Remove some downstream hacks from wgpu backend

Author: hazeycode

build.zig

@@ -241,7 +241,11 @@ pub fn build(b: *std.Build) void {
                     "libs/imgui/backends/imgui_impl_glfw.cpp",
                     "libs/imgui/backends/imgui_impl_wgpu.cpp",
                 },
-                .flags = &(cflags.* ++ .{"-DGLFW_INCLUDE_NONE"}),
+                .flags = &(cflags.* ++ .{
+                    "-DGLFW_INCLUDE_NONE",
+                    // TODO: This should be IMGUI_IMPL_WEBGPU_BACKEND_DAWN but we're using an old version of Dawn that looks more like wgpu_native
+                    "-DIMGUI_IMPL_WEBGPU_BACKEND_WGPU",
+                }),
             });
         },
         .glfw_opengl3 => {

libs/imgui/backends/imgui_impl_wgpu.cpp

@@ -45,9 +45,6 @@
 // When targeting native platforms (i.e. NOT emscripten), one of IMGUI_IMPL_WEBGPU_BACKEND_DAWN
 // or IMGUI_IMPL_WEBGPU_BACKEND_WGPU must be provided. See imgui_impl_wgpu.h for more details.
 
-// FIX(zig-gamedev)
-#define IMGUI_IMPL_WEBGPU_BACKEND_WGPU
-
 #ifndef __EMSCRIPTEN__
     #if defined(IMGUI_IMPL_WEBGPU_BACKEND_DAWN) == defined(IMGUI_IMPL_WEBGPU_BACKEND_WGPU)
     #error exactly one of IMGUI_IMPL_WEBGPU_BACKEND_DAWN or IMGUI_IMPL_WEBGPU_BACKEND_WGPU must be defined!
@@ -61,8 +58,7 @@
 #include "imgui.h"
 #ifndef IMGUI_DISABLE
 
-// FIX(zig-gamedev):
-// #include "imgui_impl_wgpu.h"
+#include "imgui_impl_wgpu.h"
 
 #include <limits.h>
 #include <webgpu/webgpu.h>
@@ -71,47 +67,6 @@
 extern ImGuiID ImHashData(const void* data_p, size_t data_size, ImU32 seed = 0);
 #define MEMALIGN(_SIZE,_ALIGN)        (((_SIZE) + ((_ALIGN) - 1)) & ~((_ALIGN) - 1))    // Memory align (copied from IM_ALIGN() macro).
 
-// FIX(zig-gamedev): We removed header file and declare all our external functions here.
-extern "C" {
-
-// Initialization data, for ImGui_ImplWGPU_Init()
-struct ImGui_ImplWGPU_InitInfo
-{
-    WGPUDevice              Device;
-    int                     NumFramesInFlight = 3;
-    WGPUTextureFormat       RenderTargetFormat = WGPUTextureFormat_Undefined;
-    WGPUTextureFormat       DepthStencilFormat = WGPUTextureFormat_Undefined;
-    WGPUMultisampleState    PipelineMultisampleState = {};
-
-    ImGui_ImplWGPU_InitInfo()
-    {
-        PipelineMultisampleState.count = 1;
-        PipelineMultisampleState.mask = UINT32_MAX;
-        PipelineMultisampleState.alphaToCoverageEnabled = false;
-    }
-};
-
-// Follow "Getting Started" link and check examples/ folder to learn about using backends!
-IMGUI_IMPL_API bool ImGui_ImplWGPU_Init(ImGui_ImplWGPU_InitInfo* init_info);
-IMGUI_IMPL_API void ImGui_ImplWGPU_Shutdown();
-IMGUI_IMPL_API void ImGui_ImplWGPU_NewFrame();
-IMGUI_IMPL_API void ImGui_ImplWGPU_RenderDrawData(ImDrawData* draw_data, WGPURenderPassEncoder pass_encoder);
-
-// Use if you want to reset your rendering device without losing Dear ImGui state.
-IMGUI_IMPL_API bool ImGui_ImplWGPU_CreateDeviceObjects();
-IMGUI_IMPL_API void ImGui_ImplWGPU_InvalidateDeviceObjects();
-
-// [BETA] Selected render state data shared with callbacks.
-// This is temporarily stored in GetPlatformIO().Renderer_RenderState during the ImGui_ImplWGPU_RenderDrawData() call.
-// (Please open an issue if you feel you need access to more data)
-struct ImGui_ImplWGPU_RenderState
-{
-    WGPUDevice                  Device;
-    WGPURenderPassEncoder       RenderPassEncoder;
-};
-
-} // extern "C"
-
 // WebGPU data
 struct RenderResources
 {

libs/imgui/backends/imgui_impl_wgpu.h

@@ -8,9 +8,6 @@
 // This requirement will be removed once WebGPU stabilizes and backends converge on a unified interface.
 //#define IMGUI_IMPL_WEBGPU_BACKEND_DAWN
 
-// FIX(zig-gamedev)
-#define IMGUI_IMPL_WEBGPU_BACKEND_WGPU
-
 // Implemented features:
 //  [X] Renderer: User texture binding. Use 'WGPUTextureView' as ImTextureID. Read the FAQ about ImTextureID!
 //  [X] Renderer: Large meshes support (64k+ vertices) even with 16-bit indices (ImGuiBackendFlags_RendererHasVtxOffset).
@@ -32,6 +29,9 @@
 
 #include <webgpu/webgpu.h>
 
+// FIX(zig-gamedev)
+extern "C" {
+
 // Initialization data, for ImGui_ImplWGPU_Init()
 struct ImGui_ImplWGPU_InitInfo
 {
@@ -68,4 +68,6 @@ struct ImGui_ImplWGPU_RenderState
     WGPURenderPassEncoder       RenderPassEncoder;
 };
 
+}
+
 #endif // #ifndef IMGUI_DISABLE