From 22f87aa7f8561ca62dc108071deb5365744cf434 Mon Sep 17 00:00:00 2001
From: chyyran <ronny@ronnychan.ca>
Date: Mon, 5 Dec 2022 23:09:59 -0500
Subject: [PATCH] reflect: add `FromCompilation<GlslangCompilation>` for SpirV

---
 librashader-reflect/src/back/mod.rs     |  1 +
 librashader-reflect/src/back/spirv.rs   | 56 +++++++++++++++++++++++++
 librashader-reflect/src/back/targets.rs |  4 +-
 librashader/src/lib.rs                  |  2 +-
 4 files changed, 60 insertions(+), 3 deletions(-)
 create mode 100644 librashader-reflect/src/back/spirv.rs

diff --git a/librashader-reflect/src/back/mod.rs b/librashader-reflect/src/back/mod.rs
index 6784118..3faeb13 100644
--- a/librashader-reflect/src/back/mod.rs
+++ b/librashader-reflect/src/back/mod.rs
@@ -1,5 +1,6 @@
 pub mod cross;
 pub mod targets;
+mod spirv;
 
 use crate::back::targets::OutputTarget;
 use crate::error::{ShaderCompileError, ShaderReflectError};
diff --git a/librashader-reflect/src/back/spirv.rs b/librashader-reflect/src/back/spirv.rs
new file mode 100644
index 0000000..4b7ace8
--- /dev/null
+++ b/librashader-reflect/src/back/spirv.rs
@@ -0,0 +1,56 @@
+use crate::back::{CompilerBackend, CompileShader, FromCompilation, ShaderCompilerOutput};
+use crate::back::targets::SpirV;
+use crate::error::{ShaderCompileError, ShaderReflectError};
+use crate::front::shaderc::GlslangCompilation;
+use crate::reflect::{ReflectShader, ShaderReflection};
+use crate::reflect::cross::{GlslReflect};
+use crate::reflect::semantics::ShaderSemantics;
+
+struct WriteSpirV {
+    // rely on GLSL to provide out reflection but we don't actually need the AST.
+    reflect: GlslReflect,
+    vertex: Vec<u32>,
+    fragment: Vec<u32>
+}
+
+impl FromCompilation<GlslangCompilation> for SpirV {
+    type Target = SpirV;
+    type Options = Option<()>;
+    type Context = ();
+    type Output = impl CompileShader<Self::Target, Options = Option<()>, Context = ()>
+    + ReflectShader;
+
+    fn from_compilation(
+        compile: GlslangCompilation,
+    ) -> Result<CompilerBackend<Self::Output>, ShaderReflectError> {
+        let vertex = compile.vertex.as_binary().to_vec();
+        let fragment = compile.vertex.as_binary().to_vec();
+        let reflect = GlslReflect::try_from(compile)?;
+        Ok(CompilerBackend {
+            backend: WriteSpirV {
+                reflect,
+                vertex,
+                fragment,
+            },
+        })
+    }
+}
+
+impl ReflectShader for WriteSpirV {
+    fn reflect(&mut self, pass_number: usize, semantics: &ShaderSemantics) -> Result<ShaderReflection, ShaderReflectError> {
+        self.reflect.reflect(pass_number, semantics)
+    }
+}
+
+impl CompileShader<SpirV> for WriteSpirV {
+    type Options = Option<()>;
+    type Context = ();
+
+    fn compile(self, _options: Self::Options) -> Result<ShaderCompilerOutput<Vec<u32>, Self::Context>, ShaderCompileError> {
+        Ok(ShaderCompilerOutput {
+            vertex: self.vertex,
+            fragment: self.fragment,
+            context: (),
+        })
+    }
+}
\ No newline at end of file
diff --git a/librashader-reflect/src/back/targets.rs b/librashader-reflect/src/back/targets.rs
index d1e5955..8999bf9 100644
--- a/librashader-reflect/src/back/targets.rs
+++ b/librashader-reflect/src/back/targets.rs
@@ -9,7 +9,7 @@ pub struct GLSL;
 /// Shader compiler target for HLSL.
 pub struct HLSL;
 /// Shader compiler target for SPIR-V.
-pub struct SPIRV;
+pub struct SpirV;
 /// Shader compiler target for MSL
 pub struct MSL;
 
@@ -19,7 +19,7 @@ impl OutputTarget for GLSL {
 impl OutputTarget for HLSL {
     type Output = String;
 }
-impl OutputTarget for SPIRV {
+impl OutputTarget for SpirV {
     type Output = Vec<u32>;
 }
 
diff --git a/librashader/src/lib.rs b/librashader/src/lib.rs
index 2fe4c4e..86e7cf6 100644
--- a/librashader/src/lib.rs
+++ b/librashader/src/lib.rs
@@ -68,7 +68,7 @@ pub mod reflect {
     pub mod targets {
         pub use librashader_reflect::back::targets::GLSL;
         pub use librashader_reflect::back::targets::HLSL;
-        pub use librashader_reflect::back::targets::SPIRV;
+        pub use librashader_reflect::back::targets::SpirV;
     }
 
     pub use librashader_reflect::error::*;