E> for GliumPlatform<E> {
         let asset_manager: ModelManagerRef = Rc::new(RefCell::new(Box::new(GliumAssetManager::new(Box::new(display.clone())))));
         let mut rendering_system_manager = RenderingSystemManager::new();
 
-        // Install rendering systems
-        rendering_system_manager.add::<BasicMeshRenderingSystem>(&display, &window);
-        rendering_system_manager.add::<ImguiBridge>(&display, &window);
+        let time_cfg = time::Config::default();
+        let time = time::Time::new(time_cfg);
+
+        let window = Arc::new(Mutex::new(window));
+
+        // Install rendering systems in order
+        rendering_system_manager.add::<SkyboxRenderingSystem>(&display, window.clone(), &event_loop);
+        rendering_system_manager.add::<BasicMeshRenderingSystem>(&display, window.clone(), &event_loop);
+        rendering_system_manager.add::<DebugWireframeRenderingSystem>(&display, window.clone(), &event_loop);
+        rendering_system_manager.add::<EguiRenderer>(&display, window.clone(), &event_loop);
+
+        let egui_queue = Rc::new(RefCell::new(EguiQueue::new()));
+
+        let settings = Arc::new(
+            RwLock::new(
+                Settings::load_or_default(default_config_path()).unwrap()
+            )
+        );
+        let debug_wireframes = Rc::new(RefCell::new(DebugWireframes::new()));
+        let should_egui_receive_input_events = Rc::new(Cell::new(false));
 
         Self {
             event_loop,
@@ -49,23 +77,45 @@ impl<E: EngineTrait> Platform<E> for GliumPlatform<E> {
             rendering_system_manager,
             asset_manager,
             engine,
+            time,
+            egui_queue,
+            settings,
+            debug_wireframes,
+            should_egui_receive_input_events,
         }
     }
 
     fn run(mut self) {
-        let (w, h): (u32, u32) = self.window.inner_size().into();
+        let (w, h): (u32, u32) = match self.window.lock() {
+            Ok(window) => window.inner_size().into(),
+            Err(_) => (0, 0), // fallback values
+        };
         let ctx = PlatformContext {
             current_event: Event::AboutToWait,
             asset_manager: self.asset_manager.clone(),
             frame_width: w as f32,
             frame_height: h as f32,
+            time_ctx: self.construct_time_ctx(),
+            window: self.window.clone(),
+            egui_queue: self.egui_queue.clone(),
+            settings: self.settings.clone(),
+            debug_wireframes: self.debug_wireframes.clone(),
+            should_egui_receive_input_events: self.should_egui_receive_input_events.clone(),
         };
         self.engine.initialize(ctx.clone());
+        self.settings.read().unwrap().display_settings.apply(&*self.window.lock().unwrap());
+
         let _ = &self.event_loop.run(move |event, el| {
+            let settings_handle = self.settings.read().unwrap();
+            if settings_handle.display_settings.dirty {
+                settings_handle.display_settings.apply(&*self.window.lock().unwrap());
+            }
+            drop(settings_handle);
+
             self.rendering_system_manager
                 .systems
                 .values_mut()
-                .for_each(|system| system.handle_event(&mut self.window, event.clone()));
+                .for_each(|system| system.handle_event(self.window.clone(), event.clone()));
 
             let mut ctx2 = ctx.clone();
             ctx2.current_event = event.clone();
@@ -73,42 +123,79 @@ impl<E: EngineTrait> Platform<E> for GliumPlatform<E> {
 
             match event {
                 Event::WindowEvent { event, .. } => match event {
+                    WindowEvent::Resized(size) => {
+                        if size.width > 0 && size.height > 0 {
+                            self.display.resize((size.width, size.height));
+                        }
+                    },
                     WindowEvent::CloseRequested => {
                         // TODO: Run uninitialize on renderer and engine
+                        self.settings.read().unwrap().save_to_file(default_config_path());
                         el.exit();
                     },
                     WindowEvent::RedrawRequested => {
                         let mut target = self.display.draw();
                         target.clear_color_and_depth((0.1, 0.1, 0.15, 1.0), 1.0);
-                        let (scene_mut, debug_ui_buffer) = self.engine.scene_and_debug_ui_buffer_mut();
+                        let scene = self.engine.current_scene();
                         let mut context = RenderingContext {
-                            scene: scene_mut,
+                            scene,
                             target: &mut target,
+                            display: &self.display,
                             asset_manager: self.asset_manager.clone(),
-                            window: &mut self.window,
-                            debug_ui_buffer,
+                            window: self.window.clone(),
+                            egui_queue: self.egui_queue.clone(),
+                            debug_wireframes: self.debug_wireframes.clone(),
+                            env_light_dir: Vec3::new(0.0, -1.0, 0.0),
+                            should_egui_receive_input_events: self.should_egui_receive_input_events.clone(),
                         };
 
                         self.rendering_system_manager
                             .systems
                             .values_mut()
                             .for_each(|system| system.render(&mut context));
+
+                        // clear debug wireframes after rendering
+                        self.debug_wireframes.borrow_mut().clear();
+
                         target.finish().unwrap();
                     }
                     _ => {},
                 },
                 Event::AboutToWait => {
+                    let plan = self.time.begin_frame_blocking();
+
                     let mut ctx2 = ctx.clone();
-                    ctx2.current_event = event.clone();
-                    self.engine.update(ctx2);
+                    ctx2.time_ctx = TimeContext {
+                        frame_dt: self.time.frame_dt_seconds(),
+                        fixed_dt: self.time.fixed_dt_seconds(),
+                        alpha: self.time.alpha(),
+                    };
+                    ctx2.current_event = Event::AboutToWait;
+
+                    for _ in 0..plan.updates {
+                        self.engine.fixed_update(ctx2.clone());
+                    }
+
+                    self.engine.frame_update(ctx2.clone());
+
                     self.rendering_system_manager
                         .systems
                         .values_mut()
-                        .for_each(|system| system.prepare_frame(&mut self.window));
-                    self.window.request_redraw();
+                        .for_each(|system| system.prepare_frame(self.window.clone()));
+                    self.window.lock().unwrap().request_redraw();
                 }
                 _ => {},
             }
         });
     }
 }
+
+impl<E: EngineTrait<PlatformCtx = PlatformContext>> GliumPlatform<E> {
+    fn construct_time_ctx(&self) -> TimeContext {
+        TimeContext {
+            frame_dt: self.time.frame_dt_seconds(),
+            fixed_dt: self.time.fixed_dt_seconds(),
+            alpha: self.time.alpha(),
+        }
+    }
+}

glium_platform/src/render/basic.rs

@@ -1,4 +1,5 @@
 use std::any::Any;
+use std::sync::{Arc, Mutex};
 use glium::{uniform, Display, Program, Surface};
 use glium::glutin::surface::WindowSurface;
 use glium::texture::{RawImage2d, SrgbTexture2d};
@@ -8,6 +9,8 @@ use raidillon_assets::include_shader;
 pub use raidillon_platform::Camera;
 use glam::Vec3;
 use glium::uniforms::{MagnifySamplerFilter, MinifySamplerFilter, SamplerWrapFunction};
+use winit::event::Event;
+use winit::event_loop::EventLoop;
 use raidillon_ecs::{Transform, ModelID};
 use raidillon_ecs::components::ModelHandle;
 use crate::model::Model;
@@ -20,7 +23,7 @@ pub struct BasicMeshRenderingSystem {
 }
 
 impl RenderingSystem for BasicMeshRenderingSystem {
-    fn initialize(display: &Display<WindowSurface>, _window: &glium::winit::window::Window) -> Self {
+    fn initialize(display: &Display<WindowSurface>, _window: Arc<Mutex<glium::winit::window::Window>>, event_loop: &EventLoop<()>) -> Self {
         const VERT_SRC: &str = include_shader!("gl_textured.vert");
         const FRAG_SRC: &str = include_shader!("gl_textured.frag");
 
@@ -55,14 +58,12 @@ impl RenderingSystem for BasicMeshRenderingSystem {
             }
         };
 
-        // Direction from the light source (0,+Y) towards the scene.
-        let light_dir: Vec3 = Vec3::new(0.0, -1.0, 0.0).normalize();
+        // Use HDR-derived environment light direction if provided, otherwise default to downward
+        let light_dir_world: Vec3 = if ctx.env_light_dir.length_squared() > 0.0 { ctx.env_light_dir.normalize() } else { Vec3::new(0.0, -1.0, 0.0) };
 
-        // let asset_manager = ctx.asset_manager.borrow();
-        // let any_ref: &dyn Any = &**asset_manager;
-        // if let Some(glium_manager) = any_ref.downcast_ref::<GliumAssetManager>() {
-        //     &glium_manager.models;
-        // }
+        // Transform light direction to view space (normals/positions are in view space)
+        let view_mat3 = glam::Mat3::from_mat4(cam.view());
+        let light_dir_view = (view_mat3 * light_dir_world).normalize();
 
         let asset_manager = ctx.asset_manager.borrow();
 
@@ -72,41 +73,43 @@ impl RenderingSystem for BasicMeshRenderingSystem {
                 _ => continue,
             };
 
-            let model = match model.downcast_ref::<Model>() {
-                Some(model) => model,
+            let models = match model.downcast_ref::<Vec<Model>>() {
+                Some(models) => models,
                 None => continue,
             };
 
-            let mesh = &model.mesh;
-            let mat = &model.material;
+            for model in models {
+                let mesh = &model.mesh;
+                let mat = &model.material;
 
-            let tex_ref: &SrgbTexture2d = mat.base_color.as_ref().unwrap_or(&self.white_tex);
+                let tex_ref: &SrgbTexture2d = mat.base_color.as_ref().unwrap_or(&self.white_tex);
 
-            let mut sampler = tex_ref.sampled();
-            sampler = sampler.wrap_function(SamplerWrapFunction::Repeat);
-            sampler = sampler.minify_filter(MinifySamplerFilter::Linear);
-            sampler = sampler.magnify_filter(MagnifySamplerFilter::Linear);
+                let mut sampler = tex_ref.sampled();
+                sampler = sampler.wrap_function(SamplerWrapFunction::Repeat);
+                sampler = sampler.minify_filter(MinifySamplerFilter::Linear);
+                sampler = sampler.magnify_filter(MagnifySamplerFilter::Linear);
 
-            let c = mat.base_color_factor;
+                let c = mat.base_color_factor;
 
-            let uniforms = uniform! {
-                model:      tr.matrix().to_cols_array_2d(),
-                view:       cam.view().to_cols_array_2d(),
-                projection: cam.projection().to_cols_array_2d(),
-                u_light:    [light_dir.x, light_dir.y, light_dir.z],
-                tex:        sampler,
-                color:      [c[0], c[1], c[2]],
-                uv_offset:  [mat.uv_offset.x, mat.uv_offset.y],
-                uv_scale:   [mat.uv_scale.x,  mat.uv_scale.y],
-            };
+                let uniforms = uniform! {
+                    model:      tr.matrix().to_cols_array_2d(),
+                    view:       cam.view().to_cols_array_2d(),
+                    projection: cam.projection().to_cols_array_2d(),
+                    u_light:    [light_dir_view.x, light_dir_view.y, light_dir_view.z],
+                    tex:        sampler,
+                    color:      [c[0], c[1], c[2]],
+                    uv_offset:  [mat.uv_offset.x, mat.uv_offset.y],
+                    uv_scale:   [mat.uv_scale.x,  mat.uv_scale.y],
+                };
 
-            ctx.target.draw(
-                &mesh.vbuf,
-                &mesh.ibuf,
-                &self.program,
-                &uniforms,
-                &self.params,
-            ).unwrap();
+                ctx.target.draw(
+                    &mesh.vbuf,
+                    &mesh.ibuf,
+                    &self.program,
+                    &uniforms,
+                    &self.params,
+                ).unwrap();
+            }
         }
     }
 }

glium_platform/src/render/debug_ui.rs

@@ -1,68 +0,0 @@
-use std::time::Instant;
-use glium::Display;
-use glium::glutin::surface::WindowSurface;
-use imgui::{Context as ImguiContext};
-use imgui_winit_support::{HiDpiMode, WinitPlatform};
-use imgui_glium_renderer::Renderer as ImguiGliumRenderer;
-use winit::window::Window;
-use winit::event::Event;
-use glium::Frame;
-use crate::RenderingSystem;
-use crate::system::RenderingContext;
-
-pub struct ImguiBridge {
-    imgui: ImguiContext,
-    platform: WinitPlatform,
-    renderer: ImguiGliumRenderer,
-    last_frame: Instant,
-    rendered_this_frame: bool,
-}
-
-impl RenderingSystem for ImguiBridge {
-    fn handle_event(&mut self, window: &mut Window, event: Event<()>) {
-        self.platform.handle_event(self.imgui.io_mut(), window, &event);
-    }
-
-    fn prepare_frame(&mut self, window: &mut Window) {
-        self.rendered_this_frame = false;
-        let now = Instant::now();
-        self.imgui.io_mut().update_delta_time(now - self.last_frame);
-        self.last_frame = now;
-        self.platform
-            .prepare_frame(self.imgui.io_mut(), window)
-            .expect("Failed to prepare frame");
-    }
-
-    fn render(&mut self, ctx: &mut RenderingContext) {
-        if self.rendered_this_frame { return; }
-        self.rendered_this_frame = true;
-
-        let ui = self.imgui.frame();
-        ctx.debug_ui_buffer.borrow().write_buffer(&ui);
-
-        self.platform.prepare_render(&ui, ctx.window);
-        let draw_data = self.imgui.render();
-        if draw_data.total_vtx_count == 0 && draw_data.total_idx_count == 0 {
-            return;
-        }
-
-        self.renderer.render(ctx.target, draw_data).expect("imgui rendering failed");
-    }
-
-    fn initialize(display: &Display<WindowSurface>, window: &Window) -> Self {
-        let mut imgui = ImguiContext::create();
-        imgui.set_ini_filename(None);
-        let mut platform = WinitPlatform::new(&mut imgui);
-        platform.attach_window(imgui.io_mut(), window, HiDpiMode::Default);
-        imgui.fonts().add_font(&[imgui::FontSource::DefaultFontData { config: None }]);
-        let renderer = ImguiGliumRenderer::new(&mut imgui, display).unwrap();
-
-        Self {
-            imgui,
-            platform,
-            renderer,
-            last_frame: Instant::now(),
-            rendered_this_frame: false,
-        }
-    }
-}

glium_platform/src/render/debug_wireframe.rs

@@ -0,0 +1,80 @@
+use std::sync::{Arc, Mutex};
+use glium::{Display, Program, Surface, VertexBuffer, implement_vertex};
+use glium::glutin::surface::WindowSurface;
+use glium::index::PrimitiveType;
+use glium::uniform;
+use winit::event_loop::EventLoop;
+use raidillon_assets::include_shader;
+use crate::system::RenderingContext;
+use crate::RenderingSystem;
+pub use raidillon_platform::Camera;
+
+#[derive(Copy, Clone)]
+struct DebugVertex {
+    position: [f32; 3],
+    color: [f32; 4],
+}
+
+implement_vertex!(DebugVertex, position, color);
+
+/// renders debug wireframes from the shared buffer
+pub struct DebugWireframeRenderingSystem {
+    program: Program,
+    params: glium::DrawParameters<'static>,
+}
+
+impl RenderingSystem for DebugWireframeRenderingSystem {
+    fn initialize(display: &Display<WindowSurface>, _window: Arc<Mutex<glium::winit::window::Window>>, _event_loop: &EventLoop<()>) -> Self {
+        const VERT_SRC: &str = include_shader!("debug_wireframe.vert");
+        const FRAG_SRC: &str = include_shader!("debug_wireframe.frag");
+
+        let program = Program::from_source(display, VERT_SRC, FRAG_SRC, None).unwrap();
+
+        let params = glium::DrawParameters {
+            depth: glium::Depth {
+                test: glium::draw_parameters::DepthTest::IfLess,
+                write: false,
+                ..Default::default()
+            },
+            line_width: Some(1.0),
+            ..Default::default()
+        };
+
+        Self { program, params }
+    }
+
+    fn render(&mut self, ctx: &mut RenderingContext) {
+        let debug_wireframes = ctx.debug_wireframes.borrow();
+
+        if !debug_wireframes.enabled || debug_wireframes.vertices.is_empty() {
+            return;
+        }
+
+        let cam = match ctx.scene.world.query::<&Camera>().iter().next() {
+            Some((_, cam)) => *cam,
+            None => return,
+        };
+
+        let vertices: Vec<DebugVertex> = debug_wireframes.vertices.iter()
+            .map(|v| DebugVertex { position: v.position, color: v.color })
+            .collect();
+
+        let vbuf = match VertexBuffer::new(ctx.display, &vertices) {
+            Ok(vb) => vb,
+            Err(_) => return,
+        };
+
+        let uniforms = uniform! {
+            view: cam.view().to_cols_array_2d(),
+            projection: cam.projection().to_cols_array_2d(),
+        };
+
+        ctx.target.draw(
+            &vbuf,
+            glium::index::NoIndices(PrimitiveType::LinesList),
+            &self.program,
+            &uniforms,
+            &self.params,
+        ).ok();
+    }
+}

glium_platform/src/render/egui.rs

@@ -0,0 +1,74 @@
+use std::sync::{Arc, Mutex};
+use egui::ViewportId;
+use glium::{Display, Frame};
+use glium::glutin::surface::WindowSurface;
+use winit::window::Window;
+use crate::RenderingSystem;
+use crate::system::RenderingContext;
+use egui_glium::EguiGlium;
+use winit::event::{Event, WindowEvent};
+use winit::event_loop::EventLoop;
+use std::cell::Cell;
+use std::rc::Rc;
+
+pub struct EguiRenderer {
+    egui_glium: EguiGlium,
+    should_egui_receive_input_events: Option<Rc<Cell<bool>>>,
+}
+
+impl RenderingSystem for EguiRenderer {
+    fn initialize(display: &Display<WindowSurface>, window: Arc<Mutex<Window>>, event_loop: &EventLoop<()>) -> Self
+    where
+        Self: Sized,
+    {
+        let window = window.lock().unwrap();
+        let egui_glium = EguiGlium::new(ViewportId::ROOT, &display, &window, &event_loop);
+
+        Self { egui_glium: egui_glium, should_egui_receive_input_events: None }
+    }
+
+    fn render(&mut self, ctx: &mut RenderingContext) {
+        if self.should_egui_receive_input_events.is_none() {
+            self.should_egui_receive_input_events = Some(ctx.should_egui_receive_input_events.clone());
+        }
+
+        let window = ctx.window.lock().unwrap();
+
+        self.egui_glium.run(&window, |egui_ctx| {
+            ctx.egui_queue.borrow_mut().run(egui_ctx);
+        });
+
+        self.egui_glium.paint(ctx.display, ctx.target);
+    }
+
+    fn handle_event(&mut self, window: Arc<Mutex<Window>>, event: Event<()>) {
+        let window = window.lock().unwrap();
+        match event {
+            Event::WindowEvent { event, .. } => {
+                let should_egui_receive_input_events = match self.should_egui_receive_input_events.as_ref() {
+                    Some(v) => v.get(),
+                    None => true,
+                };
+
+                let should_send_event = if should_egui_receive_input_events {
+                    true
+                } else {
+                    !matches!(event,
+                        WindowEvent::KeyboardInput { .. } |
+                        WindowEvent::ModifiersChanged(_) |
+                        WindowEvent::CursorMoved { .. } |
+                        WindowEvent::MouseInput { .. } |
+                        WindowEvent::MouseWheel { .. } |
+                        WindowEvent::Touch(_) |
+                        WindowEvent::Ime(_)
+                    )
+                };
+
+                if should_send_event {
+                    let _ = self.egui_glium.on_event(&window, &event);
+                }
+            }
+            _ => {},
+        }
+    }
+}

glium_platform/src/render/mod.rs

@@ -1,4 +1,9 @@
 mod basic;
-pub mod debug_ui;
+mod skybox;
+mod egui;
+mod debug_wireframe;
 
 pub use basic::BasicMeshRenderingSystem;
+pub use skybox::SkyboxRenderingSystem;
+pub use egui::EguiRenderer;
+pub use debug_wireframe::DebugWireframeRenderingSystem;

glium_platform/src/render/skybox.rs

@@ -0,0 +1,157 @@
+use std::path::PathBuf;
+use std::rc::Rc;
+use std::cell::RefCell;
+use std::sync::{Arc, Mutex};
+use glium::{Display, Program, Surface, VertexBuffer, IndexBuffer, implement_vertex};
+use glium::glutin::surface::WindowSurface;
+use glium::index::PrimitiveType;
+use glium::texture::{RawImage2d, SrgbTexture2d, Texture2d};
+use glium::uniform;
+use glium::uniforms::{MagnifySamplerFilter, MinifySamplerFilter, SamplerWrapFunction};
+use glam::{Mat4, Vec2, Vec3};
+use winit::event_loop::EventLoop;
+use raidillon_assets::include_shader;
+use crate::system::RenderingContext;
+use crate::RenderingSystem;
+
+#[derive(Copy, Clone)]
+struct SkyboxVertex { position: [f32; 3] }
+implement_vertex!(SkyboxVertex, position);
+
+pub struct SkyboxRenderingSystem {
+	program: Program,
+	quad_vb: VertexBuffer<SkyboxVertex>,
+	quad_ib: IndexBuffer<u16>,
+	/// Equirectangular HDR image, tonemapped to sRGB for skybox view
+	equirect_srgb: SrgbTexture2d,
+	/// Dominant light direction estimated from HDRI
+	light_dir: Vec3,
+}
+
+impl SkyboxRenderingSystem {
+	fn build_cube(display: &Display<WindowSurface>) -> (VertexBuffer<SkyboxVertex>, IndexBuffer<u16>) {
+		// Unit cube centered at origin
+		let p = &[
+			[-1.0, -1.0, -1.0], [ 1.0, -1.0, -1.0], [ 1.0,  1.0, -1.0], [-1.0,  1.0, -1.0], // back
+			[-1.0, -1.0,  1.0], [ 1.0, -1.0,  1.0], [ 1.0,  1.0,  1.0], [-1.0,  1.0,  1.0], // front
+		];
+		let verts = vec![
+			SkyboxVertex { position: p[0] }, SkyboxVertex { position: p[1] }, SkyboxVertex { position: p[2] }, SkyboxVertex { position: p[3] }, // back
+			SkyboxVertex { position: p[4] }, SkyboxVertex { position: p[5] }, SkyboxVertex { position: p[6] }, SkyboxVertex { position: p[7] }, // front
+		];
+		let idx: [u16; 36] = [
+			// back face
+			0,1,2,  2,3,0,
+			// front face
+			4,6,5,  6,4,7,
+			// left face
+			0,3,7,  7,4,0,
+			// right face
+			1,5,6,  6,2,1,
+			// bottom face
+			0,4,5,  5,1,0,
+			// top face
+			3,2,6,  6,7,3,
+		];
+		(
+			VertexBuffer::new(display, &verts).unwrap(),
+			IndexBuffer::new(display, PrimitiveType::TrianglesList, &idx).unwrap(),
+		)
+	}
+
+	fn load_hdr_equirect_and_analyze(display: &Display<WindowSurface>, path: &std::path::Path) -> (SrgbTexture2d, Vec3) {
+		// Use image crate to decode EXR as f32 RGB
+		let dyn_img = image::ImageReader::open(path).expect("open exr").with_guessed_format().expect("guess format").decode().expect("decode exr");
+		let hdr = dyn_img.to_rgb32f();
+		let (width, height) = hdr.dimensions();
+		let width = width as usize; let height = height as usize;
+		let mut dir_accum = Vec3::ZERO;
+		let mut weight_sum = 0.0f32;
+		for y in 0..height {
+			let v = (y as f32 + 0.5) / height as f32;
+			let theta = (v - 0.5) * std::f32::consts::PI;
+			let lat_weight = theta.cos().max(0.0);
+			for x in 0..width {
+				let u = (x as f32 + 0.5) / width as f32;
+				let phi = (u - 0.5) * 2.0 * std::f32::consts::PI;
+				let px = hdr.get_pixel(x as u32, y as u32).0;
+				let rgb = Vec3::new(px[0], px[1], px[2]);
+				let lum = 0.2126*rgb.x + 0.7152*rgb.y + 0.0722*rgb.z;
+				if lum > 0.0 {
+					let dir = Vec3::new(phi.cos()*theta.cos(), theta.sin(), phi.sin()*theta.cos());
+					let w = lum * lat_weight;
+					dir_accum += dir * w;
+					weight_sum += w;
+				}
+			}
+		}
+		let mut light_dir = if weight_sum > 0.0 { dir_accum / weight_sum } else { Vec3::new(0.0, -1.0, 0.0) };
+		if light_dir.length_squared() < 1e-6 { light_dir = Vec3::new(0.0,-1.0,0.0); }
+		light_dir = light_dir.normalize();
+
+		// Tonemap to sRGB
+		let mut srgb_bytes = Vec::with_capacity(width*height*4);
+		for y in 0..height {
+			for x in 0..width {
+				let px = hdr.get_pixel(x as u32, y as u32).0;
+				let mapped = Vec3::new(px[0], px[1], px[2]) / (Vec3::new(px[0], px[1], px[2]) + Vec3::ONE);
+				let srgb = mapped.powf(1.0/2.2);
+				srgb_bytes.extend_from_slice(&[
+					(srgb.x.clamp(0.0,1.0)*255.0) as u8,
+					(srgb.y.clamp(0.0,1.0)*255.0) as u8,
+					(srgb.z.clamp(0.0,1.0)*255.0) as u8,
+					255u8,
+				]);
+			}
+		}
+		let raw = RawImage2d::from_raw_rgba(srgb_bytes, (width as u32, height as u32));
+		let tex = SrgbTexture2d::new(display, raw).unwrap();
+		(tex, light_dir)
+	}
+}
+
+impl RenderingSystem for SkyboxRenderingSystem {
+	fn initialize(display: &Display<WindowSurface>, _window: Arc<Mutex<glium::winit::window::Window>>, event_loop: &EventLoop<()>) -> Self {
+		const VERT_SRC: &str = include_shader!("skybox.vert");
+		const FRAG_SRC: &str = include_shader!("skybox.frag");
+		let program = Program::from_source(display, VERT_SRC, FRAG_SRC, None).unwrap();
+		let (quad_vb, quad_ib) = Self::build_cube(display);
+
+		// Load EXR from assets/exr
+		let manifest_dir = env!("CARGO_MANIFEST_DIR");
+		let path = std::path::Path::new(manifest_dir).join("../assets/exr/citrus_orchard_road_puresky_4k.exr");
+		let (equirect_srgb, light_dir) = Self::load_hdr_equirect_and_analyze(display, &path);
+		Self { program, quad_vb, quad_ib, equirect_srgb, light_dir }
+	}
+
+	fn render(&mut self, ctx: &mut RenderingContext) {
+		// Provide view and projection without translation for skybox
+		let cam = match ctx.scene.world.query::<&raidillon_platform::Camera>().iter().next() {
+			Some((_, cam)) => *cam,
+			None => return,
+		};
+		let mut view = cam.view();
+		// remove translation from view matrix (only orientation)
+		view.col_mut(3).x = 0.0; view.col_mut(3).y = 0.0; view.col_mut(3).z = 0.0;
+		let mut sampler = self.equirect_srgb.sampled();
+		sampler = sampler.wrap_function(SamplerWrapFunction::Repeat);
+		sampler = sampler.minify_filter(MinifySamplerFilter::Linear);
+		sampler = sampler.magnify_filter(MagnifySamplerFilter::Linear);
+
+		let uniforms = uniform! {
+			view:       view.to_cols_array_2d(),
+			projection: cam.projection().to_cols_array_2d(),
+			equirect:   sampler,
+		};
+		let params = glium::DrawParameters { depth: glium::Depth { test: glium::draw_parameters::DepthTest::IfLessOrEqual, write: false, ..Default::default() }, ..Default::default() };
+		ctx.target.draw(&self.quad_vb, &self.quad_ib, &self.program, &uniforms, &params).ok();
+
+		// Share light direction with following passes
+		ctx.env_light_dir = self.light_dir;
+	}
+}
+
+// Provide a getter for light direction for other systems
+impl SkyboxRenderingSystem {
+	pub fn light_direction(&self) -> Vec3 { self.light_dir }
+}

glium_platform/src/system.rs

@@ -1,19 +1,28 @@
 use std::any::TypeId;
 use std::cell::RefCell;
 use std::rc::Rc;
+use std::sync::{Arc, Mutex};
 use indexmap::IndexMap;
 use glium::{Display, Frame};
 use glium::glutin::surface::WindowSurface;
 use raidillon_assets::ModelManagerRef;
-use raidillon_core::DebugUIBuffer;
+use raidillon_core::{define_typemap, EguiQueue};
 use raidillon_core::scene::Scene;
+use raidillon_platform::DebugWireframesRef;
+use glam::Vec3;
+use winit::event_loop::EventLoop;
+use std::cell::Cell;
 
 pub struct RenderingContext<'a> {
     pub scene: &'a Scene,
     pub target: &'a mut Frame,
-    pub window: &'a mut glium::winit::window::Window,
+    pub window: Arc<Mutex<glium::winit::window::Window>>,
+    pub display: &'a Display<WindowSurface>,
     pub asset_manager: ModelManagerRef,
-    pub debug_ui_buffer: Rc<RefCell<DebugUIBuffer>>,
+    pub egui_queue: Rc<RefCell<EguiQueue>>,
+    pub debug_wireframes: DebugWireframesRef,
+    pub env_light_dir: Vec3,
+    pub should_egui_receive_input_events: Rc<Cell<bool>>
 }
 
 /// The internal "rendering system" trait of glium_platform.
@@ -21,17 +30,19 @@ pub struct RenderingContext<'a> {
 pub trait RenderingSystem {
     fn handle_event(
         &mut self,
-        _window: &mut glium::winit::window::Window,
+        _window: Arc<Mutex<glium::winit::window::Window>>,
         _event: winit::event::Event<()>,
     ) {
     }
-    fn prepare_frame(&mut self, _window: &mut glium::winit::window::Window) {}
+    fn prepare_frame(&mut self, _window: Arc<Mutex<glium::winit::window::Window>>) {}
     fn render(&mut self, ctx: &mut RenderingContext);
-    fn initialize(display: &Display<WindowSurface>, window: &glium::winit::window::Window) -> Self
+    fn initialize(display: &Display<WindowSurface>, window: Arc<Mutex<glium::winit::window::Window>>, event_loop: &EventLoop<()>) -> Self
     where
         Self: Sized;
 }
 
+// define_typemap!(RenderingSystemManager, RenderingSystem);
+
 pub struct RenderingSystemManager {
     pub systems: IndexMap<TypeId, Box<dyn RenderingSystem>>,
 }
@@ -43,11 +54,11 @@ impl RenderingSystemManager {
         }
     }
 
-    pub fn add<R>(&mut self, display: &Display<WindowSurface>, window: &glium::winit::window::Window)
+    pub fn add<R>(&mut self, display: &Display<WindowSurface>, window: Arc<Mutex<glium::winit::window::Window>>, event_loop: &EventLoop<()>)
     where
         R: RenderingSystem + 'static,
     {
-        let system = R::initialize(display, window);
+        let system = R::initialize(display, window, event_loop);
         self.systems.insert(TypeId::of::<R>(), Box::new(system));
     }
 

physics/Cargo.toml

@@ -0,0 +1,9 @@
+[package]
+name = "raidillon_physics"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
+rapier3d = "0.30.1"
+raidillon_ecs = { path = "../ecs" }
+glam = "0.30.8"

physics/src/lib.rs

@@ -0,0 +1,3 @@
+mod physics;
+
+pub use crate::physics::Physics;

physics/src/physics.rs

@@ -0,0 +1,82 @@
+use glam::{Quat, Vec3};
+use rapier3d::na::{Quaternion, UnitQuaternion};
+use rapier3d::prelude::*;
+use raidillon_ecs::Transform;
+
+/// Tiny wrapper around rapier3d.
+pub struct Physics {
+    pub rigid_body_set: RigidBodySet,
+    pub collider_set: ColliderSet,
+    physics_pipeline: PhysicsPipeline,
+    island_manager: IslandManager,
+    pub broad_phase: DefaultBroadPhase,
+    pub narrow_phase: NarrowPhase,
+    impulse_joint_set: ImpulseJointSet,
+    multibody_joint_set: MultibodyJointSet,
+    ccd_solver: CCDSolver,
+    gravity: Vector<f32>,
+    integration_parameters: IntegrationParameters,
+}
+
+impl Default for Physics {
+    fn default() -> Self {
+        Self {
+            gravity: vector![0.0, -9.81, 0.0],
+            rigid_body_set: Default::default(),
+            collider_set: Default::default(),
+            physics_pipeline: Default::default(),
+            island_manager: Default::default(),
+            broad_phase: Default::default(),
+            narrow_phase: Default::default(),
+            impulse_joint_set: Default::default(),
+            multibody_joint_set: Default::default(),
+            ccd_solver: Default::default(),
+            integration_parameters: Default::default(),
+        }
+    }
+}
+
+impl Physics {
+    pub fn step(&mut self, dt: f32) {
+        self.integration_parameters.dt = dt;
+        self.physics_pipeline.step(
+            &self.gravity,
+            &self.integration_parameters,
+            &mut self.island_manager,
+            &mut self.broad_phase,
+            &mut self.narrow_phase,
+            &mut self.rigid_body_set,
+            &mut self.collider_set,
+            &mut self.impulse_joint_set,
+            &mut self.multibody_joint_set,
+            &mut self.ccd_solver,
+            &(),
+            &(),
+        );
+    }
+
+    pub fn add_rigid_body(&mut self, kind: RigidBodyType, transform: Transform, collider: Collider) -> RigidBodyHandle {
+        let rb = RigidBodyBuilder::new(kind)
+            .translation(vector![transform.translation.x, transform.translation.y, transform.translation.z])
+            .build();
+        let rb_handle = self.rigid_body_set.insert(rb);
+        self.collider_set.insert_with_parent(collider, rb_handle, &mut self.rigid_body_set);
+        rb_handle
+    }
+
+    pub fn get_rigid_body(&self, handle: RigidBodyHandle) -> Option<&RigidBody> {
+        self.rigid_body_set.get(handle)
+    }
+
+    pub fn get_rigid_body_mut(&mut self, handle: RigidBodyHandle) -> Option<&mut RigidBody> {
+        self.rigid_body_set.get_mut(handle)
+    }
+
+    pub fn rapier_translation_to_glam(v: &Vector<f32>) -> Vec3 {
+        Vec3::new(v.x, v.y, v.z)
+    }
+
+    pub fn rapier_rotation_to_glam(r: &UnitQuaternion<f32>) -> Quat {
+        Quat::from_xyzw(r.i, r.j, r.k, r.w)
+    }
+}

platform/Cargo.toml

@@ -8,3 +8,5 @@ winit = "0.30.12"
 raidillon_core = { path = "../core" }
 raidillon_assets = { path = "../asset" }
 glam = "0.30.5"
+serde = { version = "1.0.228", features = ["derive"] }
+toml = "0.9.8"

platform/src/context.rs

@@ -0,0 +1,86 @@
+use std::cell::Cell;
+use std::{cell::RefCell, rc::Rc};
+use std::sync::{Arc, Mutex, RwLock};
+use winit::event::Event;
+use raidillon_assets::ModelManagerRef;
+use raidillon_core::EguiQueue;
+use crate::settings::Settings;
+
+/// a single debug wireframe vertex with position and color
+#[derive(Clone, Copy)]
+pub struct DebugWireframeVertex {
+    pub position: [f32; 3],
+    pub color: [f32; 4],
+}
+
+/// shared buffer for debug wireframe rendering
+#[derive(Clone, Default)]
+pub struct DebugWireframes {
+    pub vertices: Vec<DebugWireframeVertex>,
+    pub enabled: bool,
+}
+
+impl DebugWireframes {
+    pub fn new() -> Self {
+        Self { vertices: Vec::new(), enabled: true }
+    }
+
+    pub fn clear(&mut self) {
+        self.vertices.clear();
+    }
+
+    /// add a single line segment
+    pub fn add_line(&mut self, start: [f32; 3], end: [f32; 3], color: [f32; 4]) {
+        self.vertices.push(DebugWireframeVertex { position: start, color });
+        self.vertices.push(DebugWireframeVertex { position: end, color });
+    }
+
+    /// add a wireframe box from min/max corners
+    pub fn add_box(&mut self, min: [f32; 3], max: [f32; 3], color: [f32; 4]) {
+        let [x0, y0, z0] = min;
+        let [x1, y1, z1] = max;
+
+        // bottom face edges
+        self.add_line([x0, y0, z0], [x1, y0, z0], color);
+        self.add_line([x1, y0, z0], [x1, y0, z1], color);
+        self.add_line([x1, y0, z1], [x0, y0, z1], color);
+        self.add_line([x0, y0, z1], [x0, y0, z0], color);
+
+        // top face edges
+        self.add_line([x0, y1, z0], [x1, y1, z0], color);
+        self.add_line([x1, y1, z0], [x1, y1, z1], color);
+        self.add_line([x1, y1, z1], [x0, y1, z1], color);
+        self.add_line([x0, y1, z1], [x0, y1, z0], color);
+
+        // vertical edges
+        self.add_line([x0, y0, z0], [x0, y1, z0], color);
+        self.add_line([x1, y0, z0], [x1, y1, z0], color);
+        self.add_line([x1, y0, z1], [x1, y1, z1], color);
+        self.add_line([x0, y0, z1], [x0, y1, z1], color);
+    }
+}
+
+pub type DebugWireframesRef = Rc<RefCell<DebugWireframes>>;
+
+#[derive(Clone)]
+pub struct PlatformContext {
+    pub current_event: Event<()>,
+    pub asset_manager: ModelManagerRef,
+    pub frame_width: f32,
+    pub frame_height: f32,
+    pub time_ctx: TimeContext,
+    pub window: Arc<Mutex<winit::window::Window>>,
+    pub egui_queue: Rc<RefCell<EguiQueue>>,
+    pub settings: Arc<RwLock<Settings>>,
+    /// shared debug wireframe buffer
+    pub debug_wireframes: DebugWireframesRef,
+    /// sets whether or not egui will receive input events
+    pub should_egui_receive_input_events: Rc<Cell<bool>>,
+}
+
+#[derive(Clone)]
+pub struct TimeContext {
+    pub frame_dt: f32,
+    pub fixed_dt: f32,
+    pub alpha: f32,
+}

platform/src/lib.rs

@@ -1,6 +1,9 @@
 pub mod platform;
 mod camera;
+mod event;
+pub mod context;
+pub mod settings;
 
 pub use platform::Platform;
 pub use camera::Camera;
-pub use raidillon_core::context::PlatformContext;
+pub use context::{PlatformContext, TimeContext, DebugWireframes, DebugWireframesRef, DebugWireframeVertex};

platform/src/platform.rs

@@ -1,8 +1,7 @@
-use raidillon_assets::ModelManager;
-use raidillon_core::engine::EngineTrait;
 use crate::PlatformContext;
+use raidillon_core::engine::EngineTrait;
 
-pub trait Platform<E: EngineTrait> {
+pub trait Platform<E: EngineTrait<PlatformCtx = PlatformContext>> {
     /// Initialize platform.
     fn initialize(engine: E, title: String, width: u32, height: u32) -> Self;
     fn run(self);

platform/src/settings.rs

@@ -0,0 +1,166 @@
+use winit::monitor::{MonitorHandle, VideoModeHandle};
+use winit::window::{Fullscreen, Window};
+use serde::{Serialize, Deserialize};
+use std::error::Error;
+use std::fs;
+use std::io;
+use std::path::{Path, PathBuf};
+
+pub fn default_config_path() -> PathBuf {
+    let exe_path = std::env::current_exe().unwrap();
+    let exe_dir = exe_path
+        .parent()
+        .ok_or_else(|| std::io::Error::new(std::io::ErrorKind::Other, "executable has no parent")).unwrap();
+
+    exe_dir.join("settings.toml")
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize, Default)]
+#[serde(rename_all = "snake_case")]
+pub enum WindowMode {
+    BorderlessFullscreen,
+    ExclusiveFullscreen,
+    #[default]
+    Windowed,
+}
+
+#[derive(Debug, Default, Serialize, Deserialize)]
+pub struct Settings {
+    pub display_settings: DisplaySettings,
+}
+
+impl Settings {
+    pub fn load_from_file(path: impl AsRef<Path>) -> Result<Self, Box<dyn Error>> {
+        let path = path.as_ref();
+        let text = fs::read_to_string(path)?;
+        let settings: Settings = toml::from_str(&text)?;
+        Ok(settings)
+    }
+
+    pub fn save_to_file(&self, path: impl AsRef<Path>) -> Result<(), Box<dyn Error>> {
+        let path = path.as_ref();
+        if let Some(parent) = path.parent() {
+            fs::create_dir_all(parent)?;
+        }
+        let toml_str = toml::to_string_pretty(self)?;
+        fs::write(path, toml_str)?;
+        Ok(())
+    }
+
+    pub fn load_or_default(path: impl AsRef<Path>) -> Result<Self, Box<dyn Error>> {
+        let path = path.as_ref();
+
+        match fs::read_to_string(path) {
+            Ok(text) => {
+                let settings: Settings = toml::from_str(&text)?;
+                Ok(settings)
+            }
+            Err(err) if err.kind() == io::ErrorKind::NotFound => {
+                let settings = Settings::default();
+                if let Some(parent) = path.parent() {
+                    fs::create_dir_all(parent)?;
+                }
+                let toml_str = toml::to_string_pretty(&settings)?;
+                fs::write(path, toml_str)?;
+                Ok(settings)
+            }
+            Err(err) => Err(Box::new(err)),
+        }
+    }
+}
+
+#[derive(Debug, Serialize, Deserialize)]
+#[serde(default)]
+pub struct DisplaySettings {
+    pub fullscreen_mode: WindowMode,
+    #[serde(skip)]
+    pub dirty: bool,
+}
+
+impl Default for DisplaySettings {
+    fn default() -> Self {
+        Self {
+            fullscreen_mode: WindowMode::Windowed,
+            dirty: false,
+        }
+    }
+}
+
+impl DisplaySettings {
+    pub fn apply(&self, window: &Window) {
+        // apply fullscreen mode
+        match self.fullscreen_mode {
+            WindowMode::BorderlessFullscreen => {
+                let monitor = window.current_monitor().or_else(|| window.primary_monitor());
+                window.set_fullscreen(Some(Fullscreen::Borderless(monitor)));
+            }
+            WindowMode::ExclusiveFullscreen => {
+                let monitor = window.current_monitor().or_else(|| window.primary_monitor());
+                match monitor {
+                    Some(monitor) => {
+                        if let Some(video_mode) = pick_best_video_mode(&monitor) {
+                            window.set_fullscreen(Some(Fullscreen::Exclusive(video_mode)));
+                        } else {
+                            // fallback to borderless
+                            window.set_fullscreen(Some(Fullscreen::Borderless(Some(monitor))));
+                        }
+                    }
+                    None => {
+                        // no monitor info, fallback to windowed
+                        window.set_fullscreen(None);
+                    }
+                }
+            }
+            WindowMode::Windowed => {
+                window.set_fullscreen(None);
+            },
+        }
+    }
+}
+
+fn pick_best_video_mode(monitor: &MonitorHandle) -> Option<VideoModeHandle> {
+    let target_size = monitor.size();
+
+    let mut best_native: Option<VideoModeHandle> = None;
+    let mut best_any: Option<VideoModeHandle> = None;
+
+    for mode in monitor.video_modes() {
+        if mode.size() == target_size {
+            let replace = match best_native.as_ref() {
+                None => true,
+                Some(best) => {
+                    (mode.refresh_rate_millihertz(), mode.bit_depth())
+                        > (best.refresh_rate_millihertz(), best.bit_depth())
+                }
+            };
+            if replace {
+                best_native = Some(mode.clone());
+            }
+        }
+
+        let replace = match best_any.as_ref() {
+            None => true,
+            Some(best) => is_better_video_mode(&mode, best),
+        };
+        if replace {
+            best_any = Some(mode);
+        }
+    }
+
+    best_native.or(best_any)
+}
+
+fn is_better_video_mode(a: &VideoModeHandle, b: &VideoModeHandle) -> bool {
+    let a_size = a.size();
+    let b_size = b.size();
+    let a_area = u64::from(a_size.width) * u64::from(a_size.height);
+    let b_area = u64::from(b_size.width) * u64::from(b_size.height);
+
+    match a_area.cmp(&b_area) {
+        std::cmp::Ordering::Greater => true,
+        std::cmp::Ordering::Less => false,
+        std::cmp::Ordering::Equal => {
+            (a.refresh_rate_millihertz(), a.bit_depth()) > (b.refresh_rate_millihertz(), b.bit_depth())
+        }
+    }
+}