implement ImageFromAsset for Metal

pthom · Dec 30, 2023 · b6f53c7 · b6f53c7
1 parent c31bffc
commit b6f53c7
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Showing 7 changed files with 155 additions and 7 deletions.
diff --git a/src/hello_imgui/internal/backend_impls/rendering_metal.h b/src/hello_imgui/internal/backend_impls/rendering_metal.h
@@ -27,6 +27,7 @@ namespace HelloImGui
         id<MTLCommandQueue> mtlCommandQueue = nullptr;
         MTLRenderPassDescriptor* mtlRenderPassDescriptor = nullptr;
         id <MTLRenderCommandEncoder> mtlRenderCommandEncoder = nullptr;
+        id<MTLDevice> mtlDevice = nullptr;
     };
     MetalGlobals& GetMetalGlobals();
 
@@ -56,7 +57,6 @@ namespace HelloImGui
     struct GlfwMetalGlobals
     {
         GLFWwindow* glfwWindow = nullptr;
-        id<MTLDevice> mtlDevice = nullptr;
     };
     GlfwMetalGlobals& GetGlfwMetalGlobals();
 #endif

diff --git a/src/hello_imgui/internal/backend_impls/rendering_metal_glfw.mm b/src/hello_imgui/internal/backend_impls/rendering_metal_glfw.mm
@@ -33,16 +33,16 @@ void PrepareGlfwForMetal(GLFWwindow* glfwWindow)
         auto& gGlfwMetalGlobals = GetGlfwMetalGlobals();
         {
             gGlfwMetalGlobals.glfwWindow = glfwWindow;
-            gGlfwMetalGlobals.mtlDevice = MTLCreateSystemDefaultDevice();
-            gMetalGlobals.mtlCommandQueue = [gGlfwMetalGlobals.mtlDevice newCommandQueue];
+            gMetalGlobals.mtlDevice = MTLCreateSystemDefaultDevice();
+            gMetalGlobals.mtlCommandQueue = [gMetalGlobals.mtlDevice newCommandQueue];
         }
         {
             ImGui_ImplGlfw_InitForOther(gGlfwMetalGlobals.glfwWindow, true);
-            ImGui_ImplMetal_Init(gGlfwMetalGlobals.mtlDevice);
+            ImGui_ImplMetal_Init(gMetalGlobals.mtlDevice);
 
             NSWindow* nswin = glfwGetCocoaWindow(gGlfwMetalGlobals.glfwWindow);
             gMetalGlobals.caMetalLayer = [CAMetalLayer layer];
-            gMetalGlobals.caMetalLayer.device = gGlfwMetalGlobals.mtlDevice;
+            gMetalGlobals.caMetalLayer.device = gMetalGlobals.mtlDevice;
             gMetalGlobals.caMetalLayer.pixelFormat = MTLPixelFormatBGRA8Unorm;
             nswin.contentView.layer = gMetalGlobals.caMetalLayer;
             nswin.contentView.wantsLayer = YES;

diff --git a/src/hello_imgui/internal/backend_impls/rendering_metal_sdl.mm b/src/hello_imgui/internal/backend_impls/rendering_metal_sdl.mm
@@ -30,6 +30,7 @@ void PrepareSdlForMetal(SDL_Window* sdlWindow)
 
         {
             gSdlMetalGlobals.sdlWindow = sdlWindow;
+            gMetalGlobals.mtlDevice = MTLCreateSystemDefaultDevice();
             gSdlMetalGlobals.sdlRenderer = SDL_CreateRenderer(sdlWindow, -1, SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC);
             if (gSdlMetalGlobals.sdlRenderer == nullptr)
             {

diff --git a/src/hello_imgui/internal/image_from_asset_metal.cpp b/src/hello_imgui/internal/image_from_asset_metal.cpp
@@ -0,0 +1,85 @@
+#ifdef HELLOIMGUI_HAS_METAL
+#include "hello_imgui/image_from_asset.h"
+#include "imgui.h"
+#include "hello_imgui/internal/image_metal.h"
+#include "hello_imgui/internal/stb_image.h"
+#include "hello_imgui/hello_imgui_assets.h"
+
+#include <string>
+#include <unordered_map>
+
+namespace HelloImGui
+{
+    static std::unordered_map<std::string, ImageMetalPtr> gImageFromAssetMap;
+
+
+    static ImageMetalPtr _GetCachedImageMetal(const char*assetPath)
+    {
+        if (gImageFromAssetMap.find(assetPath) != gImageFromAssetMap.end())
+            return gImageFromAssetMap.at(assetPath);
+
+        // Load the image using stbi_load_from_memory
+        auto assetData = LoadAssetFileData(assetPath);
+        assert(assetData.data != nullptr);
+        int width, height;
+        unsigned char*image_data_rgba = stbi_load_from_memory(
+            (unsigned char *)assetData.data, (int)assetData.dataSize,
+            &width, &height, NULL, 4);
+        if (image_data_rgba == NULL)
+        {
+            IM_ASSERT(false && "ImageMetal: Failed to load image!");
+            return nullptr;
+        }
+
+        // Create and store the VkImage
+        if (gImageFromAssetMap.find(assetPath) == gImageFromAssetMap.end())
+            gImageFromAssetMap[assetPath] = std::make_shared<ImageMetal>(width, height, image_data_rgba);
+
+        // Release image memory using stb
+        stbi_image_free(image_data_rgba);
+
+        return gImageFromAssetMap.at(assetPath);
+    }
+
+    void ImageFromAsset(
+        const char *assetPath, const ImVec2& size,
+        const ImVec2& uv0, const ImVec2& uv1,
+        const ImVec4& tint_col, const ImVec4& border_col)
+    {
+        auto textureId = ImTextureIdFromAsset(assetPath);
+        auto imageSize = ImageSizeFromAsset(assetPath);
+        ImVec2 displayedSize = ImageProportionalSize(size, imageSize);
+        ImGui::Image(textureId, displayedSize, uv0, uv1, tint_col, border_col);
+    }
+
+    bool ImageButtonFromAsset(const char *assetPath, const ImVec2& size, const ImVec2& uv0,  const ImVec2& uv1, int frame_padding, const ImVec4& bg_col, const ImVec4& tint_col)
+    {
+        auto textureId = ImTextureIdFromAsset(assetPath);
+        auto imageSize = ImageSizeFromAsset(assetPath);
+        ImVec2 displayedSize = ImageProportionalSize(size, imageSize);
+        bool clicked = ImGui::ImageButton(textureId, displayedSize, uv0, uv1, frame_padding, bg_col, tint_col);
+        return clicked;
+    }
+
+    ImTextureID ImTextureIdFromAsset(const char *assetPath)
+    {
+        auto cachedImage = _GetCachedImageMetal(assetPath);
+        return (ImTextureID) cachedImage->Texture;
+    }
+
+    ImVec2 ImageSizeFromAsset(const char *assetPath)
+    {
+        auto cachedImage = _GetCachedImageMetal(assetPath);
+        return ImVec2((float)cachedImage->Width, (float)cachedImage->Height);
+    }
+
+    namespace internal
+    {
+        void Free_ImageFromAssetMap()
+        {
+            gImageFromAssetMap.clear();
+        }
+    }
+
+} // namespace HelloImGui
+#endif // #ifdef HELLOIMGUI_HAS_METAL
diff --git a/src/hello_imgui/internal/image_from_asset_none.cpp b/src/hello_imgui/internal/image_from_asset_none.cpp
@@ -1,7 +1,7 @@
 #include "image_from_asset.h"
 
 
-#if !defined(HELLOIMGUI_HAS_VULKAN) && !defined(HELLOIMGUI_HAS_OPENGL)
+#if !defined(HELLOIMGUI_HAS_VULKAN) && !defined(HELLOIMGUI_HAS_OPENGL) && !defined(HELLOIMGUI_HAS_METAL)
 
 #include "imgui.h"
 
@@ -38,4 +38,5 @@ namespace HelloImGui
         void Free_ImageFromAssetMap() {}
     }
 } // namespace HelloImGui
-#endif // #if !defined(HELLOIMGUI_HAS_VULKAN) && !defined(HELLOIMGUI_HAS_OPENGL)
+
+#endif
diff --git a/src/hello_imgui/internal/image_metal.h b/src/hello_imgui/internal/image_metal.h
@@ -0,0 +1,23 @@
+#pragma once
+#ifdef HELLOIMGUI_HAS_METAL
+
+#include <Metal/Metal.h>
+#include <QuartzCore/CAMetalLayer.h>
+#include <memory>
+
+namespace HelloImGui
+{
+    struct ImageMetal
+    {
+        ImageMetal(int width, int height, unsigned char* image_data_rgba);
+        ~ImageMetal();
+
+        id<MTLTexture> Texture;
+        int Width;
+        int Height;
+    };
+
+    using ImageMetalPtr = std::shared_ptr<ImageMetal>;
+}
+
+#endif // #ifdef HELLOIMGUI_HAS_METAL
diff --git a/src/hello_imgui/internal/image_metal.mm b/src/hello_imgui/internal/image_metal.mm
@@ -0,0 +1,38 @@
+#ifdef HELLOIMGUI_HAS_METAL
+#include "image_metal.h"
+
+#include "imgui.h"
+#include "hello_imgui/internal/backend_impls/rendering_metal.h"
+
+namespace HelloImGui
+{
+
+    ImageMetal::ImageMetal(int width, int height, unsigned char* image_data_rgba)
+        : Width(width), Height(height)
+    {
+        auto gMetalGlobals = GetMetalGlobals();
+
+        // Create a MTLTextureDescriptor
+        MTLTextureDescriptor* textureDescriptor = [[MTLTextureDescriptor alloc] init];
+        textureDescriptor.pixelFormat = MTLPixelFormatRGBA8Unorm; // Adjust as needed
+        textureDescriptor.width = width;
+        textureDescriptor.height = height;
+        textureDescriptor.usage = MTLTextureUsageShaderRead | MTLTextureUsageRenderTarget;
+
+        // Create the texture from the descriptor
+        Texture = [gMetalGlobals.mtlDevice newTextureWithDescriptor:textureDescriptor];
+
+        // Upload the image data to the texture
+        MTLRegion region = MTLRegionMake2D(0, 0, width, height);
+        [Texture replaceRegion:region mipmapLevel:0 withBytes:image_data_rgba bytesPerRow:4 * width];
+
+        [textureDescriptor release];
+    }
+
+    ImageMetal::~ImageMetal()
+    {
+        [Texture release];
+    }
+}
+
+#endif // #ifdef HELLOIMGUI_HAS_VULKAN