Adam Strzelecki to SDL When graphic card has no GL_ARB_texture_rectangle YUV textures mapped with SDL_RenderCopy are stretched 2x horizontally, so only left half of texture is visible. This is due: data->texw = (GLfloat) (texture->w) / texture_w; data->texh = (GLfloat) texture->h / texture_h; But afterwards texture_w /= 2 for YUV texture, but data->texw stays as it was before, while it should be multiplied 2x. This bug can be seen in any program setting env variables: GL_APPLE_ycbcr_422=0 GL_EXT_texture_rectangle=0 GL_ARB_texture_rectangle=0