ref: 7e926451def20e69909b199adba48e7dceee608d
dir: /src/Backends/Rendering/SDLSurface.cpp/
#include "../Rendering.h"
#include <stddef.h>
#include <stdlib.h>
#include "SDL.h"
#include "../../WindowsWrapper.h"
#include "../../Font.h"
typedef struct Backend_Surface
{
SDL_Surface *sdl_surface;
} Backend_Surface;
typedef struct Backend_Glyph
{
SDL_Surface *sdl_surface;
} Backend_Glyph;
static SDL_Window *window;
static SDL_Surface *window_surface;
static Backend_Surface framebuffer;
static void RectToSDLRect(const RECT *rect, SDL_Rect *sdl_rect)
{
sdl_rect->x = (int)rect->left;
sdl_rect->y = (int)rect->top;
sdl_rect->w = (int)(rect->right - rect->left);
sdl_rect->h = (int)(rect->bottom - rect->top);
if (sdl_rect->w < 0)
sdl_rect->w = 0;
if (sdl_rect->h < 0)
sdl_rect->h = 0;
}
static unsigned char GammaCorrect(unsigned char value)
{
/*
Generated with...
for (unsigned int i = 0; i < 0x100; ++i)
lookup[i] = pow(i / 255.0, 1.0 / 1.8) * 255.0;
*/
const unsigned char lookup[0x100] = {
0x00, 0x0B, 0x11, 0x15, 0x19, 0x1C, 0x1F, 0x22, 0x25, 0x27, 0x2A, 0x2C, 0x2E, 0x30, 0x32, 0x34,
0x36, 0x38, 0x3A, 0x3C, 0x3D, 0x3F, 0x41, 0x43, 0x44, 0x46, 0x47, 0x49, 0x4A, 0x4C, 0x4D, 0x4F,
0x50, 0x51, 0x53, 0x54, 0x55, 0x57, 0x58, 0x59, 0x5B, 0x5C, 0x5D, 0x5E, 0x60, 0x61, 0x62, 0x63,
0x64, 0x65, 0x67, 0x68, 0x69, 0x6A, 0x6B, 0x6C, 0x6D, 0x6E, 0x70, 0x71, 0x72, 0x73, 0x74, 0x75,
0x76, 0x77, 0x78, 0x79, 0x7A, 0x7B, 0x7C, 0x7D, 0x7E, 0x7F, 0x80, 0x81, 0x82, 0x83, 0x84, 0x84,
0x85, 0x86, 0x87, 0x88, 0x89, 0x8A, 0x8B, 0x8C, 0x8D, 0x8E, 0x8E, 0x8F, 0x90, 0x91, 0x92, 0x93,
0x94, 0x95, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9A, 0x9A, 0x9B, 0x9C, 0x9D, 0x9E, 0x9F, 0x9F, 0xA0,
0xA1, 0xA2, 0xA3, 0xA3, 0xA4, 0xA5, 0xA6, 0xA6, 0xA7, 0xA8, 0xA9, 0xAA, 0xAA, 0xAB, 0xAC, 0xAD,
0xAD, 0xAE, 0xAF, 0xB0, 0xB0, 0xB1, 0xB2, 0xB3, 0xB3, 0xB4, 0xB5, 0xB6, 0xB6, 0xB7, 0xB8, 0xB8,
0xB9, 0xBA, 0xBB, 0xBB, 0xBC, 0xBD, 0xBD, 0xBE, 0xBF, 0xBF, 0xC0, 0xC1, 0xC2, 0xC2, 0xC3, 0xC4,
0xC4, 0xC5, 0xC6, 0xC6, 0xC7, 0xC8, 0xC8, 0xC9, 0xCA, 0xCA, 0xCB, 0xCC, 0xCC, 0xCD, 0xCE, 0xCE,
0xCF, 0xD0, 0xD0, 0xD1, 0xD2, 0xD2, 0xD3, 0xD4, 0xD4, 0xD5, 0xD6, 0xD6, 0xD7, 0xD7, 0xD8, 0xD9,
0xD9, 0xDA, 0xDB, 0xDB, 0xDC, 0xDC, 0xDD, 0xDE, 0xDE, 0xDF, 0xE0, 0xE0, 0xE1, 0xE1, 0xE2, 0xE3,
0xE3, 0xE4, 0xE4, 0xE5, 0xE6, 0xE6, 0xE7, 0xE7, 0xE8, 0xE9, 0xE9, 0xEA, 0xEA, 0xEB, 0xEC, 0xEC,
0xED, 0xED, 0xEE, 0xEF, 0xEF, 0xF0, 0xF0, 0xF1, 0xF1, 0xF2, 0xF3, 0xF3, 0xF4, 0xF4, 0xF5, 0xF5,
0xF6, 0xF7, 0xF7, 0xF8, 0xF8, 0xF9, 0xF9, 0xFA, 0xFB, 0xFB, 0xFC, 0xFC, 0xFD, 0xFD, 0xFE, 0xFF
}
return lookup[value];
}
SDL_Window* Backend_CreateWindow(const char *title, int width, int height)
{
return SDL_CreateWindow(title, SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, width, height, 0);
}
BOOL Backend_Init(SDL_Window *p_window)
{
window = p_window;
window_surface = SDL_GetWindowSurface(window);
framebuffer.sdl_surface = SDL_CreateRGBSurfaceWithFormat(0, window_surface->w, window_surface->h, 0, SDL_PIXELFORMAT_RGB24);
if (framebuffer.sdl_surface == NULL)
return FALSE;
return TRUE;
}
void Backend_Deinit(void)
{
SDL_FreeSurface(framebuffer.sdl_surface);
}
void Backend_DrawScreen(void)
{
SDL_BlitSurface(framebuffer.sdl_surface, NULL, window_surface, NULL);
SDL_UpdateWindowSurface(window);
}
Backend_Surface* Backend_CreateSurface(unsigned int width, unsigned int height)
{
Backend_Surface *surface = (Backend_Surface*)malloc(sizeof(Backend_Surface));
if (surface == NULL)
return NULL;
surface->sdl_surface = SDL_CreateRGBSurfaceWithFormat(0, width, height, 0, SDL_PIXELFORMAT_RGB24);
if (surface->sdl_surface == NULL)
{
free(surface);
return NULL;
}
return surface;
}
void Backend_FreeSurface(Backend_Surface *surface)
{
if (surface == NULL)
return;
SDL_FreeSurface(surface->sdl_surface);
free(surface);
}
unsigned char* Backend_Lock(Backend_Surface *surface, unsigned int *pitch)
{
if (surface == NULL)
return NULL;
*pitch = surface->sdl_surface->pitch;
return (unsigned char*)surface->sdl_surface->pixels;
}
void Backend_Unlock(Backend_Surface *surface)
{
(void)surface;
}
void Backend_Blit(Backend_Surface *source_surface, const RECT *rect, Backend_Surface *destination_surface, long x, long y, BOOL colour_key)
{
if (source_surface == NULL || destination_surface == NULL)
return;
SDL_Rect source_rect;
RectToSDLRect(rect, &source_rect);
SDL_Rect destination_rect;
destination_rect.x = x;
destination_rect.y = y;
destination_rect.w = source_rect.w;
destination_rect.h = source_rect.h;
SDL_SetColorKey(source_surface->sdl_surface, colour_key ? SDL_TRUE : SDL_FALSE, SDL_MapRGB(source_surface->sdl_surface->format, 0, 0, 0)); // Assumes the colour key will always be #000000 (black)
SDL_BlitSurface(source_surface->sdl_surface, &source_rect, destination_surface->sdl_surface, &destination_rect);
}
void Backend_BlitToScreen(Backend_Surface *source_surface, const RECT *rect, long x, long y, BOOL colour_key)
{
Backend_Blit(source_surface, rect, &framebuffer, x, y, colour_key);
}
void Backend_ColourFill(Backend_Surface *surface, const RECT *rect, unsigned char red, unsigned char green, unsigned char blue)
{
if (surface == NULL)
return;
SDL_Rect destination_rect;
RectToSDLRect(rect, &destination_rect);
SDL_FillRect(surface->sdl_surface, &destination_rect, SDL_MapRGB(surface->sdl_surface->format, red, green, blue));
}
void Backend_ColourFillToScreen(const RECT *rect, unsigned char red, unsigned char green, unsigned char blue)
{
Backend_ColourFill(&framebuffer, rect, red, green, blue);
}
void Backend_ScreenToSurface(Backend_Surface *surface, const RECT *rect)
{
Backend_Blit(&framebuffer, rect, surface, rect->left, rect->top, FALSE);
}
BOOL Backend_SupportsSubpixelGlyph(void)
{
return FALSE; // SDL_Surfaces don't have per-component alpha
}
Backend_Glyph* Backend_LoadGlyph(const unsigned char *pixels, unsigned int width, unsigned int height, int pitch, unsigned short total_greys, unsigned char pixel_mode)
{
Backend_Glyph *glyph = (Backend_Glyph*)malloc(sizeof(Backend_Glyph));
if (glyph == NULL)
return NULL;
glyph->sdl_surface = SDL_CreateRGBSurfaceWithFormat(0, width, height, 0, SDL_PIXELFORMAT_RGBA32);
if (glyph->sdl_surface == NULL)
{
free(glyph);
return NULL;
}
switch (pixel_mode)
{
// FONT_PIXEL_MODE_LCD is unsupported
case FONT_PIXEL_MODE_GRAY:
for (unsigned int y = 0; y < height; ++y)
{
const unsigned char *source_pointer = pixels + y * pitch;
unsigned char *destination_pointer = (unsigned char*)glyph->sdl_surface->pixels + y * glyph->sdl_surface->pitch;
for (unsigned int x = 0; x < width; ++x)
{
*destination_pointer++ = 0xFF;
*destination_pointer++ = 0xFF;
*destination_pointer++ = 0xFF;
*destination_pointer++ = GammaCorrect((*source_pointer++ * 0xFF) / (total_greys - 1));
}
}
break;
case FONT_PIXEL_MODE_MONO:
for (unsigned int y = 0; y < height; ++y)
{
const unsigned char *source_pointer = pixels + y * pitch;
unsigned char *destination_pointer = (unsigned char*)glyph->sdl_surface->pixels + y * glyph->sdl_surface->pitch;
for (unsigned int x = 0; x < width; ++x)
{
*destination_pointer++ = 0xFF;
*destination_pointer++ = 0xFF;
*destination_pointer++ = 0xFF;
*destination_pointer++ = *source_pointer++ ? 0xFF : 0;
}
}
break;
}
return glyph;
}
void Backend_UnloadGlyph(Backend_Glyph *glyph)
{
if (glyph == NULL)
return;
SDL_FreeSurface(glyph->sdl_surface);
free(glyph);
}
void Backend_DrawGlyph(Backend_Surface *surface, Backend_Glyph *glyph, long x, long y, const unsigned char *colours)
{
if (glyph == NULL || surface == NULL)
return;
SDL_Rect rect;
rect.x = x;
rect.y = y;
rect.w = glyph->sdl_surface->w;
rect.h = glyph->sdl_surface->h;
SDL_SetSurfaceColorMod(glyph->sdl_surface, colours[0], colours[1], colours[2]);
SDL_BlitSurface(glyph->sdl_surface, NULL, surface->sdl_surface, &rect);
}
void Backend_DrawGlyphToScreen(Backend_Glyph *glyph, long x, long y, const unsigned char *colours)
{
Backend_DrawGlyph(&framebuffer, glyph, x, y, colours);
}
void Backend_HandleDeviceLoss(void)
{
// No problem for us
}
void Backend_HandleWindowResize(void)
{
// https://wiki.libsdl.org/SDL_GetWindowSurface
// We need to fetch a new surface pointer
window_surface = SDL_GetWindowSurface(window);
}