1 files changed, 95 insertions, 0 deletions
diff --git a/third_party/rust/glsl/src/transpiler/spirv.rs b/third_party/rust/glsl/src/transpiler/spirv.rs
new file mode 100644
index 0000000000..a75f3afab6
--- /dev/null
+++ b/third_party/rust/glsl/src/transpiler/spirv.rs
@@ -0,0 +1,95 @@
+//! SPIR-V transpiler.
+//!
+//! The current implementation uses the [shaderc](https://crates.io/crates/shaderc) crate to
+//! transpile GLSL to SPIR-V. This is not ideal but will provide a default and starting
+//! implementation.
+
+use shaderc;
+
+use crate::syntax;
+use crate::transpiler::glsl as glsl_transpiler;
+
+#[derive(Clone, Copy, Debug, Eq, Hash, PartialEq)]
+pub enum ShaderKind {
+  TessControl,
+  TessEvaluation,
+  Vertex,
+  Geometry,
+  Fragment,
+  Compute,
+}
+
+impl From<ShaderKind> for shaderc::ShaderKind {
+  fn from(kind: ShaderKind) -> Self {
+    match kind {
+      ShaderKind::TessControl => shaderc::ShaderKind::TessControl,
+      ShaderKind::TessEvaluation => shaderc::ShaderKind::TessEvaluation,
+      ShaderKind::Vertex => shaderc::ShaderKind::Vertex,
+      ShaderKind::Geometry => shaderc::ShaderKind::Geometry,
+      ShaderKind::Fragment => shaderc::ShaderKind::Fragment,
+      ShaderKind::Compute => shaderc::ShaderKind::Compute,
+    }
+  }
+}
+
+/// Transpile a GLSL AST into a SPIR-V internal buffer and write it to the given buffer.
+///
+/// The current implementation is highly inefficient as it relies on internal allocations and
+/// [shaderc](https://crates.io/crates/shaderc).
+///
+/// If any error happens while transpiling, they’re returned as an opaque string.
+pub fn transpile_translation_unit_to_binary<F>(
+  f: &mut F,
+  tu: &syntax::TranslationUnit,
+  kind: ShaderKind,
+) -> Result<(), String>
+where
+  F: std::io::Write,
+{
+  // write as GLSL in an intermediate buffer
+  let mut glsl_buffer = String::new();
+  glsl_transpiler::show_translation_unit(&mut glsl_buffer, tu);
+
+  // pass the GLSL-formatted string to shaderc
+  let mut compiler = shaderc::Compiler::new().unwrap();
+  let options = shaderc::CompileOptions::new().unwrap();
+  let kind = kind.into();
+  let output = compiler
+    .compile_into_spirv(&glsl_buffer, kind, "glsl input", "main", Some(&options))
+    .map_err(|e| format!("{}", e))?;
+
+  let _ = f.write_all(output.as_binary_u8());
+
+  Ok(())
+}
+
+/// Transpile a GLSL AST into a SPIR-V internal buffer and write it to the given buffer.
+///
+/// The current implementation is highly inefficient as it relies on internal allocations and
+/// [shaderc](https://crates.io/crates/shaderc).
+///
+/// If any error happens while transpiling, they’re returned as an opaque string.
+pub fn transpile_translation_unit<F>(
+  f: &mut F,
+  tu: &syntax::TranslationUnit,
+  kind: ShaderKind,
+) -> Result<(), String>
+where
+  F: std::fmt::Write,
+{
+  // write as GLSL in an intermediate buffer
+  let mut glsl_buffer = String::new();
+  glsl_transpiler::show_translation_unit(&mut glsl_buffer, tu);
+
+  // pass the GLSL-formatted string to shaderc
+  let mut compiler = shaderc::Compiler::new().unwrap();
+  let options = shaderc::CompileOptions::new().unwrap();
+  let kind = kind.into();
+  let output = compiler
+    .compile_into_spirv_assembly(&glsl_buffer, kind, "glsl input", "main", Some(&options))
+    .map_err(|e| format!("{}", e))?;
+
+  let _ = f.write_str(&output.as_text());
+
+  Ok(())
+}