collect uniform shader_defs in preparation for on-demand shader compiling

src/app/app_builder.rs

@@ -8,7 +8,7 @@ use crate::{
         passes::*,
         render_graph_2::{
             passes::*, pipelines::*, renderers::wgpu_renderer::WgpuRenderer, resource_providers::*,
-            StandardMaterial,
+            ShaderAssignments, StandardMaterial,
         },
         *,
     },
@@ -164,6 +164,8 @@ impl AppBuilder {
         resources.insert(Time::new());
         resources.insert(AssetStorage::<Mesh>::new());
         resources.insert(AssetStorage::<Texture>::new());
+        resources.insert(AssetStorage::<Shader>::new());
+        resources.insert(ShaderAssignments::new());
         self
     }
 

src/asset/mod.rs

@@ -8,6 +8,7 @@ pub use texture::*;
 
 use std::{collections::HashMap, marker::PhantomData};
 
+#[derive(Hash)]
 pub struct Handle<T> {
     pub id: usize,
     marker: PhantomData<T>,

src/render/render_graph_2/renderable.rs

@@ -1,10 +1,11 @@
-use crate::{asset::Handle, render::Shader};
-use legion::prelude::Entity;
-use std::collections::HashSet;
+use crate::{asset::{AssetStorage, Handle}, render::Shader, render::render_graph_2::RenderGraph};
+use legion::prelude::*;
+use std::collections::{HashMap, HashSet};
 
 pub struct Renderable {
     pub is_visible: bool,
     pub shaders: Vec<Handle<Shader>>,
+    pub shader_defs: HashSet<String>,
 }
 
 impl Default for Renderable {
@@ -12,10 +13,38 @@ impl Default for Renderable {
         Renderable {
             is_visible: true,
             shaders: Vec::new(),
+            shader_defs: HashSet::new(),
         }
     }
 }
 
 pub struct ShaderAssignments {
-    pub assignments: HashSet<usize, Vec<Entity>>,
+    pub assignments: HashMap<usize, Vec<Entity>>,
 }
+
+impl ShaderAssignments {
+    pub fn new() -> Self {
+        ShaderAssignments {
+            assignments: HashMap::new(),
+        }
+    }
+}
+
+pub fn update_shader_assignments(world: &mut World, render_graph: &mut RenderGraph) {
+    // PERF: this seems like a lot of work for things that don't change that often.
+    // lots of string + hashset allocations. sees uniform_resource_provider for more context
+    {
+        let shader_assignments = world.resources.get_mut::<ShaderAssignments>().unwrap();
+        let shader_storage = world.resources.get_mut::<AssetStorage<Shader>>().unwrap();
+        for (entity, renderable) in <Read<Renderable>>::query().iter_entities(world) {
+            for shader in renderable.shaders.iter() {
+                
+            }
+        }
+    }
+
+    // cleanup entity shader_defs so next frame they can be refreshed
+    for mut renderable in <Write<Renderable>>::query().iter_mut(world) {
+        renderable.shader_defs = HashSet::new();
+    }
+}

src/render/render_graph_2/renderers/wgpu_renderer.rs

@@ -1,10 +1,10 @@
 use crate::{
     legion::prelude::*,
     render::render_graph_2::{
-        resource_name, BindGroup, BindType, DynamicUniformBufferInfo, PassDescriptor,
-        PipelineDescriptor, RenderGraph, RenderPass, RenderPassColorAttachmentDescriptor,
-        RenderPassDepthStencilAttachmentDescriptor, Renderer, ResourceInfo, ShaderUniforms,
-        TextureDescriptor,
+        resource_name, update_shader_assignments, BindGroup, BindType, DynamicUniformBufferInfo,
+        PassDescriptor, PipelineDescriptor, RenderGraph, RenderPass,
+        RenderPassColorAttachmentDescriptor, RenderPassDepthStencilAttachmentDescriptor, Renderer,
+        ResourceInfo, ShaderUniforms, TextureDescriptor,
     },
 };
 use std::{collections::HashMap, ops::Deref};
@@ -470,6 +470,8 @@ impl Renderer for WgpuRenderer {
             resource_provider.update(self, world);
         }
 
+        update_shader_assignments(world, render_graph);
+
         for (name, texture_descriptor) in render_graph.queued_textures.drain(..) {
             self.create_texture(&name, &texture_descriptor);
         }

src/render/render_graph_2/resource_providers/uniform_resource_provider.rs

@@ -136,7 +136,7 @@ where
                     for (uniforms, _renderable) in query.iter(world) {
                         // TODO: check if index has changed. if it has, then entity should be updated
                         // TODO: only mem-map entities if their data has changed
-                        // TODO: try getting ref first
+                        // TODO: try getting bytes ref first
                         if let Some(uniform_bytes) = uniforms.get_uniform_bytes(name) {
                             mapped[offset..(offset + uniform_bytes.len())]
                                 .copy_from_slice(uniform_bytes.as_slice());
@@ -148,6 +148,15 @@ where
 
             renderer.copy_buffer_to_buffer("tmp_uniform_mapped", 0, name, 0, size);
         }
+
+        // update shader assignments based on current macro defs
+        for (uniforms, mut renderable) in <(Read<T>, Write<Renderable>)>::query().iter_mut(world) {
+            if let Some(shader_defs) = uniforms.get_shader_defs() {
+                for shader_def in shader_defs {
+                    renderable.shader_defs.insert(shader_def);
+                }
+            }
+        }
     }
 
     fn resize(