src/video/SDL_blit.c
changeset 0 74212992fb08
child 252 e8157fcb3114
     1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/src/video/SDL_blit.c	Thu Apr 26 16:45:43 2001 +0000
     1.3 @@ -0,0 +1,294 @@
     1.4 +/*
     1.5 +    SDL - Simple DirectMedia Layer
     1.6 +    Copyright (C) 1997, 1998, 1999, 2000, 2001  Sam Lantinga
     1.7 +
     1.8 +    This library is free software; you can redistribute it and/or
     1.9 +    modify it under the terms of the GNU Library General Public
    1.10 +    License as published by the Free Software Foundation; either
    1.11 +    version 2 of the License, or (at your option) any later version.
    1.12 +
    1.13 +    This library is distributed in the hope that it will be useful,
    1.14 +    but WITHOUT ANY WARRANTY; without even the implied warranty of
    1.15 +    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    1.16 +    Library General Public License for more details.
    1.17 +
    1.18 +    You should have received a copy of the GNU Library General Public
    1.19 +    License along with this library; if not, write to the Free
    1.20 +    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
    1.21 +
    1.22 +    Sam Lantinga
    1.23 +    slouken@devolution.com
    1.24 +*/
    1.25 +
    1.26 +#ifdef SAVE_RCSID
    1.27 +static char rcsid =
    1.28 + "@(#) $Id$";
    1.29 +#endif
    1.30 +
    1.31 +#include <stdio.h>
    1.32 +#include <stdlib.h>
    1.33 +#include <string.h>
    1.34 +
    1.35 +#include "SDL_error.h"
    1.36 +#include "SDL_video.h"
    1.37 +#include "SDL_sysvideo.h"
    1.38 +#include "SDL_blit.h"
    1.39 +#include "SDL_RLEaccel_c.h"
    1.40 +#include "SDL_pixels_c.h"
    1.41 +#include "SDL_memops.h"
    1.42 +
    1.43 +/* The general purpose software blit routine */
    1.44 +static int SDL_SoftBlit(SDL_Surface *src, SDL_Rect *srcrect,
    1.45 +			SDL_Surface *dst, SDL_Rect *dstrect)
    1.46 +{
    1.47 +	int okay;
    1.48 +	int src_locked;
    1.49 +	int dst_locked;
    1.50 +
    1.51 +	/* Everything is okay at the beginning...  */
    1.52 +	okay = 1;
    1.53 +
    1.54 +	/* Lock the destination if it's in hardware */
    1.55 +	dst_locked = 0;
    1.56 +	if ( dst->flags & (SDL_HWSURFACE|SDL_ASYNCBLIT) ) {
    1.57 +		SDL_VideoDevice *video = current_video;
    1.58 +		SDL_VideoDevice *this  = current_video;
    1.59 +		if ( video->LockHWSurface(this, dst) < 0 ) {
    1.60 +			okay = 0;
    1.61 +		} else {
    1.62 +			dst_locked = 1;
    1.63 +		}
    1.64 +	}
    1.65 +	/* Lock the source if it's in hardware */
    1.66 +	src_locked = 0;
    1.67 +	if ( src->flags & (SDL_HWSURFACE|SDL_ASYNCBLIT) ) {
    1.68 +		SDL_VideoDevice *video = current_video;
    1.69 +		SDL_VideoDevice *this  = current_video;
    1.70 +		if ( video->LockHWSurface(this, src) < 0 ) {
    1.71 +			okay = 0;
    1.72 +		} else {
    1.73 +			src_locked = 1;
    1.74 +		}
    1.75 +	}
    1.76 +
    1.77 +	/* Unencode the destination if it's RLE encoded */
    1.78 +	if ( dst->flags & SDL_RLEACCEL ) {
    1.79 +		SDL_UnRLESurface(dst, 1);
    1.80 +		dst->flags |= SDL_RLEACCEL;	/* save accel'd state */
    1.81 +	}
    1.82 +
    1.83 +	/* Set up source and destination buffer pointers, and BLIT! */
    1.84 +	if ( okay  && srcrect->w && srcrect->h ) {
    1.85 +		SDL_BlitInfo info;
    1.86 +		SDL_loblit RunBlit;
    1.87 +
    1.88 +		/* Set up the blit information */
    1.89 +		info.s_pixels = (Uint8 *)src->pixels + src->offset +
    1.90 +				(Uint16)srcrect->y*src->pitch +
    1.91 +				(Uint16)srcrect->x*src->format->BytesPerPixel;
    1.92 +		info.s_width = srcrect->w;
    1.93 +		info.s_height = srcrect->h;
    1.94 +		info.s_skip=src->pitch-info.s_width*src->format->BytesPerPixel;
    1.95 +		info.d_pixels = (Uint8 *)dst->pixels + dst->offset +
    1.96 +				(Uint16)dstrect->y*dst->pitch +
    1.97 +				(Uint16)dstrect->x*dst->format->BytesPerPixel;
    1.98 +		info.d_width = dstrect->w;
    1.99 +		info.d_height = dstrect->h;
   1.100 +		info.d_skip=dst->pitch-info.d_width*dst->format->BytesPerPixel;
   1.101 +		info.aux_data = src->map->sw_data->aux_data;
   1.102 +		info.src = src->format;
   1.103 +		info.table = src->map->table;
   1.104 +		info.dst = dst->format;
   1.105 +		RunBlit = src->map->sw_data->blit;
   1.106 +
   1.107 +		/* Run the actual software blit */
   1.108 +		RunBlit(&info);
   1.109 +	}
   1.110 +
   1.111 +	/* Re-encode the destination if it's RLE encoded */
   1.112 +	if ( dst->flags & SDL_RLEACCEL ) {
   1.113 +	        dst->flags &= ~SDL_RLEACCEL; /* stop lying */
   1.114 +		SDL_RLESurface(dst);
   1.115 +	}
   1.116 +
   1.117 +	/* We need to unlock the surfaces if they're locked */
   1.118 +	if ( dst_locked ) {
   1.119 +		SDL_VideoDevice *video = current_video;
   1.120 +		SDL_VideoDevice *this  = current_video;
   1.121 +		video->UnlockHWSurface(this, dst);
   1.122 +	} else
   1.123 +	if ( src_locked ) {
   1.124 +		SDL_VideoDevice *video = current_video;
   1.125 +		SDL_VideoDevice *this  = current_video;
   1.126 +		video->UnlockHWSurface(this, src);
   1.127 +	}
   1.128 +	/* Blit is done! */
   1.129 +	return(okay ? 0 : -1);
   1.130 +}
   1.131 +
   1.132 +static void SDL_BlitCopy(SDL_BlitInfo *info)
   1.133 +{
   1.134 +	Uint8 *src, *dst;
   1.135 +	int w, h;
   1.136 +	int srcskip, dstskip;
   1.137 +
   1.138 +	w = info->d_width*info->dst->BytesPerPixel;
   1.139 +	h = info->d_height;
   1.140 +	src = info->s_pixels;
   1.141 +	dst = info->d_pixels;
   1.142 +	srcskip = w+info->s_skip;
   1.143 +	dstskip = w+info->d_skip;
   1.144 +	while ( h-- ) {
   1.145 +		SDL_memcpy(dst, src, w);
   1.146 +		src += srcskip;
   1.147 +		dst += dstskip;
   1.148 +	}
   1.149 +}
   1.150 +
   1.151 +static void SDL_BlitCopyOverlap(SDL_BlitInfo *info)
   1.152 +{
   1.153 +	Uint8 *src, *dst;
   1.154 +	int w, h;
   1.155 +	int srcskip, dstskip;
   1.156 +
   1.157 +	w = info->d_width*info->dst->BytesPerPixel;
   1.158 +	h = info->d_height;
   1.159 +	src = info->s_pixels;
   1.160 +	dst = info->d_pixels;
   1.161 +	srcskip = w+info->s_skip;
   1.162 +	dstskip = w+info->d_skip;
   1.163 +	if ( dst < src ) {
   1.164 +		while ( h-- ) {
   1.165 +			SDL_memcpy(dst, src, w);
   1.166 +			src += srcskip;
   1.167 +			dst += dstskip;
   1.168 +		}
   1.169 +	} else {
   1.170 +		src += ((h-1) * srcskip);
   1.171 +		dst += ((h-1) * dstskip);
   1.172 +		while ( h-- ) {
   1.173 +			SDL_revcpy(dst, src, w);
   1.174 +			src -= srcskip;
   1.175 +			dst -= dstskip;
   1.176 +		}
   1.177 +	}
   1.178 +}
   1.179 +
   1.180 +/* Figure out which of many blit routines to set up on a surface */
   1.181 +int SDL_CalculateBlit(SDL_Surface *surface)
   1.182 +{
   1.183 +	int blit_index;
   1.184 +
   1.185 +	/* Clean everything out to start */
   1.186 +	if ( (surface->flags & SDL_RLEACCEL) == SDL_RLEACCEL ) {
   1.187 +		SDL_UnRLESurface(surface, 1);
   1.188 +	}
   1.189 +	surface->map->sw_blit = NULL;
   1.190 +
   1.191 +	/* Figure out if an accelerated hardware blit is possible */
   1.192 +	surface->flags &= ~SDL_HWACCEL;
   1.193 +	if ( surface->map->identity ) {
   1.194 +		int hw_blit_ok;
   1.195 +
   1.196 +		if ( (surface->flags & SDL_HWSURFACE) == SDL_HWSURFACE ) {
   1.197 +			/* We only support accelerated blitting to hardware */
   1.198 +			if ( surface->map->dst->flags & SDL_HWSURFACE ) {
   1.199 +				hw_blit_ok = current_video->info.blit_hw;
   1.200 +			} else {
   1.201 +				hw_blit_ok = 0;
   1.202 +			}
   1.203 +			if (hw_blit_ok && (surface->flags & SDL_SRCCOLORKEY)) {
   1.204 +				hw_blit_ok = current_video->info.blit_hw_CC;
   1.205 +			}
   1.206 +			if ( hw_blit_ok && (surface->flags & SDL_SRCALPHA) ) {
   1.207 +				hw_blit_ok = current_video->info.blit_hw_A;
   1.208 +			}
   1.209 +		} else {
   1.210 +			/* We only support accelerated blitting to hardware */
   1.211 +			if ( surface->map->dst->flags & SDL_HWSURFACE ) {
   1.212 +				hw_blit_ok = current_video->info.blit_sw;
   1.213 +			} else {
   1.214 +				hw_blit_ok = 0;
   1.215 +			}
   1.216 +			if (hw_blit_ok && (surface->flags & SDL_SRCCOLORKEY)) {
   1.217 +				hw_blit_ok = current_video->info.blit_sw_CC;
   1.218 +			}
   1.219 +			if ( hw_blit_ok && (surface->flags & SDL_SRCALPHA) ) {
   1.220 +				hw_blit_ok = current_video->info.blit_sw_A;
   1.221 +			}
   1.222 +		}
   1.223 +		if ( hw_blit_ok ) {
   1.224 +			SDL_VideoDevice *video = current_video;
   1.225 +			SDL_VideoDevice *this  = current_video;
   1.226 +			video->CheckHWBlit(this, surface, surface->map->dst);
   1.227 +		}
   1.228 +	}
   1.229 +
   1.230 +	/* Get the blit function index, based on surface mode */
   1.231 +	/* { 0 = nothing, 1 = colorkey, 2 = alpha, 3 = colorkey+alpha } */
   1.232 +	blit_index = 0;
   1.233 +	blit_index |= (!!(surface->flags & SDL_SRCCOLORKEY))      << 0;
   1.234 +	if ( surface->flags & SDL_SRCALPHA
   1.235 +	     && (surface->format->alpha != SDL_ALPHA_OPAQUE
   1.236 +		 || surface->format->Amask) ) {
   1.237 +	        blit_index |= 2;
   1.238 +	}
   1.239 +
   1.240 +	/* Check for special "identity" case -- copy blit */
   1.241 +	if ( surface->map->identity && blit_index == 0 ) {
   1.242 +	        surface->map->sw_data->blit = SDL_BlitCopy;
   1.243 +
   1.244 +		/* Handle overlapping blits on the same surface */
   1.245 +		if ( surface == surface->map->dst ) {
   1.246 +		        surface->map->sw_data->blit = SDL_BlitCopyOverlap;
   1.247 +		}
   1.248 +	} else {
   1.249 +		if ( surface->format->BitsPerPixel < 8 ) {
   1.250 +			surface->map->sw_data->blit =
   1.251 +			    SDL_CalculateBlit0(surface, blit_index);
   1.252 +		} else {
   1.253 +			switch ( surface->format->BytesPerPixel ) {
   1.254 +			    case 1:
   1.255 +				surface->map->sw_data->blit =
   1.256 +				    SDL_CalculateBlit1(surface, blit_index);
   1.257 +				break;
   1.258 +			    case 2:
   1.259 +			    case 3:
   1.260 +			    case 4:
   1.261 +				surface->map->sw_data->blit =
   1.262 +				    SDL_CalculateBlitN(surface, blit_index);
   1.263 +				break;
   1.264 +			    default:
   1.265 +				surface->map->sw_data->blit = NULL;
   1.266 +				break;
   1.267 +			}
   1.268 +		}
   1.269 +	}
   1.270 +	/* Make sure we have a blit function */
   1.271 +	if ( surface->map->sw_data->blit == NULL ) {
   1.272 +		SDL_InvalidateMap(surface->map);
   1.273 +		SDL_SetError("Blit combination not supported");
   1.274 +		return(-1);
   1.275 +	}
   1.276 +
   1.277 +	/* Choose software blitting function */
   1.278 +	if(surface->flags & SDL_RLEACCELOK
   1.279 +	   && (surface->flags & SDL_HWACCEL) != SDL_HWACCEL) {
   1.280 +
   1.281 +	        if(surface->map->identity
   1.282 +		   && (blit_index == 1
   1.283 +		       || (blit_index == 3 && !surface->format->Amask))) {
   1.284 +		        if ( SDL_RLESurface(surface) == 0 )
   1.285 +			        surface->map->sw_blit = SDL_RLEBlit;
   1.286 +		} else if(blit_index == 2 && surface->format->Amask) {
   1.287 +		        if ( SDL_RLESurface(surface) == 0 )
   1.288 +			        surface->map->sw_blit = SDL_RLEAlphaBlit;
   1.289 +		}
   1.290 +	}
   1.291 +	
   1.292 +	if ( surface->map->sw_blit == NULL ) {
   1.293 +		surface->map->sw_blit = SDL_SoftBlit;
   1.294 +	}
   1.295 +	return(0);
   1.296 +}
   1.297 +