view src/video/SDL_blit_1.c @ 855:aa4ac9e65d92

I noticed MacOSX SDL sets up working directory to parent of executable. On BeOS is should setup it the same way, but it only does when Tracker wasn't restarted. I checked code and it looks like a hack to me :( It looks for env variable and than comapres it to default when OpenTracker was started after boot, and wasn't restarted. That's probably ok, for that exact case. Unfortunetly that variable isn't always like that. For example, after Tracker crashes and is restarted, env variable most probably is different (depends on how Tracker was restarted, by what application, etc... for example: i have launcher application from which i can restart Tracker, and after that nev variable points to that application's directory, not Tracker's).
author Sam Lantinga <slouken@libsdl.org>
date Tue, 24 Feb 2004 18:58:40 +0000
parents b8d311d90021
children c9b51268668f
line wrap: on
line source

/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2004 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
    slouken@libsdl.org
*/

#ifdef SAVE_RCSID
static char rcsid =
 "@(#) $Id$";
#endif

#include <stdio.h>

#include "SDL_types.h"
#include "SDL_video.h"
#include "SDL_blit.h"
#include "SDL_sysvideo.h"
#include "SDL_endian.h"

/* Functions to blit from 8-bit surfaces to other surfaces */

static void Blit1to1(SDL_BlitInfo *info)
{
#ifndef USE_DUFFS_LOOP
	int c;
#endif
	int width, height;
	Uint8 *src, *map, *dst;
	int srcskip, dstskip;

	/* Set up some basic variables */
	width = info->d_width;
	height = info->d_height;
	src = info->s_pixels;
	srcskip = info->s_skip;
	dst = info->d_pixels;
	dstskip = info->d_skip;
	map = info->table;

	while ( height-- ) {
#ifdef USE_DUFFS_LOOP
		DUFFS_LOOP(
			{
			  *dst = map[*src];
			}
			dst++;
			src++;
		, width);
#else
		for ( c=width; c; --c ) {
		        *dst = map[*src];
			dst++;
			src++;
		}
#endif
		src += srcskip;
		dst += dstskip;
	}
}
/* This is now endian dependent */
#if ( SDL_BYTEORDER == SDL_LIL_ENDIAN )
#define HI	1
#define LO	0
#else /* ( SDL_BYTEORDER == SDL_BIG_ENDIAN ) */
#define HI	0
#define LO	1
#endif
static void Blit1to2(SDL_BlitInfo *info)
{
#ifndef USE_DUFFS_LOOP
	int c;
#endif
	int width, height;
	Uint8 *src, *dst;
	Uint16 *map;
	int srcskip, dstskip;

	/* Set up some basic variables */
	width = info->d_width;
	height = info->d_height;
	src = info->s_pixels;
	srcskip = info->s_skip;
	dst = info->d_pixels;
	dstskip = info->d_skip;
	map = (Uint16 *)info->table;

#ifdef USE_DUFFS_LOOP
	while ( height-- ) {
		DUFFS_LOOP(
		{
			*(Uint16 *)dst = map[*src++];
			dst += 2;
		},
		width);
		src += srcskip;
		dst += dstskip;
	}
#else
	/* Memory align at 4-byte boundary, if necessary */
	if ( (long)dst & 0x03 ) {
		/* Don't do anything if width is 0 */
		if ( width == 0 ) {
			return;
		}
		--width;

		while ( height-- ) {
			/* Perform copy alignment */
			*(Uint16 *)dst = map[*src++];
			dst += 2;

			/* Copy in 4 pixel chunks */
			for ( c=width/4; c; --c ) {
				*(Uint32 *)dst =
					(map[src[HI]]<<16)|(map[src[LO]]);
				src += 2;
				dst += 4;
				*(Uint32 *)dst =
					(map[src[HI]]<<16)|(map[src[LO]]);
				src += 2;
				dst += 4;
			}
			/* Get any leftovers */
			switch (width & 3) {
				case 3:
					*(Uint16 *)dst = map[*src++];
					dst += 2;
				case 2:
					*(Uint32 *)dst =
					  (map[src[HI]]<<16)|(map[src[LO]]);
					src += 2;
					dst += 4;
					break;
				case 1:
					*(Uint16 *)dst = map[*src++];
					dst += 2;
					break;
			}
			src += srcskip;
			dst += dstskip;
		}
	} else { 
		while ( height-- ) {
			/* Copy in 4 pixel chunks */
			for ( c=width/4; c; --c ) {
				*(Uint32 *)dst =
					(map[src[HI]]<<16)|(map[src[LO]]);
				src += 2;
				dst += 4;
				*(Uint32 *)dst =
					(map[src[HI]]<<16)|(map[src[LO]]);
				src += 2;
				dst += 4;
			}
			/* Get any leftovers */
			switch (width & 3) {
				case 3:
					*(Uint16 *)dst = map[*src++];
					dst += 2;
				case 2:
					*(Uint32 *)dst =
					  (map[src[HI]]<<16)|(map[src[LO]]);
					src += 2;
					dst += 4;
					break;
				case 1:
					*(Uint16 *)dst = map[*src++];
					dst += 2;
					break;
			}
			src += srcskip;
			dst += dstskip;
		}
	}
#endif /* USE_DUFFS_LOOP */
}
static void Blit1to3(SDL_BlitInfo *info)
{
#ifndef USE_DUFFS_LOOP
	int c;
#endif
	int o;
	int width, height;
	Uint8 *src, *map, *dst;
	int srcskip, dstskip;

	/* Set up some basic variables */
	width = info->d_width;
	height = info->d_height;
	src = info->s_pixels;
	srcskip = info->s_skip;
	dst = info->d_pixels;
	dstskip = info->d_skip;
	map = info->table;

	while ( height-- ) {
#ifdef USE_DUFFS_LOOP
		DUFFS_LOOP(
			{
				o = *src * 4;
				dst[0] = map[o++];
				dst[1] = map[o++];
				dst[2] = map[o++];
			}
			src++;
			dst += 3;
		, width);
#else
		for ( c=width; c; --c ) {
			o = *src * 4;
			dst[0] = map[o++];
			dst[1] = map[o++];
			dst[2] = map[o++];
			src++;
			dst += 3;
		}
#endif /* USE_DUFFS_LOOP */
		src += srcskip;
		dst += dstskip;
	}
}
static void Blit1to4(SDL_BlitInfo *info)
{
#ifndef USE_DUFFS_LOOP
	int c;
#endif
	int width, height;
	Uint8 *src;
	Uint32 *map, *dst;
	int srcskip, dstskip;

	/* Set up some basic variables */
	width = info->d_width;
	height = info->d_height;
	src = info->s_pixels;
	srcskip = info->s_skip;
	dst = (Uint32 *)info->d_pixels;
	dstskip = info->d_skip/4;
	map = (Uint32 *)info->table;

	while ( height-- ) {
#ifdef USE_DUFFS_LOOP
		DUFFS_LOOP(
			*dst++ = map[*src++];
		, width);
#else
		for ( c=width/4; c; --c ) {
			*dst++ = map[*src++];
			*dst++ = map[*src++];
			*dst++ = map[*src++];
			*dst++ = map[*src++];
		}
		switch ( width & 3 ) {
			case 3:
				*dst++ = map[*src++];
			case 2:
				*dst++ = map[*src++];
			case 1:
				*dst++ = map[*src++];
		}
#endif /* USE_DUFFS_LOOP */
		src += srcskip;
		dst += dstskip;
	}
}

static void Blit1to1Key(SDL_BlitInfo *info)
{
	int width = info->d_width;
	int height = info->d_height;
	Uint8 *src = info->s_pixels;
	int srcskip = info->s_skip;
	Uint8 *dst = info->d_pixels;
	int dstskip = info->d_skip;
	Uint8 *palmap = info->table;
	Uint32 ckey = info->src->colorkey;
        
	if ( palmap ) {
		while ( height-- ) {
			DUFFS_LOOP(
			{
				if ( *src != ckey ) {
				  *dst = palmap[*src];
				}
				dst++;
				src++;
			},
			width);
			src += srcskip;
			dst += dstskip;
		}
	} else {
		while ( height-- ) {
			DUFFS_LOOP(
			{
				if ( *src != ckey ) {
				  *dst = *src;
				}
				dst++;
				src++;
			},
			width);
			src += srcskip;
			dst += dstskip;
		}
	}
}

static void Blit1to2Key(SDL_BlitInfo *info)
{
	int width = info->d_width;
	int height = info->d_height;
	Uint8 *src = info->s_pixels;
	int srcskip = info->s_skip;
	Uint16 *dstp = (Uint16 *)info->d_pixels;
	int dstskip = info->d_skip;
	Uint16 *palmap = (Uint16 *)info->table;
	Uint32 ckey = info->src->colorkey;

	/* Set up some basic variables */
	dstskip /= 2;

	while ( height-- ) {
		DUFFS_LOOP(
		{
			if ( *src != ckey ) {
				*dstp=palmap[*src];
			}
			src++;
			dstp++;
		},
		width);
		src += srcskip;
		dstp += dstskip;
	}
}

static void Blit1to3Key(SDL_BlitInfo *info)
{
	int width = info->d_width;
	int height = info->d_height;
	Uint8 *src = info->s_pixels;
	int srcskip = info->s_skip;
	Uint8 *dst = info->d_pixels;
	int dstskip = info->d_skip;
	Uint8 *palmap = info->table;
	Uint32 ckey = info->src->colorkey;
	int o;

	while ( height-- ) {
		DUFFS_LOOP(
		{
			if ( *src != ckey ) {
				o = *src * 4;
				dst[0] = palmap[o++];
				dst[1] = palmap[o++];
				dst[2] = palmap[o++];
			}
			src++;
			dst += 3;
		},
		width);
		src += srcskip;
		dst += dstskip;
	}
}

static void Blit1to4Key(SDL_BlitInfo *info)
{
	int width = info->d_width;
	int height = info->d_height;
	Uint8 *src = info->s_pixels;
	int srcskip = info->s_skip;
	Uint32 *dstp = (Uint32 *)info->d_pixels;
	int dstskip = info->d_skip;
	Uint32 *palmap = (Uint32 *)info->table;
	Uint32 ckey = info->src->colorkey;

	/* Set up some basic variables */
	dstskip /= 4;

	while ( height-- ) {
		DUFFS_LOOP(
		{
			if ( *src != ckey ) {
				*dstp = palmap[*src];
			}
			src++;
			dstp++;
		},
		width);
		src += srcskip;
		dstp += dstskip;
	}
}

static void Blit1toNAlpha(SDL_BlitInfo *info)
{
	int width = info->d_width;
	int height = info->d_height;
	Uint8 *src = info->s_pixels;
	int srcskip = info->s_skip;
	Uint8 *dst = info->d_pixels;
	int dstskip = info->d_skip;
	SDL_PixelFormat *dstfmt = info->dst;
	const SDL_Color *srcpal	= info->src->palette->colors;
	int dstbpp;
	const int A = info->src->alpha;

	/* Set up some basic variables */
	dstbpp = dstfmt->BytesPerPixel;

	while ( height-- ) {
	        int sR, sG, sB;
		int dR, dG, dB;
	    	DUFFS_LOOP4(
			{
			        Uint32 pixel;
				sR = srcpal[*src].r;
				sG = srcpal[*src].g;
				sB = srcpal[*src].b;
				DISEMBLE_RGB(dst, dstbpp, dstfmt,
					     pixel, dR, dG, dB);
				ALPHA_BLEND(sR, sG, sB, A, dR, dG, dB);
			  	ASSEMBLE_RGB(dst, dstbpp, dstfmt, dR, dG, dB);
				src++;
				dst += dstbpp;
			},
			width);
		src += srcskip;
		dst += dstskip;
	}
}

static void Blit1toNAlphaKey(SDL_BlitInfo *info)
{
	int width = info->d_width;
	int height = info->d_height;
	Uint8 *src = info->s_pixels;
	int srcskip = info->s_skip;
	Uint8 *dst = info->d_pixels;
	int dstskip = info->d_skip;
	SDL_PixelFormat *srcfmt = info->src;
	SDL_PixelFormat *dstfmt = info->dst;
	const SDL_Color *srcpal	= info->src->palette->colors;
	Uint32 ckey = srcfmt->colorkey;
	int dstbpp;
	const int A = srcfmt->alpha;

	/* Set up some basic variables */
	dstbpp = dstfmt->BytesPerPixel;

	while ( height-- ) {
	        int sR, sG, sB;
		int dR, dG, dB;
		DUFFS_LOOP(
		{
			if ( *src != ckey ) {
			        Uint32 pixel;
				sR = srcpal[*src].r;
				sG = srcpal[*src].g;
				sB = srcpal[*src].b;
				DISEMBLE_RGB(dst, dstbpp, dstfmt,
							pixel, dR, dG, dB);
				ALPHA_BLEND(sR, sG, sB, A, dR, dG, dB);
			  	ASSEMBLE_RGB(dst, dstbpp, dstfmt, dR, dG, dB);
			}
			src++;
			dst += dstbpp;
		},
		width);
		src += srcskip;
		dst += dstskip;
	}
}

static SDL_loblit one_blit[] = {
	NULL, Blit1to1, Blit1to2, Blit1to3, Blit1to4
};

static SDL_loblit one_blitkey[] = {
        NULL, Blit1to1Key, Blit1to2Key, Blit1to3Key, Blit1to4Key
};

SDL_loblit SDL_CalculateBlit1(SDL_Surface *surface, int blit_index)
{
	int which;
	SDL_PixelFormat *dstfmt;

	dstfmt = surface->map->dst->format;
	if ( dstfmt->BitsPerPixel < 8 ) {
		which = 0;
	} else {
		which = dstfmt->BytesPerPixel;
	}
	switch(blit_index) {
	case 0:			/* copy */
	    return one_blit[which];

	case 1:			/* colorkey */
	    return one_blitkey[which];

	case 2:			/* alpha */
	    /* Supporting 8bpp->8bpp alpha is doable but requires lots of
	       tables which consume space and takes time to precompute,
	       so is better left to the user */
	    return which >= 2 ? Blit1toNAlpha : NULL;

	case 3:			/* alpha + colorkey */
	    return which >= 2 ? Blit1toNAlphaKey : NULL;

	}
	return NULL;
}