ref: 71199c7693133816999542cd1152d57c7fd1327d
dir: /src/Backends/Rendering/SDLTexture.cpp/
#include "../Rendering.h"
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <string>
#include "SDL.h"
#define SPRITEBATCH_IMPLEMENTATION
#include "../../../external/cute_spritebatch.h"
#include "../../WindowsWrapper.h"
#include "../Misc.h"
#include "../Shared/SDL2.h"
typedef struct RenderBackend_Surface
{
SDL_Texture *texture;
unsigned char *pixels;
unsigned int width;
unsigned int height;
bool lost;
struct RenderBackend_Surface *next;
struct RenderBackend_Surface *prev;
} RenderBackend_Surface;
typedef struct RenderBackend_Glyph
{
unsigned char *pixels;
unsigned int width;
unsigned int height;
} RenderBackend_Glyph;
SDL_Window *window;
static SDL_Renderer *renderer;
static RenderBackend_Surface framebuffer;
static RenderBackend_Surface *surface_list_head;
static unsigned char glyph_colour_channels[3];
static spritebatch_t glyph_batcher;
static void RectToSDLRect(const RenderBackend_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;
}
// Blit the glyphs in the batch
static void GlyphBatch_Draw(spritebatch_sprite_t *sprites, int count, int texture_w, int texture_h, void *udata)
{
(void)udata;
SDL_Texture *texture_atlas = (SDL_Texture*)sprites[0].texture_id;
// The SDL_Texture side of things uses alpha, not a colour-key, so the bug where the font is blended
// with the colour key doesn't occur.
if (SDL_SetTextureColorMod(texture_atlas, glyph_colour_channels[0], glyph_colour_channels[1], glyph_colour_channels[2]) < 0)
Backend_PrintError("Couldn't set additional color value: %s", SDL_GetError());
if (SDL_SetTextureBlendMode(texture_atlas, SDL_BLENDMODE_BLEND) < 0)
Backend_PrintError("Couldn't set texture blend mode: %s", SDL_GetError());
for (int i = 0; i < count; ++i)
{
RenderBackend_Glyph *glyph = (RenderBackend_Glyph*)sprites[i].image_id;
SDL_Rect source_rect = {(int)(texture_w * sprites[i].minx), (int)(texture_h * sprites[i].maxy), (int)glyph->width, (int)glyph->height};
SDL_Rect destination_rect = {(int)sprites[i].x, (int)sprites[i].y, (int)glyph->width, (int)glyph->height};
if (SDL_RenderCopy(renderer, texture_atlas, &source_rect, &destination_rect) < 0)
Backend_PrintError("Couldn't copy glyph texture portion to renderer: %s", SDL_GetError());
}
}
// Upload the glyph's pixels
static void GlyphBatch_GetPixels(SPRITEBATCH_U64 image_id, void *buffer, int bytes_to_fill, void *udata)
{
(void)udata;
RenderBackend_Glyph *glyph = (RenderBackend_Glyph*)image_id;
memcpy(buffer, glyph->pixels, bytes_to_fill);
}
// Create a texture atlas, and upload pixels to it
static SPRITEBATCH_U64 GlyphBatch_CreateTexture(void *pixels, int w, int h, void *udata)
{
(void)udata;
SDL_Texture *texture = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_RGBA32, SDL_TEXTUREACCESS_STATIC, w, h);
if (texture == NULL)
Backend_PrintError("Couldn't create texture for renderer: %s", SDL_GetError());
if (SDL_UpdateTexture(texture, NULL, pixels, w * 4) < 0)
Backend_PrintError("Couldn't update texture: %s", SDL_GetError());
return (SPRITEBATCH_U64)texture;
}
// Destroy texture atlas
static void GlyphBatch_DestroyTexture(SPRITEBATCH_U64 texture_id, void *udata)
{
(void)udata;
SDL_DestroyTexture((SDL_Texture*)texture_id);
}
RenderBackend_Surface* RenderBackend_Init(const char *window_title, int screen_width, int screen_height, bool fullscreen)
{
Backend_PrintInfo("Available SDL render drivers:");
for (int i = 0; i < SDL_GetNumRenderDrivers(); ++i)
{
SDL_RendererInfo info;
if (SDL_GetRenderDriverInfo(i, &info) < 0)
Backend_PrintError("Couldn't get render driver information: %s", SDL_GetError());
else
Backend_PrintInfo("%s", info.name);
}
window = SDL_CreateWindow(window_title, SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, screen_width, screen_height, 0);
if (window != NULL)
{
if (fullscreen)
if (SDL_SetWindowFullscreen(window, SDL_WINDOW_FULLSCREEN) < 0)
Backend_PrintError("Couldn't set window to fullscreen: %s", SDL_GetError());
#if SDL_VERSION_ATLEAST(2,0,10)
SDL_SetHint(SDL_HINT_RENDER_BATCHING, "1"); // We never interfere with the renderer, so don't let SDL implicitly disable batching
#endif
renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED | SDL_RENDERER_TARGETTEXTURE);
if (renderer != NULL)
{
SDL_RendererInfo info;
if (SDL_GetRendererInfo(renderer, &info) < 0)
Backend_PrintError("Couldn't get selected render driver information: %s", SDL_GetError());
else
Backend_PrintInfo("Selected SDL render driver: %s", info.name);
framebuffer.texture = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_RGBA32, SDL_TEXTUREACCESS_TARGET, screen_width, screen_height);
if (framebuffer.texture != NULL)
{
framebuffer.width = screen_width;
framebuffer.height = screen_height;
// Set-up glyph-batcher
spritebatch_config_t config;
spritebatch_set_default_config(&config);
config.pixel_stride = 4;
config.atlas_width_in_pixels = 256;
config.atlas_height_in_pixels = 256;
config.lonely_buffer_count_till_flush = 4; // Start making atlases immediately
config.batch_callback = GlyphBatch_Draw;
config.get_pixels_callback = GlyphBatch_GetPixels;
config.generate_texture_callback = GlyphBatch_CreateTexture;
config.delete_texture_callback = GlyphBatch_DestroyTexture;
if (spritebatch_init(&glyph_batcher, &config, NULL) == 0)
{
Backend_PostWindowCreation();
return &framebuffer;
}
else
{
Backend_ShowMessageBox("Fatal error (SDLTexture rendering backend)", "Failed to initialize spritebatch");
}
}
else
{
std::string error_message = std::string("Could not create framebuffer: ") + SDL_GetError();
Backend_ShowMessageBox("Fatal error (SDLTexture rendering backend)", error_message.c_str());
}
SDL_DestroyRenderer(renderer);
}
else
{
std::string error_message = std::string("Could not create renderer: ") + SDL_GetError();
Backend_ShowMessageBox("Fatal error (SDLTexture rendering backend)", error_message.c_str());
}
SDL_DestroyWindow(window);
}
else
{
std::string error_message = std::string("Could not create window: ") + SDL_GetError();
Backend_ShowMessageBox("Fatal error (SDLTexture rendering backend)", error_message.c_str());
}
return NULL;
}
void RenderBackend_Deinit(void)
{
spritebatch_term(&glyph_batcher);
SDL_DestroyTexture(framebuffer.texture);
SDL_DestroyRenderer(renderer);
SDL_DestroyWindow(window);
}
void RenderBackend_DrawScreen(void)
{
spritebatch_tick(&glyph_batcher);
if (SDL_SetRenderTarget(renderer, NULL) < 0)
Backend_PrintError("Couldn't set default render target as the current rendering target: %s", SDL_GetError());
if (SDL_RenderCopy(renderer, framebuffer.texture, NULL, NULL) < 0)
Backend_PrintError("Failed to copy framebuffer texture to default render target: %s", SDL_GetError());
SDL_RenderPresent(renderer);
}
RenderBackend_Surface* RenderBackend_CreateSurface(unsigned int width, unsigned int height, bool render_target)
{
RenderBackend_Surface *surface = (RenderBackend_Surface*)malloc(sizeof(RenderBackend_Surface));
if (surface == NULL)
return NULL;
surface->texture = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_RGBA32, render_target ? SDL_TEXTUREACCESS_TARGET : 0, width, height);
if (surface->texture == NULL)
{
free(surface);
return NULL;
}
surface->width = width;
surface->height = height;
surface->lost = false;
// Add to linked-list
surface->prev = NULL;
surface->next = surface_list_head;
surface_list_head = surface;
if (surface->next != NULL)
surface->next->prev = surface;
return surface;
}
void RenderBackend_FreeSurface(RenderBackend_Surface *surface)
{
if (surface == NULL)
return;
// Remove from linked list
if (surface->next != NULL)
surface->next->prev = surface->prev;
if (surface->prev != NULL)
surface->prev->next = surface->next;
SDL_DestroyTexture(surface->texture);
free(surface);
}
bool RenderBackend_IsSurfaceLost(RenderBackend_Surface *surface)
{
return surface->lost;
}
void RenderBackend_RestoreSurface(RenderBackend_Surface *surface)
{
surface->lost = false;
}
unsigned char* RenderBackend_LockSurface(RenderBackend_Surface *surface, unsigned int *pitch, unsigned int width, unsigned int height)
{
if (surface == NULL)
return NULL;
*pitch = width * 3;
surface->pixels = (unsigned char*)malloc(width * height * 3);
return surface->pixels;
}
void RenderBackend_UnlockSurface(RenderBackend_Surface *surface, unsigned int width, unsigned int height)
{
if (surface == NULL)
return;
unsigned char *buffer = (unsigned char*)malloc(width * height * 4);
if (buffer == NULL)
{
Backend_PrintError("Couldn't allocate memory for surface buffer: %s", SDL_GetError());
return;
}
const unsigned char *src_pixel = surface->pixels;
// Convert the SDL_Surface's colour-keyed pixels to RGBA32
for (unsigned int y = 0; y < height; ++y)
{
unsigned char *buffer_pointer = &buffer[y * width * 4];
for (unsigned int x = 0; x < width; ++x)
{
*buffer_pointer++ = src_pixel[0];
*buffer_pointer++ = src_pixel[1];
*buffer_pointer++ = src_pixel[2];
if (src_pixel[0] == 0 && src_pixel[1] == 0 && src_pixel[2] == 0) // Assumes the colour key will always be #000000 (black)
*buffer_pointer++ = 0;
else
*buffer_pointer++ = 0xFF;
src_pixel += 3;
}
}
free(surface->pixels);
SDL_Rect rect = {0, 0, (int)width, (int)height};
if (SDL_UpdateTexture(surface->texture, &rect, buffer, width * 4) < 0)
Backend_PrintError("Couldn't update part of texture: %s", SDL_GetError());
free(buffer);
}
void RenderBackend_Blit(RenderBackend_Surface *source_surface, const RenderBackend_Rect *rect, RenderBackend_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 = {(int)x, (int)y, source_rect.w, source_rect.h};
// Blit the texture
if (SDL_SetTextureBlendMode(source_surface->texture, colour_key ? SDL_BLENDMODE_BLEND : SDL_BLENDMODE_NONE) < 0)
Backend_PrintError("Couldn't set texture blend mode: %s", SDL_GetError());
if (SDL_SetRenderTarget(renderer, destination_surface->texture) < 0)
Backend_PrintError("Couldn't set current rendering target: %s", SDL_GetError());
if (SDL_RenderCopy(renderer, source_surface->texture, &source_rect, &destination_rect) < 0)
Backend_PrintError("Couldn't copy part of texture to rendering target: %s", SDL_GetError());
}
void RenderBackend_ColourFill(RenderBackend_Surface *surface, const RenderBackend_Rect *rect, unsigned char red, unsigned char green, unsigned char blue)
{
if (surface == NULL)
return;
SDL_Rect sdl_rect;
RectToSDLRect(rect, &sdl_rect);
Uint8 alpha = SDL_ALPHA_OPAQUE;
// Check colour-key
if (red == 0 && green == 0 && blue == 0)
alpha = 0;
if (SDL_SetRenderDrawColor(renderer, red, green, blue, alpha) < 0)
Backend_PrintError("Couldn't set color for drawing operations: %s", SDL_GetError());
// Draw colour
if (SDL_SetRenderTarget(renderer, surface->texture) < 0)
Backend_PrintError("Couldn't set texture current rendering target: %s", SDL_GetError());
if (SDL_SetRenderDrawBlendMode(renderer, SDL_BLENDMODE_NONE) < 0)
Backend_PrintError("Couldn't disable blending for drawing operations: %s", SDL_GetError());
if (SDL_RenderFillRect(renderer, &sdl_rect) < 0)
Backend_PrintError("Couldn't fill rectangle on current rendering target: %s", SDL_GetError());
if (SDL_SetRenderDrawBlendMode(renderer, SDL_BLENDMODE_BLEND) < 0)
Backend_PrintError("Couldn't enable alpha blending for drawing operations: %s", SDL_GetError());
}
RenderBackend_Glyph* RenderBackend_LoadGlyph(const unsigned char *pixels, unsigned int width, unsigned int height, int pitch)
{
RenderBackend_Glyph *glyph = (RenderBackend_Glyph*)malloc(sizeof(RenderBackend_Glyph));
if (glyph == NULL)
return NULL;
glyph->pixels = (unsigned char*)malloc(width * height * 4);
if (glyph->pixels == NULL)
{
free(glyph);
return NULL;
}
unsigned char *destination_pointer = glyph->pixels;
for (unsigned int y = 0; y < height; ++y)
{
const unsigned char *source_pointer = pixels + y * pitch;
for (unsigned int x = 0; x < width; ++x)
{
*destination_pointer++ = 0xFF;
*destination_pointer++ = 0xFF;
*destination_pointer++ = 0xFF;
*destination_pointer++ = *source_pointer++;
}
}
glyph->width = width;
glyph->height = height;
return glyph;
}
void RenderBackend_UnloadGlyph(RenderBackend_Glyph *glyph)
{
if (glyph == NULL)
return;
free(glyph->pixels);
free(glyph);
}
void RenderBackend_PrepareToDrawGlyphs(RenderBackend_Surface *destination_surface, const unsigned char *colour_channels)
{
if (destination_surface == NULL)
return;
if (SDL_SetRenderTarget(renderer, destination_surface->texture) < 0)
Backend_PrintError("Couldn't set texture as current rendering target: %s", SDL_GetError());
memcpy(glyph_colour_channels, colour_channels, sizeof(glyph_colour_channels));
}
void RenderBackend_DrawGlyph(RenderBackend_Glyph *glyph, long x, long y)
{
if (spritebatch_push(&glyph_batcher, (SPRITEBATCH_U64)glyph, glyph->width, glyph->height, x, y, 1.0f, 1.0f, 0.0f, 0.0f, 0) != 1)
Backend_PrintError("Failed to push glyph to batcher");
}
void RenderBackend_FlushGlyphs(void)
{
if (spritebatch_defrag(&glyph_batcher) != 1)
Backend_PrintError("Couldn't defrag textures");
spritebatch_flush(&glyph_batcher);
}
void RenderBackend_HandleRenderTargetLoss(void)
{
for (RenderBackend_Surface *surface = surface_list_head; surface != NULL; surface = surface->next)
surface->lost = true;
}
void RenderBackend_HandleWindowResize(unsigned int width, unsigned int height)
{
(void)width;
(void)height;
// No problem for us
}