feat(platform): Centralize platform-specific WebGPU code and improve shader composition

5 files changed, 24 insertions, 125 deletions

diff --git a/src/gpu/effect.cc b/src/gpu/effect.cc
index a1b45f1..9e769eb 100644
--- a/src/gpu/effect.cc
+++ b/src/gpu/effect.cc
@@ -260,9 +260,7 @@ void MainSequence::render_frame(float global_time, float beat, float peak,
   scene_attachment.loadOp = WGPULoadOp_Clear;
   scene_attachment.storeOp = WGPUStoreOp_Store;
   scene_attachment.clearValue = {0, 0, 0, 1};
-#if !defined(DEMO_CROSS_COMPILE_WIN32)
   scene_attachment.depthSlice = WGPU_DEPTH_SLICE_UNDEFINED;
-#endif /* !defined(DEMO_CROSS_COMPILE_WIN32) */
 
   WGPURenderPassDepthStencilAttachment depth_attachment = {};
   depth_attachment.view = depth_view_;
@@ -302,9 +300,7 @@ void MainSequence::render_frame(float global_time, float beat, float peak,
     final_attachment.resolveTarget = nullptr;
     final_attachment.loadOp = WGPULoadOp_Load;
     final_attachment.storeOp = WGPUStoreOp_Store;
-#if !defined(DEMO_CROSS_COMPILE_WIN32)
     final_attachment.depthSlice = WGPU_DEPTH_SLICE_UNDEFINED;
-#endif /* !defined(DEMO_CROSS_COMPILE_WIN32) */
     WGPURenderPassDescriptor final_desc = {
         .colorAttachmentCount = 1, .colorAttachments = &final_attachment};
     WGPURenderPassEncoder final_pass =
@@ -338,9 +334,7 @@ void MainSequence::render_frame(float global_time, float beat, float peak,
       pp_attachment.resolveTarget = nullptr;
       pp_attachment.loadOp = WGPULoadOp_Load;
       pp_attachment.storeOp = WGPUStoreOp_Store;
-#if !defined(DEMO_CROSS_COMPILE_WIN32)
       pp_attachment.depthSlice = WGPU_DEPTH_SLICE_UNDEFINED;
-#endif /* !defined(DEMO_CROSS_COMPILE_WIN32) */
       WGPURenderPassDescriptor pp_desc = {.colorAttachmentCount = 1,
                                           .colorAttachments = &pp_attachment};
       WGPURenderPassEncoder pp_pass =
diff --git a/src/gpu/effects/shader_composer.cc b/src/gpu/effects/shader_composer.cc
index b746f8b..5cd8699 100644
--- a/src/gpu/effects/shader_composer.cc
+++ b/src/gpu/effects/shader_composer.cc
@@ -2,6 +2,7 @@
 // It implements the ShaderComposer class.
 
 #include "gpu/effects/shader_composer.h"
+#include "util/asset_manager.h"
 #include <set>
 #include <sstream>
 
@@ -86,3 +87,12 @@ ShaderComposer::Compose(const std::vector<std::string>& dependencies,
 
   return ss.str();
 }
+
+std::string
+ShaderComposer::Compose(const std::vector<std::string>& dependencies,
+                        AssetId main_code_asset_id,
+                        const CompositionMap& substitutions) {
+  size_t size;
+  const char* main_code = reinterpret_cast<const char*>(GetAsset(main_code_asset_id, &size));
+  return Compose(dependencies, std::string(main_code, size), substitutions);
+}
diff --git a/src/gpu/effects/shader_composer.h b/src/gpu/effects/shader_composer.h
index 9eb43f4..961ffcb 100644
--- a/src/gpu/effects/shader_composer.h
+++ b/src/gpu/effects/shader_composer.h
@@ -3,6 +3,7 @@
 
 #pragma once
 
+#include "generated/assets.h" // For AssetId
 #include <map>
 #include <set>
 #include <string>
@@ -23,6 +24,10 @@ class ShaderComposer {
   std::string Compose(const std::vector<std::string>& dependencies,
                       const std::string& main_code,
                       const CompositionMap& substitutions = {});
+  
+  std::string Compose(const std::vector<std::string>& dependencies,
+                      AssetId main_code_asset_id,
+                      const CompositionMap& substitutions = {});
 
  private:
   ShaderComposer() = default;
diff --git a/src/gpu/gpu.cc b/src/gpu/gpu.cc
index 9776eac..c61c605 100644
--- a/src/gpu/gpu.cc
+++ b/src/gpu/gpu.cc
@@ -57,11 +57,7 @@ RenderPass gpu_create_render_pass(WGPUDevice device, WGPUTextureFormat format,
   RenderPass pass = {};
 
   // Create Shader Module
-  WGPUShaderSourceWGSL wgsl_src = {};
-  wgsl_src.chain.sType = WGPUSType_ShaderSourceWGSL;
-  wgsl_src.code = str_view(shader_code);
-  WGPUShaderModuleDescriptor shader_desc = {};
-  shader_desc.nextInChain = &wgsl_src.chain;
+  WGPUShaderModuleDescriptor shader_desc = platform_create_shader_module_descriptor(shader_code);
   WGPUShaderModule shader_module =
       wgpuDeviceCreateShaderModule(device, &shader_desc);
 
@@ -145,7 +141,7 @@ RenderPass gpu_create_render_pass(WGPUDevice device, WGPUTextureFormat format,
   depth_stencil.format = WGPUTextureFormat_Depth24Plus;
   depth_stencil.depthWriteEnabled = WGPUOptionalBool_False;
   depth_stencil.depthCompare = WGPUCompareFunction_Always;
-  pipeline_desc.depthStencil = &depth_stencil;
+  PLATFORM_SET_PIPELINE_DEPTH_STENCIL(pipeline_desc, &depth_stencil);
 
   pass.pipeline = wgpuDeviceCreateRenderPipeline(device, &pipeline_desc);
 
@@ -157,11 +153,7 @@ ComputePass gpu_create_compute_pass(WGPUDevice device, const char* shader_code,
                                     int num_bindings) {
   ComputePass pass = {};
 
-  WGPUShaderSourceWGSL wgsl_src = {};
-  wgsl_src.chain.sType = WGPUSType_ShaderSourceWGSL;
-  wgsl_src.code = str_view(shader_code);
-  WGPUShaderModuleDescriptor shader_desc = {};
-  shader_desc.nextInChain = &wgsl_src.chain;
+  WGPUShaderModuleDescriptor shader_desc = platform_create_shader_module_descriptor(shader_code);
   WGPUShaderModule shader_module =
       wgpuDeviceCreateShaderModule(device, &shader_desc);
 
@@ -214,49 +206,11 @@ ComputePass gpu_create_compute_pass(WGPUDevice device, const char* shader_code,
 
 #if !defined(STRIP_ALL)
 #if defined(DEMO_CROSS_COMPILE_WIN32)
-static void handle_request_adapter(WGPURequestAdapterStatus status,
-                                   WGPUAdapter adapter, const char* message,
-                                   void* userdata) {
-  if (status == WGPURequestAdapterStatus_Success) {
-    *((WGPUAdapter*)userdata) = adapter;
-  } else {
-    printf("Request adapter failed: %s\n", message ? message : "Unknown");
-  }
-}
-static void handle_request_device(WGPURequestDeviceStatus status,
-                                  WGPUDevice device, const char* message,
-                                  void* userdata) {
-  if (status == WGPURequestDeviceStatus_Success) {
-    *((WGPUDevice*)userdata) = device;
-  } else {
-    printf("Request device failed: %s\n", message ? message : "Unknown");
-  }
-}
 static void handle_device_error(WGPUErrorType type, const char* message,
                                 void* userdata) {
   printf("WebGPU Error: %s\n", message ? message : "Unknown");
 }
 #else
-static void handle_request_adapter(WGPURequestAdapterStatus status,
-                                   WGPUAdapter adapter, WGPUStringView message,
-                                   void* userdata, void* userdata2) {
-  (void)userdata2;
-  if (status == WGPURequestAdapterStatus_Success) {
-    *((WGPUAdapter*)userdata) = adapter;
-  } else {
-    printf("Request adapter failed: %.*s\n", (int)message.length, message.data);
-  }
-}
-static void handle_request_device(WGPURequestDeviceStatus status,
-                                  WGPUDevice device, WGPUStringView message,
-                                  void* userdata, void* userdata2) {
-  (void)userdata2;
-  if (status == WGPURequestDeviceStatus_Success) {
-    *((WGPUDevice*)userdata) = device;
-  } else {
-    printf("Request device failed: %.*s\n", (int)message.length, message.data);
-  }
-}
 static void handle_device_error(const WGPUDevice* device, WGPUErrorType type,
                                 WGPUStringView message, void* userdata,
                                 void* userdata2) {
@@ -266,41 +220,6 @@ static void handle_device_error(const WGPUDevice* device, WGPUErrorType type,
   printf("WebGPU Error: %.*s\n", (int)message.length, message.data);
 }
 #endif /* defined(DEMO_CROSS_COMPILE_WIN32) */
-#else
-// STRIP_ALL versions
-#if defined(DEMO_CROSS_COMPILE_WIN32)
-static void handle_request_adapter(WGPURequestAdapterStatus status,
-                                   WGPUAdapter adapter, const char* message,
-                                   void* userdata) {
-  if (status == WGPURequestAdapterStatus_Success) {
-    *((WGPUAdapter*)userdata) = adapter;
-  }
-}
-static void handle_request_device(WGPURequestDeviceStatus status,
-                                  WGPUDevice device, const char* message,
-                                  void* userdata) {
-  if (status == WGPURequestDeviceStatus_Success) {
-    *((WGPUDevice*)userdata) = device;
-  }
-}
-#else
-static void handle_request_adapter(WGPURequestAdapterStatus status,
-                                   WGPUAdapter adapter, WGPUStringView message,
-                                   void* userdata, void* userdata2) {
-  (void)userdata2;
-  if (status == WGPURequestAdapterStatus_Success) {
-    *((WGPUAdapter*)userdata) = adapter;
-  }
-}
-static void handle_request_device(WGPURequestDeviceStatus status,
-                                  WGPUDevice device, WGPUStringView message,
-                                  void* userdata, void* userdata2) {
-  (void)userdata2;
-  if (status == WGPURequestDeviceStatus_Success) {
-    *((WGPUDevice*)userdata) = device;
-  }
-}
-#endif /* defined(DEMO_CROSS_COMPILE_WIN32) */
 #endif /* !defined(STRIP_ALL) */
 
 void gpu_init(PlatformState* platform_state) {
@@ -311,16 +230,8 @@ void gpu_init(PlatformState* platform_state) {
   adapter_opts.compatibleSurface = g_surface;
   adapter_opts.powerPreference = WGPUPowerPreference_HighPerformance;
 
-#if defined(DEMO_CROSS_COMPILE_WIN32)
-  wgpuInstanceRequestAdapter(g_instance, &adapter_opts, handle_request_adapter,
-                             &g_adapter);
-#else
-  WGPURequestAdapterCallbackInfo adapter_cb = {};
-  adapter_cb.mode = WGPUCallbackMode_WaitAnyOnly;
-  adapter_cb.callback = handle_request_adapter;
-  adapter_cb.userdata1 = &g_adapter;
-  wgpuInstanceRequestAdapter(g_instance, &adapter_opts, adapter_cb);
-#endif /* defined(DEMO_CROSS_COMPILE_WIN32) */
+  platform_wgpu_request_adapter(g_instance, &adapter_opts, &g_adapter);
+
   while (!g_adapter)
     platform_wgpu_wait_any(g_instance);
 
@@ -331,16 +242,8 @@ void gpu_init(PlatformState* platform_state) {
 #endif /* !defined(DEMO_CROSS_COMPILE_WIN32) */
 #endif /* !defined(STRIP_ALL) */
 
-#if defined(DEMO_CROSS_COMPILE_WIN32)
-  wgpuAdapterRequestDevice(g_adapter, &device_desc, handle_request_device,
-                           &g_device);
-#else
-  WGPURequestDeviceCallbackInfo device_cb = {};
-  device_cb.mode = WGPUCallbackMode_WaitAnyOnly;
-  device_cb.callback = handle_request_device;
-  device_cb.userdata1 = &g_device;
-  wgpuAdapterRequestDevice(g_adapter, &device_desc, device_cb);
-#endif /* defined(DEMO_CROSS_COMPILE_WIN32) */
+  platform_wgpu_request_device(g_adapter, &device_desc, &g_device);
+
   while (!g_device)
     platform_wgpu_wait_any(g_instance);
 
diff --git a/src/gpu/texture_manager.cc b/src/gpu/texture_manager.cc
index 0c30c94..e69425f 100644
--- a/src/gpu/texture_manager.cc
+++ b/src/gpu/texture_manager.cc
@@ -2,19 +2,10 @@
 // It implements the TextureManager.
 
 #include "gpu/texture_manager.h"
+#include "platform/platform.h" // Include for WGPU_TEX_COPY_INFO and WGPU_TEX_DATA_LAYOUT
 #include <cstdio>
 #include <vector>
 
-#if defined(DEMO_CROSS_COMPILE_WIN32)
-// Old API
-#define WGPU_TEX_COPY_INFO WGPUImageCopyTexture
-#define WGPU_TEX_DATA_LAYOUT WGPUTextureDataLayout
-#else
-// New API
-#define WGPU_TEX_COPY_INFO WGPUTexelCopyTextureInfo
-#define WGPU_TEX_DATA_LAYOUT WGPUTexelCopyBufferLayout
-#endif
-
 void TextureManager::init(WGPUDevice device, WGPUQueue queue) {
   device_ = device;
   queue_ = queue;
@@ -60,11 +51,7 @@ void TextureManager::create_texture(const std::string& name, int width,
   tex_desc.format = WGPUTextureFormat_RGBA8Unorm;
   tex_desc.mipLevelCount = 1;
   tex_desc.sampleCount = 1;
-#if defined(DEMO_CROSS_COMPILE_WIN32)
-  tex_desc.label = nullptr;
-#else
-  tex_desc.label = {nullptr, 0};
-#endif
+  tex_desc.label = label_view(name.c_str());
 
   WGPUTexture texture = wgpuDeviceCreateTexture(device_, &tex_desc);