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Add SDL3 surface backend for ImGui example

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- Created imgui_impl_sdlsurface3.h and corresponding implementation file.
- Added Makefile for building the SDL3 surface example on Linux and macOS.
- Included README.md with build instructions for Windows, Linux, and macOS.
- Added build script for Windows (build_win32.bat) and Visual Studio project files.
- Implemented main application logic in main.cpp to demonstrate ImGui with SDL3 and surface rendering.
This commit is contained in:
moonpower
2026-03-13 13:23:18 +01:00
parent 00843f9ece
commit 2f2b8a1226
12 changed files with 1898 additions and 242 deletions
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backends/imgui_impl_sdlsurface2.cpp
+632 -241
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@@ -1,324 +1,715 @@
// imgui_impl_sdlsurface2.cpp
// CPU-only SDL_Surface backend for Dear ImGui
#include "imgui_impl_sdlsurface2.h"
#include "imgui.h"
#ifndef IMGUI_DISABLE
#include <SDL.h>
#include <cstring>
#include <stdint.h>
#include <algorithm>
#include <cmath>
#include <cstring>
// No clamp in C++11
template<typename T>
static inline T ImClamp(T v, T lo, T hi)
struct ImGui_ImplSDLSurface2_FastFormat32
{
if (v < lo) return lo;
if (v > hi) return hi;
return v;
Uint32 Rmask;
Uint32 Gmask;
Uint32 Bmask;
Uint32 Amask;
Uint8 Rshift;
Uint8 Gshift;
Uint8 Bshift;
Uint8 Ashift;
bool HasAlpha;
bool Valid;
ImGui_ImplSDLSurface2_FastFormat32() { memset((void*)this, 0, sizeof(*this)); }
};
struct ImGui_ImplSDLSurface2_SurfaceInfo
{
SDL_Surface* Surface;
Uint8* Pixels;
int Pitch;
int Width;
int Height;
SDL_PixelFormat* Format;
SDL_Palette* Palette;
ImGui_ImplSDLSurface2_FastFormat32 FastFormat;
bool IsFast;
ImGui_ImplSDLSurface2_SurfaceInfo() { memset((void*)this, 0, sizeof(*this)); }
};
struct ImGui_ImplSDLSurface2_Data
{
SDL_Surface* TargetSurface;
SDL_Surface* FontSurface;
ImGui_ImplSDLSurface2_SurfaceInfo TargetInfo;
ImGui_ImplSDLSurface2_Data() { memset((void*)this, 0, sizeof(*this)); }
};
struct ImGui_ImplSDLSurface2_RasterVertex
{
float X;
float Y;
float U;
float V;
float R;
float G;
float B;
float A;
};
static ImGui_ImplSDLSurface2_Data* ImGui_ImplSDLSurface2_GetBackendData()
{
return ImGui::GetCurrentContext() ? (ImGui_ImplSDLSurface2_Data*)ImGui::GetIO().BackendRendererUserData : nullptr;
}
static SDL_Surface* g_TargetSurface = nullptr;
static SDL_Surface* g_FontSurface = nullptr;
static inline Uint32 GetPixel(SDL_Surface* s, int x, int y)
static inline float ImGui_ImplSDLSurface2_Edge(float ax, float ay, float bx, float by, float px, float py)
{
Uint8* p = (Uint8*)s->pixels + y * s->pitch + x * s->format->BytesPerPixel;
switch (s->format->BytesPerPixel)
return (bx - ax) * (py - ay) - (by - ay) * (px - ax);
}
static inline int ImGui_ImplSDLSurface2_ClampInt(int v, int lo, int hi)
{
return (v < lo) ? lo : (v > hi ? hi : v);
}
static inline Uint8 ImGui_ImplSDLSurface2_ClampByte(float v)
{
if (v <= 0.0f)
return 0;
if (v >= 255.0f)
return 255;
return (Uint8)(v + 0.5f);
}
static inline Uint8 ImGui_ImplSDLSurface2_Mul255(Uint32 a, Uint32 b)
{
Uint32 t = a * b + 128;
return (Uint8)((t + (t >> 8)) >> 8);
}
static ImGui_ImplSDLSurface2_FastFormat32 ImGui_ImplSDLSurface2_BuildFastFormat(SDL_PixelFormat* format)
{
ImGui_ImplSDLSurface2_FastFormat32 out;
if (format == nullptr)
return out;
if (format->BitsPerPixel != 32 || format->BytesPerPixel != 4)
return out;
if (format->Rloss != 0 || format->Gloss != 0 || format->Bloss != 0)
return out;
if (format->Amask != 0 && format->Aloss != 0)
return out;
out.Rmask = format->Rmask;
out.Gmask = format->Gmask;
out.Bmask = format->Bmask;
out.Amask = format->Amask;
out.Rshift = format->Rshift;
out.Gshift = format->Gshift;
out.Bshift = format->Bshift;
out.Ashift = format->Ashift;
out.HasAlpha = format->Amask != 0;
out.Valid = true;
return out;
}
static bool ImGui_ImplSDLSurface2_CanUseFastPath(SDL_Surface* surface, const ImGui_ImplSDLSurface2_FastFormat32& format)
{
#ifdef IMGUI_IMPL_SDLSURFACE_DISABLE_FAST_PATH
IM_UNUSED(surface);
IM_UNUSED(format);
return false;
#else
if (surface == nullptr || !format.Valid)
return false;
if ((surface->pitch & 3) != 0)
return false;
if ((((uintptr_t)surface->pixels) & 3) != 0)
return false;
return true;
#endif
}
static void ImGui_ImplSDLSurface2_InitSurfaceInfo(ImGui_ImplSDLSurface2_SurfaceInfo* out, SDL_Surface* surface)
{
out->Surface = surface;
out->Pixels = surface ? (Uint8*)surface->pixels : nullptr;
out->Pitch = surface ? surface->pitch : 0;
out->Width = surface ? surface->w : 0;
out->Height = surface ? surface->h : 0;
out->Format = surface ? surface->format : nullptr;
out->Palette = (surface && surface->format) ? surface->format->palette : nullptr;
out->FastFormat = ImGui_ImplSDLSurface2_BuildFastFormat(out->Format);
out->IsFast = ImGui_ImplSDLSurface2_CanUseFastPath(surface, out->FastFormat);
}
static inline Uint32 ImGui_ImplSDLSurface2_ReadPixelRaw(const ImGui_ImplSDLSurface2_SurfaceInfo& surface, int x, int y)
{
const Uint8* p = surface.Pixels + y * surface.Pitch + x * surface.Format->BytesPerPixel;
switch (surface.Format->BytesPerPixel)
{
case 1: return *p;
case 2: return *(Uint16*)p;
case 3:
if (SDL_BYTEORDER == SDL_BIG_ENDIAN)
return (p[0] << 16) | (p[1] << 8) | p[2];
else
return p[0] | (p[1] << 8) | (p[2] << 16);
case 4: return *(Uint32*)p;
case 1:
return *p;
case 2:
return *(const Uint16*)p;
case 3:
if (SDL_BYTEORDER == SDL_BIG_ENDIAN)
return (Uint32)((p[0] << 16) | (p[1] << 8) | p[2]);
return (Uint32)(p[0] | (p[1] << 8) | (p[2] << 16));
case 4:
return *(const Uint32*)p;
default:
return 0;
}
return 0;
}
static inline void BlendPixel(SDL_Surface* s, int x, int y,
Uint8 sr, Uint8 sg, Uint8 sb, Uint8 sa)
static inline void ImGui_ImplSDLSurface2_WritePixelRaw(const ImGui_ImplSDLSurface2_SurfaceInfo& surface, int x, int y, Uint32 pixel)
{
if (!s || sa == 0) return;
if (x < 0 || y < 0 || x >= s->w || y >= s->h) return;
if (sa == 255)
Uint8* p = surface.Pixels + y * surface.Pitch + x * surface.Format->BytesPerPixel;
switch (surface.Format->BytesPerPixel)
{
Uint32 out_pix = SDL_MapRGBA(s->format, sr, sg, sb, sa);
Uint8* p = (Uint8*)s->pixels + y * s->pitch + x * s->format->BytesPerPixel;
switch (s->format->BytesPerPixel)
case 1:
*p = (Uint8)pixel;
return;
case 2:
*(Uint16*)p = (Uint16)pixel;
return;
case 3:
if (SDL_BYTEORDER == SDL_BIG_ENDIAN)
{
case 1: *p = (Uint8)out_pix; break;
case 2: *(Uint16*)p = (Uint16)out_pix; break;
case 3:
if (SDL_BYTEORDER == SDL_BIG_ENDIAN)
{
p[0] = (out_pix >> 16) & 0xFF;
p[1] = (out_pix >> 8) & 0xFF;
p[2] = out_pix & 0xFF;
}
else
{
p[0] = out_pix & 0xFF;
p[1] = (out_pix >> 8) & 0xFF;
p[2] = (out_pix >> 16) & 0xFF;
}
break;
case 4: *(Uint32*)p = out_pix; break;
p[0] = (Uint8)((pixel >> 16) & 0xFF);
p[1] = (Uint8)((pixel >> 8) & 0xFF);
p[2] = (Uint8)(pixel & 0xFF);
}
else
{
p[0] = (Uint8)(pixel & 0xFF);
p[1] = (Uint8)((pixel >> 8) & 0xFF);
p[2] = (Uint8)((pixel >> 16) & 0xFF);
}
return;
case 4:
*(Uint32*)p = pixel;
return;
default:
return;
}
}
static inline void ImGui_ImplSDLSurface2_UnpackFastRGBA(const ImGui_ImplSDLSurface2_FastFormat32& format, Uint32 pixel, Uint8* r, Uint8* g, Uint8* b, Uint8* a)
{
*r = (Uint8)((pixel & format.Rmask) >> format.Rshift);
*g = (Uint8)((pixel & format.Gmask) >> format.Gshift);
*b = (Uint8)((pixel & format.Bmask) >> format.Bshift);
*a = format.HasAlpha ? (Uint8)((pixel & format.Amask) >> format.Ashift) : 255;
}
static inline Uint32 ImGui_ImplSDLSurface2_PackFastRGBA(const ImGui_ImplSDLSurface2_FastFormat32& format, Uint8 r, Uint8 g, Uint8 b, Uint8 a)
{
Uint32 pixel = (((Uint32)r << format.Rshift) & format.Rmask)
| (((Uint32)g << format.Gshift) & format.Gmask)
| (((Uint32)b << format.Bshift) & format.Bmask);
if (format.HasAlpha)
pixel |= (((Uint32)a << format.Ashift) & format.Amask);
return pixel;
}
static inline void ImGui_ImplSDLSurface2_ReadPixelRGBA(const ImGui_ImplSDLSurface2_SurfaceInfo& surface, int x, int y, Uint8* r, Uint8* g, Uint8* b, Uint8* a)
{
if (surface.IsFast)
{
const Uint32* src = (const Uint32*)(surface.Pixels + y * surface.Pitch) + x;
ImGui_ImplSDLSurface2_UnpackFastRGBA(surface.FastFormat, *src, r, g, b, a);
return;
}
Uint32 dst_pix = GetPixel(s, x, y);
Uint8 dr, dg, db, da;
SDL_GetRGBA(dst_pix, s->format, &dr, &dg, &db, &da);
Uint32 pixel = ImGui_ImplSDLSurface2_ReadPixelRaw(surface, x, y);
SDL_GetRGBA(pixel, surface.Format, r, g, b, a);
}
Uint8 out_r = (Uint8)((sr * sa + dr * (255 - sa)) / 255);
Uint8 out_g = (Uint8)((sg * sa + dg * (255 - sa)) / 255);
Uint8 out_b = (Uint8)((sb * sa + db * (255 - sa)) / 255);
Uint8 out_a = (Uint8)((sa + (da * (255 - sa)) / 255));
Uint32 out_pix = SDL_MapRGBA(s->format, out_r, out_g, out_b, out_a);
Uint8* p = (Uint8*)s->pixels + y * s->pitch + x * s->format->BytesPerPixel;
switch (s->format->BytesPerPixel)
static inline void ImGui_ImplSDLSurface2_BlendPixelFast(const ImGui_ImplSDLSurface2_SurfaceInfo& target, Uint32* dst, Uint8 sr, Uint8 sg, Uint8 sb, Uint8 sa)
{
if (sa == 0)
return;
if (sa == 255)
{
case 1: *p = (Uint8)out_pix; break;
case 2: *(Uint16*)p = (Uint16)out_pix; break;
case 3:
if (SDL_BYTEORDER == SDL_BIG_ENDIAN)
*dst = ImGui_ImplSDLSurface2_PackFastRGBA(target.FastFormat, sr, sg, sb, 255);
return;
}
Uint8 dr, dg, db, da;
ImGui_ImplSDLSurface2_UnpackFastRGBA(target.FastFormat, *dst, &dr, &dg, &db, &da);
Uint8 inv_a = (Uint8)(255 - sa);
Uint8 out_r = (Uint8)(ImGui_ImplSDLSurface2_Mul255(sr, sa) + ImGui_ImplSDLSurface2_Mul255(dr, inv_a));
Uint8 out_g = (Uint8)(ImGui_ImplSDLSurface2_Mul255(sg, sa) + ImGui_ImplSDLSurface2_Mul255(dg, inv_a));
Uint8 out_b = (Uint8)(ImGui_ImplSDLSurface2_Mul255(sb, sa) + ImGui_ImplSDLSurface2_Mul255(db, inv_a));
Uint8 out_a = target.FastFormat.HasAlpha ? (Uint8)(sa + ImGui_ImplSDLSurface2_Mul255(da, inv_a)) : 255;
*dst = ImGui_ImplSDLSurface2_PackFastRGBA(target.FastFormat, out_r, out_g, out_b, out_a);
}
static inline void ImGui_ImplSDLSurface2_BlendPixelGeneric(const ImGui_ImplSDLSurface2_SurfaceInfo& target, int x, int y, Uint8 sr, Uint8 sg, Uint8 sb, Uint8 sa)
{
if (sa == 0)
return;
if (sa == 255)
{
Uint32 pixel = SDL_MapRGBA(target.Format, sr, sg, sb, 255);
ImGui_ImplSDLSurface2_WritePixelRaw(target, x, y, pixel);
return;
}
Uint8 dr, dg, db, da;
Uint32 dst_pixel = ImGui_ImplSDLSurface2_ReadPixelRaw(target, x, y);
SDL_GetRGBA(dst_pixel, target.Format, &dr, &dg, &db, &da);
Uint8 inv_a = (Uint8)(255 - sa);
Uint8 out_r = (Uint8)(ImGui_ImplSDLSurface2_Mul255(sr, sa) + ImGui_ImplSDLSurface2_Mul255(dr, inv_a));
Uint8 out_g = (Uint8)(ImGui_ImplSDLSurface2_Mul255(sg, sa) + ImGui_ImplSDLSurface2_Mul255(dg, inv_a));
Uint8 out_b = (Uint8)(ImGui_ImplSDLSurface2_Mul255(sb, sa) + ImGui_ImplSDLSurface2_Mul255(db, inv_a));
Uint8 out_a = target.Format->Amask ? (Uint8)(sa + ImGui_ImplSDLSurface2_Mul255(da, inv_a)) : 255;
Uint32 pixel = SDL_MapRGBA(target.Format, out_r, out_g, out_b, out_a);
ImGui_ImplSDLSurface2_WritePixelRaw(target, x, y, pixel);
}
static inline void ImGui_ImplSDLSurface2_SetupRasterVertex(ImGui_ImplSDLSurface2_RasterVertex* out, const ImDrawVert& v, const ImVec2& display_pos, const ImVec2& framebuffer_scale)
{
out->X = (v.pos.x - display_pos.x) * framebuffer_scale.x;
out->Y = (v.pos.y - display_pos.y) * framebuffer_scale.y;
out->U = v.uv.x;
out->V = v.uv.y;
out->R = (float)((v.col >> IM_COL32_R_SHIFT) & 0xFF);
out->G = (float)((v.col >> IM_COL32_G_SHIFT) & 0xFF);
out->B = (float)((v.col >> IM_COL32_B_SHIFT) & 0xFF);
out->A = (float)((v.col >> IM_COL32_A_SHIFT) & 0xFF);
}
static void ImGui_ImplSDLSurface2_RenderTriangleFast(const ImGui_ImplSDLSurface2_SurfaceInfo& target, const ImGui_ImplSDLSurface2_SurfaceInfo* texture, const ImGui_ImplSDLSurface2_RasterVertex& v0, const ImGui_ImplSDLSurface2_RasterVertex& v1, const ImGui_ImplSDLSurface2_RasterVertex& v2, int clip_min_x, int clip_min_y, int clip_max_x, int clip_max_y)
{
int min_x = std::max((int)std::floor(std::min(v0.X, std::min(v1.X, v2.X))), clip_min_x);
int min_y = std::max((int)std::floor(std::min(v0.Y, std::min(v1.Y, v2.Y))), clip_min_y);
int max_x = std::min((int)std::ceil(std::max(v0.X, std::max(v1.X, v2.X))) - 1, clip_max_x - 1);
int max_y = std::min((int)std::ceil(std::max(v0.Y, std::max(v1.Y, v2.Y))) - 1, clip_max_y - 1);
if (min_x > max_x || min_y > max_y)
return;
float area = ImGui_ImplSDLSurface2_Edge(v0.X, v0.Y, v1.X, v1.Y, v2.X, v2.Y);
if (area == 0.0f)
return;
float sign = (area < 0.0f) ? -1.0f : 1.0f;
area *= sign;
float e0_dx = (v1.Y - v2.Y) * sign;
float e0_dy = (v2.X - v1.X) * sign;
float e1_dx = (v2.Y - v0.Y) * sign;
float e1_dy = (v0.X - v2.X) * sign;
float e2_dx = (v0.Y - v1.Y) * sign;
float e2_dy = (v1.X - v0.X) * sign;
float inv_area = 1.0f / area;
float dw0_dx = e0_dx * inv_area;
float dw0_dy = e0_dy * inv_area;
float dw1_dx = e1_dx * inv_area;
float dw1_dy = e1_dy * inv_area;
float dw2_dx = e2_dx * inv_area;
float dw2_dy = e2_dy * inv_area;
float dr_dx = dw0_dx * v0.R + dw1_dx * v1.R + dw2_dx * v2.R;
float dg_dx = dw0_dx * v0.G + dw1_dx * v1.G + dw2_dx * v2.G;
float db_dx = dw0_dx * v0.B + dw1_dx * v1.B + dw2_dx * v2.B;
float da_dx = dw0_dx * v0.A + dw1_dx * v1.A + dw2_dx * v2.A;
float du_dx = dw0_dx * v0.U + dw1_dx * v1.U + dw2_dx * v2.U;
float dv_dx = dw0_dx * v0.V + dw1_dx * v1.V + dw2_dx * v2.V;
float dr_dy = dw0_dy * v0.R + dw1_dy * v1.R + dw2_dy * v2.R;
float dg_dy = dw0_dy * v0.G + dw1_dy * v1.G + dw2_dy * v2.G;
float db_dy = dw0_dy * v0.B + dw1_dy * v1.B + dw2_dy * v2.B;
float da_dy = dw0_dy * v0.A + dw1_dy * v1.A + dw2_dy * v2.A;
float du_dy = dw0_dy * v0.U + dw1_dy * v1.U + dw2_dy * v2.U;
float dv_dy = dw0_dy * v0.V + dw1_dy * v1.V + dw2_dy * v2.V;
float start_x = (float)min_x + 0.5f;
float start_y = (float)min_y + 0.5f;
float e0_row = ImGui_ImplSDLSurface2_Edge(v1.X, v1.Y, v2.X, v2.Y, start_x, start_y) * sign;
float e1_row = ImGui_ImplSDLSurface2_Edge(v2.X, v2.Y, v0.X, v0.Y, start_x, start_y) * sign;
float e2_row = ImGui_ImplSDLSurface2_Edge(v0.X, v0.Y, v1.X, v1.Y, start_x, start_y) * sign;
float w0_row = e0_row * inv_area;
float w1_row = e1_row * inv_area;
float w2_row = e2_row * inv_area;
float r_row = w0_row * v0.R + w1_row * v1.R + w2_row * v2.R;
float g_row = w0_row * v0.G + w1_row * v1.G + w2_row * v2.G;
float b_row = w0_row * v0.B + w1_row * v1.B + w2_row * v2.B;
float a_row = w0_row * v0.A + w1_row * v1.A + w2_row * v2.A;
float u_row = w0_row * v0.U + w1_row * v1.U + w2_row * v2.U;
float v_row = w0_row * v0.V + w1_row * v1.V + w2_row * v2.V;
int texture_max_x = texture ? (texture->Width - 1) : 0;
int texture_max_y = texture ? (texture->Height - 1) : 0;
for (int y = min_y; y <= max_y; y++)
{
float e0 = e0_row;
float e1 = e1_row;
float e2 = e2_row;
float r = r_row;
float g = g_row;
float b = b_row;
float a = a_row;
float u = u_row;
float v = v_row;
Uint32* dst = (Uint32*)(target.Pixels + y * target.Pitch) + min_x;
for (int x = min_x; x <= max_x; x++)
{
if (e0 >= 0.0f && e1 >= 0.0f && e2 >= 0.0f)
{
p[0] = (out_pix >> 16) & 0xFF;
p[1] = (out_pix >> 8) & 0xFF;
p[2] = out_pix & 0xFF;
Uint8 out_r = ImGui_ImplSDLSurface2_ClampByte(r);
Uint8 out_g = ImGui_ImplSDLSurface2_ClampByte(g);
Uint8 out_b = ImGui_ImplSDLSurface2_ClampByte(b);
Uint8 out_a = ImGui_ImplSDLSurface2_ClampByte(a);
if (texture != nullptr)
{
int tx = ImGui_ImplSDLSurface2_ClampInt((int)(u * (float)texture_max_x + 0.5f), 0, texture_max_x);
int ty = ImGui_ImplSDLSurface2_ClampInt((int)(v * (float)texture_max_y + 0.5f), 0, texture_max_y);
Uint8 tr, tg, tb, ta;
ImGui_ImplSDLSurface2_ReadPixelRGBA(*texture, tx, ty, &tr, &tg, &tb, &ta);
out_r = ImGui_ImplSDLSurface2_Mul255(out_r, tr);
out_g = ImGui_ImplSDLSurface2_Mul255(out_g, tg);
out_b = ImGui_ImplSDLSurface2_Mul255(out_b, tb);
out_a = ImGui_ImplSDLSurface2_Mul255(out_a, ta);
}
ImGui_ImplSDLSurface2_BlendPixelFast(target, dst, out_r, out_g, out_b, out_a);
}
else
{
p[0] = out_pix & 0xFF;
p[1] = (out_pix >> 8) & 0xFF;
p[2] = (out_pix >> 16) & 0xFF;
}
break;
case 4: *(Uint32*)p = out_pix; break;
dst++;
e0 += e0_dx;
e1 += e1_dx;
e2 += e2_dx;
r += dr_dx;
g += dg_dx;
b += db_dx;
a += da_dx;
u += du_dx;
v += dv_dx;
}
e0_row += e0_dy;
e1_row += e1_dy;
e2_row += e2_dy;
r_row += dr_dy;
g_row += dg_dy;
b_row += db_dy;
a_row += da_dy;
u_row += du_dy;
v_row += dv_dy;
}
}
static inline float Edge(const ImVec2& a, const ImVec2& b, float x, float y)
static void ImGui_ImplSDLSurface2_RenderTriangleGeneric(const ImGui_ImplSDLSurface2_SurfaceInfo& target, const ImGui_ImplSDLSurface2_SurfaceInfo* texture, const ImGui_ImplSDLSurface2_RasterVertex& v0, const ImGui_ImplSDLSurface2_RasterVertex& v1, const ImGui_ImplSDLSurface2_RasterVertex& v2, int clip_min_x, int clip_min_y, int clip_max_x, int clip_max_y)
{
return (b.x - a.x) * (y - a.y) - (b.y - a.y) * (x - a.x);
int min_x = std::max((int)std::floor(std::min(v0.X, std::min(v1.X, v2.X))), clip_min_x);
int min_y = std::max((int)std::floor(std::min(v0.Y, std::min(v1.Y, v2.Y))), clip_min_y);
int max_x = std::min((int)std::ceil(std::max(v0.X, std::max(v1.X, v2.X))) - 1, clip_max_x - 1);
int max_y = std::min((int)std::ceil(std::max(v0.Y, std::max(v1.Y, v2.Y))) - 1, clip_max_y - 1);
if (min_x > max_x || min_y > max_y)
return;
float area = ImGui_ImplSDLSurface2_Edge(v0.X, v0.Y, v1.X, v1.Y, v2.X, v2.Y);
if (area == 0.0f)
return;
float sign = (area < 0.0f) ? -1.0f : 1.0f;
area *= sign;
float e0_dx = (v1.Y - v2.Y) * sign;
float e0_dy = (v2.X - v1.X) * sign;
float e1_dx = (v2.Y - v0.Y) * sign;
float e1_dy = (v0.X - v2.X) * sign;
float e2_dx = (v0.Y - v1.Y) * sign;
float e2_dy = (v1.X - v0.X) * sign;
float inv_area = 1.0f / area;
float dw0_dx = e0_dx * inv_area;
float dw0_dy = e0_dy * inv_area;
float dw1_dx = e1_dx * inv_area;
float dw1_dy = e1_dy * inv_area;
float dw2_dx = e2_dx * inv_area;
float dw2_dy = e2_dy * inv_area;
float dr_dx = dw0_dx * v0.R + dw1_dx * v1.R + dw2_dx * v2.R;
float dg_dx = dw0_dx * v0.G + dw1_dx * v1.G + dw2_dx * v2.G;
float db_dx = dw0_dx * v0.B + dw1_dx * v1.B + dw2_dx * v2.B;
float da_dx = dw0_dx * v0.A + dw1_dx * v1.A + dw2_dx * v2.A;
float du_dx = dw0_dx * v0.U + dw1_dx * v1.U + dw2_dx * v2.U;
float dv_dx = dw0_dx * v0.V + dw1_dx * v1.V + dw2_dx * v2.V;
float dr_dy = dw0_dy * v0.R + dw1_dy * v1.R + dw2_dy * v2.R;
float dg_dy = dw0_dy * v0.G + dw1_dy * v1.G + dw2_dy * v2.G;
float db_dy = dw0_dy * v0.B + dw1_dy * v1.B + dw2_dy * v2.B;
float da_dy = dw0_dy * v0.A + dw1_dy * v1.A + dw2_dy * v2.A;
float du_dy = dw0_dy * v0.U + dw1_dy * v1.U + dw2_dy * v2.U;
float dv_dy = dw0_dy * v0.V + dw1_dy * v1.V + dw2_dy * v2.V;
float start_x = (float)min_x + 0.5f;
float start_y = (float)min_y + 0.5f;
float e0_row = ImGui_ImplSDLSurface2_Edge(v1.X, v1.Y, v2.X, v2.Y, start_x, start_y) * sign;
float e1_row = ImGui_ImplSDLSurface2_Edge(v2.X, v2.Y, v0.X, v0.Y, start_x, start_y) * sign;
float e2_row = ImGui_ImplSDLSurface2_Edge(v0.X, v0.Y, v1.X, v1.Y, start_x, start_y) * sign;
float w0_row = e0_row * inv_area;
float w1_row = e1_row * inv_area;
float w2_row = e2_row * inv_area;
float r_row = w0_row * v0.R + w1_row * v1.R + w2_row * v2.R;
float g_row = w0_row * v0.G + w1_row * v1.G + w2_row * v2.G;
float b_row = w0_row * v0.B + w1_row * v1.B + w2_row * v2.B;
float a_row = w0_row * v0.A + w1_row * v1.A + w2_row * v2.A;
float u_row = w0_row * v0.U + w1_row * v1.U + w2_row * v2.U;
float v_row = w0_row * v0.V + w1_row * v1.V + w2_row * v2.V;
int texture_max_x = texture ? (texture->Width - 1) : 0;
int texture_max_y = texture ? (texture->Height - 1) : 0;
for (int y = min_y; y <= max_y; y++)
{
float e0 = e0_row;
float e1 = e1_row;
float e2 = e2_row;
float r = r_row;
float g = g_row;
float b = b_row;
float a = a_row;
float u = u_row;
float v = v_row;
for (int x = min_x; x <= max_x; x++)
{
if (e0 >= 0.0f && e1 >= 0.0f && e2 >= 0.0f)
{
Uint8 out_r = ImGui_ImplSDLSurface2_ClampByte(r);
Uint8 out_g = ImGui_ImplSDLSurface2_ClampByte(g);
Uint8 out_b = ImGui_ImplSDLSurface2_ClampByte(b);
Uint8 out_a = ImGui_ImplSDLSurface2_ClampByte(a);
if (texture != nullptr)
{
int tx = ImGui_ImplSDLSurface2_ClampInt((int)(u * (float)texture_max_x + 0.5f), 0, texture_max_x);
int ty = ImGui_ImplSDLSurface2_ClampInt((int)(v * (float)texture_max_y + 0.5f), 0, texture_max_y);
Uint8 tr, tg, tb, ta;
ImGui_ImplSDLSurface2_ReadPixelRGBA(*texture, tx, ty, &tr, &tg, &tb, &ta);
out_r = ImGui_ImplSDLSurface2_Mul255(out_r, tr);
out_g = ImGui_ImplSDLSurface2_Mul255(out_g, tg);
out_b = ImGui_ImplSDLSurface2_Mul255(out_b, tb);
out_a = ImGui_ImplSDLSurface2_Mul255(out_a, ta);
}
ImGui_ImplSDLSurface2_BlendPixelGeneric(target, x, y, out_r, out_g, out_b, out_a);
}
e0 += e0_dx;
e1 += e1_dx;
e2 += e2_dx;
r += dr_dx;
g += dg_dx;
b += db_dx;
a += da_dx;
u += du_dx;
v += dv_dx;
}
e0_row += e0_dy;
e1_row += e1_dy;
e2_row += e2_dy;
r_row += dr_dy;
g_row += dg_dy;
b_row += db_dy;
a_row += da_dy;
u_row += du_dy;
v_row += dv_dy;
}
}
SDL_Surface* ImGui_ImplSDLSurface2_CreateFontAtlasSurface()
{
ImGuiIO& io = ImGui::GetIO();
unsigned char* pixels = nullptr;
int width = 0, height = 0;
int width = 0;
int height = 0;
io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height);
if (!pixels || width <= 0 || height <= 0) return nullptr;
if (pixels == nullptr || width <= 0 || height <= 0)
return nullptr;
SDL_Surface* surf = SDL_CreateRGBSurfaceWithFormat(0, width, height, 32, SDL_PIXELFORMAT_RGBA32);
if (!surf) return nullptr;
SDL_Surface* surface = SDL_CreateRGBSurfaceWithFormat(0, width, height, 32, SDL_PIXELFORMAT_RGBA32);
if (surface == nullptr)
return nullptr;
if (SDL_MUSTLOCK(surface) && SDL_LockSurface(surface) != 0)
{
SDL_FreeSurface(surface);
return nullptr;
}
SDL_LockSurface(surf);
std::memcpy(surf->pixels, pixels, width * height * 4);
SDL_UnlockSurface(surf);
SDL_SetSurfaceBlendMode(surf, SDL_BLENDMODE_NONE);
return surf;
for (int y = 0; y < height; y++)
memcpy((Uint8*)surface->pixels + y * surface->pitch, pixels + (size_t)y * (size_t)width * 4, (size_t)width * 4);
if (SDL_MUSTLOCK(surface))
SDL_UnlockSurface(surface);
SDL_SetSurfaceBlendMode(surface, SDL_BLENDMODE_NONE);
return surface;
}
bool ImGui_ImplSDLSurface2_Init(SDL_Surface* surface)
{
if (!surface) return false;
if (surface == nullptr)
return false;
ImGuiIO& io = ImGui::GetIO();
IM_ASSERT(io.BackendRendererName == nullptr && "Already initialized a renderer backend!");
IMGUI_CHECKVERSION();
IM_ASSERT(io.BackendRendererUserData == nullptr && "Already initialized a renderer backend!");
ImGui_ImplSDLSurface2_Data* bd = IM_NEW(ImGui_ImplSDLSurface2_Data)();
io.BackendRendererUserData = (void*)bd;
io.BackendRendererName = "imgui_impl_sdlsurface2";
g_TargetSurface = surface;
g_FontSurface = ImGui_ImplSDLSurface2_CreateFontAtlasSurface();
if (g_FontSurface)
{
if (g_TargetSurface && g_FontSurface->format->format != g_TargetSurface->format->format)
{
SDL_Surface* converted = SDL_ConvertSurfaceFormat(g_FontSurface, g_TargetSurface->format->format, 0);
if (converted)
{
SDL_FreeSurface(g_FontSurface);
g_FontSurface = converted;
}
}
ImGui::GetIO().Fonts->TexID = (ImTextureID)g_FontSurface;
}
bd->TargetSurface = surface;
ImGui_ImplSDLSurface2_InitSurfaceInfo(&bd->TargetInfo, surface);
bd->FontSurface = ImGui_ImplSDLSurface2_CreateFontAtlasSurface();
if (bd->FontSurface != nullptr)
io.Fonts->TexID = (ImTextureID)bd->FontSurface;
return true;
}
void ImGui_ImplSDLSurface2_Shutdown()
{
ImGui_ImplSDLSurface2_Data* bd = ImGui_ImplSDLSurface2_GetBackendData();
IM_ASSERT(bd != nullptr && "No renderer backend to shutdown, or already shutdown?");
ImGuiIO& io = ImGui::GetIO();
io.BackendRendererName = nullptr;
io.BackendFlags &= ~ImGuiBackendFlags_RendererHasTextures;
ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
ImGui::GetIO().Fonts->TexID = nullptr;
if (g_FontSurface)
{
SDL_FreeSurface(g_FontSurface);
g_FontSurface = nullptr;
}
g_TargetSurface = nullptr;
io.Fonts->TexID = nullptr;
io.BackendRendererName = nullptr;
io.BackendRendererUserData = nullptr;
platform_io.ClearRendererHandlers();
if (bd->FontSurface != nullptr)
SDL_FreeSurface(bd->FontSurface);
IM_DELETE(bd);
}
void ImGui_ImplSDLSurface2_NewFrame()
{
// noop
ImGui_ImplSDLSurface2_Data* bd = ImGui_ImplSDLSurface2_GetBackendData();
IM_ASSERT(bd != nullptr && "Context or backend not initialized! Did you call ImGui_ImplSDLSurface2_Init()?");
IM_UNUSED(bd);
}
void ImGui_ImplSDLSurface2_RenderDrawData(ImDrawData* draw_data)
{
if (!draw_data || !g_TargetSurface) return;
ImGui_ImplSDLSurface2_Data* bd = ImGui_ImplSDLSurface2_GetBackendData();
if (bd == nullptr || draw_data == nullptr || bd->TargetSurface == nullptr)
return;
if (SDL_MUSTLOCK(g_TargetSurface)) SDL_LockSurface(g_TargetSurface);
if (SDL_MUSTLOCK(bd->TargetSurface) && SDL_LockSurface(bd->TargetSurface) != 0)
return;
const ImVec2 display_pos = draw_data->DisplayPos;
const ImVec2 fb_scale = draw_data->FramebufferScale;
ImGui_ImplSDLSurface2_InitSurfaceInfo(&bd->TargetInfo, bd->TargetSurface);
if (bd->TargetInfo.Width <= 0 || bd->TargetInfo.Height <= 0)
{
if (SDL_MUSTLOCK(bd->TargetSurface))
SDL_UnlockSurface(bd->TargetSurface);
return;
}
const ImVec2 clip_off = draw_data->DisplayPos;
const ImVec2 clip_scale = draw_data->FramebufferScale;
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;
const ImDrawList* draw_list = draw_data->CmdLists[n];
const ImDrawVert* vtx_buffer = draw_list->VtxBuffer.Data;
const ImDrawIdx* idx_buffer = draw_list->IdxBuffer.Data;
int idx_offset = 0;
for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
for (int cmd_i = 0; cmd_i < draw_list->CmdBuffer.Size; cmd_i++)
{
const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
const ImDrawCmd* pcmd = &draw_list->CmdBuffer[cmd_i];
if (pcmd->UserCallback != nullptr)
{
if (pcmd->UserCallback != ImDrawCallback_ResetRenderState)
pcmd->UserCallback(draw_list, pcmd);
continue;
}
if (pcmd->ElemCount == 0)
continue;
ImVec2 clip_min = ImVec2(
(pcmd->ClipRect.x - display_pos.x) * fb_scale.x,
(pcmd->ClipRect.y - display_pos.y) * fb_scale.y);
ImVec2 clip_max = ImVec2(
(pcmd->ClipRect.z - display_pos.x) * fb_scale.x,
(pcmd->ClipRect.w - display_pos.y) * fb_scale.y);
int cx0 = (int)std::floor(clip_min.x);
int cy0 = (int)std::floor(clip_min.y);
int cx1 = (int)std::ceil (clip_max.x);
int cy1 = (int)std::ceil (clip_max.y);
cx0 = std::max(cx0, 0);
cy0 = std::max(cy0, 0);
cx1 = std::min(cx1, g_TargetSurface->w);
cy1 = std::min(cy1, g_TargetSurface->h);
if (cx0 >= cx1 || cy0 >= cy1)
{
idx_offset += pcmd->ElemCount;
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)bd->TargetInfo.Width) clip_max.x = (float)bd->TargetInfo.Width;
if (clip_max.y > (float)bd->TargetInfo.Height) clip_max.y = (float)bd->TargetInfo.Height;
if (clip_max.x <= clip_min.x || clip_max.y <= clip_min.y)
continue;
}
SDL_Rect srect{ cx0, cy0, cx1 - cx0, cy1 - cy0 };
SDL_SetClipRect(g_TargetSurface, &srect);
int clip_min_x = (int)clip_min.x;
int clip_min_y = (int)clip_min.y;
int clip_max_x = (int)clip_max.x;
int clip_max_y = (int)clip_max.y;
SDL_Surface* tex = (SDL_Surface*)pcmd->GetTexID();
SDL_Surface* texture_surface = (SDL_Surface*)pcmd->GetTexID();
ImGui_ImplSDLSurface2_SurfaceInfo texture_info;
ImGui_ImplSDLSurface2_SurfaceInfo* texture_ptr = nullptr;
bool texture_locked = false;
for (unsigned int i = 0; i + 2 < (unsigned int)pcmd->ElemCount; i += 3)
if (texture_surface != nullptr)
{
ImDrawIdx i0 = idx_buffer[idx_offset + i + 0];
ImDrawIdx i1 = idx_buffer[idx_offset + i + 1];
ImDrawIdx i2 = idx_buffer[idx_offset + i + 2];
const ImDrawVert& v0 = vtx_buffer[i0];
const ImDrawVert& v1 = vtx_buffer[i1];
const ImDrawVert& v2 = vtx_buffer[i2];
ImVec2 p0 = ImVec2((v0.pos.x - display_pos.x) * fb_scale.x, (v0.pos.y - display_pos.y) * fb_scale.y);
ImVec2 p1 = ImVec2((v1.pos.x - display_pos.x) * fb_scale.x, (v1.pos.y - display_pos.y) * fb_scale.y);
ImVec2 p2 = ImVec2((v2.pos.x - display_pos.x) * fb_scale.x, (v2.pos.y - display_pos.y) * fb_scale.y);
int minx = (int)std::floor(std::min({ p0.x, p1.x, p2.x }));
int miny = (int)std::floor(std::min({ p0.y, p1.y, p2.y }));
int maxx = (int)std::ceil (std::max({ p0.x, p1.x, p2.x }));
int maxy = (int)std::ceil (std::max({ p0.y, p1.y, p2.y }));
minx = std::max(minx, cx0);
miny = std::max(miny, cy0);
maxx = std::min(maxx, cx1 - 1);
maxy = std::min(maxy, cy1 - 1);
if (minx > maxx || miny > maxy) continue;
float area = Edge(p0, p1, p2.x, p2.y);
if (area == 0.0f) continue;
auto unpack_col = [](ImU32 c, float out[4]) {
out[0] = (float)((c >> IM_COL32_R_SHIFT) & 0xFF) / 255.0f;
out[1] = (float)((c >> IM_COL32_G_SHIFT) & 0xFF) / 255.0f;
out[2] = (float)((c >> IM_COL32_B_SHIFT) & 0xFF) / 255.0f;
out[3] = (float)((c >> IM_COL32_A_SHIFT) & 0xFF) / 255.0f;
};
float c0[4], c1[4], c2[4];
unpack_col(v0.col, c0); unpack_col(v1.col, c1); unpack_col(v2.col, c2);
for (int y = miny; y <= maxy; y++)
if (SDL_MUSTLOCK(texture_surface))
{
for (int x = minx; x <= maxx; x++)
{
float px = (float)x + 0.5f;
float py = (float)y + 0.5f;
float w0 = Edge(p1, p2, px, py) / area;
float w1 = Edge(p2, p0, px, py) / area;
float w2 = Edge(p0, p1, px, py) / area;
if (w0 < 0.0f || w1 < 0.0f || w2 < 0.0f) continue;
float r = w0 * c0[0] + w1 * c1[0] + w2 * c2[0];
float g = w0 * c0[1] + w1 * c1[1] + w2 * c2[1];
float b = w0 * c0[2] + w1 * c1[2] + w2 * c2[2];
float a = w0 * c0[3] + w1 * c1[3] + w2 * c2[3];
Uint8 out_r = (Uint8)(ImClamp(r, 0.0f, 1.0f) * 255.0f);
Uint8 out_g = (Uint8)(ImClamp(g, 0.0f, 1.0f) * 255.0f);
Uint8 out_b = (Uint8)(ImClamp(b, 0.0f, 1.0f) * 255.0f);
Uint8 out_a = (Uint8)(ImClamp(a, 0.0f, 1.0f) * 255.0f);
if (tex)
{
ImVec2 uv0 = v0.uv, uv1 = v1.uv, uv2 = v2.uv;
float u = w0 * uv0.x + w1 * uv1.x + w2 * uv2.x;
float v = w0 * uv0.y + w1 * uv1.y + w2 * uv2.y;
int tx = (int)(u * (tex->w - 1) + 0.5f);
int ty = (int)(v * (tex->h - 1) + 0.5f);
tx = ImClamp(tx, 0, tex->w - 1);
ty = ImClamp(ty, 0, tex->h - 1);
Uint32 tpx = GetPixel(tex, tx, ty);
Uint8 tr, tg, tb, ta;
SDL_GetRGBA(tpx, tex->format, &tr, &tg, &tb, &ta);
Uint8 final_r = (Uint8)((tr * out_r) / 255);
Uint8 final_g = (Uint8)((tg * out_g) / 255);
Uint8 final_b = (Uint8)((tb * out_b) / 255);
Uint8 final_a = (Uint8)((ta * out_a) / 255);
BlendPixel(g_TargetSurface, x, y, final_r, final_g, final_b, final_a);
}
else
{
BlendPixel(g_TargetSurface, x, y, out_r, out_g, out_b, out_a);
}
}
if (SDL_LockSurface(texture_surface) != 0)
texture_surface = nullptr;
else
texture_locked = true;
}
if (texture_surface != nullptr)
{
ImGui_ImplSDLSurface2_InitSurfaceInfo(&texture_info, texture_surface);
if (texture_info.Width > 0 && texture_info.Height > 0)
texture_ptr = &texture_info;
}
}
idx_offset += pcmd->ElemCount;
for (unsigned int idx = 0; idx + 2 < (unsigned int)pcmd->ElemCount; idx += 3)
{
ImDrawIdx idx0 = idx_buffer[pcmd->IdxOffset + idx + 0];
ImDrawIdx idx1 = idx_buffer[pcmd->IdxOffset + idx + 1];
ImDrawIdx idx2 = idx_buffer[pcmd->IdxOffset + idx + 2];
ImGui_ImplSDLSurface2_RasterVertex v0;
ImGui_ImplSDLSurface2_RasterVertex v1;
ImGui_ImplSDLSurface2_RasterVertex v2;
ImGui_ImplSDLSurface2_SetupRasterVertex(&v0, vtx_buffer[pcmd->VtxOffset + idx0], clip_off, clip_scale);
ImGui_ImplSDLSurface2_SetupRasterVertex(&v1, vtx_buffer[pcmd->VtxOffset + idx1], clip_off, clip_scale);
ImGui_ImplSDLSurface2_SetupRasterVertex(&v2, vtx_buffer[pcmd->VtxOffset + idx2], clip_off, clip_scale);
if (bd->TargetInfo.IsFast)
ImGui_ImplSDLSurface2_RenderTriangleFast(bd->TargetInfo, texture_ptr, v0, v1, v2, clip_min_x, clip_min_y, clip_max_x, clip_max_y);
else
ImGui_ImplSDLSurface2_RenderTriangleGeneric(bd->TargetInfo, texture_ptr, v0, v1, v2, clip_min_x, clip_min_y, clip_max_x, clip_max_y);
}
if (texture_locked)
SDL_UnlockSurface(texture_surface);
}
}
SDL_SetClipRect(g_TargetSurface, nullptr);
if (SDL_MUSTLOCK(g_TargetSurface)) SDL_UnlockSurface(g_TargetSurface);
if (SDL_MUSTLOCK(bd->TargetSurface))
SDL_UnlockSurface(bd->TargetSurface);
}
#endif
backends/imgui_impl_sdlsurface3.cpp
+715
View File
@@ -0,0 +1,715 @@
#include "imgui_impl_sdlsurface3.h"
#include "imgui.h"
#ifndef IMGUI_DISABLE
#include <SDL3/SDL.h>
#include <stdint.h>
#include <algorithm>
#include <cmath>
#include <cstring>
struct ImGui_ImplSDLSurface3_FastFormat32
{
Uint32 Rmask;
Uint32 Gmask;
Uint32 Bmask;
Uint32 Amask;
Uint8 Rshift;
Uint8 Gshift;
Uint8 Bshift;
Uint8 Ashift;
bool HasAlpha;
bool Valid;
ImGui_ImplSDLSurface3_FastFormat32() { memset((void*)this, 0, sizeof(*this)); }
};
struct ImGui_ImplSDLSurface3_SurfaceInfo
{
SDL_Surface* Surface;
Uint8* Pixels;
int Pitch;
int Width;
int Height;
const SDL_PixelFormatDetails* Format;
SDL_Palette* Palette;
ImGui_ImplSDLSurface3_FastFormat32 FastFormat;
bool IsFast;
ImGui_ImplSDLSurface3_SurfaceInfo() { memset((void*)this, 0, sizeof(*this)); }
};
struct ImGui_ImplSDLSurface3_Data
{
SDL_Surface* TargetSurface;
SDL_Surface* FontSurface;
ImGui_ImplSDLSurface3_SurfaceInfo TargetInfo;
ImGui_ImplSDLSurface3_Data() { memset((void*)this, 0, sizeof(*this)); }
};
struct ImGui_ImplSDLSurface3_RasterVertex
{
float X;
float Y;
float U;
float V;
float R;
float G;
float B;
float A;
};
static ImGui_ImplSDLSurface3_Data* ImGui_ImplSDLSurface3_GetBackendData()
{
return ImGui::GetCurrentContext() ? (ImGui_ImplSDLSurface3_Data*)ImGui::GetIO().BackendRendererUserData : nullptr;
}
static inline float ImGui_ImplSDLSurface3_Edge(float ax, float ay, float bx, float by, float px, float py)
{
return (bx - ax) * (py - ay) - (by - ay) * (px - ax);
}
static inline int ImGui_ImplSDLSurface3_ClampInt(int v, int lo, int hi)
{
return (v < lo) ? lo : (v > hi ? hi : v);
}
static inline Uint8 ImGui_ImplSDLSurface3_ClampByte(float v)
{
if (v <= 0.0f)
return 0;
if (v >= 255.0f)
return 255;
return (Uint8)(v + 0.5f);
}
static inline Uint8 ImGui_ImplSDLSurface3_Mul255(Uint32 a, Uint32 b)
{
Uint32 t = a * b + 128;
return (Uint8)((t + (t >> 8)) >> 8);
}
static ImGui_ImplSDLSurface3_FastFormat32 ImGui_ImplSDLSurface3_BuildFastFormat(const SDL_PixelFormatDetails* format)
{
ImGui_ImplSDLSurface3_FastFormat32 out;
if (format == nullptr)
return out;
if (format->bits_per_pixel != 32 || format->bytes_per_pixel != 4)
return out;
if (format->Rbits != 8 || format->Gbits != 8 || format->Bbits != 8)
return out;
if (format->Amask != 0 && format->Abits != 8)
return out;
out.Rmask = format->Rmask;
out.Gmask = format->Gmask;
out.Bmask = format->Bmask;
out.Amask = format->Amask;
out.Rshift = format->Rshift;
out.Gshift = format->Gshift;
out.Bshift = format->Bshift;
out.Ashift = format->Ashift;
out.HasAlpha = format->Amask != 0;
out.Valid = true;
return out;
}
static bool ImGui_ImplSDLSurface3_CanUseFastPath(SDL_Surface* surface, const ImGui_ImplSDLSurface3_FastFormat32& format)
{
#ifdef IMGUI_IMPL_SDLSURFACE_DISABLE_FAST_PATH
IM_UNUSED(surface);
IM_UNUSED(format);
return false;
#else
if (surface == nullptr || !format.Valid)
return false;
if ((surface->pitch & 3) != 0)
return false;
if ((((uintptr_t)surface->pixels) & 3) != 0)
return false;
return true;
#endif
}
static void ImGui_ImplSDLSurface3_InitSurfaceInfo(ImGui_ImplSDLSurface3_SurfaceInfo* out, SDL_Surface* surface)
{
out->Surface = surface;
out->Pixels = surface ? (Uint8*)surface->pixels : nullptr;
out->Pitch = surface ? surface->pitch : 0;
out->Width = surface ? surface->w : 0;
out->Height = surface ? surface->h : 0;
out->Format = surface ? SDL_GetPixelFormatDetails(surface->format) : nullptr;
out->Palette = surface ? SDL_GetSurfacePalette(surface) : nullptr;
out->FastFormat = ImGui_ImplSDLSurface3_BuildFastFormat(out->Format);
out->IsFast = ImGui_ImplSDLSurface3_CanUseFastPath(surface, out->FastFormat);
}
static inline Uint32 ImGui_ImplSDLSurface3_ReadPixelRaw(const ImGui_ImplSDLSurface3_SurfaceInfo& surface, int x, int y)
{
const Uint8* p = surface.Pixels + y * surface.Pitch + x * surface.Format->bytes_per_pixel;
switch (surface.Format->bytes_per_pixel)
{
case 1:
return *p;
case 2:
return *(const Uint16*)p;
case 3:
if (SDL_BYTEORDER == SDL_BIG_ENDIAN)
return (Uint32)((p[0] << 16) | (p[1] << 8) | p[2]);
return (Uint32)(p[0] | (p[1] << 8) | (p[2] << 16));
case 4:
return *(const Uint32*)p;
default:
return 0;
}
}
static inline void ImGui_ImplSDLSurface3_WritePixelRaw(const ImGui_ImplSDLSurface3_SurfaceInfo& surface, int x, int y, Uint32 pixel)
{
Uint8* p = surface.Pixels + y * surface.Pitch + x * surface.Format->bytes_per_pixel;
switch (surface.Format->bytes_per_pixel)
{
case 1:
*p = (Uint8)pixel;
return;
case 2:
*(Uint16*)p = (Uint16)pixel;
return;
case 3:
if (SDL_BYTEORDER == SDL_BIG_ENDIAN)
{
p[0] = (Uint8)((pixel >> 16) & 0xFF);
p[1] = (Uint8)((pixel >> 8) & 0xFF);
p[2] = (Uint8)(pixel & 0xFF);
}
else
{
p[0] = (Uint8)(pixel & 0xFF);
p[1] = (Uint8)((pixel >> 8) & 0xFF);
p[2] = (Uint8)((pixel >> 16) & 0xFF);
}
return;
case 4:
*(Uint32*)p = pixel;
return;
default:
return;
}
}
static inline void ImGui_ImplSDLSurface3_UnpackFastRGBA(const ImGui_ImplSDLSurface3_FastFormat32& format, Uint32 pixel, Uint8* r, Uint8* g, Uint8* b, Uint8* a)
{
*r = (Uint8)((pixel & format.Rmask) >> format.Rshift);
*g = (Uint8)((pixel & format.Gmask) >> format.Gshift);
*b = (Uint8)((pixel & format.Bmask) >> format.Bshift);
*a = format.HasAlpha ? (Uint8)((pixel & format.Amask) >> format.Ashift) : 255;
}
static inline Uint32 ImGui_ImplSDLSurface3_PackFastRGBA(const ImGui_ImplSDLSurface3_FastFormat32& format, Uint8 r, Uint8 g, Uint8 b, Uint8 a)
{
Uint32 pixel = (((Uint32)r << format.Rshift) & format.Rmask)
| (((Uint32)g << format.Gshift) & format.Gmask)
| (((Uint32)b << format.Bshift) & format.Bmask);
if (format.HasAlpha)
pixel |= (((Uint32)a << format.Ashift) & format.Amask);
return pixel;
}
static inline void ImGui_ImplSDLSurface3_ReadPixelRGBA(const ImGui_ImplSDLSurface3_SurfaceInfo& surface, int x, int y, Uint8* r, Uint8* g, Uint8* b, Uint8* a)
{
if (surface.IsFast)
{
const Uint32* src = (const Uint32*)(surface.Pixels + y * surface.Pitch) + x;
ImGui_ImplSDLSurface3_UnpackFastRGBA(surface.FastFormat, *src, r, g, b, a);
return;
}
Uint32 pixel = ImGui_ImplSDLSurface3_ReadPixelRaw(surface, x, y);
SDL_GetRGBA(pixel, surface.Format, surface.Palette, r, g, b, a);
}
static inline void ImGui_ImplSDLSurface3_BlendPixelFast(const ImGui_ImplSDLSurface3_SurfaceInfo& target, Uint32* dst, Uint8 sr, Uint8 sg, Uint8 sb, Uint8 sa)
{
if (sa == 0)
return;
if (sa == 255)
{
*dst = ImGui_ImplSDLSurface3_PackFastRGBA(target.FastFormat, sr, sg, sb, 255);
return;
}
Uint8 dr, dg, db, da;
ImGui_ImplSDLSurface3_UnpackFastRGBA(target.FastFormat, *dst, &dr, &dg, &db, &da);
Uint8 inv_a = (Uint8)(255 - sa);
Uint8 out_r = (Uint8)(ImGui_ImplSDLSurface3_Mul255(sr, sa) + ImGui_ImplSDLSurface3_Mul255(dr, inv_a));
Uint8 out_g = (Uint8)(ImGui_ImplSDLSurface3_Mul255(sg, sa) + ImGui_ImplSDLSurface3_Mul255(dg, inv_a));
Uint8 out_b = (Uint8)(ImGui_ImplSDLSurface3_Mul255(sb, sa) + ImGui_ImplSDLSurface3_Mul255(db, inv_a));
Uint8 out_a = (target.Format != nullptr && target.Format->Amask != 0) ? (Uint8)(sa + ImGui_ImplSDLSurface3_Mul255(da, inv_a)) : 255;
*dst = ImGui_ImplSDLSurface3_PackFastRGBA(target.FastFormat, out_r, out_g, out_b, out_a);
}
static inline void ImGui_ImplSDLSurface3_BlendPixelGeneric(const ImGui_ImplSDLSurface3_SurfaceInfo& target, int x, int y, Uint8 sr, Uint8 sg, Uint8 sb, Uint8 sa)
{
if (sa == 0)
return;
if (sa == 255)
{
Uint32 pixel = SDL_MapRGBA(target.Format, target.Palette, sr, sg, sb, 255);
ImGui_ImplSDLSurface3_WritePixelRaw(target, x, y, pixel);
return;
}
Uint8 dr, dg, db, da;
Uint32 dst_pixel = ImGui_ImplSDLSurface3_ReadPixelRaw(target, x, y);
SDL_GetRGBA(dst_pixel, target.Format, target.Palette, &dr, &dg, &db, &da);
Uint8 inv_a = (Uint8)(255 - sa);
Uint8 out_r = (Uint8)(ImGui_ImplSDLSurface3_Mul255(sr, sa) + ImGui_ImplSDLSurface3_Mul255(dr, inv_a));
Uint8 out_g = (Uint8)(ImGui_ImplSDLSurface3_Mul255(sg, sa) + ImGui_ImplSDLSurface3_Mul255(dg, inv_a));
Uint8 out_b = (Uint8)(ImGui_ImplSDLSurface3_Mul255(sb, sa) + ImGui_ImplSDLSurface3_Mul255(db, inv_a));
Uint8 out_a = target.FastFormat.HasAlpha ? (Uint8)(sa + ImGui_ImplSDLSurface3_Mul255(da, inv_a)) : 255;
Uint32 pixel = SDL_MapRGBA(target.Format, target.Palette, out_r, out_g, out_b, out_a);
ImGui_ImplSDLSurface3_WritePixelRaw(target, x, y, pixel);
}
static inline void ImGui_ImplSDLSurface3_SetupRasterVertex(ImGui_ImplSDLSurface3_RasterVertex* out, const ImDrawVert& v, const ImVec2& display_pos, const ImVec2& framebuffer_scale)
{
out->X = (v.pos.x - display_pos.x) * framebuffer_scale.x;
out->Y = (v.pos.y - display_pos.y) * framebuffer_scale.y;
out->U = v.uv.x;
out->V = v.uv.y;
out->R = (float)((v.col >> IM_COL32_R_SHIFT) & 0xFF);
out->G = (float)((v.col >> IM_COL32_G_SHIFT) & 0xFF);
out->B = (float)((v.col >> IM_COL32_B_SHIFT) & 0xFF);
out->A = (float)((v.col >> IM_COL32_A_SHIFT) & 0xFF);
}
static void ImGui_ImplSDLSurface3_RenderTriangleFast(const ImGui_ImplSDLSurface3_SurfaceInfo& target, const ImGui_ImplSDLSurface3_SurfaceInfo* texture, const ImGui_ImplSDLSurface3_RasterVertex& v0, const ImGui_ImplSDLSurface3_RasterVertex& v1, const ImGui_ImplSDLSurface3_RasterVertex& v2, int clip_min_x, int clip_min_y, int clip_max_x, int clip_max_y)
{
int min_x = std::max((int)std::floor(std::min(v0.X, std::min(v1.X, v2.X))), clip_min_x);
int min_y = std::max((int)std::floor(std::min(v0.Y, std::min(v1.Y, v2.Y))), clip_min_y);
int max_x = std::min((int)std::ceil(std::max(v0.X, std::max(v1.X, v2.X))) - 1, clip_max_x - 1);
int max_y = std::min((int)std::ceil(std::max(v0.Y, std::max(v1.Y, v2.Y))) - 1, clip_max_y - 1);
if (min_x > max_x || min_y > max_y)
return;
float area = ImGui_ImplSDLSurface3_Edge(v0.X, v0.Y, v1.X, v1.Y, v2.X, v2.Y);
if (area == 0.0f)
return;
float sign = (area < 0.0f) ? -1.0f : 1.0f;
area *= sign;
float e0_dx = (v1.Y - v2.Y) * sign;
float e0_dy = (v2.X - v1.X) * sign;
float e1_dx = (v2.Y - v0.Y) * sign;
float e1_dy = (v0.X - v2.X) * sign;
float e2_dx = (v0.Y - v1.Y) * sign;
float e2_dy = (v1.X - v0.X) * sign;
float inv_area = 1.0f / area;
float dw0_dx = e0_dx * inv_area;
float dw0_dy = e0_dy * inv_area;
float dw1_dx = e1_dx * inv_area;
float dw1_dy = e1_dy * inv_area;
float dw2_dx = e2_dx * inv_area;
float dw2_dy = e2_dy * inv_area;
float dr_dx = dw0_dx * v0.R + dw1_dx * v1.R + dw2_dx * v2.R;
float dg_dx = dw0_dx * v0.G + dw1_dx * v1.G + dw2_dx * v2.G;
float db_dx = dw0_dx * v0.B + dw1_dx * v1.B + dw2_dx * v2.B;
float da_dx = dw0_dx * v0.A + dw1_dx * v1.A + dw2_dx * v2.A;
float du_dx = dw0_dx * v0.U + dw1_dx * v1.U + dw2_dx * v2.U;
float dv_dx = dw0_dx * v0.V + dw1_dx * v1.V + dw2_dx * v2.V;
float dr_dy = dw0_dy * v0.R + dw1_dy * v1.R + dw2_dy * v2.R;
float dg_dy = dw0_dy * v0.G + dw1_dy * v1.G + dw2_dy * v2.G;
float db_dy = dw0_dy * v0.B + dw1_dy * v1.B + dw2_dy * v2.B;
float da_dy = dw0_dy * v0.A + dw1_dy * v1.A + dw2_dy * v2.A;
float du_dy = dw0_dy * v0.U + dw1_dy * v1.U + dw2_dy * v2.U;
float dv_dy = dw0_dy * v0.V + dw1_dy * v1.V + dw2_dy * v2.V;
float start_x = (float)min_x + 0.5f;
float start_y = (float)min_y + 0.5f;
float e0_row = ImGui_ImplSDLSurface3_Edge(v1.X, v1.Y, v2.X, v2.Y, start_x, start_y) * sign;
float e1_row = ImGui_ImplSDLSurface3_Edge(v2.X, v2.Y, v0.X, v0.Y, start_x, start_y) * sign;
float e2_row = ImGui_ImplSDLSurface3_Edge(v0.X, v0.Y, v1.X, v1.Y, start_x, start_y) * sign;
float w0_row = e0_row * inv_area;
float w1_row = e1_row * inv_area;
float w2_row = e2_row * inv_area;
float r_row = w0_row * v0.R + w1_row * v1.R + w2_row * v2.R;
float g_row = w0_row * v0.G + w1_row * v1.G + w2_row * v2.G;
float b_row = w0_row * v0.B + w1_row * v1.B + w2_row * v2.B;
float a_row = w0_row * v0.A + w1_row * v1.A + w2_row * v2.A;
float u_row = w0_row * v0.U + w1_row * v1.U + w2_row * v2.U;
float v_row = w0_row * v0.V + w1_row * v1.V + w2_row * v2.V;
int texture_max_x = texture ? (texture->Width - 1) : 0;
int texture_max_y = texture ? (texture->Height - 1) : 0;
for (int y = min_y; y <= max_y; y++)
{
float e0 = e0_row;
float e1 = e1_row;
float e2 = e2_row;
float r = r_row;
float g = g_row;
float b = b_row;
float a = a_row;
float u = u_row;
float v = v_row;
Uint32* dst = (Uint32*)(target.Pixels + y * target.Pitch) + min_x;
for (int x = min_x; x <= max_x; x++)
{
if (e0 >= 0.0f && e1 >= 0.0f && e2 >= 0.0f)
{
Uint8 out_r = ImGui_ImplSDLSurface3_ClampByte(r);
Uint8 out_g = ImGui_ImplSDLSurface3_ClampByte(g);
Uint8 out_b = ImGui_ImplSDLSurface3_ClampByte(b);
Uint8 out_a = ImGui_ImplSDLSurface3_ClampByte(a);
if (texture != nullptr)
{
int tx = ImGui_ImplSDLSurface3_ClampInt((int)(u * (float)texture_max_x + 0.5f), 0, texture_max_x);
int ty = ImGui_ImplSDLSurface3_ClampInt((int)(v * (float)texture_max_y + 0.5f), 0, texture_max_y);
Uint8 tr, tg, tb, ta;
ImGui_ImplSDLSurface3_ReadPixelRGBA(*texture, tx, ty, &tr, &tg, &tb, &ta);
out_r = ImGui_ImplSDLSurface3_Mul255(out_r, tr);
out_g = ImGui_ImplSDLSurface3_Mul255(out_g, tg);
out_b = ImGui_ImplSDLSurface3_Mul255(out_b, tb);
out_a = ImGui_ImplSDLSurface3_Mul255(out_a, ta);
}
ImGui_ImplSDLSurface3_BlendPixelFast(target, dst, out_r, out_g, out_b, out_a);
}
dst++;
e0 += e0_dx;
e1 += e1_dx;
e2 += e2_dx;
r += dr_dx;
g += dg_dx;
b += db_dx;
a += da_dx;
u += du_dx;
v += dv_dx;
}
e0_row += e0_dy;
e1_row += e1_dy;
e2_row += e2_dy;
r_row += dr_dy;
g_row += dg_dy;
b_row += db_dy;
a_row += da_dy;
u_row += du_dy;
v_row += dv_dy;
}
}
static void ImGui_ImplSDLSurface3_RenderTriangleGeneric(const ImGui_ImplSDLSurface3_SurfaceInfo& target, const ImGui_ImplSDLSurface3_SurfaceInfo* texture, const ImGui_ImplSDLSurface3_RasterVertex& v0, const ImGui_ImplSDLSurface3_RasterVertex& v1, const ImGui_ImplSDLSurface3_RasterVertex& v2, int clip_min_x, int clip_min_y, int clip_max_x, int clip_max_y)
{
int min_x = std::max((int)std::floor(std::min(v0.X, std::min(v1.X, v2.X))), clip_min_x);
int min_y = std::max((int)std::floor(std::min(v0.Y, std::min(v1.Y, v2.Y))), clip_min_y);
int max_x = std::min((int)std::ceil(std::max(v0.X, std::max(v1.X, v2.X))) - 1, clip_max_x - 1);
int max_y = std::min((int)std::ceil(std::max(v0.Y, std::max(v1.Y, v2.Y))) - 1, clip_max_y - 1);
if (min_x > max_x || min_y > max_y)
return;
float area = ImGui_ImplSDLSurface3_Edge(v0.X, v0.Y, v1.X, v1.Y, v2.X, v2.Y);
if (area == 0.0f)
return;
float sign = (area < 0.0f) ? -1.0f : 1.0f;
area *= sign;
float e0_dx = (v1.Y - v2.Y) * sign;
float e0_dy = (v2.X - v1.X) * sign;
float e1_dx = (v2.Y - v0.Y) * sign;
float e1_dy = (v0.X - v2.X) * sign;
float e2_dx = (v0.Y - v1.Y) * sign;
float e2_dy = (v1.X - v0.X) * sign;
float inv_area = 1.0f / area;
float dw0_dx = e0_dx * inv_area;
float dw0_dy = e0_dy * inv_area;
float dw1_dx = e1_dx * inv_area;
float dw1_dy = e1_dy * inv_area;
float dw2_dx = e2_dx * inv_area;
float dw2_dy = e2_dy * inv_area;
float dr_dx = dw0_dx * v0.R + dw1_dx * v1.R + dw2_dx * v2.R;
float dg_dx = dw0_dx * v0.G + dw1_dx * v1.G + dw2_dx * v2.G;
float db_dx = dw0_dx * v0.B + dw1_dx * v1.B + dw2_dx * v2.B;
float da_dx = dw0_dx * v0.A + dw1_dx * v1.A + dw2_dx * v2.A;
float du_dx = dw0_dx * v0.U + dw1_dx * v1.U + dw2_dx * v2.U;
float dv_dx = dw0_dx * v0.V + dw1_dx * v1.V + dw2_dx * v2.V;
float dr_dy = dw0_dy * v0.R + dw1_dy * v1.R + dw2_dy * v2.R;
float dg_dy = dw0_dy * v0.G + dw1_dy * v1.G + dw2_dy * v2.G;
float db_dy = dw0_dy * v0.B + dw1_dy * v1.B + dw2_dy * v2.B;
float da_dy = dw0_dy * v0.A + dw1_dy * v1.A + dw2_dy * v2.A;
float du_dy = dw0_dy * v0.U + dw1_dy * v1.U + dw2_dy * v2.U;
float dv_dy = dw0_dy * v0.V + dw1_dy * v1.V + dw2_dy * v2.V;
float start_x = (float)min_x + 0.5f;
float start_y = (float)min_y + 0.5f;
float e0_row = ImGui_ImplSDLSurface3_Edge(v1.X, v1.Y, v2.X, v2.Y, start_x, start_y) * sign;
float e1_row = ImGui_ImplSDLSurface3_Edge(v2.X, v2.Y, v0.X, v0.Y, start_x, start_y) * sign;
float e2_row = ImGui_ImplSDLSurface3_Edge(v0.X, v0.Y, v1.X, v1.Y, start_x, start_y) * sign;
float w0_row = e0_row * inv_area;
float w1_row = e1_row * inv_area;
float w2_row = e2_row * inv_area;
float r_row = w0_row * v0.R + w1_row * v1.R + w2_row * v2.R;
float g_row = w0_row * v0.G + w1_row * v1.G + w2_row * v2.G;
float b_row = w0_row * v0.B + w1_row * v1.B + w2_row * v2.B;
float a_row = w0_row * v0.A + w1_row * v1.A + w2_row * v2.A;
float u_row = w0_row * v0.U + w1_row * v1.U + w2_row * v2.U;
float v_row = w0_row * v0.V + w1_row * v1.V + w2_row * v2.V;
int texture_max_x = texture ? (texture->Width - 1) : 0;
int texture_max_y = texture ? (texture->Height - 1) : 0;
for (int y = min_y; y <= max_y; y++)
{
float e0 = e0_row;
float e1 = e1_row;
float e2 = e2_row;
float r = r_row;
float g = g_row;
float b = b_row;
float a = a_row;
float u = u_row;
float v = v_row;
for (int x = min_x; x <= max_x; x++)
{
if (e0 >= 0.0f && e1 >= 0.0f && e2 >= 0.0f)
{
Uint8 out_r = ImGui_ImplSDLSurface3_ClampByte(r);
Uint8 out_g = ImGui_ImplSDLSurface3_ClampByte(g);
Uint8 out_b = ImGui_ImplSDLSurface3_ClampByte(b);
Uint8 out_a = ImGui_ImplSDLSurface3_ClampByte(a);
if (texture != nullptr)
{
int tx = ImGui_ImplSDLSurface3_ClampInt((int)(u * (float)texture_max_x + 0.5f), 0, texture_max_x);
int ty = ImGui_ImplSDLSurface3_ClampInt((int)(v * (float)texture_max_y + 0.5f), 0, texture_max_y);
Uint8 tr, tg, tb, ta;
ImGui_ImplSDLSurface3_ReadPixelRGBA(*texture, tx, ty, &tr, &tg, &tb, &ta);
out_r = ImGui_ImplSDLSurface3_Mul255(out_r, tr);
out_g = ImGui_ImplSDLSurface3_Mul255(out_g, tg);
out_b = ImGui_ImplSDLSurface3_Mul255(out_b, tb);
out_a = ImGui_ImplSDLSurface3_Mul255(out_a, ta);
}
ImGui_ImplSDLSurface3_BlendPixelGeneric(target, x, y, out_r, out_g, out_b, out_a);
}
e0 += e0_dx;
e1 += e1_dx;
e2 += e2_dx;
r += dr_dx;
g += dg_dx;
b += db_dx;
a += da_dx;
u += du_dx;
v += dv_dx;
}
e0_row += e0_dy;
e1_row += e1_dy;
e2_row += e2_dy;
r_row += dr_dy;
g_row += dg_dy;
b_row += db_dy;
a_row += da_dy;
u_row += du_dy;
v_row += dv_dy;
}
}
SDL_Surface* ImGui_ImplSDLSurface3_CreateFontAtlasSurface()
{
ImGuiIO& io = ImGui::GetIO();
unsigned char* pixels = nullptr;
int width = 0;
int height = 0;
io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height);
if (pixels == nullptr || width <= 0 || height <= 0)
return nullptr;
SDL_Surface* surface = SDL_CreateSurface(width, height, SDL_PIXELFORMAT_RGBA32);
if (surface == nullptr)
return nullptr;
if (SDL_MUSTLOCK(surface) && !SDL_LockSurface(surface))
{
SDL_DestroySurface(surface);
return nullptr;
}
for (int y = 0; y < height; y++)
memcpy((Uint8*)surface->pixels + y * surface->pitch, pixels + (size_t)y * (size_t)width * 4, (size_t)width * 4);
if (SDL_MUSTLOCK(surface))
SDL_UnlockSurface(surface);
SDL_SetSurfaceBlendMode(surface, SDL_BLENDMODE_NONE);
return surface;
}
bool ImGui_ImplSDLSurface3_Init(SDL_Surface* surface)
{
if (surface == nullptr)
return false;
ImGuiIO& io = ImGui::GetIO();
IMGUI_CHECKVERSION();
IM_ASSERT(io.BackendRendererUserData == nullptr && "Already initialized a renderer backend!");
ImGui_ImplSDLSurface3_Data* bd = IM_NEW(ImGui_ImplSDLSurface3_Data)();
io.BackendRendererUserData = (void*)bd;
io.BackendRendererName = "imgui_impl_sdlsurface3";
bd->TargetSurface = surface;
ImGui_ImplSDLSurface3_InitSurfaceInfo(&bd->TargetInfo, surface);
bd->FontSurface = ImGui_ImplSDLSurface3_CreateFontAtlasSurface();
if (bd->FontSurface != nullptr)
io.Fonts->TexID = (ImTextureID)bd->FontSurface;
return true;
}
void ImGui_ImplSDLSurface3_Shutdown()
{
ImGui_ImplSDLSurface3_Data* bd = ImGui_ImplSDLSurface3_GetBackendData();
IM_ASSERT(bd != nullptr && "No renderer backend to shutdown, or already shutdown?");
ImGuiIO& io = ImGui::GetIO();
ImGuiPlatformIO& platform_io = ImGui::GetPlatformIO();
io.Fonts->TexID = nullptr;
io.BackendRendererName = nullptr;
io.BackendRendererUserData = nullptr;
platform_io.ClearRendererHandlers();
if (bd->FontSurface != nullptr)
SDL_DestroySurface(bd->FontSurface);
IM_DELETE(bd);
}
void ImGui_ImplSDLSurface3_NewFrame()
{
ImGui_ImplSDLSurface3_Data* bd = ImGui_ImplSDLSurface3_GetBackendData();
IM_ASSERT(bd != nullptr && "Context or backend not initialized! Did you call ImGui_ImplSDLSurface3_Init()?");
IM_UNUSED(bd);
}
void ImGui_ImplSDLSurface3_RenderDrawData(ImDrawData* draw_data)
{
ImGui_ImplSDLSurface3_Data* bd = ImGui_ImplSDLSurface3_GetBackendData();
if (bd == nullptr || draw_data == nullptr || bd->TargetSurface == nullptr)
return;
if (SDL_MUSTLOCK(bd->TargetSurface) && !SDL_LockSurface(bd->TargetSurface))
return;
ImGui_ImplSDLSurface3_InitSurfaceInfo(&bd->TargetInfo, bd->TargetSurface);
if (bd->TargetInfo.Width <= 0 || bd->TargetInfo.Height <= 0)
{
if (SDL_MUSTLOCK(bd->TargetSurface))
SDL_UnlockSurface(bd->TargetSurface);
return;
}
const ImVec2 clip_off = draw_data->DisplayPos;
const ImVec2 clip_scale = draw_data->FramebufferScale;
for (int n = 0; n < draw_data->CmdListsCount; n++)
{
const ImDrawList* draw_list = draw_data->CmdLists[n];
const ImDrawVert* vtx_buffer = draw_list->VtxBuffer.Data;
const ImDrawIdx* idx_buffer = draw_list->IdxBuffer.Data;
for (int cmd_i = 0; cmd_i < draw_list->CmdBuffer.Size; cmd_i++)
{
const ImDrawCmd* pcmd = &draw_list->CmdBuffer[cmd_i];
if (pcmd->UserCallback != nullptr)
{
if (pcmd->UserCallback != ImDrawCallback_ResetRenderState)
pcmd->UserCallback(draw_list, pcmd);
continue;
}
if (pcmd->ElemCount == 0)
continue;
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)bd->TargetInfo.Width) clip_max.x = (float)bd->TargetInfo.Width;
if (clip_max.y > (float)bd->TargetInfo.Height) clip_max.y = (float)bd->TargetInfo.Height;
if (clip_max.x <= clip_min.x || clip_max.y <= clip_min.y)
continue;
int clip_min_x = (int)clip_min.x;
int clip_min_y = (int)clip_min.y;
int clip_max_x = (int)clip_max.x;
int clip_max_y = (int)clip_max.y;
SDL_Surface* texture_surface = (SDL_Surface*)pcmd->GetTexID();
ImGui_ImplSDLSurface3_SurfaceInfo texture_info;
ImGui_ImplSDLSurface3_SurfaceInfo* texture_ptr = nullptr;
bool texture_locked = false;
if (texture_surface != nullptr)
{
if (SDL_MUSTLOCK(texture_surface))
{
if (!SDL_LockSurface(texture_surface))
texture_surface = nullptr;
else
texture_locked = true;
}
if (texture_surface != nullptr)
{
ImGui_ImplSDLSurface3_InitSurfaceInfo(&texture_info, texture_surface);
if (texture_info.Width > 0 && texture_info.Height > 0)
texture_ptr = &texture_info;
}
}
for (unsigned int idx = 0; idx + 2 < (unsigned int)pcmd->ElemCount; idx += 3)
{
ImDrawIdx idx0 = idx_buffer[pcmd->IdxOffset + idx + 0];
ImDrawIdx idx1 = idx_buffer[pcmd->IdxOffset + idx + 1];
ImDrawIdx idx2 = idx_buffer[pcmd->IdxOffset + idx + 2];
ImGui_ImplSDLSurface3_RasterVertex v0;
ImGui_ImplSDLSurface3_RasterVertex v1;
ImGui_ImplSDLSurface3_RasterVertex v2;
ImGui_ImplSDLSurface3_SetupRasterVertex(&v0, vtx_buffer[pcmd->VtxOffset + idx0], clip_off, clip_scale);
ImGui_ImplSDLSurface3_SetupRasterVertex(&v1, vtx_buffer[pcmd->VtxOffset + idx1], clip_off, clip_scale);
ImGui_ImplSDLSurface3_SetupRasterVertex(&v2, vtx_buffer[pcmd->VtxOffset + idx2], clip_off, clip_scale);
if (bd->TargetInfo.IsFast)
ImGui_ImplSDLSurface3_RenderTriangleFast(bd->TargetInfo, texture_ptr, v0, v1, v2, clip_min_x, clip_min_y, clip_max_x, clip_max_y);
else
ImGui_ImplSDLSurface3_RenderTriangleGeneric(bd->TargetInfo, texture_ptr, v0, v1, v2, clip_min_x, clip_min_y, clip_max_x, clip_max_y);
}
if (texture_locked)
SDL_UnlockSurface(texture_surface);
}
}
if (SDL_MUSTLOCK(bd->TargetSurface))
SDL_UnlockSurface(bd->TargetSurface);
}
#endif
backends/imgui_impl_sdlsurface3.h
+11
View File
@@ -0,0 +1,11 @@
#pragma once
#include "imgui.h"
#include <SDL3/SDL.h>
IMGUI_API bool ImGui_ImplSDLSurface3_Init(SDL_Surface* surface);
IMGUI_API void ImGui_ImplSDLSurface3_Shutdown();
IMGUI_API void ImGui_ImplSDLSurface3_NewFrame();
IMGUI_API void ImGui_ImplSDLSurface3_RenderDrawData(ImDrawData* draw_data);
IMGUI_API SDL_Surface* ImGui_ImplSDLSurface3_CreateFontAtlasSurface();