Use IndexMap in glium rendering systems

- Improve RenderingContext
- Improve RenderingSystem trait

raidillon_glium/src/system.rs

@@ -1,39 +1,38 @@
-use std::collections::HashMap;
-use std::sync::{Arc, RwLock};
 use raidillon_core::Scene;
-use glium::Surface;
+use glium::Frame;
 use crate::GliumAssetManager;
+use indexmap::IndexMap;
 
-pub struct RenderingContext<'a, S: Surface> {
-    pub scene: &'a mut Scene,
-    pub target: &'a mut S,
-    pub asset_manager: Arc<RwLock<GliumAssetManager>>,
+pub struct RenderingContext<'a> {
+    pub scene: &'a Scene,
+    pub target: &'a mut Frame,
+    pub asset_manager: &'a mut GliumAssetManager,
 }
 
 /// The internal "rendering system" trait of raidillon_glium.
 /// This is unrelated to the main System trait in raidillon_core.
 pub trait RenderingSystem {
-    fn render<S: Surface>(ctx: &mut RenderingContext<S>);
-    fn compile_shaders() {}
+    fn render(&mut self, ctx: &mut RenderingContext);
+    fn compile_shaders(&mut self) {}
 }
 
 type SystemID = String;
 
-pub struct RenderingSystemManager<T: RenderingSystem> {
-    pub systems: HashMap<SystemID, Box<T>>,
+pub struct RenderingSystemManager {
+    pub systems: IndexMap<SystemID, Box<dyn RenderingSystem>>,
 }
 
-impl<T: RenderingSystem> RenderingSystemManager<T> {
+impl RenderingSystemManager {
     pub fn new() -> Self {
         Self {
-            systems: HashMap::new(),
+            systems: IndexMap::default(),
         }
     }
-    pub fn add_system(&mut self, id: SystemID, system: T) {
-        self.systems.insert(id, Box::new(system));
+    pub fn add_system(&mut self, id: SystemID, system: Box<dyn RenderingSystem>) {
+        self.systems.insert(id, system);
     }
 
     pub fn remove_system(&mut self, id: SystemID) {
-        self.systems.remove(&id);
+        self.systems.shift_remove(&id);
     }
 }