src/video/SDL_blit.c
author Ryan C. Gordon <icculus@icculus.org>
Fri, 06 Jan 2006 13:20:10 +0000
changeset 1234 73676c1f56ee
parent 1196 b81f54c3963f
child 1312 c9b51268668f
permissions -rw-r--r--
For sanity's sake, removed the '&' when passing copy_row array to asm.
     1 /*
     2     SDL - Simple DirectMedia Layer
     3     Copyright (C) 1997-2004 Sam Lantinga
     4 
     5     This library is free software; you can redistribute it and/or
     6     modify it under the terms of the GNU Library General Public
     7     License as published by the Free Software Foundation; either
     8     version 2 of the License, or (at your option) any later version.
     9 
    10     This library is distributed in the hope that it will be useful,
    11     but WITHOUT ANY WARRANTY; without even the implied warranty of
    12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    13     Library General Public License for more details.
    14 
    15     You should have received a copy of the GNU Library General Public
    16     License along with this library; if not, write to the Free
    17     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
    18 
    19     Sam Lantinga
    20     slouken@libsdl.org
    21 */
    22 
    23 #ifdef SAVE_RCSID
    24 static char rcsid =
    25  "@(#) $Id$";
    26 #endif
    27 
    28 #include <stdio.h>
    29 #include <stdlib.h>
    30 #include <string.h>
    31 
    32 #include "SDL_error.h"
    33 #include "SDL_video.h"
    34 #include "SDL_sysvideo.h"
    35 #include "SDL_blit.h"
    36 #include "SDL_RLEaccel_c.h"
    37 #include "SDL_pixels_c.h"
    38 #include "SDL_memops.h"
    39 
    40 #if (defined(i386) || defined(__x86_64__)) && defined(__GNUC__) && defined(USE_ASMBLIT)
    41 #define MMX_ASMBLIT
    42 #endif
    43 
    44 #if defined(MMX_ASMBLIT)
    45 #include "SDL_cpuinfo.h"
    46 #include "mmx.h"
    47 #endif
    48 
    49 /* The general purpose software blit routine */
    50 static int SDL_SoftBlit(SDL_Surface *src, SDL_Rect *srcrect,
    51 			SDL_Surface *dst, SDL_Rect *dstrect)
    52 {
    53 	int okay;
    54 	int src_locked;
    55 	int dst_locked;
    56 
    57 	/* Everything is okay at the beginning...  */
    58 	okay = 1;
    59 
    60 	/* Lock the destination if it's in hardware */
    61 	dst_locked = 0;
    62 	if ( SDL_MUSTLOCK(dst) ) {
    63 		if ( SDL_LockSurface(dst) < 0 ) {
    64 			okay = 0;
    65 		} else {
    66 			dst_locked = 1;
    67 		}
    68 	}
    69 	/* Lock the source if it's in hardware */
    70 	src_locked = 0;
    71 	if ( SDL_MUSTLOCK(src) ) {
    72 		if ( SDL_LockSurface(src) < 0 ) {
    73 			okay = 0;
    74 		} else {
    75 			src_locked = 1;
    76 		}
    77 	}
    78 
    79 	/* Set up source and destination buffer pointers, and BLIT! */
    80 	if ( okay  && srcrect->w && srcrect->h ) {
    81 		SDL_BlitInfo info;
    82 		SDL_loblit RunBlit;
    83 
    84 		/* Set up the blit information */
    85 		info.s_pixels = (Uint8 *)src->pixels +
    86 				(Uint16)srcrect->y*src->pitch +
    87 				(Uint16)srcrect->x*src->format->BytesPerPixel;
    88 		info.s_width = srcrect->w;
    89 		info.s_height = srcrect->h;
    90 		info.s_skip=src->pitch-info.s_width*src->format->BytesPerPixel;
    91 		info.d_pixels = (Uint8 *)dst->pixels +
    92 				(Uint16)dstrect->y*dst->pitch +
    93 				(Uint16)dstrect->x*dst->format->BytesPerPixel;
    94 		info.d_width = dstrect->w;
    95 		info.d_height = dstrect->h;
    96 		info.d_skip=dst->pitch-info.d_width*dst->format->BytesPerPixel;
    97 		info.aux_data = src->map->sw_data->aux_data;
    98 		info.src = src->format;
    99 		info.table = src->map->table;
   100 		info.dst = dst->format;
   101 		RunBlit = src->map->sw_data->blit;
   102 
   103 		/* Run the actual software blit */
   104 		RunBlit(&info);
   105 	}
   106 
   107 	/* We need to unlock the surfaces if they're locked */
   108 	if ( dst_locked ) {
   109 		SDL_UnlockSurface(dst);
   110 	}
   111 	if ( src_locked ) {
   112 		SDL_UnlockSurface(src);
   113 	}
   114 	/* Blit is done! */
   115 	return(okay ? 0 : -1);
   116 }
   117 
   118 #ifdef MMX_ASMBLIT
   119 static __inline__ void SDL_memcpyMMX(Uint8 *to, const Uint8 *from, int len)
   120 {
   121 	int i;
   122 
   123 	for(i=0; i<len/8; i++) {
   124 		__asm__ __volatile__ (
   125 		"	movq (%0), %%mm0\n"
   126 		"	movq %%mm0, (%1)\n"
   127 		: : "r" (from), "r" (to) : "memory");
   128 		from+=8;
   129 		to+=8;
   130 	}
   131 	if (len&7)
   132 		SDL_memcpy(to, from, len&7);
   133 }
   134 
   135 static __inline__ void SDL_memcpySSE(Uint8 *to, const Uint8 *from, int len)
   136 {
   137 	int i;
   138 
   139 	__asm__ __volatile__ (
   140 	"	prefetchnta (%0)\n"
   141 	"	prefetchnta 64(%0)\n"
   142 	"	prefetchnta 128(%0)\n"
   143 	"	prefetchnta 192(%0)\n"
   144 	: : "r" (from) );
   145 
   146 	for(i=0; i<len/8; i++) {
   147 		__asm__ __volatile__ (
   148 		"	prefetchnta 256(%0)\n"
   149 		"	movq (%0), %%mm0\n"
   150 		"	movntq %%mm0, (%1)\n"
   151 		: : "r" (from), "r" (to) : "memory");
   152 		from+=8;
   153 		to+=8;
   154 	}
   155 	if (len&7)
   156 		SDL_memcpy(to, from, len&7);
   157 }
   158 #endif
   159 
   160 static void SDL_BlitCopy(SDL_BlitInfo *info)
   161 {
   162 	Uint8 *src, *dst;
   163 	int w, h;
   164 	int srcskip, dstskip;
   165 
   166 	w = info->d_width*info->dst->BytesPerPixel;
   167 	h = info->d_height;
   168 	src = info->s_pixels;
   169 	dst = info->d_pixels;
   170 	srcskip = w+info->s_skip;
   171 	dstskip = w+info->d_skip;
   172 #ifdef MMX_ASMBLIT
   173 	if(SDL_HasSSE())
   174 	{
   175 		while ( h-- ) {
   176 			SDL_memcpySSE(dst, src, w);
   177 			src += srcskip;
   178 			dst += dstskip;
   179 		}
   180 		__asm__ __volatile__ (
   181 		"	emms\n"
   182 		::);
   183 	}
   184 	else
   185 	if(SDL_HasMMX())
   186 	{
   187 		while ( h-- ) {
   188 			SDL_memcpyMMX(dst, src, w);
   189 			src += srcskip;
   190 			dst += dstskip;
   191 		}
   192 		__asm__ __volatile__ (
   193 		"	emms\n"
   194 		::);
   195 	}
   196 	else
   197 #endif
   198 	while ( h-- ) {
   199 		SDL_memcpy(dst, src, w);
   200 		src += srcskip;
   201 		dst += dstskip;
   202 	}
   203 }
   204 
   205 static void SDL_BlitCopyOverlap(SDL_BlitInfo *info)
   206 {
   207 	Uint8 *src, *dst;
   208 	int w, h;
   209 	int srcskip, dstskip;
   210 
   211 	w = info->d_width*info->dst->BytesPerPixel;
   212 	h = info->d_height;
   213 	src = info->s_pixels;
   214 	dst = info->d_pixels;
   215 	srcskip = w+info->s_skip;
   216 	dstskip = w+info->d_skip;
   217 	if ( dst < src ) {
   218 		while ( h-- ) {
   219 			SDL_memcpy(dst, src, w);
   220 			src += srcskip;
   221 			dst += dstskip;
   222 		}
   223 	} else {
   224 		src += ((h-1) * srcskip);
   225 		dst += ((h-1) * dstskip);
   226 		while ( h-- ) {
   227 			SDL_revcpy(dst, src, w);
   228 			src -= srcskip;
   229 			dst -= dstskip;
   230 		}
   231 	}
   232 }
   233 
   234 /* Figure out which of many blit routines to set up on a surface */
   235 int SDL_CalculateBlit(SDL_Surface *surface)
   236 {
   237 	int blit_index;
   238 
   239 	/* Clean everything out to start */
   240 	if ( (surface->flags & SDL_RLEACCEL) == SDL_RLEACCEL ) {
   241 		SDL_UnRLESurface(surface, 1);
   242 	}
   243 	surface->map->sw_blit = NULL;
   244 
   245 	/* Figure out if an accelerated hardware blit is possible */
   246 	surface->flags &= ~SDL_HWACCEL;
   247 	if ( surface->map->identity ) {
   248 		int hw_blit_ok;
   249 
   250 		if ( (surface->flags & SDL_HWSURFACE) == SDL_HWSURFACE ) {
   251 			/* We only support accelerated blitting to hardware */
   252 			if ( surface->map->dst->flags & SDL_HWSURFACE ) {
   253 				hw_blit_ok = current_video->info.blit_hw;
   254 			} else {
   255 				hw_blit_ok = 0;
   256 			}
   257 			if (hw_blit_ok && (surface->flags & SDL_SRCCOLORKEY)) {
   258 				hw_blit_ok = current_video->info.blit_hw_CC;
   259 			}
   260 			if ( hw_blit_ok && (surface->flags & SDL_SRCALPHA) ) {
   261 				hw_blit_ok = current_video->info.blit_hw_A;
   262 			}
   263 		} else {
   264 			/* We only support accelerated blitting to hardware */
   265 			if ( surface->map->dst->flags & SDL_HWSURFACE ) {
   266 				hw_blit_ok = current_video->info.blit_sw;
   267 			} else {
   268 				hw_blit_ok = 0;
   269 			}
   270 			if (hw_blit_ok && (surface->flags & SDL_SRCCOLORKEY)) {
   271 				hw_blit_ok = current_video->info.blit_sw_CC;
   272 			}
   273 			if ( hw_blit_ok && (surface->flags & SDL_SRCALPHA) ) {
   274 				hw_blit_ok = current_video->info.blit_sw_A;
   275 			}
   276 		}
   277 		if ( hw_blit_ok ) {
   278 			SDL_VideoDevice *video = current_video;
   279 			SDL_VideoDevice *this  = current_video;
   280 			video->CheckHWBlit(this, surface, surface->map->dst);
   281 		}
   282 	}
   283 	
   284 	/* if an alpha pixel format is specified, we can accelerate alpha blits */
   285 	if (((surface->flags & SDL_HWSURFACE) == SDL_HWSURFACE )&&(current_video->displayformatalphapixel)) 
   286 	{
   287 		if ( (surface->flags & SDL_SRCALPHA) ) 
   288 			if ( current_video->info.blit_hw_A ) {
   289 				SDL_VideoDevice *video = current_video;
   290 				SDL_VideoDevice *this  = current_video;
   291 				video->CheckHWBlit(this, surface, surface->map->dst);
   292 			}
   293 	}
   294 
   295 	/* Get the blit function index, based on surface mode */
   296 	/* { 0 = nothing, 1 = colorkey, 2 = alpha, 3 = colorkey+alpha } */
   297 	blit_index = 0;
   298 	blit_index |= (!!(surface->flags & SDL_SRCCOLORKEY))      << 0;
   299 	if ( surface->flags & SDL_SRCALPHA
   300 	     && (surface->format->alpha != SDL_ALPHA_OPAQUE
   301 		 || surface->format->Amask) ) {
   302 	        blit_index |= 2;
   303 	}
   304 
   305 	/* Check for special "identity" case -- copy blit */
   306 	if ( surface->map->identity && blit_index == 0 ) {
   307 	        surface->map->sw_data->blit = SDL_BlitCopy;
   308 
   309 		/* Handle overlapping blits on the same surface */
   310 		if ( surface == surface->map->dst ) {
   311 		        surface->map->sw_data->blit = SDL_BlitCopyOverlap;
   312 		}
   313 	} else {
   314 		if ( surface->format->BitsPerPixel < 8 ) {
   315 			surface->map->sw_data->blit =
   316 			    SDL_CalculateBlit0(surface, blit_index);
   317 		} else {
   318 			switch ( surface->format->BytesPerPixel ) {
   319 			    case 1:
   320 				surface->map->sw_data->blit =
   321 				    SDL_CalculateBlit1(surface, blit_index);
   322 				break;
   323 			    case 2:
   324 			    case 3:
   325 			    case 4:
   326 				surface->map->sw_data->blit =
   327 				    SDL_CalculateBlitN(surface, blit_index);
   328 				break;
   329 			    default:
   330 				surface->map->sw_data->blit = NULL;
   331 				break;
   332 			}
   333 		}
   334 	}
   335 	/* Make sure we have a blit function */
   336 	if ( surface->map->sw_data->blit == NULL ) {
   337 		SDL_InvalidateMap(surface->map);
   338 		SDL_SetError("Blit combination not supported");
   339 		return(-1);
   340 	}
   341 
   342 	/* Choose software blitting function */
   343 	if(surface->flags & SDL_RLEACCELOK
   344 	   && (surface->flags & SDL_HWACCEL) != SDL_HWACCEL) {
   345 
   346 	        if(surface->map->identity
   347 		   && (blit_index == 1
   348 		       || (blit_index == 3 && !surface->format->Amask))) {
   349 		        if ( SDL_RLESurface(surface) == 0 )
   350 			        surface->map->sw_blit = SDL_RLEBlit;
   351 		} else if(blit_index == 2 && surface->format->Amask) {
   352 		        if ( SDL_RLESurface(surface) == 0 )
   353 			        surface->map->sw_blit = SDL_RLEAlphaBlit;
   354 		}
   355 	}
   356 	
   357 	if ( surface->map->sw_blit == NULL ) {
   358 		surface->map->sw_blit = SDL_SoftBlit;
   359 	}
   360 	return(0);
   361 }
   362