Mercurial > sdl-ios-xcode
view src/video/SDL_blit.c @ 1240:3b8a43c428bb
From Bug #36:
There are a couple of issues with the selection of Altivec alpha-blitting
routines in CalculateAlphaBlit() in src/video/SDL_Blit_A.c.
1) There's no check for the presence of Altivec when checking if the
Blit32to565PixelAlphaAltivec() routine can be selected.
2) Altivec cannot be used in video memory, and there's no check if the
destination surface is a hardware surface. (Alpha-blitting to a hardware
surface with GPU support is a bad idea, but somebody's bound to do it anyway.)
Patch to fix these attached.
author | Ryan C. Gordon <icculus@icculus.org> |
---|---|
date | Sun, 08 Jan 2006 21:18:15 +0000 |
parents | b81f54c3963f |
children | c9b51268668f |
line wrap: on
line source
/* SDL - Simple DirectMedia Layer Copyright (C) 1997-2004 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 <stdlib.h> #include <string.h> #include "SDL_error.h" #include "SDL_video.h" #include "SDL_sysvideo.h" #include "SDL_blit.h" #include "SDL_RLEaccel_c.h" #include "SDL_pixels_c.h" #include "SDL_memops.h" #if (defined(i386) || defined(__x86_64__)) && defined(__GNUC__) && defined(USE_ASMBLIT) #define MMX_ASMBLIT #endif #if defined(MMX_ASMBLIT) #include "SDL_cpuinfo.h" #include "mmx.h" #endif /* The general purpose software blit routine */ static int SDL_SoftBlit(SDL_Surface *src, SDL_Rect *srcrect, SDL_Surface *dst, SDL_Rect *dstrect) { int okay; int src_locked; int dst_locked; /* Everything is okay at the beginning... */ okay = 1; /* Lock the destination if it's in hardware */ dst_locked = 0; if ( SDL_MUSTLOCK(dst) ) { if ( SDL_LockSurface(dst) < 0 ) { okay = 0; } else { dst_locked = 1; } } /* Lock the source if it's in hardware */ src_locked = 0; if ( SDL_MUSTLOCK(src) ) { if ( SDL_LockSurface(src) < 0 ) { okay = 0; } else { src_locked = 1; } } /* Set up source and destination buffer pointers, and BLIT! */ if ( okay && srcrect->w && srcrect->h ) { SDL_BlitInfo info; SDL_loblit RunBlit; /* Set up the blit information */ info.s_pixels = (Uint8 *)src->pixels + (Uint16)srcrect->y*src->pitch + (Uint16)srcrect->x*src->format->BytesPerPixel; info.s_width = srcrect->w; info.s_height = srcrect->h; info.s_skip=src->pitch-info.s_width*src->format->BytesPerPixel; info.d_pixels = (Uint8 *)dst->pixels + (Uint16)dstrect->y*dst->pitch + (Uint16)dstrect->x*dst->format->BytesPerPixel; info.d_width = dstrect->w; info.d_height = dstrect->h; info.d_skip=dst->pitch-info.d_width*dst->format->BytesPerPixel; info.aux_data = src->map->sw_data->aux_data; info.src = src->format; info.table = src->map->table; info.dst = dst->format; RunBlit = src->map->sw_data->blit; /* Run the actual software blit */ RunBlit(&info); } /* We need to unlock the surfaces if they're locked */ if ( dst_locked ) { SDL_UnlockSurface(dst); } if ( src_locked ) { SDL_UnlockSurface(src); } /* Blit is done! */ return(okay ? 0 : -1); } #ifdef MMX_ASMBLIT static __inline__ void SDL_memcpyMMX(Uint8 *to, const Uint8 *from, int len) { int i; for(i=0; i<len/8; i++) { __asm__ __volatile__ ( " movq (%0), %%mm0\n" " movq %%mm0, (%1)\n" : : "r" (from), "r" (to) : "memory"); from+=8; to+=8; } if (len&7) SDL_memcpy(to, from, len&7); } static __inline__ void SDL_memcpySSE(Uint8 *to, const Uint8 *from, int len) { int i; __asm__ __volatile__ ( " prefetchnta (%0)\n" " prefetchnta 64(%0)\n" " prefetchnta 128(%0)\n" " prefetchnta 192(%0)\n" : : "r" (from) ); for(i=0; i<len/8; i++) { __asm__ __volatile__ ( " prefetchnta 256(%0)\n" " movq (%0), %%mm0\n" " movntq %%mm0, (%1)\n" : : "r" (from), "r" (to) : "memory"); from+=8; to+=8; } if (len&7) SDL_memcpy(to, from, len&7); } #endif static void SDL_BlitCopy(SDL_BlitInfo *info) { Uint8 *src, *dst; int w, h; int srcskip, dstskip; w = info->d_width*info->dst->BytesPerPixel; h = info->d_height; src = info->s_pixels; dst = info->d_pixels; srcskip = w+info->s_skip; dstskip = w+info->d_skip; #ifdef MMX_ASMBLIT if(SDL_HasSSE()) { while ( h-- ) { SDL_memcpySSE(dst, src, w); src += srcskip; dst += dstskip; } __asm__ __volatile__ ( " emms\n" ::); } else if(SDL_HasMMX()) { while ( h-- ) { SDL_memcpyMMX(dst, src, w); src += srcskip; dst += dstskip; } __asm__ __volatile__ ( " emms\n" ::); } else #endif while ( h-- ) { SDL_memcpy(dst, src, w); src += srcskip; dst += dstskip; } } static void SDL_BlitCopyOverlap(SDL_BlitInfo *info) { Uint8 *src, *dst; int w, h; int srcskip, dstskip; w = info->d_width*info->dst->BytesPerPixel; h = info->d_height; src = info->s_pixels; dst = info->d_pixels; srcskip = w+info->s_skip; dstskip = w+info->d_skip; if ( dst < src ) { while ( h-- ) { SDL_memcpy(dst, src, w); src += srcskip; dst += dstskip; } } else { src += ((h-1) * srcskip); dst += ((h-1) * dstskip); while ( h-- ) { SDL_revcpy(dst, src, w); src -= srcskip; dst -= dstskip; } } } /* Figure out which of many blit routines to set up on a surface */ int SDL_CalculateBlit(SDL_Surface *surface) { int blit_index; /* Clean everything out to start */ if ( (surface->flags & SDL_RLEACCEL) == SDL_RLEACCEL ) { SDL_UnRLESurface(surface, 1); } surface->map->sw_blit = NULL; /* Figure out if an accelerated hardware blit is possible */ surface->flags &= ~SDL_HWACCEL; if ( surface->map->identity ) { int hw_blit_ok; if ( (surface->flags & SDL_HWSURFACE) == SDL_HWSURFACE ) { /* We only support accelerated blitting to hardware */ if ( surface->map->dst->flags & SDL_HWSURFACE ) { hw_blit_ok = current_video->info.blit_hw; } else { hw_blit_ok = 0; } if (hw_blit_ok && (surface->flags & SDL_SRCCOLORKEY)) { hw_blit_ok = current_video->info.blit_hw_CC; } if ( hw_blit_ok && (surface->flags & SDL_SRCALPHA) ) { hw_blit_ok = current_video->info.blit_hw_A; } } else { /* We only support accelerated blitting to hardware */ if ( surface->map->dst->flags & SDL_HWSURFACE ) { hw_blit_ok = current_video->info.blit_sw; } else { hw_blit_ok = 0; } if (hw_blit_ok && (surface->flags & SDL_SRCCOLORKEY)) { hw_blit_ok = current_video->info.blit_sw_CC; } if ( hw_blit_ok && (surface->flags & SDL_SRCALPHA) ) { hw_blit_ok = current_video->info.blit_sw_A; } } if ( hw_blit_ok ) { SDL_VideoDevice *video = current_video; SDL_VideoDevice *this = current_video; video->CheckHWBlit(this, surface, surface->map->dst); } } /* if an alpha pixel format is specified, we can accelerate alpha blits */ if (((surface->flags & SDL_HWSURFACE) == SDL_HWSURFACE )&&(current_video->displayformatalphapixel)) { if ( (surface->flags & SDL_SRCALPHA) ) if ( current_video->info.blit_hw_A ) { SDL_VideoDevice *video = current_video; SDL_VideoDevice *this = current_video; video->CheckHWBlit(this, surface, surface->map->dst); } } /* Get the blit function index, based on surface mode */ /* { 0 = nothing, 1 = colorkey, 2 = alpha, 3 = colorkey+alpha } */ blit_index = 0; blit_index |= (!!(surface->flags & SDL_SRCCOLORKEY)) << 0; if ( surface->flags & SDL_SRCALPHA && (surface->format->alpha != SDL_ALPHA_OPAQUE || surface->format->Amask) ) { blit_index |= 2; } /* Check for special "identity" case -- copy blit */ if ( surface->map->identity && blit_index == 0 ) { surface->map->sw_data->blit = SDL_BlitCopy; /* Handle overlapping blits on the same surface */ if ( surface == surface->map->dst ) { surface->map->sw_data->blit = SDL_BlitCopyOverlap; } } else { if ( surface->format->BitsPerPixel < 8 ) { surface->map->sw_data->blit = SDL_CalculateBlit0(surface, blit_index); } else { switch ( surface->format->BytesPerPixel ) { case 1: surface->map->sw_data->blit = SDL_CalculateBlit1(surface, blit_index); break; case 2: case 3: case 4: surface->map->sw_data->blit = SDL_CalculateBlitN(surface, blit_index); break; default: surface->map->sw_data->blit = NULL; break; } } } /* Make sure we have a blit function */ if ( surface->map->sw_data->blit == NULL ) { SDL_InvalidateMap(surface->map); SDL_SetError("Blit combination not supported"); return(-1); } /* Choose software blitting function */ if(surface->flags & SDL_RLEACCELOK && (surface->flags & SDL_HWACCEL) != SDL_HWACCEL) { if(surface->map->identity && (blit_index == 1 || (blit_index == 3 && !surface->format->Amask))) { if ( SDL_RLESurface(surface) == 0 ) surface->map->sw_blit = SDL_RLEBlit; } else if(blit_index == 2 && surface->format->Amask) { if ( SDL_RLESurface(surface) == 0 ) surface->map->sw_blit = SDL_RLEAlphaBlit; } } if ( surface->map->sw_blit == NULL ) { surface->map->sw_blit = SDL_SoftBlit; } return(0); }