src/video/SDL_blit.c
author Sam Lantinga <slouken@libsdl.org>
Tue, 21 Feb 2006 08:46:50 +0000
changeset 1402 d910939febfa
parent 1361 19418e4422cb
child 1658 e49147870aac
child 1895 c121d94672cb
child 3909 6832b00d3594
permissions -rw-r--r--
Use consistent identifiers for the various platforms we support.
Make sure every source file includes SDL_config.h, so the proper system
headers are chosen.
     1 /*
     2     SDL - Simple DirectMedia Layer
     3     Copyright (C) 1997-2006 Sam Lantinga
     4 
     5     This library is free software; you can redistribute it and/or
     6     modify it under the terms of the GNU Lesser General Public
     7     License as published by the Free Software Foundation; either
     8     version 2.1 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     Lesser General Public License for more details.
    14 
    15     You should have received a copy of the GNU Lesser General Public
    16     License along with this library; if not, write to the Free Software
    17     Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
    18 
    19     Sam Lantinga
    20     slouken@libsdl.org
    21 */
    22 #include "SDL_config.h"
    23 
    24 #include "SDL_video.h"
    25 #include "SDL_sysvideo.h"
    26 #include "SDL_blit.h"
    27 #include "SDL_RLEaccel_c.h"
    28 #include "SDL_pixels_c.h"
    29 
    30 #if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__)) && SDL_ASSEMBLY_ROUTINES
    31 #define MMX_ASMBLIT
    32 #endif
    33 
    34 #if defined(MMX_ASMBLIT)
    35 #include "SDL_cpuinfo.h"
    36 #include "mmx.h"
    37 #endif
    38 
    39 /* The general purpose software blit routine */
    40 static int SDL_SoftBlit(SDL_Surface *src, SDL_Rect *srcrect,
    41 			SDL_Surface *dst, SDL_Rect *dstrect)
    42 {
    43 	int okay;
    44 	int src_locked;
    45 	int dst_locked;
    46 
    47 	/* Everything is okay at the beginning...  */
    48 	okay = 1;
    49 
    50 	/* Lock the destination if it's in hardware */
    51 	dst_locked = 0;
    52 	if ( SDL_MUSTLOCK(dst) ) {
    53 		if ( SDL_LockSurface(dst) < 0 ) {
    54 			okay = 0;
    55 		} else {
    56 			dst_locked = 1;
    57 		}
    58 	}
    59 	/* Lock the source if it's in hardware */
    60 	src_locked = 0;
    61 	if ( SDL_MUSTLOCK(src) ) {
    62 		if ( SDL_LockSurface(src) < 0 ) {
    63 			okay = 0;
    64 		} else {
    65 			src_locked = 1;
    66 		}
    67 	}
    68 
    69 	/* Set up source and destination buffer pointers, and BLIT! */
    70 	if ( okay  && srcrect->w && srcrect->h ) {
    71 		SDL_BlitInfo info;
    72 		SDL_loblit RunBlit;
    73 
    74 		/* Set up the blit information */
    75 		info.s_pixels = (Uint8 *)src->pixels +
    76 				(Uint16)srcrect->y*src->pitch +
    77 				(Uint16)srcrect->x*src->format->BytesPerPixel;
    78 		info.s_width = srcrect->w;
    79 		info.s_height = srcrect->h;
    80 		info.s_skip=src->pitch-info.s_width*src->format->BytesPerPixel;
    81 		info.d_pixels = (Uint8 *)dst->pixels +
    82 				(Uint16)dstrect->y*dst->pitch +
    83 				(Uint16)dstrect->x*dst->format->BytesPerPixel;
    84 		info.d_width = dstrect->w;
    85 		info.d_height = dstrect->h;
    86 		info.d_skip=dst->pitch-info.d_width*dst->format->BytesPerPixel;
    87 		info.aux_data = src->map->sw_data->aux_data;
    88 		info.src = src->format;
    89 		info.table = src->map->table;
    90 		info.dst = dst->format;
    91 		RunBlit = src->map->sw_data->blit;
    92 
    93 		/* Run the actual software blit */
    94 		RunBlit(&info);
    95 	}
    96 
    97 	/* We need to unlock the surfaces if they're locked */
    98 	if ( dst_locked ) {
    99 		SDL_UnlockSurface(dst);
   100 	}
   101 	if ( src_locked ) {
   102 		SDL_UnlockSurface(src);
   103 	}
   104 	/* Blit is done! */
   105 	return(okay ? 0 : -1);
   106 }
   107 
   108 #ifdef MMX_ASMBLIT
   109 static __inline__ void SDL_memcpyMMX(Uint8 *to, const Uint8 *from, int len)
   110 {
   111 	int i;
   112 
   113 	for(i=0; i<len/8; i++) {
   114 		__asm__ __volatile__ (
   115 		"	movq (%0), %%mm0\n"
   116 		"	movq %%mm0, (%1)\n"
   117 		: : "r" (from), "r" (to) : "memory");
   118 		from+=8;
   119 		to+=8;
   120 	}
   121 	if (len&7)
   122 		SDL_memcpy(to, from, len&7);
   123 }
   124 
   125 static __inline__ void SDL_memcpySSE(Uint8 *to, const Uint8 *from, int len)
   126 {
   127 	int i;
   128 
   129 	__asm__ __volatile__ (
   130 	"	prefetchnta (%0)\n"
   131 	"	prefetchnta 64(%0)\n"
   132 	"	prefetchnta 128(%0)\n"
   133 	"	prefetchnta 192(%0)\n"
   134 	: : "r" (from) );
   135 
   136 	for(i=0; i<len/8; i++) {
   137 		__asm__ __volatile__ (
   138 		"	prefetchnta 256(%0)\n"
   139 		"	movq (%0), %%mm0\n"
   140 		"	movntq %%mm0, (%1)\n"
   141 		: : "r" (from), "r" (to) : "memory");
   142 		from+=8;
   143 		to+=8;
   144 	}
   145 	if (len&7)
   146 		SDL_memcpy(to, from, len&7);
   147 }
   148 #endif
   149 
   150 static void SDL_BlitCopy(SDL_BlitInfo *info)
   151 {
   152 	Uint8 *src, *dst;
   153 	int w, h;
   154 	int srcskip, dstskip;
   155 
   156 	w = info->d_width*info->dst->BytesPerPixel;
   157 	h = info->d_height;
   158 	src = info->s_pixels;
   159 	dst = info->d_pixels;
   160 	srcskip = w+info->s_skip;
   161 	dstskip = w+info->d_skip;
   162 #ifdef MMX_ASMBLIT
   163 	if(SDL_HasSSE())
   164 	{
   165 		while ( h-- ) {
   166 			SDL_memcpySSE(dst, src, w);
   167 			src += srcskip;
   168 			dst += dstskip;
   169 		}
   170 		__asm__ __volatile__ (
   171 		"	emms\n"
   172 		::);
   173 	}
   174 	else
   175 	if(SDL_HasMMX())
   176 	{
   177 		while ( h-- ) {
   178 			SDL_memcpyMMX(dst, src, w);
   179 			src += srcskip;
   180 			dst += dstskip;
   181 		}
   182 		__asm__ __volatile__ (
   183 		"	emms\n"
   184 		::);
   185 	}
   186 	else
   187 #endif
   188 	while ( h-- ) {
   189 		SDL_memcpy(dst, src, w);
   190 		src += srcskip;
   191 		dst += dstskip;
   192 	}
   193 }
   194 
   195 static void SDL_BlitCopyOverlap(SDL_BlitInfo *info)
   196 {
   197 	Uint8 *src, *dst;
   198 	int w, h;
   199 	int srcskip, dstskip;
   200 
   201 	w = info->d_width*info->dst->BytesPerPixel;
   202 	h = info->d_height;
   203 	src = info->s_pixels;
   204 	dst = info->d_pixels;
   205 	srcskip = w+info->s_skip;
   206 	dstskip = w+info->d_skip;
   207 	if ( dst < src ) {
   208 		while ( h-- ) {
   209 			SDL_memcpy(dst, src, w);
   210 			src += srcskip;
   211 			dst += dstskip;
   212 		}
   213 	} else {
   214 		src += ((h-1) * srcskip);
   215 		dst += ((h-1) * dstskip);
   216 		while ( h-- ) {
   217 			SDL_revcpy(dst, src, w);
   218 			src -= srcskip;
   219 			dst -= dstskip;
   220 		}
   221 	}
   222 }
   223 
   224 /* Figure out which of many blit routines to set up on a surface */
   225 int SDL_CalculateBlit(SDL_Surface *surface)
   226 {
   227 	int blit_index;
   228 
   229 	/* Clean everything out to start */
   230 	if ( (surface->flags & SDL_RLEACCEL) == SDL_RLEACCEL ) {
   231 		SDL_UnRLESurface(surface, 1);
   232 	}
   233 	surface->map->sw_blit = NULL;
   234 
   235 	/* Figure out if an accelerated hardware blit is possible */
   236 	surface->flags &= ~SDL_HWACCEL;
   237 	if ( surface->map->identity ) {
   238 		int hw_blit_ok;
   239 
   240 		if ( (surface->flags & SDL_HWSURFACE) == SDL_HWSURFACE ) {
   241 			/* We only support accelerated blitting to hardware */
   242 			if ( surface->map->dst->flags & SDL_HWSURFACE ) {
   243 				hw_blit_ok = current_video->info.blit_hw;
   244 			} else {
   245 				hw_blit_ok = 0;
   246 			}
   247 			if (hw_blit_ok && (surface->flags & SDL_SRCCOLORKEY)) {
   248 				hw_blit_ok = current_video->info.blit_hw_CC;
   249 			}
   250 			if ( hw_blit_ok && (surface->flags & SDL_SRCALPHA) ) {
   251 				hw_blit_ok = current_video->info.blit_hw_A;
   252 			}
   253 		} else {
   254 			/* We only support accelerated blitting to hardware */
   255 			if ( surface->map->dst->flags & SDL_HWSURFACE ) {
   256 				hw_blit_ok = current_video->info.blit_sw;
   257 			} else {
   258 				hw_blit_ok = 0;
   259 			}
   260 			if (hw_blit_ok && (surface->flags & SDL_SRCCOLORKEY)) {
   261 				hw_blit_ok = current_video->info.blit_sw_CC;
   262 			}
   263 			if ( hw_blit_ok && (surface->flags & SDL_SRCALPHA) ) {
   264 				hw_blit_ok = current_video->info.blit_sw_A;
   265 			}
   266 		}
   267 		if ( hw_blit_ok ) {
   268 			SDL_VideoDevice *video = current_video;
   269 			SDL_VideoDevice *this  = current_video;
   270 			video->CheckHWBlit(this, surface, surface->map->dst);
   271 		}
   272 	}
   273 	
   274 	/* if an alpha pixel format is specified, we can accelerate alpha blits */
   275 	if (((surface->flags & SDL_HWSURFACE) == SDL_HWSURFACE )&&(current_video->displayformatalphapixel)) 
   276 	{
   277 		if ( (surface->flags & SDL_SRCALPHA) ) 
   278 			if ( current_video->info.blit_hw_A ) {
   279 				SDL_VideoDevice *video = current_video;
   280 				SDL_VideoDevice *this  = current_video;
   281 				video->CheckHWBlit(this, surface, surface->map->dst);
   282 			}
   283 	}
   284 
   285 	/* Get the blit function index, based on surface mode */
   286 	/* { 0 = nothing, 1 = colorkey, 2 = alpha, 3 = colorkey+alpha } */
   287 	blit_index = 0;
   288 	blit_index |= (!!(surface->flags & SDL_SRCCOLORKEY))      << 0;
   289 	if ( surface->flags & SDL_SRCALPHA
   290 	     && (surface->format->alpha != SDL_ALPHA_OPAQUE
   291 		 || surface->format->Amask) ) {
   292 	        blit_index |= 2;
   293 	}
   294 
   295 	/* Check for special "identity" case -- copy blit */
   296 	if ( surface->map->identity && blit_index == 0 ) {
   297 	        surface->map->sw_data->blit = SDL_BlitCopy;
   298 
   299 		/* Handle overlapping blits on the same surface */
   300 		if ( surface == surface->map->dst ) {
   301 		        surface->map->sw_data->blit = SDL_BlitCopyOverlap;
   302 		}
   303 	} else {
   304 		if ( surface->format->BitsPerPixel < 8 ) {
   305 			surface->map->sw_data->blit =
   306 			    SDL_CalculateBlit0(surface, blit_index);
   307 		} else {
   308 			switch ( surface->format->BytesPerPixel ) {
   309 			    case 1:
   310 				surface->map->sw_data->blit =
   311 				    SDL_CalculateBlit1(surface, blit_index);
   312 				break;
   313 			    case 2:
   314 			    case 3:
   315 			    case 4:
   316 				surface->map->sw_data->blit =
   317 				    SDL_CalculateBlitN(surface, blit_index);
   318 				break;
   319 			    default:
   320 				surface->map->sw_data->blit = NULL;
   321 				break;
   322 			}
   323 		}
   324 	}
   325 	/* Make sure we have a blit function */
   326 	if ( surface->map->sw_data->blit == NULL ) {
   327 		SDL_InvalidateMap(surface->map);
   328 		SDL_SetError("Blit combination not supported");
   329 		return(-1);
   330 	}
   331 
   332 	/* Choose software blitting function */
   333 	if(surface->flags & SDL_RLEACCELOK
   334 	   && (surface->flags & SDL_HWACCEL) != SDL_HWACCEL) {
   335 
   336 	        if(surface->map->identity
   337 		   && (blit_index == 1
   338 		       || (blit_index == 3 && !surface->format->Amask))) {
   339 		        if ( SDL_RLESurface(surface) == 0 )
   340 			        surface->map->sw_blit = SDL_RLEBlit;
   341 		} else if(blit_index == 2 && surface->format->Amask) {
   342 		        if ( SDL_RLESurface(surface) == 0 )
   343 			        surface->map->sw_blit = SDL_RLEAlphaBlit;
   344 		}
   345 	}
   346 	
   347 	if ( surface->map->sw_blit == NULL ) {
   348 		surface->map->sw_blit = SDL_SoftBlit;
   349 	}
   350 	return(0);
   351 }
   352