mirror of
https://github.com/tildearrow/furnace.git
synced 2024-12-05 10:47:26 +00:00
5da54a7678
commit f8704cd085c4347f835c21dc12a3951924143872 with Furnace patches
259 lines
11 KiB
C++
259 lines
11 KiB
C++
// dear imgui: Renderer Backend for SDL_Renderer for SDL3
|
|
// (Requires: SDL 3.0.0+)
|
|
|
|
// Note how SDL_Renderer is an _optional_ component of SDL3.
|
|
// 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 currently offers a limited graphic API to the end-user and
|
|
// it might be difficult to step out of those boundaries.
|
|
|
|
// Implemented features:
|
|
// [X] Renderer: User texture binding. Use 'SDL_Texture*' as ImTextureID. Read the FAQ about ImTextureID!
|
|
// [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
|
|
// Missing features:
|
|
// [ ] Renderer: Multi-viewport support (multiple windows).
|
|
|
|
// 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
|
|
// 2023-05-30: Initial version.
|
|
|
|
#include "imgui.h"
|
|
#ifndef IMGUI_DISABLE
|
|
#include "imgui_impl_sdlrenderer3.h"
|
|
#include <stdint.h> // intptr_t
|
|
|
|
// Clang warnings with -Weverything
|
|
#if defined(__clang__)
|
|
#pragma clang diagnostic push
|
|
#pragma clang diagnostic ignored "-Wsign-conversion" // warning: implicit conversion changes signedness
|
|
#endif
|
|
|
|
// SDL
|
|
#include <SDL3/SDL.h>
|
|
#if !SDL_VERSION_ATLEAST(3,0,0)
|
|
#error This backend requires SDL 3.0.0+
|
|
#endif
|
|
|
|
// SDL_Renderer data
|
|
struct ImGui_ImplSDLRenderer3_Data
|
|
{
|
|
SDL_Renderer* SDLRenderer;
|
|
SDL_Texture* FontTexture;
|
|
ImGui_ImplSDLRenderer3_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_ImplSDLRenderer3_Data* ImGui_ImplSDLRenderer3_GetBackendData()
|
|
{
|
|
return ImGui::GetCurrentContext() ? (ImGui_ImplSDLRenderer3_Data*)ImGui::GetIO().BackendRendererUserData : nullptr;
|
|
}
|
|
|
|
// Functions
|
|
bool ImGui_ImplSDLRenderer3_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_ImplSDLRenderer3_Data* bd = IM_NEW(ImGui_ImplSDLRenderer3_Data)();
|
|
io.BackendRendererUserData = (void*)bd;
|
|
io.BackendRendererName = "imgui_impl_sdlrenderer3";
|
|
io.BackendFlags |= ImGuiBackendFlags_RendererHasVtxOffset; // We can honor the ImDrawCmd::VtxOffset field, allowing for large meshes.
|
|
|
|
bd->SDLRenderer = renderer;
|
|
|
|
return true;
|
|
}
|
|
|
|
void ImGui_ImplSDLRenderer3_Shutdown()
|
|
{
|
|
ImGui_ImplSDLRenderer3_Data* bd = ImGui_ImplSDLRenderer3_GetBackendData();
|
|
IM_ASSERT(bd != nullptr && "No renderer backend to shutdown, or already shutdown?");
|
|
ImGuiIO& io = ImGui::GetIO();
|
|
|
|
ImGui_ImplSDLRenderer3_DestroyDeviceObjects();
|
|
|
|
io.BackendRendererName = nullptr;
|
|
io.BackendRendererUserData = nullptr;
|
|
io.BackendFlags &= ~ImGuiBackendFlags_RendererHasVtxOffset;
|
|
IM_DELETE(bd);
|
|
}
|
|
|
|
static void ImGui_ImplSDLRenderer3_SetupRenderState()
|
|
{
|
|
ImGui_ImplSDLRenderer3_Data* bd = ImGui_ImplSDLRenderer3_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_SetRenderViewport(bd->SDLRenderer, nullptr);
|
|
SDL_SetRenderClipRect(bd->SDLRenderer, nullptr);
|
|
}
|
|
|
|
void ImGui_ImplSDLRenderer3_NewFrame()
|
|
{
|
|
ImGui_ImplSDLRenderer3_Data* bd = ImGui_ImplSDLRenderer3_GetBackendData();
|
|
IM_ASSERT(bd != nullptr && "Did you call ImGui_ImplSDLRenderer3_Init()?");
|
|
|
|
if (!bd->FontTexture)
|
|
ImGui_ImplSDLRenderer3_CreateDeviceObjects();
|
|
}
|
|
|
|
void ImGui_ImplSDLRenderer3_RenderDrawData(ImDrawData* draw_data)
|
|
{
|
|
ImGui_ImplSDLRenderer3_Data* bd = ImGui_ImplSDLRenderer3_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_GetRenderScale(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_RenderClipEnabled(bd->SDLRenderer) == SDL_TRUE;
|
|
SDL_GetRenderViewport(bd->SDLRenderer, &old.Viewport);
|
|
SDL_GetRenderClipRect(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_ImplSDLRenderer3_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_ImplSDLRenderer3_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_SetRenderClipRect(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_SetRenderViewport(bd->SDLRenderer, &old.Viewport);
|
|
SDL_SetRenderClipRect(bd->SDLRenderer, old.ClipEnabled ? &old.ClipRect : nullptr);
|
|
}
|
|
|
|
// Called by Init/NewFrame/Shutdown
|
|
bool ImGui_ImplSDLRenderer3_CreateFontsTexture()
|
|
{
|
|
ImGuiIO& io = ImGui::GetIO();
|
|
ImGui_ImplSDLRenderer3_Data* bd = ImGui_ImplSDLRenderer3_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_SCALEMODE_LINEAR);
|
|
|
|
// Store our identifier
|
|
io.Fonts->SetTexID((ImTextureID)(intptr_t)bd->FontTexture);
|
|
|
|
return true;
|
|
}
|
|
|
|
void ImGui_ImplSDLRenderer3_DestroyFontsTexture()
|
|
{
|
|
ImGuiIO& io = ImGui::GetIO();
|
|
ImGui_ImplSDLRenderer3_Data* bd = ImGui_ImplSDLRenderer3_GetBackendData();
|
|
if (bd->FontTexture)
|
|
{
|
|
io.Fonts->SetTexID(0);
|
|
SDL_DestroyTexture(bd->FontTexture);
|
|
bd->FontTexture = nullptr;
|
|
}
|
|
}
|
|
|
|
bool ImGui_ImplSDLRenderer3_CreateDeviceObjects()
|
|
{
|
|
return ImGui_ImplSDLRenderer3_CreateFontsTexture();
|
|
}
|
|
|
|
void ImGui_ImplSDLRenderer3_DestroyDeviceObjects()
|
|
{
|
|
ImGui_ImplSDLRenderer3_DestroyFontsTexture();
|
|
}
|
|
|
|
//-----------------------------------------------------------------------------
|
|
|
|
#if defined(__clang__)
|
|
#pragma clang diagnostic pop
|
|
#endif
|
|
|
|
#endif // #ifndef IMGUI_DISABLE
|