--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/video/SDL_blit.c	Thu Apr 26 16:45:43 2001 +0000
@@ -0,0 +1,294 @@
+/*
+    SDL - Simple DirectMedia Layer
+    Copyright (C) 1997, 1998, 1999, 2000, 2001  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@devolution.com
+*/
+
+#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"
+
+/* 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 ( dst->flags & (SDL_HWSURFACE|SDL_ASYNCBLIT) ) {
+		SDL_VideoDevice *video = current_video;
+		SDL_VideoDevice *this  = current_video;
+		if ( video->LockHWSurface(this, dst) < 0 ) {
+			okay = 0;
+		} else {
+			dst_locked = 1;
+		}
+	}
+	/* Lock the source if it's in hardware */
+	src_locked = 0;
+	if ( src->flags & (SDL_HWSURFACE|SDL_ASYNCBLIT) ) {
+		SDL_VideoDevice *video = current_video;
+		SDL_VideoDevice *this  = current_video;
+		if ( video->LockHWSurface(this, src) < 0 ) {
+			okay = 0;
+		} else {
+			src_locked = 1;
+		}
+	}
+
+	/* Unencode the destination if it's RLE encoded */
+	if ( dst->flags & SDL_RLEACCEL ) {
+		SDL_UnRLESurface(dst, 1);
+		dst->flags |= SDL_RLEACCEL;	/* save accel'd state */
+	}
+
+	/* 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 + src->offset +
+				(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 + dst->offset +
+				(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);
+	}
+
+	/* Re-encode the destination if it's RLE encoded */
+	if ( dst->flags & SDL_RLEACCEL ) {
+	        dst->flags &= ~SDL_RLEACCEL; /* stop lying */
+		SDL_RLESurface(dst);
+	}
+
+	/* We need to unlock the surfaces if they're locked */
+	if ( dst_locked ) {
+		SDL_VideoDevice *video = current_video;
+		SDL_VideoDevice *this  = current_video;
+		video->UnlockHWSurface(this, dst);
+	} else
+	if ( src_locked ) {
+		SDL_VideoDevice *video = current_video;
+		SDL_VideoDevice *this  = current_video;
+		video->UnlockHWSurface(this, src);
+	}
+	/* Blit is done! */
+	return(okay ? 0 : -1);
+}
+
+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;
+	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);
+		}
+	}
+
+	/* 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);
+}
+