#include <agar/core.h>
#include <agar/gui.h>

                               /* Bits per pixel: | 1 2 4 8 16 24 32 64 |*/
typedef enum ag_surface_mode { /* --------------- |---------------------|*/
	AG_SURFACE_PACKED,     /* Packed RGB(A)   |       X X  X  X  LG |*/
	AG_SURFACE_INDEXED,    /* Palettized      | X X X X             |*/
	AG_SURFACE_GRAYSCALE   /* Grayscale+Alpha |               X  LG |*/
} AG_SurfaceMode;

typedef struct ag_pixel_format {
	AG_SurfaceMode mode;     /* Image type */
	int BitsPerPixel;        /* Depth (in bits/pixel) */
	int BytesPerPixel;       /* Depth (in bytes/pixel) */
	int PixelsPerByte;       /* Pixels per byte (or 0 if >8bpp) */
	union {
		AG_Palette *palette;       /* Colormap for Indexed */
		AG_GrayscaleMode graymode; /* Grayscale-RGB method */
		struct {
			/*
			 * Number of bits lost by packing each component
			 * into our native representation.
			 */
			Uint8 Rloss, Gloss, Bloss, Aloss;
			/*
			 * Number of bits at the right of each component.
			 */
			Uint8 Rshift, Gshift, Bshift, Ashift;
			/*
			 * Pixel-wide mask over each component.
			 */
			AG_Pixel Rmask, Gmask, Bmask, Amask;
		};
	};
} AG_PixelFormat;

typedef enum ag_alpha_fn {
	AG_ALPHA_ZERO,          /* dst.a = 0 */
	AG_ALPHA_ONE,           /* dst.a = 1 */
	AG_ALPHA_SRC,           /* dst.a = src.a */
	AG_ALPHA_DST,           /* dst.a = dst.a */
	AG_ALPHA_ONE_MINUS_DST, /* dst.a = (1 - dst.a) */
	AG_ALPHA_ONE_MINUS_SRC, /* dst.a = (1 - src.a) */
	AG_ALPHA_OVERLAY        /* dst.a = min(src.a + dst.a, 1) */
} AG_AlphaFn;