79 lines
2.8 KiB
C
79 lines
2.8 KiB
C
// Mostly for fun (but can very slightly increase performance for large textures). If set to 1, does not clear texture's affiliated and leaves garbage.
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#define ENGINE_GENERIC_TEXTURE_NOCLEAR 1
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struct ENGINE_TEXTURE { int width; int height; void * fe_texture; };
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struct ENGINE_GENERIC_TEXTURE { char * pixels; };
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struct ENGINE_TEXTURE * engine_createTexture(int width,int height) {
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// frontend texture
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char * pixels = engine_malloc(NULL,sizeof(char) * width * height * 4);
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#if (ENGINE_GENERIC_TEXTURE_NOCLEAR == 0)
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memset(pixels,0,sizeof(char) * width * height * 4);
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#endif
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struct ENGINE_GENERIC_TEXTURE * fe_texture = engine_malloc(NULL,sizeof(struct ENGINE_GENERIC_TEXTURE));
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fe_texture->pixels = pixels;
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// engine texture
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struct ENGINE_TEXTURE * texture = engine_malloc(NULL,sizeof(struct ENGINE_TEXTURE));
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texture->width = width;
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texture->height = height;
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texture->fe_texture = (void *)fe_texture;
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return texture;
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}
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struct ENGINE_GENERIC_TEXTURE_COLOR { char r; char g; char b; char a; };
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struct ENGINE_GENERIC_TEXTURE_COLOR engine_generic_texture_color;
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void engine_textureSetColor(char r,char g,char b,char a) {
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engine_generic_texture_color.r = r;
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engine_generic_texture_color.g = g;
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engine_generic_texture_color.b = b;
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engine_generic_texture_color.a = a;
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}
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void engine_textureDrawPixel(struct ENGINE_TEXTURE * texture,int x,int y) {
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char * pixels = ((struct ENGINE_GENERIC_TEXTURE *)(texture->fe_texture))->pixels;
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long pixelIndex = (x + y * texture->width) * 4;
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pixels[pixelIndex + 0] = engine_generic_texture_color.r;
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pixels[pixelIndex + 1] = engine_generic_texture_color.g;
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pixels[pixelIndex + 2] = engine_generic_texture_color.b;
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pixels[pixelIndex + 3] = engine_generic_texture_color.a;
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}
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void engine_textureDestroy(struct ENGINE_TEXTURE * texture) {
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struct ENGINE_GENERIC_TEXTURE * fe_texture = (struct ENGINE_GENERIC_TEXTURE *)(texture->fe_texture);
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engine_free(fe_texture->pixels);
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engine_free(fe_texture);
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engine_free(texture);
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}
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void engine_renderTexture2D(struct ENGINE_TEXTURE * texture,int sx,int sy) {
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char * pixels = ((struct ENGINE_GENERIC_TEXTURE *)(texture->fe_texture))->pixels;
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int ex = sx + texture->width;
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if (ex > engine_width) { ex = engine_width; }
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int ey = sy + texture->height;
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if (ey > engine_width) { ey = engine_height; }
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int x = sx;
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if (x < 0) { x = 0; }
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int y = sy;
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if (y < 0) { y = 0; }
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long pixelIndex = 0;
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while (y < ey) {
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while (x < ex) {
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pixelIndex = ((x - sx) + (y - sy) * texture->width)*4;
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engine_setColor(pixels[pixelIndex],pixels[pixelIndex + 1],pixels[pixelIndex + 2],pixels[pixelIndex + 3]);
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engine_drawPixel(x,y);
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++x;
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}
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x = sx;
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++y;
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}
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}
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void engine_fileToTexture(struct ENGINE_TEXTURE * texture,char * fpath) {
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FILE * f = fopen(fpath,"r");
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fgets(((struct ENGINE_GENERIC_TEXTURE *)(texture->fe_texture))->pixels,texture->width * texture->height,f);
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fclose(f);
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}
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