The texture channel modulation used in SDL_RenderCopy().
Defined in SDL_render.h
typedef enum SDL_TextureModulate
{0x00000000, /**< No modulation */
SDL_TEXTUREMODULATE_NONE = 0x00000001, /**< srcC = srcC * color */
SDL_TEXTUREMODULATE_COLOR = 0x00000002 /**< srcA = srcA * alpha */
SDL_TEXTUREMODULATE_ALPHA = } SDL_TextureModulate;