view src/video/SDL_blit_1.c @ 641:df178851293b

Date: 28 Jun 2003 22:42:52 +0100 From: Alan Swanson Subject: Re: [SDL] New XFree 4.3 Video Mode Patch I have a wee amendment that moves the qsort in set_best_resolution to only occur after failing to find an exact match only. This would make absolutely sure we get a user set mode. While I've never had any problems for my normal resolutions (1280x1024, 1024x768, 800x600 & 640,480) while closely examining the output from qsort I've noticed it doesn't seem to sort the modes fully. These is one definite wrong at 1152x768 and a few that just look wrong to me. From a program (attached) I made to examine this more easily. X has sorted its mode list using the same method as ours (plus frequency), and our user modes get inserted without any other movement. On the patch I've made I've also changed cmpmodes to sort on vertical resolution and then horizontal. Ie vertical is now most significant bit.
author Sam Lantinga <slouken@libsdl.org>
date Sat, 28 Jun 2003 21:52:26 +0000
parents f6ffac90895c
children b8d311d90021
line wrap: on
line source

/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002  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;
}