src/video/SDL_blit.c
author Sam Lantinga <slouken@libsdl.org>
Sat, 30 Aug 2003 00:36:20 +0000
changeset 697 8468fc0504f3
parent 689 5bb080d35049
child 739 22dbf364c017
permissions -rw-r--r--
*** empty log message ***
     1 /*
     2     SDL - Simple DirectMedia Layer
     3     Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002  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(__GNUC__) && defined(USE_ASMBLIT)
    41 #include "mmx.h"
    42 /* Function to check the CPU flags */
    43 #define MMX_CPU		0x800000
    44 #define SSE_CPU		0x2000000
    45 #define CPU_Flags()	Hermes_X86_CPU()
    46 #define X86_ASSEMBLER
    47 #define HermesConverterInterface	void
    48 #define HermesClearInterface		void
    49 #define STACKCALL
    50 #include "HeadX86.h"
    51 #endif
    52 
    53 /* The general purpose software blit routine */
    54 static int SDL_SoftBlit(SDL_Surface *src, SDL_Rect *srcrect,
    55 			SDL_Surface *dst, SDL_Rect *dstrect)
    56 {
    57 	int okay;
    58 	int src_locked;
    59 	int dst_locked;
    60 
    61 	/* Everything is okay at the beginning...  */
    62 	okay = 1;
    63 
    64 	/* Lock the destination if it's in hardware */
    65 	dst_locked = 0;
    66 	if ( SDL_MUSTLOCK(dst) ) {
    67 		if ( SDL_LockSurface(dst) < 0 ) {
    68 			okay = 0;
    69 		} else {
    70 			dst_locked = 1;
    71 		}
    72 	}
    73 	/* Lock the source if it's in hardware */
    74 	src_locked = 0;
    75 	if ( SDL_MUSTLOCK(src) ) {
    76 		if ( SDL_LockSurface(src) < 0 ) {
    77 			okay = 0;
    78 		} else {
    79 			src_locked = 1;
    80 		}
    81 	}
    82 
    83 	/* Set up source and destination buffer pointers, and BLIT! */
    84 	if ( okay  && srcrect->w && srcrect->h ) {
    85 		SDL_BlitInfo info;
    86 		SDL_loblit RunBlit;
    87 
    88 		/* Set up the blit information */
    89 		info.s_pixels = (Uint8 *)src->pixels +
    90 				(Uint16)srcrect->y*src->pitch +
    91 				(Uint16)srcrect->x*src->format->BytesPerPixel;
    92 		info.s_width = srcrect->w;
    93 		info.s_height = srcrect->h;
    94 		info.s_skip=src->pitch-info.s_width*src->format->BytesPerPixel;
    95 		info.d_pixels = (Uint8 *)dst->pixels +
    96 				(Uint16)dstrect->y*dst->pitch +
    97 				(Uint16)dstrect->x*dst->format->BytesPerPixel;
    98 		info.d_width = dstrect->w;
    99 		info.d_height = dstrect->h;
   100 		info.d_skip=dst->pitch-info.d_width*dst->format->BytesPerPixel;
   101 		info.aux_data = src->map->sw_data->aux_data;
   102 		info.src = src->format;
   103 		info.table = src->map->table;
   104 		info.dst = dst->format;
   105 		RunBlit = src->map->sw_data->blit;
   106 
   107 		/* Run the actual software blit */
   108 		RunBlit(&info);
   109 	}
   110 
   111 	/* We need to unlock the surfaces if they're locked */
   112 	if ( dst_locked ) {
   113 		SDL_UnlockSurface(dst);
   114 	}
   115 	if ( src_locked ) {
   116 		SDL_UnlockSurface(src);
   117 	}
   118 	/* Blit is done! */
   119 	return(okay ? 0 : -1);
   120 }
   121 
   122 #if defined(i386) && defined(__GNUC__) && defined(USE_ASMBLIT)
   123 void SDL_memcpyMMX(char* to,char* from,int len)
   124 {
   125 	int i;
   126 
   127 	for(i=0; i<len/8; i++) {
   128 		__asm__ __volatile__ (
   129 		"	movq (%0), %%mm0\n"
   130 		"	movq %%mm0, (%1)\n"
   131 		: : "r" (from), "r" (to) : "memory");
   132 		from+=8;
   133 		to+=8;
   134 	}
   135 	if (len&7)
   136 		SDL_memcpy(to, from, len&7);
   137 }
   138 
   139 void SDL_memcpySSE(char* to,char* from,int len)
   140 {
   141 	int i;
   142 
   143 	__asm__ __volatile__ (
   144 	"	prefetchnta (%0)\n"
   145 	"	prefetchnta 64(%0)\n"
   146 	"	prefetchnta 128(%0)\n"
   147 	"	prefetchnta 192(%0)\n"
   148 	: : "r" (from) );
   149 
   150 	for(i=0; i<len/8; i++) {
   151 		__asm__ __volatile__ (
   152 		"	prefetchnta 256(%0)\n"
   153 		"	movq (%0), %%mm0\n"
   154 		"	movntq %%mm0, (%1)\n"
   155 		: : "r" (from), "r" (to) : "memory");
   156 		from+=8;
   157 		to+=8;
   158 	}
   159 	if (len&7)
   160 		SDL_memcpy(to, from, len&7);
   161 }
   162 #endif
   163 
   164 static void SDL_BlitCopy(SDL_BlitInfo *info)
   165 {
   166 	Uint8 *src, *dst;
   167 	int w, h;
   168 	int srcskip, dstskip;
   169 #if defined(i386) && defined(__GNUC__) && defined(USE_ASMBLIT)
   170 	Uint32 f;
   171 #endif
   172 
   173 	w = info->d_width*info->dst->BytesPerPixel;
   174 	h = info->d_height;
   175 	src = info->s_pixels;
   176 	dst = info->d_pixels;
   177 	srcskip = w+info->s_skip;
   178 	dstskip = w+info->d_skip;
   179 #if defined(i386) && defined(__GNUC__) && defined(USE_ASMBLIT)
   180 	f=CPU_Flags();
   181 	if((f&(MMX_CPU|SSE_CPU))==(MMX_CPU|SSE_CPU))
   182 	{
   183 		while ( h-- ) {
   184 			SDL_memcpySSE(dst, src, w);
   185 			src += srcskip;
   186 			dst += dstskip;
   187 		}
   188 		__asm__ __volatile__ (
   189 		"	emms\n"
   190 		::);
   191 	}
   192 	else
   193 	if((f&(MMX_CPU))!=0)
   194 	{
   195 		while ( h-- ) {
   196 			SDL_memcpyMMX(dst, src, w);
   197 			src += srcskip;
   198 			dst += dstskip;
   199 		}
   200 		__asm__ __volatile__ (
   201 		"	emms\n"
   202 		::);
   203 	}
   204 	else
   205 #endif
   206 	while ( h-- ) {
   207 		SDL_memcpy(dst, src, w);
   208 		src += srcskip;
   209 		dst += dstskip;
   210 	}
   211 }
   212 
   213 static void SDL_BlitCopyOverlap(SDL_BlitInfo *info)
   214 {
   215 	Uint8 *src, *dst;
   216 	int w, h;
   217 	int srcskip, dstskip;
   218 
   219 	w = info->d_width*info->dst->BytesPerPixel;
   220 	h = info->d_height;
   221 	src = info->s_pixels;
   222 	dst = info->d_pixels;
   223 	srcskip = w+info->s_skip;
   224 	dstskip = w+info->d_skip;
   225 	if ( dst < src ) {
   226 		while ( h-- ) {
   227 			SDL_memcpy(dst, src, w);
   228 			src += srcskip;
   229 			dst += dstskip;
   230 		}
   231 	} else {
   232 		src += ((h-1) * srcskip);
   233 		dst += ((h-1) * dstskip);
   234 		while ( h-- ) {
   235 			SDL_revcpy(dst, src, w);
   236 			src -= srcskip;
   237 			dst -= dstskip;
   238 		}
   239 	}
   240 }
   241 
   242 /* Figure out which of many blit routines to set up on a surface */
   243 int SDL_CalculateBlit(SDL_Surface *surface)
   244 {
   245 	int blit_index;
   246 
   247 	/* Clean everything out to start */
   248 	if ( (surface->flags & SDL_RLEACCEL) == SDL_RLEACCEL ) {
   249 		SDL_UnRLESurface(surface, 1);
   250 	}
   251 	surface->map->sw_blit = NULL;
   252 
   253 	/* Figure out if an accelerated hardware blit is possible */
   254 	surface->flags &= ~SDL_HWACCEL;
   255 	if ( surface->map->identity ) {
   256 		int hw_blit_ok;
   257 
   258 		if ( (surface->flags & SDL_HWSURFACE) == SDL_HWSURFACE ) {
   259 			/* We only support accelerated blitting to hardware */
   260 			if ( surface->map->dst->flags & SDL_HWSURFACE ) {
   261 				hw_blit_ok = current_video->info.blit_hw;
   262 			} else {
   263 				hw_blit_ok = 0;
   264 			}
   265 			if (hw_blit_ok && (surface->flags & SDL_SRCCOLORKEY)) {
   266 				hw_blit_ok = current_video->info.blit_hw_CC;
   267 			}
   268 			if ( hw_blit_ok && (surface->flags & SDL_SRCALPHA) ) {
   269 				hw_blit_ok = current_video->info.blit_hw_A;
   270 			}
   271 		} else {
   272 			/* We only support accelerated blitting to hardware */
   273 			if ( surface->map->dst->flags & SDL_HWSURFACE ) {
   274 				hw_blit_ok = current_video->info.blit_sw;
   275 			} else {
   276 				hw_blit_ok = 0;
   277 			}
   278 			if (hw_blit_ok && (surface->flags & SDL_SRCCOLORKEY)) {
   279 				hw_blit_ok = current_video->info.blit_sw_CC;
   280 			}
   281 			if ( hw_blit_ok && (surface->flags & SDL_SRCALPHA) ) {
   282 				hw_blit_ok = current_video->info.blit_sw_A;
   283 			}
   284 		}
   285 		if ( hw_blit_ok ) {
   286 			SDL_VideoDevice *video = current_video;
   287 			SDL_VideoDevice *this  = current_video;
   288 			video->CheckHWBlit(this, surface, surface->map->dst);
   289 		}
   290 	}
   291 
   292 	/* Get the blit function index, based on surface mode */
   293 	/* { 0 = nothing, 1 = colorkey, 2 = alpha, 3 = colorkey+alpha } */
   294 	blit_index = 0;
   295 	blit_index |= (!!(surface->flags & SDL_SRCCOLORKEY))      << 0;
   296 	if ( surface->flags & SDL_SRCALPHA
   297 	     && (surface->format->alpha != SDL_ALPHA_OPAQUE
   298 		 || surface->format->Amask) ) {
   299 	        blit_index |= 2;
   300 	}
   301 
   302 	/* Check for special "identity" case -- copy blit */
   303 	if ( surface->map->identity && blit_index == 0 ) {
   304 	        surface->map->sw_data->blit = SDL_BlitCopy;
   305 
   306 		/* Handle overlapping blits on the same surface */
   307 		if ( surface == surface->map->dst ) {
   308 		        surface->map->sw_data->blit = SDL_BlitCopyOverlap;
   309 		}
   310 	} else {
   311 		if ( surface->format->BitsPerPixel < 8 ) {
   312 			surface->map->sw_data->blit =
   313 			    SDL_CalculateBlit0(surface, blit_index);
   314 		} else {
   315 			switch ( surface->format->BytesPerPixel ) {
   316 			    case 1:
   317 				surface->map->sw_data->blit =
   318 				    SDL_CalculateBlit1(surface, blit_index);
   319 				break;
   320 			    case 2:
   321 			    case 3:
   322 			    case 4:
   323 				surface->map->sw_data->blit =
   324 				    SDL_CalculateBlitN(surface, blit_index);
   325 				break;
   326 			    default:
   327 				surface->map->sw_data->blit = NULL;
   328 				break;
   329 			}
   330 		}
   331 	}
   332 	/* Make sure we have a blit function */
   333 	if ( surface->map->sw_data->blit == NULL ) {
   334 		SDL_InvalidateMap(surface->map);
   335 		SDL_SetError("Blit combination not supported");
   336 		return(-1);
   337 	}
   338 
   339 	/* Choose software blitting function */
   340 	if(surface->flags & SDL_RLEACCELOK
   341 	   && (surface->flags & SDL_HWACCEL) != SDL_HWACCEL) {
   342 
   343 	        if(surface->map->identity
   344 		   && (blit_index == 1
   345 		       || (blit_index == 3 && !surface->format->Amask))) {
   346 		        if ( SDL_RLESurface(surface) == 0 )
   347 			        surface->map->sw_blit = SDL_RLEBlit;
   348 		} else if(blit_index == 2 && surface->format->Amask) {
   349 		        if ( SDL_RLESurface(surface) == 0 )
   350 			        surface->map->sw_blit = SDL_RLEAlphaBlit;
   351 		}
   352 	}
   353 	
   354 	if ( surface->map->sw_blit == NULL ) {
   355 		surface->map->sw_blit = SDL_SoftBlit;
   356 	}
   357 	return(0);
   358 }
   359