add texture to frag shader. fix weird macro name collision bug

ROADMAP.md

@@ -11,6 +11,7 @@ Here is the current list of planned features. All items are sorted in approximat
     * Skeletal animation
     * Macro to produce vertex buffer attributes (and maybe descriptors) from structs
     * Add runtime type safety to uniform bindings (and maybe compile time)
+    * Inject layout set/bindings into shader source so they don't need to be defined in-shader
 * Error Handling
     * Custom error type?
     * Remove as many panics / unwraps as possible

bevy_derive/src/lib.rs

@@ -166,7 +166,7 @@ pub fn derive_uniforms(input: TokenStream) -> TokenStream {
 
                 Some(potential_shader_defs.drain(..)
                     .filter(|(f, shader_def)| shader_def.is_some())
-                    .map(|(f, shader_def)| format!("{}{}", f, shader_def.unwrap()))
+                    .map(|(f, shader_def)| format!("{}_{}{}", #struct_name_screaming_snake, f, shader_def.unwrap()))
                     .collect::<Vec<String>>())
             }
         }

docs/debugging.md

@@ -0,0 +1,6 @@
+# Debugging
+
+## Macro Debugging
+
+* Print the final output of a macro using ```cargo rustc --profile=check -- -Zunstable-options --pretty=expanded```
+* Print output during macro compilation using ```eprintln!("hi");```

examples/custom_shader.rs

@@ -60,7 +60,7 @@ fn main() {
                                 void main() {
                                     o_Target = color;
 
-                                # ifdef always_red
+                                # ifdef MY_MATERIAL_always_red
                                     o_Target = vec4(0.8, 0.0, 0.0, 1.0);
                                 # endif
                                 }

examples/texture.rs

@@ -10,7 +10,7 @@ fn setup(world: &mut World) {
         mesh_storage.add(Mesh::load(MeshType::Cube))
     };
 
-    let _texture_handle = {
+    let texture_handle = {
         let mut texture_storage = world.resources.get_mut::<AssetStorage<Texture>>().unwrap();
         let texture = Texture::load(TextureType::Data(asset::create_texels(256)));
         texture_storage.add(texture)
@@ -22,7 +22,7 @@ fn setup(world: &mut World) {
         .add_archetype(MeshEntity {
             mesh: cube_handle.clone(),
             material: StandardMaterial {
-                albedo: math::vec4(0.5, 0.3, 0.3, 1.0).into(),
+                albedo: texture_handle.into(),
             },
             translation: Translation::new(0.0, 0.0, 1.0),
             ..Default::default()

src/render/color.rs

@@ -15,6 +15,12 @@ impl From<Vec4> for ColorSource {
     }
 }
 
+impl From<Handle<Texture>> for ColorSource {
+    fn from(texture: Handle<Texture>) -> Self {
+        ColorSource::Texture(texture)
+    }
+}
+
 impl ShaderDefSuffixProvider for ColorSource {
     fn get_shader_def(&self) -> Option<&'static str> {
         match *self {

src/render/render_graph/pipelines/forward/forward.frag

@@ -23,12 +23,21 @@ layout(set = 0, binding = 1) uniform Lights {
     Light SceneLights[MAX_LIGHTS];
 };
 
+# ifdef STANDARD_MATERIAL_albedo_texture
+layout(set = 1, binding = 1) uniform texture2D StandardMaterial_albedo_texture;
+layout(set = 1, binding = 2) uniform sampler StandardMaterial_albedo_sampler;
+# else
 layout(set = 1, binding = 1) uniform StandardMaterial_albedo {
     vec4 Albedo;
 };
-
+# endif
 
 void main() {
+# ifdef STANDARD_MATERIAL_albedo_texture
+    vec4 Albedo = texture(
+        sampler2D(StandardMaterial_albedo_texture, StandardMaterial_albedo_sampler),
+        v_Uv);
+# endif
     vec3 normal = normalize(v_Normal);
     vec3 ambient = vec3(0.05, 0.05, 0.05);
     // accumulate color