feat: Compile to WGSL

crates/flare-lib/Cargo.toml

@@ -15,6 +15,7 @@ wgpu.workspace = true
 
 [build-dependencies]
 spirv-builder.workspace = true
+wgpu.workspace = true
 
 [lints]
 workspace = true

crates/flare-lib/build.rs

@@ -1,23 +1,36 @@
-use spirv_builder::{Capability, MetadataPrintout, SpirvBuilder};
+use spirv_builder::{MetadataPrintout, SpirvBuilder};
 use std::env;
 use std::fs;
+use std::fs::File;
+use std::io::{BufReader, Read, Write};
 use std::path::{Path, PathBuf};
+use wgpu::naga;
+use wgpu::naga::back::wgsl::WriterFlags;
+use wgpu::naga::front::spv::Options;
+use wgpu::naga::valid::{Capabilities, ValidationFlags};
 
 fn main() -> Result<(), Box<dyn std::error::Error>> {
     let gpu_crate_path = Path::new("../flare-shader/");
 
     // Compile the shader crate with SpirvBuilder.
-    let result = SpirvBuilder::new(gpu_crate_path, "spirv-unknown-vulkan1.2")
-        .capability(Capability::Int64)
+    let result = SpirvBuilder::new(gpu_crate_path, "spirv-unknown-spv1.3")
         .print_metadata(MetadataPrintout::Full)
         .build()?;
 
     // Copy the SPIR-V to this crate's output directory
     let shader_path = result.module.unwrap_single();
     let output_path = PathBuf::from(env::var("OUT_DIR")?).join("shader_binary.spv");
-
     fs::copy(shader_path, &output_path)?;
 
+    // Re-compile as wgsl
+    let mut spv_binary = vec![];
+    BufReader::new(File::open(&output_path)?).read_to_end(&mut spv_binary)?;
+    let module = naga::front::spv::parse_u8_slice(&spv_binary, &Options::default())?;
+    let module_info = naga::valid::Validator::new(ValidationFlags::default(), Capabilities::default()).validate(&module)?;
+    let wgsl_string = naga::back::wgsl::write_string(&module, &module_info, WriterFlags::empty())?;
+
+    File::create(PathBuf::from(env::var("OUT_DIR")?).join("shader.wgsl"))?.write_all(wgsl_string.as_bytes())?;
+
     println!("Generated shader binary constant at {:?}", output_path);
     Ok(())
 }