/*

    SDL - Simple DirectMedia Layer

    Copyright (C) 1997, 1998, 1999, 2000, 2001  Sam Lantinga

    This library is free software; you can redistribute it and/or

    modify it under the terms of the GNU Library General Public

    License as published by the Free Software Foundation; either

    version 2 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,

    but WITHOUT ANY WARRANTY; without even the implied warranty of

    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

    Library General Public License for more details.

    You should have received a copy of the GNU Library General Public

    License along with this library; if not, write to the Free

    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

    Sam Lantinga

*/

#ifdef SAVE_RCSID

static char rcsid =

 "@(#) $Id$";

#endif

#ifndef _SDL_blit_h

#define _SDL_blit_h

#include "SDL_endian.h"

/* The structure passed to the low level blit functions */

typedef struct {

	Uint8 *s_pixels;

	int s_width;

	int s_height;

	int s_skip;

	Uint8 *d_pixels;

	int d_width;

	int d_height;

	int d_skip;

	void *aux_data;

	SDL_PixelFormat *src;

	Uint8 *table;

	SDL_PixelFormat *dst;

} SDL_BlitInfo;

/* The type definition for the low level blit functions */

typedef void (*SDL_loblit)(SDL_BlitInfo *info);

/* This is the private info structure for software accelerated blits */

struct private_swaccel {

	SDL_loblit blit;

	void *aux_data;

};

/* Blit mapping definition */

typedef struct SDL_BlitMap {

	SDL_Surface *dst;

	int identity;

	Uint8 *table;

	SDL_blit hw_blit;

	SDL_blit sw_blit;

	struct private_hwaccel *hw_data;

	struct private_swaccel *sw_data;

	/* the version count matches the destination; mismatch indicates

	   an invalid mapping */

        unsigned int format_version;

} SDL_BlitMap;

/* Functions found in SDL_blit.c */

extern int SDL_CalculateBlit(SDL_Surface *surface);

/* Functions found in SDL_blit_{0,1,N,A}.c */

extern SDL_loblit SDL_CalculateBlit0(SDL_Surface *surface, int complex);

extern SDL_loblit SDL_CalculateBlit1(SDL_Surface *surface, int complex);

extern SDL_loblit SDL_CalculateBlitN(SDL_Surface *surface, int complex);

extern SDL_loblit SDL_CalculateAlphaBlit(SDL_Surface *surface, int complex);

/*

 * Useful macros for blitting routines

 */

#define FORMAT_EQUAL(A, B)						\

    ((A)->BitsPerPixel == (B)->BitsPerPixel				\

     && ((A)->Rmask == (B)->Rmask) && ((A)->Amask == (B)->Amask))

/* Load pixel of the specified format from a buffer and get its R-G-B values */

/* FIXME: rescale values to 0..255 here? */

#define RGB_FROM_PIXEL(pixel, fmt, r, g, b)				\

{									\

	r = (((pixel&fmt->Rmask)>>fmt->Rshift)<<fmt->Rloss); 		\

	g = (((pixel&fmt->Gmask)>>fmt->Gshift)<<fmt->Gloss); 		\

	b = (((pixel&fmt->Bmask)>>fmt->Bshift)<<fmt->Bloss); 		\

}

#define RGB_FROM_RGB565(pixel, r, g, b)					\

{									\

	r = (((pixel&0xF800)>>11)<<3);		 			\

	g = (((pixel&0x07E0)>>5)<<2); 					\

	b = ((pixel&0x001F)<<3); 					\

}

#define RGB_FROM_RGB555(pixel, r, g, b)					\

{									\

	r = (((pixel&0x7C00)>>10)<<3);		 			\

	g = (((pixel&0x03E0)>>5)<<3); 					\

	b = ((pixel&0x001F)<<3); 					\

}

#define RGB_FROM_RGB888(pixel, r, g, b)					\

{									\

	r = ((pixel&0xFF0000)>>16);		 			\

	g = ((pixel&0xFF00)>>8);		 			\

	b = (pixel&0xFF);			 			\

}

#define RETRIEVE_RGB_PIXEL(buf, bpp, pixel)				   \

do {									   \

	switch (bpp) {							   \

		case 2:							   \

			pixel = *((Uint16 *)(buf));			   \

		break;							   \

									   \

		case 3: {						   \

		        Uint8 *B = (Uint8 *)(buf);			   \

			if(SDL_BYTEORDER == SDL_LIL_ENDIAN) {		   \

			        pixel = B[0] + (B[1] << 8) + (B[2] << 16); \

			} else {					   \

			        pixel = (B[0] << 16) + (B[1] << 8) + B[2]; \

			}						   \

		}							   \

		break;							   \

									   \

		case 4:							   \

			pixel = *((Uint32 *)(buf));			   \

		break;							   \

									   \

		default:						   \

			pixel = 0; /* appease gcc */			   \

		break;							   \

	}								   \

} while(0)

#define DISEMBLE_RGB(buf, bpp, fmt, pixel, r, g, b)			   \

do {									   \

	switch (bpp) {							   \

		case 2:							   \

			pixel = *((Uint16 *)(buf));			   \

		break;							   \

									   \

		case 3: {						   \

		        Uint8 *B = (Uint8 *)buf;			   \

			if(SDL_BYTEORDER == SDL_LIL_ENDIAN) {		   \

			        pixel = B[0] + (B[1] << 8) + (B[2] << 16); \

			} else {					   \

			        pixel = (B[0] << 16) + (B[1] << 8) + B[2]; \

			}						   \

		}							   \

		break;							   \

									   \

		case 4:							   \

			pixel = *((Uint32 *)(buf));			   \

		break;							   \

									   \

	        default:						   \

		        pixel = 0;	/* prevent gcc from complaining */ \

		break;							   \

	}								   \

	RGB_FROM_PIXEL(pixel, fmt, r, g, b);				   \

} while(0)

/* Assemble R-G-B values into a specified pixel format and store them */

#define PIXEL_FROM_RGB(pixel, fmt, r, g, b)				\

{									\

	pixel = ((r>>fmt->Rloss)<<fmt->Rshift)|				\

		((g>>fmt->Gloss)<<fmt->Gshift)|				\

		((b>>fmt->Bloss)<<fmt->Bshift);				\

}

#define RGB565_FROM_RGB(pixel, r, g, b)					\

{									\

	pixel = ((r>>3)<<11)|((g>>2)<<5)|(b>>3);			\

}

#define RGB555_FROM_RGB(pixel, r, g, b)					\

{									\

	pixel = ((r>>3)<<10)|((g>>3)<<5)|(b>>3);			\

}

#define RGB888_FROM_RGB(pixel, r, g, b)					\

{									\

	pixel = (r<<16)|(g<<8)|b;					\

}

#define ASSEMBLE_RGB(buf, bpp, fmt, r, g, b) 				\

{									\

	switch (bpp) {							\

		case 2: {						\

			Uint16 pixel;					\

									\

			PIXEL_FROM_RGB(pixel, fmt, r, g, b);		\

			*((Uint16 *)(buf)) = pixel;			\

		}							\

		break;							\

									\

		case 3: {						\

                        if(SDL_BYTEORDER == SDL_LIL_ENDIAN) {		\

			        *((buf)+fmt->Rshift/8) = r;		\

				*((buf)+fmt->Gshift/8) = g;		\

				*((buf)+fmt->Bshift/8) = b;		\

			} else {					\

			        *((buf)+2-fmt->Rshift/8) = r;		\

				*((buf)+2-fmt->Gshift/8) = g;		\

				*((buf)+2-fmt->Bshift/8) = b;		\

			}						\

		}							\

		break;							\

									\

		case 4: {						\

			Uint32 pixel;					\

									\

			PIXEL_FROM_RGB(pixel, fmt, r, g, b);		\

			*((Uint32 *)(buf)) = pixel;			\

		}							\

		break;							\

	}								\

}

#define ASSEMBLE_RGB_AMASK(buf, bpp, fmt, r, g, b, Amask)		\

{									\

	switch (bpp) {							\

		case 2: {						\

			Uint16 *bufp;					\

			Uint16 pixel;					\

									\

			bufp = (Uint16 *)buf;				\

			PIXEL_FROM_RGB(pixel, fmt, r, g, b);		\

			*bufp = pixel | (*bufp & Amask);		\

		}							\

		break;							\

									\

		case 3: {						\

                        if(SDL_BYTEORDER == SDL_LIL_ENDIAN) {		\

			        *((buf)+fmt->Rshift/8) = r;		\

				*((buf)+fmt->Gshift/8) = g;		\

				*((buf)+fmt->Bshift/8) = b;		\

			} else {					\

			        *((buf)+2-fmt->Rshift/8) = r;		\

				*((buf)+2-fmt->Gshift/8) = g;		\

				*((buf)+2-fmt->Bshift/8) = b;		\

			}						\

		}							\

		break;							\

									\

		case 4: {						\

			Uint32 *bufp;					\

			Uint32 pixel;					\

									\

			bufp = (Uint32 *)buf;				\

			PIXEL_FROM_RGB(pixel, fmt, r, g, b);		\

			*bufp = pixel | (*bufp & Amask);		\

		}							\

		break;							\

	}								\

}

/* FIXME: Should we rescale alpha into 0..255 here? */

#define RGBA_FROM_PIXEL(pixel, fmt, r, g, b, a)				\

{									\

	r = ((pixel&fmt->Rmask)>>fmt->Rshift)<<fmt->Rloss; 		\

	g = ((pixel&fmt->Gmask)>>fmt->Gshift)<<fmt->Gloss; 		\

	b = ((pixel&fmt->Bmask)>>fmt->Bshift)<<fmt->Bloss; 		\

	a = ((pixel&fmt->Amask)>>fmt->Ashift)<<fmt->Aloss;	 	\

}

#define RGBA_FROM_8888(pixel, fmt, r, g, b, a)	\

{						\

	r = (pixel&fmt->Rmask)>>fmt->Rshift;	\

	g = (pixel&fmt->Gmask)>>fmt->Gshift;	\

	b = (pixel&fmt->Bmask)>>fmt->Bshift;	\

	a = (pixel&fmt->Amask)>>fmt->Ashift;	\

}

#define RGBA_FROM_RGBA8888(pixel, r, g, b, a)				\

{									\

	r = (pixel>>24);						\

	g = ((pixel>>16)&0xFF);						\

	b = ((pixel>>8)&0xFF);						\

	a = (pixel&0xFF);						\

}

#define RGBA_FROM_ARGB8888(pixel, r, g, b, a)				\

{									\

	r = ((pixel>>16)&0xFF);						\

	g = ((pixel>>8)&0xFF);						\

	b = (pixel&0xFF);						\

	a = (pixel>>24);						\

}

#define RGBA_FROM_ABGR8888(pixel, r, g, b, a)				\

{									\

	r = (pixel&0xFF);						\

	g = ((pixel>>8)&0xFF);						\

	b = ((pixel>>16)&0xFF);						\

	a = (pixel>>24);						\

}

#define DISEMBLE_RGBA(buf, bpp, fmt, pixel, r, g, b, a)			   \

do {									   \

	switch (bpp) {							   \

		case 2:							   \

			pixel = *((Uint16 *)(buf));			   \

		break;							   \

									   \

		case 3:	{/* FIXME: broken code (no alpha) */		   \

		        Uint8 *b = (Uint8 *)buf;			   \

			if(SDL_BYTEORDER == SDL_LIL_ENDIAN) {		   \

			        pixel = b[0] + (b[1] << 8) + (b[2] << 16); \

			} else {					   \

			        pixel = (b[0] << 16) + (b[1] << 8) + b[2]; \

			}						   \

		}							   \

		break;							   \

									   \

		case 4:							   \

			pixel = *((Uint32 *)(buf));			   \

		break;							   \

									   \

		default:						   \

		        pixel = 0; /* stop gcc complaints */		   \

		break;							   \

	}								   \

	RGBA_FROM_PIXEL(pixel, fmt, r, g, b, a);			   \

	pixel &= ~fmt->Amask;						   \

} while(0)

/* FIXME: this isn't correct, especially for Alpha (maximum != 255) */

#define PIXEL_FROM_RGBA(pixel, fmt, r, g, b, a)				\

{									\

	pixel = ((r>>fmt->Rloss)<<fmt->Rshift)|				\

		((g>>fmt->Gloss)<<fmt->Gshift)|				\

		((b>>fmt->Bloss)<<fmt->Bshift)|				\

		((a<<fmt->Aloss)<<fmt->Ashift);				\

}

#define ASSEMBLE_RGBA(buf, bpp, fmt, r, g, b, a)			\

{									\

	switch (bpp) {							\

		case 2: {						\

			Uint16 pixel;					\

									\

			PIXEL_FROM_RGBA(pixel, fmt, r, g, b, a);	\

			*((Uint16 *)(buf)) = pixel;			\

		}							\

		break;							\

									\

		case 3: { /* FIXME: broken code (no alpha) */		\

                        if(SDL_BYTEORDER == SDL_LIL_ENDIAN) {		\

			        *((buf)+fmt->Rshift/8) = r;		\

				*((buf)+fmt->Gshift/8) = g;		\

				*((buf)+fmt->Bshift/8) = b;		\

			} else {					\

			        *((buf)+2-fmt->Rshift/8) = r;		\

				*((buf)+2-fmt->Gshift/8) = g;		\

				*((buf)+2-fmt->Bshift/8) = b;		\

			}						\

		}							\

		break;							\

									\

		case 4: {						\

			Uint32 pixel;					\

									\

			PIXEL_FROM_RGBA(pixel, fmt, r, g, b, a);	\

			*((Uint32 *)(buf)) = pixel;			\

		}							\

		break;							\

	}								\

}

/* Blend the RGB values of two pixels based on a source alpha value */

#define ALPHA_BLEND(sR, sG, sB, A, dR, dG, dB)	\

do {						\

	dR = (((sR-dR)*(A))>>8)+dR;		\

	dG = (((sG-dG)*(A))>>8)+dG;		\

	dB = (((sB-dB)*(A))>>8)+dB;		\

} while(0)

/* This is a very useful loop for optimizing blitters */

#define USE_DUFFS_LOOP

#ifdef USE_DUFFS_LOOP

/* 8-times unrolled loop */

#define DUFFS_LOOP8(pixel_copy_increment, width)			\

{ int n = (width+7)/8;							\

	switch (width & 7) {						\

	case 0: do {	pixel_copy_increment;				\

	case 7:		pixel_copy_increment;				\

	case 6:		pixel_copy_increment;				\

	case 5:		pixel_copy_increment;				\

	case 4:		pixel_copy_increment;				\

	case 3:		pixel_copy_increment;				\

	case 2:		pixel_copy_increment;				\

	case 1:		pixel_copy_increment;				\

		} while ( --n > 0 );					\

	}								\

}

/* 4-times unrolled loop */

#define DUFFS_LOOP4(pixel_copy_increment, width)			\

{ int n = (width+3)/4;							\

	switch (width & 3) {						\

	case 0: do {	pixel_copy_increment;				\

	case 3:		pixel_copy_increment;				\

	case 2:		pixel_copy_increment;				\

	case 1:		pixel_copy_increment;				\

		} while ( --n > 0 );					\

	}								\

}

/* Use the 8-times version of the loop by default */

#define DUFFS_LOOP(pixel_copy_increment, width)				\

	DUFFS_LOOP8(pixel_copy_increment, width)

#else

/* Don't use Duff's device to unroll loops */

#define DUFFS_LOOP(pixel_copy_increment, width)				\

{ int n;								\

	for ( n=width; n > 0; --n ) {					\

		pixel_copy_increment;					\

	}								\

}

#define DUFFS_LOOP8(pixel_copy_increment, width)			\

	DUFFS_LOOP(pixel_copy_increment, width)

#define DUFFS_LOOP4(pixel_copy_increment, width)			\

	DUFFS_LOOP(pixel_copy_increment, width)

#endif /* USE_DUFFS_LOOP */

/* Prevent Visual C++ 6.0 from printing out stupid warnings */

#if defined(_MSC_VER) && (_MSC_VER >= 600)

#pragma warning(disable: 4550)

#endif

#endif /* _SDL_blit_h */