Add 'glsl' feature to gate naga glsl features (#59)

This can be used to reduce the final binary size when a consumer only
needs WGSL support. I've enabled the feature by default for
backwards-compatibility

---------

Co-authored-by: robtfm <[email protected]>

.github/workflows/rust.yml

@@ -10,7 +10,9 @@ jobs:
       - uses: actions/checkout@v2
       - uses: dtolnay/rust-toolchain@stable
       - name: Check
-        run: cargo check
+        run: |
+          cargo check
+          cargo check --no-default-features
 
   check-wasm:
     name: Check (Wasm)
@@ -21,7 +23,9 @@ jobs:
         with:
           target: wasm32-unknown-unknown
       - name: Check wasm
-        run: cargo check --target wasm32-unknown-unknown
+        run: |
+          cargo check --target wasm32-unknown-unknown
+          cargo check --target wasm32-unknown-unknown --no-default-features
 
   test-windows:
     name: Test Suite (Windows)

Cargo.toml

@@ -8,15 +8,16 @@ repository = "https://github.com/bevyengine/naga_oil/"
 readme = "README.md"
 
 [features]
-default = ["test_shader"]
+default = ["test_shader", "glsl"]
 # enable tests that need a graphical card
 test_shader = []
-prune = []
+glsl = ["naga/glsl-in", "naga/glsl-out"]
 override_any = []
+prune = []
 allow_deprecated = []
 
 [dependencies]
-naga = { version = "0.13", features = ["wgsl-in", "wgsl-out", "glsl-in", "glsl-out", "clone", "span"] }
+naga = { version = "0.13", features = ["wgsl-in", "wgsl-out", "clone", "span"] }
 tracing = "0.1"
 regex = "1.8"
 regex-syntax = "0.7"

src/compose/error.rs

@@ -76,10 +76,12 @@ pub enum ComposerErrorInner {
     ImportNotFound(String, usize),
     #[error("{0}")]
     WgslParseError(naga::front::wgsl::ParseError),
+    #[cfg(feature = "glsl")]
     #[error("{0:?}")]
     GlslParseError(Vec<naga::front::glsl::Error>),
     #[error("naga_oil bug, please file a report: failed to convert imported module IR back into WGSL for use with WGSL shaders: {0}")]
     WgslBackError(naga::back::wgsl::Error),
+    #[cfg(feature = "glsl")]
     #[error("naga_oil bug, please file a report: failed to convert imported module IR back into GLSL for use with GLSL shaders: {0}")]
     GlslBackError(naga::back::glsl::Error),
     #[error("naga_oil bug, please file a report: composer failed to build a valid header: {0}")]
@@ -222,6 +224,7 @@ impl ComposerError {
                     .collect(),
                 vec![e.message().to_owned()],
             ),
+            #[cfg(feature = "glsl")]
             ComposerErrorInner::GlslParseError(e) => (
                 e.iter()
                     .map(|naga::front::glsl::Error { kind, meta }| {
@@ -246,6 +249,7 @@ impl ComposerError {
             ComposerErrorInner::WgslBackError(e) => {
                 return format!("{path}: wgsl back error: {e}");
             }
+            #[cfg(feature = "glsl")]
             ComposerErrorInner::GlslBackError(e) => {
                 return format!("{path}: glsl back error: {e}");
             }

src/compose/mod.rs

@@ -151,21 +151,25 @@ pub mod util;
 pub enum ShaderLanguage {
     #[default]
     Wgsl,
+    #[cfg(feature = "glsl")]
     Glsl,
 }
 
 #[derive(Hash, PartialEq, Eq, Clone, Copy, Debug, Default)]
 pub enum ShaderType {
     #[default]
     Wgsl,
+    #[cfg(feature = "glsl")]
     GlslVertex,
+    #[cfg(feature = "glsl")]
     GlslFragment,
 }
 
 impl From<ShaderType> for ShaderLanguage {
     fn from(ty: ShaderType) -> Self {
         match ty {
             ShaderType::Wgsl => ShaderLanguage::Wgsl,
+            #[cfg(feature = "glsl")]
             ShaderType::GlslVertex | ShaderType::GlslFragment => ShaderLanguage::Glsl,
         }
     }
@@ -468,7 +472,7 @@ impl Composer {
         &self,
         naga_module: &mut naga::Module,
         language: ShaderLanguage,
-        header_for: &str,
+        #[allow(unused)] header_for: &str, // Only used when GLSL is enabled
     ) -> Result<String, ComposerErrorInner> {
         // TODO: cache headers again
         let info =
@@ -483,6 +487,7 @@ impl Composer {
                 naga::back::wgsl::WriterFlags::EXPLICIT_TYPES,
             )
             .map_err(ComposerErrorInner::WgslBackError),
+            #[cfg(feature = "glsl")]
             ShaderLanguage::Glsl => {
                 let vec4 = naga_module.types.insert(
                     naga::Type {
@@ -574,6 +579,7 @@ impl Composer {
 
         let mut module_string = match language {
             ShaderLanguage::Wgsl => String::new(),
+            #[cfg(feature = "glsl")]
             ShaderLanguage::Glsl => String::from("#version 450\n"),
         };
 
@@ -657,6 +663,7 @@ impl Composer {
                     },
                 }
             })?,
+            #[cfg(feature = "glsl")]
             ShaderLanguage::Glsl => naga::front::glsl::Frontend::default()
                 .parse(
                     &naga::front::glsl::Options {
@@ -694,12 +701,14 @@ impl Composer {
         owned_types: &HashSet<String>,
     ) -> Result<(), ComposerErrorInner> {
         // TODO: remove this once glsl front support is complete
+        #[cfg(feature = "glsl")]
         if lang == ShaderLanguage::Glsl {
             return Ok(());
         }
 
         let recompiled = match lang {
             ShaderLanguage::Wgsl => naga::front::wgsl::parse_str(header).unwrap(),
+            #[cfg(feature = "glsl")]
             ShaderLanguage::Glsl => naga::front::glsl::Frontend::default()
                 .parse(
                     &naga::front::glsl::Options {
@@ -1137,7 +1146,12 @@ impl Composer {
 
         if self.validate && create_headers {
             // check that identifiers haven't been renamed
-            for language in [ShaderLanguage::Wgsl, ShaderLanguage::Glsl] {
+            #[allow(clippy::single_element_loop)]
+            for language in [
+                ShaderLanguage::Wgsl,
+                #[cfg(feature = "glsl")]
+                ShaderLanguage::Glsl,
+            ] {
                 let header = self
                     .naga_to_string(&mut header_ir, language, &module_definition.name)
                     .map_err(wrap_err)?;
@@ -1673,7 +1687,9 @@ impl Composer {
         Self::add_composable_data(&mut derived, &composable, None, 0, false);
 
         let stage = match shader_type {
+            #[cfg(feature = "glsl")]
             ShaderType::GlslVertex => Some(naga::ShaderStage::Vertex),
+            #[cfg(feature = "glsl")]
             ShaderType::GlslFragment => Some(naga::ShaderStage::Fragment),
             _ => None,
         };

src/compose/test.rs

@@ -303,6 +303,7 @@ mod test {
         output_eq!(text, "tests/expected/missing_import.txt");
     }
 
+    #[cfg(feature = "glsl")]
     #[test]
     fn wgsl_call_glsl() {
         let mut composer = Composer::default();
@@ -354,6 +355,7 @@ mod test {
         let _ = wgsl;
     }
 
+    #[cfg(feature = "glsl")]
     #[test]
     fn glsl_call_wgsl() {
         let mut composer = Composer::default();
@@ -394,6 +396,7 @@ mod test {
         output_eq!(wgsl, "tests/expected/glsl_call_wgsl.txt");
     }
 
+    #[cfg(feature = "glsl")]
     #[test]
     fn basic_glsl() {
         let mut composer = Composer::default();
@@ -693,6 +696,7 @@ mod test {
         output_eq!(wgsl, "tests/expected/import_in_decl.txt");
     }
 
+    #[cfg(feature = "glsl")]
     #[test]
     fn glsl_const_import() {
         let mut composer = Composer::default();
@@ -734,6 +738,7 @@ mod test {
         output_eq!(wgsl, "tests/expected/glsl_const_import.txt");
     }
 
+    #[cfg(feature = "glsl")]
     #[test]
     fn glsl_wgsl_const_import() {
         let mut composer = Composer::default();
@@ -773,6 +778,7 @@ mod test {
 
         output_eq!(wgsl, "tests/expected/glsl_wgsl_const_import.txt");
     }
+    #[cfg(feature = "glsl")]
     #[test]
     fn wgsl_glsl_const_import() {
         let mut composer = Composer::default();