Added hardware ImGui renderer.

CMakeLists.txt

@@ -169,6 +169,8 @@ set(SOURCE_FILES
         SpaceCadetPinball/imgui_demo.cpp
         SpaceCadetPinball/imgui_impl_sdl.cpp
         SpaceCadetPinball/imgui_impl_sdl.h
+        SpaceCadetPinball/imgui_impl_sdlrenderer.h
+        SpaceCadetPinball/imgui_impl_sdlrenderer.cpp
         SpaceCadetPinball/imstb_textedit.h
         SpaceCadetPinball/imstb_rectpack.h
         SpaceCadetPinball/imstb_truetype.h
@@ -193,6 +195,7 @@ set_source_files_properties(
         SpaceCadetPinball/imgui_tables.cpp
         SpaceCadetPinball/imgui_demo.cpp
         SpaceCadetPinball/imgui_impl_sdl.cpp
+        SpaceCadetPinball/imgui_impl_sdlrenderer.cpp
         PROPERTIES SKIP_PRECOMPILE_HEADERS 1
 )
 

SpaceCadetPinball/imgui_impl_sdlrenderer.cpp

@@ -0,0 +1,251 @@
+// dear imgui: Renderer Backend for SDL_Renderer
+// (Requires: SDL 2.0.17+)
+
+// Important to understand: SDL_Renderer is an _optional_ component of SDL.
+// For a multi-platform app consider using e.g. SDL+DirectX on Windows and SDL+OpenGL on Linux/OSX.
+// If your application will want to render any non trivial amount of graphics other than UI,
+// please be aware that SDL_Renderer offers a limited graphic API to the end-user and it might
+// be difficult to step out of those boundaries.
+// However, we understand it is a convenient choice to get an app started easily.
+
+// Implemented features:
+//  [X] Renderer: User texture binding. Use 'SDL_Texture*' as ImTextureID. Read the FAQ about ImTextureID!
+//  [X] Renderer: Support for large meshes (64k+ vertices) with 16-bit indices.
+// Missing features:
+
+// You can copy and use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
+// If you are new to Dear ImGui, read documentation from the docs/ folder + read the top of imgui.cpp.
+// Read online: https://github.com/ocornut/imgui/tree/master/docs
+
+// CHANGELOG
+//  2022-10-11: Using 'nullptr' instead of 'NULL' as per our switch to C++11.
+//  2021-12-21: Update SDL_RenderGeometryRaw() format to work with SDL 2.0.19.
+//  2021-12-03: Added support for large mesh (64K+ vertices), enable ImGuiBackendFlags_RendererHasVtxOffset flag.
+//  2021-10-06: Backup and restore modified ClipRect/Viewport.
+//  2021-09-21: Initial version.
+
+#include "imgui.h"
+#include "imgui_impl_sdlrenderer.h"
+#if defined(_MSC_VER) && _MSC_VER <= 1500 // MSVC 2008 or earlier
+#include <stddef.h>     // intptr_t
+#else
+#include <stdint.h>     // intptr_t
+#endif
+
+// SDL
+#include <SDL.h>
+#if SDL_VERSION_ATLEAST(2,0,17)
+
+// SDL_Renderer data
+struct ImGui_ImplSDLRenderer_Data
+{
+    SDL_Renderer*   SDLRenderer;
+    SDL_Texture*    FontTexture;
+    ImGui_ImplSDLRenderer_Data() { memset((void*)this, 0, sizeof(*this)); }
+};
+
+// Backend data stored in io.BackendRendererUserData to allow support for multiple Dear ImGui contexts
+// It is STRONGLY preferred that you use docking branch with multi-viewports (== single Dear ImGui context + multiple windows) instead of multiple Dear ImGui contexts.
+static ImGui_ImplSDLRenderer_Data* ImGui_ImplSDLRenderer_GetBackendData()
+{
+    return ImGui::GetCurrentContext() ? (ImGui_ImplSDLRenderer_Data*)ImGui::GetIO().BackendRendererUserData : nullptr;
+}
+
+// Functions
+bool ImGui_ImplSDLRenderer_Init(SDL_Renderer* renderer)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    IM_ASSERT(io.BackendRendererUserData == nullptr && "Already initialized a renderer backend!");
+    IM_ASSERT(renderer != nullptr && "SDL_Renderer not initialized!");
+
+    // Setup backend capabilities flags
+    ImGui_ImplSDLRenderer_Data* bd = IM_NEW(ImGui_ImplSDLRenderer_Data)();
+    io.BackendRendererUserData = (void*)bd;
+    io.BackendRendererName = "imgui_impl_sdlrenderer";
+    io.BackendFlags |= ImGuiBackendFlags_RendererHasVtxOffset;  // We can honor the ImDrawCmd::VtxOffset field, allowing for large meshes.
+
+    bd->SDLRenderer = renderer;
+
+    return true;
+}
+
+void ImGui_ImplSDLRenderer_Shutdown()
+{
+    ImGui_ImplSDLRenderer_Data* bd = ImGui_ImplSDLRenderer_GetBackendData();
+    IM_ASSERT(bd != nullptr && "No renderer backend to shutdown, or already shutdown?");
+    ImGuiIO& io = ImGui::GetIO();
+
+    ImGui_ImplSDLRenderer_DestroyDeviceObjects();
+
+    io.BackendRendererName = nullptr;
+    io.BackendRendererUserData = nullptr;
+    IM_DELETE(bd);
+}
+
+static void ImGui_ImplSDLRenderer_SetupRenderState()
+{
+	ImGui_ImplSDLRenderer_Data* bd = ImGui_ImplSDLRenderer_GetBackendData();
+
+	// Clear out any viewports and cliprect set by the user
+    // FIXME: Technically speaking there are lots of other things we could backup/setup/restore during our render process.
+	SDL_RenderSetViewport(bd->SDLRenderer, nullptr);
+	SDL_RenderSetClipRect(bd->SDLRenderer, nullptr);
+}
+
+void ImGui_ImplSDLRenderer_NewFrame()
+{
+    ImGui_ImplSDLRenderer_Data* bd = ImGui_ImplSDLRenderer_GetBackendData();
+    IM_ASSERT(bd != nullptr && "Did you call ImGui_ImplSDLRenderer_Init()?");
+
+    if (!bd->FontTexture)
+        ImGui_ImplSDLRenderer_CreateDeviceObjects();
+}
+
+void ImGui_ImplSDLRenderer_RenderDrawData(ImDrawData* draw_data)
+{
+	ImGui_ImplSDLRenderer_Data* bd = ImGui_ImplSDLRenderer_GetBackendData();
+
+	// If there's a scale factor set by the user, use that instead
+    // If the user has specified a scale factor to SDL_Renderer already via SDL_RenderSetScale(), SDL will scale whatever we pass
+    // to SDL_RenderGeometryRaw() by that scale factor. In that case we don't want to be also scaling it ourselves here.
+    float rsx = 1.0f;
+	float rsy = 1.0f;
+	SDL_RenderGetScale(bd->SDLRenderer, &rsx, &rsy);
+    ImVec2 render_scale;
+	render_scale.x = (rsx == 1.0f) ? draw_data->FramebufferScale.x : 1.0f;
+	render_scale.y = (rsy == 1.0f) ? draw_data->FramebufferScale.y : 1.0f;
+
+	// Avoid rendering when minimized, scale coordinates for retina displays (screen coordinates != framebuffer coordinates)
+	int fb_width = (int)(draw_data->DisplaySize.x * render_scale.x);
+	int fb_height = (int)(draw_data->DisplaySize.y * render_scale.y);
+	if (fb_width == 0 || fb_height == 0)
+		return;
+
+    // Backup SDL_Renderer state that will be modified to restore it afterwards
+    struct BackupSDLRendererState
+    {
+        SDL_Rect    Viewport;
+        bool        ClipEnabled;
+        SDL_Rect    ClipRect;
+    };
+    BackupSDLRendererState old = {};
+    old.ClipEnabled = SDL_RenderIsClipEnabled(bd->SDLRenderer) == SDL_TRUE;
+    SDL_RenderGetViewport(bd->SDLRenderer, &old.Viewport);
+    SDL_RenderGetClipRect(bd->SDLRenderer, &old.ClipRect);
+
+	// Will project scissor/clipping rectangles into framebuffer space
+	ImVec2 clip_off = draw_data->DisplayPos;         // (0,0) unless using multi-viewports
+	ImVec2 clip_scale = render_scale;
+
+    // Render command lists
+    ImGui_ImplSDLRenderer_SetupRenderState();
+    for (int n = 0; n < draw_data->CmdListsCount; n++)
+    {
+        const ImDrawList* cmd_list = draw_data->CmdLists[n];
+        const ImDrawVert* vtx_buffer = cmd_list->VtxBuffer.Data;
+        const ImDrawIdx* idx_buffer = cmd_list->IdxBuffer.Data;
+
+        for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
+        {
+            const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
+            if (pcmd->UserCallback)
+            {
+                // User callback, registered via ImDrawList::AddCallback()
+                // (ImDrawCallback_ResetRenderState is a special callback value used by the user to request the renderer to reset render state.)
+                if (pcmd->UserCallback == ImDrawCallback_ResetRenderState)
+                    ImGui_ImplSDLRenderer_SetupRenderState();
+                else
+                    pcmd->UserCallback(cmd_list, pcmd);
+            }
+            else
+            {
+                // Project scissor/clipping rectangles into framebuffer space
+                ImVec2 clip_min((pcmd->ClipRect.x - clip_off.x) * clip_scale.x, (pcmd->ClipRect.y - clip_off.y) * clip_scale.y);
+                ImVec2 clip_max((pcmd->ClipRect.z - clip_off.x) * clip_scale.x, (pcmd->ClipRect.w - clip_off.y) * clip_scale.y);
+                if (clip_min.x < 0.0f) { clip_min.x = 0.0f; }
+                if (clip_min.y < 0.0f) { clip_min.y = 0.0f; }
+                if (clip_max.x > (float)fb_width) { clip_max.x = (float)fb_width; }
+                if (clip_max.y > (float)fb_height) { clip_max.y = (float)fb_height; }
+                if (clip_max.x <= clip_min.x || clip_max.y <= clip_min.y)
+                    continue;
+
+                SDL_Rect r = { (int)(clip_min.x), (int)(clip_min.y), (int)(clip_max.x - clip_min.x), (int)(clip_max.y - clip_min.y) };
+                SDL_RenderSetClipRect(bd->SDLRenderer, &r);
+
+                const float* xy = (const float*)(const void*)((const char*)(vtx_buffer + pcmd->VtxOffset) + IM_OFFSETOF(ImDrawVert, pos));
+                const float* uv = (const float*)(const void*)((const char*)(vtx_buffer + pcmd->VtxOffset) + IM_OFFSETOF(ImDrawVert, uv));
+#if SDL_VERSION_ATLEAST(2,0,19)
+                const SDL_Color* color = (const SDL_Color*)(const void*)((const char*)(vtx_buffer + pcmd->VtxOffset) + IM_OFFSETOF(ImDrawVert, col)); // SDL 2.0.19+
+#else
+                const int* color = (const int*)(const void*)((const char*)(vtx_buffer + pcmd->VtxOffset) + IM_OFFSETOF(ImDrawVert, col)); // SDL 2.0.17 and 2.0.18
+#endif
+
+                // Bind texture, Draw
+				SDL_Texture* tex = (SDL_Texture*)pcmd->GetTexID();
+                SDL_RenderGeometryRaw(bd->SDLRenderer, tex,
+                    xy, (int)sizeof(ImDrawVert),
+                    color, (int)sizeof(ImDrawVert),
+                    uv, (int)sizeof(ImDrawVert),
+                    cmd_list->VtxBuffer.Size - pcmd->VtxOffset,
+                    idx_buffer + pcmd->IdxOffset, pcmd->ElemCount, sizeof(ImDrawIdx));
+            }
+        }
+    }
+
+    // Restore modified SDL_Renderer state
+    SDL_RenderSetViewport(bd->SDLRenderer, &old.Viewport);
+    SDL_RenderSetClipRect(bd->SDLRenderer, old.ClipEnabled ? &old.ClipRect : nullptr);
+}
+
+// Called by Init/NewFrame/Shutdown
+bool ImGui_ImplSDLRenderer_CreateFontsTexture()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    ImGui_ImplSDLRenderer_Data* bd = ImGui_ImplSDLRenderer_GetBackendData();
+
+    // Build texture atlas
+    unsigned char* pixels;
+    int width, height;
+    io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height);   // Load as RGBA 32-bit (75% of the memory is wasted, but default font is so small) because it is more likely to be compatible with user's existing shaders. If your ImTextureId represent a higher-level concept than just a GL texture id, consider calling GetTexDataAsAlpha8() instead to save on GPU memory.
+
+    // Upload texture to graphics system
+    // (Bilinear sampling is required by default. Set 'io.Fonts->Flags |= ImFontAtlasFlags_NoBakedLines' or 'style.AntiAliasedLinesUseTex = false' to allow point/nearest sampling)
+    bd->FontTexture = SDL_CreateTexture(bd->SDLRenderer, SDL_PIXELFORMAT_ABGR8888, SDL_TEXTUREACCESS_STATIC, width, height);
+    if (bd->FontTexture == nullptr)
+    {
+        SDL_Log("error creating texture");
+        return false;
+    }
+    SDL_UpdateTexture(bd->FontTexture, nullptr, pixels, 4 * width);
+    SDL_SetTextureBlendMode(bd->FontTexture, SDL_BLENDMODE_BLEND);
+    SDL_SetTextureScaleMode(bd->FontTexture, SDL_ScaleModeLinear);
+
+    // Store our identifier
+    io.Fonts->SetTexID((ImTextureID)(intptr_t)bd->FontTexture);
+
+    return true;
+}
+
+void ImGui_ImplSDLRenderer_DestroyFontsTexture()
+{
+    ImGuiIO& io = ImGui::GetIO();
+    ImGui_ImplSDLRenderer_Data* bd = ImGui_ImplSDLRenderer_GetBackendData();
+    if (bd->FontTexture)
+    {
+        io.Fonts->SetTexID(0);
+        SDL_DestroyTexture(bd->FontTexture);
+        bd->FontTexture = nullptr;
+    }
+}
+
+bool ImGui_ImplSDLRenderer_CreateDeviceObjects()
+{
+    return ImGui_ImplSDLRenderer_CreateFontsTexture();
+}
+
+void ImGui_ImplSDLRenderer_DestroyDeviceObjects()
+{
+    ImGui_ImplSDLRenderer_DestroyFontsTexture();
+}
+
+#endif

SpaceCadetPinball/imgui_impl_sdlrenderer.h

@@ -0,0 +1,29 @@
+// dear imgui: Renderer Backend for SDL_Renderer
+// (Requires: SDL 2.0.17+)
+
+// Important to understand: SDL_Renderer is an _optional_ component of SDL.
+// For a multi-platform app consider using e.g. SDL+DirectX on Windows and SDL+OpenGL on Linux/OSX.
+// If your application will want to render any non trivial amount of graphics other than UI,
+// please be aware that SDL_Renderer offers a limited graphic API to the end-user and it might
+// be difficult to step out of those boundaries.
+// However, we understand it is a convenient choice to get an app started easily.
+
+// Implemented features:
+//  [X] Renderer: User texture binding. Use 'SDL_Texture*' as ImTextureID. Read the FAQ about ImTextureID!
+//  [X] Renderer: Support for large meshes (64k+ vertices) with 16-bit indices.
+
+#pragma once
+#include "imgui.h"      // IMGUI_IMPL_API
+
+struct SDL_Renderer;
+
+IMGUI_IMPL_API bool     ImGui_ImplSDLRenderer_Init(SDL_Renderer* renderer);
+IMGUI_IMPL_API void     ImGui_ImplSDLRenderer_Shutdown();
+IMGUI_IMPL_API void     ImGui_ImplSDLRenderer_NewFrame();
+IMGUI_IMPL_API void     ImGui_ImplSDLRenderer_RenderDrawData(ImDrawData* draw_data);
+
+// Called by Init/NewFrame/Shutdown
+IMGUI_IMPL_API bool     ImGui_ImplSDLRenderer_CreateFontsTexture();
+IMGUI_IMPL_API void     ImGui_ImplSDLRenderer_DestroyFontsTexture();
+IMGUI_IMPL_API bool     ImGui_ImplSDLRenderer_CreateDeviceObjects();
+IMGUI_IMPL_API void     ImGui_ImplSDLRenderer_DestroyDeviceObjects();

SpaceCadetPinball/pch.h

@@ -49,8 +49,25 @@ constexpr int MIX_INIT_MID_Proxy =
 #include "imgui.h"
 #include "imgui_internal.h"
 #include "imgui_impl_sdl.h"
+
+// imgui_impl_sdlrenderer is faster and more accurate, but it requires newer SDL.
+#if SDL_VERSION_ATLEAST(2, 0, 17)
+#include "imgui_impl_sdlrenderer.h"
+constexpr const char* ImGuiRender = "HW";
+inline void ImGui_Render_Init(SDL_Renderer* renderer) { ImGui_ImplSDLRenderer_Init(renderer); }
+inline void ImGui_Render_Shutdown() { ImGui_ImplSDLRenderer_Shutdown(); }
+inline void ImGui_Render_NewFrame() { ImGui_ImplSDLRenderer_NewFrame(); }
+inline void ImGui_Render_RenderDrawData(ImDrawData* draw_data) { ImGui_ImplSDLRenderer_RenderDrawData(draw_data); }
+#else
 //https://github.com/Tyyppi77/imgui_sdl 01deb04b102b6a1c15c7fdec1977a2c96a885e6f + patches
 #include "imgui_sdl.h"
+constexpr const char* ImGuiRender = "SW";
+inline void ImGui_Render_Init(SDL_Renderer* renderer) { ImGuiSDL::Initialize(renderer, 0, 0); }
+inline void ImGui_Render_Shutdown() { ImGuiSDL::Deinitialize(); }
+inline void ImGui_Render_NewFrame() { }
+inline void ImGui_Render_RenderDrawData(ImDrawData* draw_data) { ImGuiSDL::Render(draw_data); }
+#endif
+
 
 typedef char* LPSTR;
 typedef const char* LPCSTR;

SpaceCadetPinball/winmain.cpp

@@ -55,7 +55,7 @@ int winmain::WinMain(LPCSTR lpCmdLine)
 	printf("Command line: %s\n", lpCmdLine);
 	printf("Compiled with: SDL %d.%d.%d;", SDL_MAJOR_VERSION, SDL_MINOR_VERSION, SDL_PATCHLEVEL);
 	printf(" SDL_mixer %d.%d.%d;", SDL_MIXER_MAJOR_VERSION, SDL_MIXER_MINOR_VERSION, SDL_MIXER_PATCHLEVEL);
-	printf(" ImGui %s\n", IMGUI_VERSION);
+	printf(" ImGui %s %s\n", IMGUI_VERSION, ImGuiRender);
 
 	// SDL init
 	SDL_SetMainReady();
@@ -169,7 +169,7 @@ int winmain::WinMain(LPCSTR lpCmdLine)
 				printf("Failed to load font: %s, using embedded font.\n", fileName);
 			io.Fonts->Build();
 		}
-		ImGuiSDL::Initialize(renderer, 0, 0);
+		ImGui_Render_Init(renderer);
 		ImGui::StyleColorsDark();
 		
 		ImGui_ImplSDL2_InitForSDLRenderer(window, Renderer);
@@ -242,7 +242,7 @@ int winmain::WinMain(LPCSTR lpCmdLine)
 		Sound::Close();
 		pb::uninit();
 
-		ImGuiSDL::Deinitialize();
+		ImGui_Render_Shutdown();
 		ImGui_ImplSDL2_Shutdown();
 		ImGui::DestroyContext();
 	}
@@ -357,6 +357,7 @@ void winmain::MainLoop()
 			if (UpdateToFrameCounter >= UpdateToFrameRatio)
 			{
 				ImGui_ImplSDL2_NewFrame();
+				ImGui_Render_NewFrame();
 				ImGui::NewFrame();
 				RenderUi();
 
@@ -367,7 +368,7 @@ void winmain::MainLoop()
 				render::PresentVScreen();
 
 				ImGui::Render();
-				ImGuiSDL::Render(ImGui::GetDrawData());
+				ImGui_Render_RenderDrawData(ImGui::GetDrawData());
 
 				SDL_RenderPresent(Renderer);
 				frameCounter++;