do not depend on spirv on wasm target (#689)

do not use spirv for wasm target

CHANGELOG.md

@@ -3,19 +3,19 @@
 ## Unreleased
 
 ### Added
-
+- [Do not depend on spirv on wasm32 target][689]
 - [Another fast compile flag for macOS][552]
 
 ### Changed
 
 - Breaking Change: [sRGB awareness for `Color`][616]
-  - Color is now assumed to be provided in the non-linear sRGB colorspace, and constructors such as `Color::rgb` and `Color::rgba` will be converted to linear sRGB under-the-hood. 
+  - Color is now assumed to be provided in the non-linear sRGB colorspace, and constructors such as `Color::rgb` and `Color::rgba` will be converted to linear sRGB under-the-hood.
   - This allows drop-in use of colors from most applications.
   - New methods `Color::rgb_linear` and `Color::rgba_linear` will accept colors already in linear sRGB (the old behavior)
   - Individual color-components must now be accessed through setters and getters: `.r`, `.g`, `.b`, `.a`, `.set_r`, `.set_g`, `.set_b`, `.set_a`, and the corresponding methods with the `*_linear` suffix.
 - Despawning an entity multiple times causes a debug-level log message to be emitted instead of a panic [649] [651]
 
-
+[689]: https://github.com/bevyengine/bevy/pull/689
 [552]: https://github.com/bevyengine/bevy/pull/552
 [616]: https://github.com/bevyengine/bevy/pull/616
 [649]: https://github.com/bevyengine/bevy/pull/649
@@ -43,7 +43,7 @@
   - e.g. `query.iter().par_iter(batch_size).for_each(/* ... */)`
 - [Added gamepad support using Gilrs][280]
 - [Implement WASM support for bevy_winit][503]
-- [Create winit canvas under WebAssembly][506] 
+- [Create winit canvas under WebAssembly][506]
 - [Implement single threaded task scheduler for WebAssembly][496]
 - [Support for binary glTF (.glb).][271]
 - [Support for `Or` in ECS queries.][358]
@@ -72,7 +72,7 @@
 - [Add `AppBuilder::add_startup_stage_|before/after`][505]
 
 ### Changed
- 
+
 - [Transform rewrite][374]
 - [Use generational entity ids and other optimizations][504]
 - [Optimize transform systems to only run on changes.][417]

crates/bevy_render/Cargo.toml

@@ -27,7 +27,6 @@ bevy_window = { path = "../bevy_window", version = "0.2.1" }
 bevy_utils = { path = "../bevy_utils", version = "0.2.1" }
 
 # rendering
-spirv-reflect = "0.2.3"
 image = { version = "0.23", default-features = false }
 
 # misc
@@ -45,7 +44,10 @@ hex = "0.4.2"
 hexasphere = "1.0.0"
 parking_lot = "0.11.0"
 
-[target.'cfg(not(target_os = "ios"))'.dependencies]
+[target.'cfg(not(target_arch = "wasm32"))'.dependencies]
+spirv-reflect = "0.2.3"
+
+[target.'cfg(all(not(target_os = "ios"), not(target_arch = "wasm32")))'.dependencies]
 bevy-glsl-to-spirv = "0.1.7"
 
 [target.'cfg(target_os = "ios")'.dependencies]

crates/bevy_render/src/shader/mod.rs

@@ -1,8 +1,26 @@
 #[allow(clippy::module_inception)]
 mod shader;
 mod shader_defs;
+
+#[cfg(not(target_arch = "wasm32"))]
+mod shader_reflect;
+
+#[cfg(target_arch = "wasm32")]
+#[path = "shader_reflect_wasm.rs"]
 mod shader_reflect;
 
 pub use shader::*;
 pub use shader_defs::*;
 pub use shader_reflect::*;
+
+use crate::pipeline::{BindGroupDescriptor, VertexBufferDescriptor};
+
+/// Defines the memory layout of a shader
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct ShaderLayout {
+    pub bind_groups: Vec<BindGroupDescriptor>,
+    pub vertex_buffer_descriptors: Vec<VertexBufferDescriptor>,
+    pub entry_point: String,
+}
+
+pub const GL_VERTEX_INDEX: &str = "gl_VertexIndex";

crates/bevy_render/src/shader/shader.rs

@@ -10,7 +10,7 @@ pub enum ShaderStage {
     Compute,
 }
 
-#[cfg(not(target_os = "ios"))]
+#[cfg(all(not(target_os = "ios"), not(target_arch = "wasm32")))]
 impl Into<bevy_glsl_to_spirv::ShaderType> for ShaderStage {
     fn into(self) -> bevy_glsl_to_spirv::ShaderType {
         match self {
@@ -21,7 +21,7 @@ impl Into<bevy_glsl_to_spirv::ShaderType> for ShaderStage {
     }
 }
 
-#[cfg(not(target_os = "ios"))]
+#[cfg(all(not(target_os = "ios"), not(target_arch = "wasm32")))]
 fn glsl_to_spirv(
     glsl_source: &str,
     stage: ShaderStage,
@@ -116,6 +116,7 @@ impl Shader {
         }
     }
 
+    #[cfg(not(target_arch = "wasm32"))]
     pub fn get_spirv(&self, macros: Option<&[String]>) -> Vec<u32> {
         match self.source {
             ShaderSource::Spirv(ref bytes) => bytes.clone(),
@@ -123,9 +124,13 @@ impl Shader {
         }
     }
 
+    #[allow(unused_variables)]
     pub fn get_spirv_shader(&self, macros: Option<&[String]>) -> Shader {
         Shader {
+            #[cfg(not(target_arch = "wasm32"))]
             source: ShaderSource::Spirv(self.get_spirv(macros)),
+            #[cfg(target_arch = "wasm32")]
+            source: self.source.clone(),
             stage: self.stage,
         }
     }
@@ -143,12 +148,31 @@ impl Shader {
 }
 
 /// All stages in a shader program
-#[derive(Clone, Debug)]
+#[derive(Clone, Debug, Eq, PartialEq, Hash)]
 pub struct ShaderStages {
     pub vertex: Handle<Shader>,
     pub fragment: Option<Handle<Shader>>,
 }
 
+pub struct ShaderStagesIterator<'a> {
+    shader_stages: &'a ShaderStages,
+    state: u32,
+}
+
+impl<'a> Iterator for ShaderStagesIterator<'a> {
+    type Item = Handle<Shader>;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        let ret = match self.state {
+            0 => Some(self.shader_stages.vertex),
+            1 => self.shader_stages.fragment,
+            _ => None,
+        };
+        self.state += 1;
+        ret
+    }
+}
+
 impl ShaderStages {
     pub fn new(vertex_shader: Handle<Shader>) -> Self {
         ShaderStages {
@@ -156,4 +180,11 @@ impl ShaderStages {
             fragment: None,
         }
     }
+
+    pub fn iter(&self) -> ShaderStagesIterator {
+        ShaderStagesIterator {
+            shader_stages: &self,
+            state: 0,
+        }
+    }
 }

crates/bevy_render/src/shader/shader_reflect.rs

@@ -3,6 +3,7 @@ use crate::{
         BindGroupDescriptor, BindType, BindingDescriptor, BindingShaderStage, InputStepMode,
         UniformProperty, VertexAttributeDescriptor, VertexBufferDescriptor, VertexFormat,
     },
+    shader::{ShaderLayout, GL_VERTEX_INDEX},
     texture::{TextureComponentType, TextureViewDimension},
 };
 use bevy_core::AsBytes;
@@ -16,16 +17,6 @@ use spirv_reflect::{
     ShaderModule,
 };
 
-/// Defines the memory layout of a shader
-#[derive(Debug, Clone, PartialEq, Eq)]
-pub struct ShaderLayout {
-    pub bind_groups: Vec<BindGroupDescriptor>,
-    pub vertex_buffer_descriptors: Vec<VertexBufferDescriptor>,
-    pub entry_point: String,
-}
-
-pub const GL_VERTEX_INDEX: &str = "gl_VertexIndex";
-
 impl ShaderLayout {
     pub fn from_spirv(spirv_data: &[u32], bevy_conventions: bool) -> ShaderLayout {
         match ShaderModule::load_u8_data(spirv_data.as_bytes()) {

crates/bevy_render/src/shader/shader_reflect_wasm.rs

@@ -0,0 +1,7 @@
+use crate::shader::ShaderLayout;
+
+impl ShaderLayout {
+    pub fn from_spirv(_spirv_data: &[u32], _bevy_conventions: bool) -> ShaderLayout {
+        panic!("reflecting shader layout from spirv data is not available");
+    }
+}