symbian-qemu-0.9.1-12/libsdl-trunk/src/video/SDL_stretch.c
changeset 1 2fb8b9db1c86
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/symbian-qemu-0.9.1-12/libsdl-trunk/src/video/SDL_stretch.c	Fri Jul 31 15:01:17 2009 +0100
@@ -0,0 +1,349 @@
+/*
+    SDL - Simple DirectMedia Layer
+    Copyright (C) 1997-2006 Sam Lantinga
+
+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Lesser General Public
+    License as published by the Free Software Foundation; either
+    version 2.1 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
+    Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public
+    License along with this library; if not, write to the Free Software
+    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+    Sam Lantinga
+    slouken@libsdl.org
+*/
+#include "SDL_config.h"
+
+/* This a stretch blit implementation based on ideas given to me by
+   Tomasz Cejner - thanks! :)
+
+   April 27, 2000 - Sam Lantinga
+*/
+
+#include "SDL_video.h"
+#include "SDL_blit.h"
+
+/* This isn't ready for general consumption yet - it should be folded
+   into the general blitting mechanism.
+*/
+
+#if ((defined(_MFC_VER) && defined(_M_IX86)/* && !defined(_WIN32_WCE) still needed? */) || \
+     defined(__WATCOMC__) || \
+     (defined(__GNUC__) && defined(__i386__))) && SDL_ASSEMBLY_ROUTINES
+#define USE_ASM_STRETCH
+#endif
+
+#ifdef USE_ASM_STRETCH
+
+#ifdef HAVE_MPROTECT
+#include <sys/types.h>
+#include <sys/mman.h>
+#endif
+#ifdef __GNUC__
+#define PAGE_ALIGNED __attribute__((__aligned__(4096)))
+#else
+#define PAGE_ALIGNED
+#endif
+
+#if defined(_M_IX86) || defined(i386)
+#define PREFIX16	0x66
+#define STORE_BYTE	0xAA
+#define STORE_WORD	0xAB
+#define LOAD_BYTE	0xAC
+#define LOAD_WORD	0xAD
+#define RETURN		0xC3
+#else
+#error Need assembly opcodes for this architecture
+#endif
+
+static unsigned char copy_row[4096] PAGE_ALIGNED;
+
+static int generate_rowbytes(int src_w, int dst_w, int bpp)
+{
+	static struct {
+		int bpp;
+		int src_w;
+		int dst_w;
+		int status;
+	} last;
+
+	int i;
+	int pos, inc;
+	unsigned char *eip;
+	unsigned char load, store;
+
+	/* See if we need to regenerate the copy buffer */
+	if ( (src_w == last.src_w) &&
+	     (dst_w == last.dst_w) && (bpp == last.bpp) ) {
+		return(last.status);
+	}
+	last.bpp = bpp;
+	last.src_w = src_w;
+	last.dst_w = dst_w;
+	last.status = -1;
+
+	switch (bpp) {
+	    case 1:
+		load = LOAD_BYTE;
+		store = STORE_BYTE;
+		break;
+	    case 2:
+	    case 4:
+		load = LOAD_WORD;
+		store = STORE_WORD;
+		break;
+	    default:
+		SDL_SetError("ASM stretch of %d bytes isn't supported\n", bpp);
+		return(-1);
+	}
+	pos = 0x10000;
+	inc = (src_w << 16) / dst_w;
+	eip = copy_row;
+	for ( i=0; i<dst_w; ++i ) {
+		while ( pos >= 0x10000L ) {
+			if ( bpp == 2 ) {
+				*eip++ = PREFIX16;
+			}
+			*eip++ = load;
+			pos -= 0x10000L;
+		}
+		if ( bpp == 2 ) {
+			*eip++ = PREFIX16;
+		}
+		*eip++ = store;
+		pos += inc;
+	}
+	*eip++ = RETURN;
+
+	/* Verify that we didn't overflow (too late!!!) */
+	if ( eip > (copy_row+sizeof(copy_row)) ) {
+		SDL_SetError("Copy buffer overflow");
+		return(-1);
+	}
+#ifdef HAVE_MPROTECT
+	/* Make the code executable */
+	if ( mprotect(copy_row, sizeof(copy_row), PROT_READ|PROT_WRITE|PROT_EXEC) < 0 ) {
+		SDL_SetError("Couldn't make copy buffer executable");
+		return(-1);
+	}
+#endif
+	last.status = 0;
+	return(0);
+}
+
+#endif /* USE_ASM_STRETCH */
+
+#define DEFINE_COPY_ROW(name, type)			\
+void name(type *src, int src_w, type *dst, int dst_w)	\
+{							\
+	int i;						\
+	int pos, inc;					\
+	type pixel = 0;					\
+							\
+	pos = 0x10000;					\
+	inc = (src_w << 16) / dst_w;			\
+	for ( i=dst_w; i>0; --i ) {			\
+		while ( pos >= 0x10000L ) {		\
+			pixel = *src++;			\
+			pos -= 0x10000L;		\
+		}					\
+		*dst++ = pixel;				\
+		pos += inc;				\
+	}						\
+}
+DEFINE_COPY_ROW(copy_row1, Uint8)
+DEFINE_COPY_ROW(copy_row2, Uint16)
+DEFINE_COPY_ROW(copy_row4, Uint32)
+
+/* The ASM code doesn't handle 24-bpp stretch blits */
+void copy_row3(Uint8 *src, int src_w, Uint8 *dst, int dst_w)
+{
+	int i;
+	int pos, inc;
+	Uint8 pixel[3] = { 0, 0, 0 };
+
+	pos = 0x10000;
+	inc = (src_w << 16) / dst_w;
+	for ( i=dst_w; i>0; --i ) {
+		while ( pos >= 0x10000L ) {
+			pixel[0] = *src++;
+			pixel[1] = *src++;
+			pixel[2] = *src++;
+			pos -= 0x10000L;
+		}
+		*dst++ = pixel[0];
+		*dst++ = pixel[1];
+		*dst++ = pixel[2];
+		pos += inc;
+	}
+}
+
+/* Perform a stretch blit between two surfaces of the same format.
+   NOTE:  This function is not safe to call from multiple threads!
+*/
+int SDL_SoftStretch(SDL_Surface *src, SDL_Rect *srcrect,
+                    SDL_Surface *dst, SDL_Rect *dstrect)
+{
+	int src_locked;
+	int dst_locked;
+	int pos, inc;
+	int dst_width;
+	int dst_maxrow;
+	int src_row, dst_row;
+	Uint8 *srcp = NULL;
+	Uint8 *dstp;
+	SDL_Rect full_src;
+	SDL_Rect full_dst;
+#ifdef USE_ASM_STRETCH
+	SDL_bool use_asm = SDL_TRUE;
+#ifdef __GNUC__
+	int u1, u2;
+#endif
+#endif /* USE_ASM_STRETCH */
+	const int bpp = dst->format->BytesPerPixel;
+
+	if ( src->format->BitsPerPixel != dst->format->BitsPerPixel ) {
+		SDL_SetError("Only works with same format surfaces");
+		return(-1);
+	}
+
+	/* Verify the blit rectangles */
+	if ( srcrect ) {
+		if ( (srcrect->x < 0) || (srcrect->y < 0) ||
+		     ((srcrect->x+srcrect->w) > src->w) ||
+		     ((srcrect->y+srcrect->h) > src->h) ) {
+			SDL_SetError("Invalid source blit rectangle");
+			return(-1);
+		}
+	} else {
+		full_src.x = 0;
+		full_src.y = 0;
+		full_src.w = src->w;
+		full_src.h = src->h;
+		srcrect = &full_src;
+	}
+	if ( dstrect ) {
+		if ( (dstrect->x < 0) || (dstrect->y < 0) ||
+		     ((dstrect->x+dstrect->w) > dst->w) ||
+		     ((dstrect->y+dstrect->h) > dst->h) ) {
+			SDL_SetError("Invalid destination blit rectangle");
+			return(-1);
+		}
+	} else {
+		full_dst.x = 0;
+		full_dst.y = 0;
+		full_dst.w = dst->w;
+		full_dst.h = dst->h;
+		dstrect = &full_dst;
+	}
+
+	/* Lock the destination if it's in hardware */
+	dst_locked = 0;
+	if ( SDL_MUSTLOCK(dst) ) {
+		if ( SDL_LockSurface(dst) < 0 ) {
+			SDL_SetError("Unable to lock destination surface");
+			return(-1);
+		}
+		dst_locked = 1;
+	}
+	/* Lock the source if it's in hardware */
+	src_locked = 0;
+	if ( SDL_MUSTLOCK(src) ) {
+		if ( SDL_LockSurface(src) < 0 ) {
+			if ( dst_locked ) {
+				SDL_UnlockSurface(dst);
+			}
+			SDL_SetError("Unable to lock source surface");
+			return(-1);
+		}
+		src_locked = 1;
+	}
+
+	/* Set up the data... */
+	pos = 0x10000;
+	inc = (srcrect->h << 16) / dstrect->h;
+	src_row = srcrect->y;
+	dst_row = dstrect->y;
+	dst_width = dstrect->w*bpp;
+
+#ifdef USE_ASM_STRETCH
+	/* Write the opcodes for this stretch */
+	if ( (bpp == 3) ||
+	     (generate_rowbytes(srcrect->w, dstrect->w, bpp) < 0) ) {
+		use_asm = SDL_FALSE;
+	}
+#endif
+
+	/* Perform the stretch blit */
+	for ( dst_maxrow = dst_row+dstrect->h; dst_row<dst_maxrow; ++dst_row ) {
+		dstp = (Uint8 *)dst->pixels + (dst_row*dst->pitch)
+		                            + (dstrect->x*bpp);
+		while ( pos >= 0x10000L ) {
+			srcp = (Uint8 *)src->pixels + (src_row*src->pitch)
+			                            + (srcrect->x*bpp);
+			++src_row;
+			pos -= 0x10000L;
+		}
+#ifdef USE_ASM_STRETCH
+		if (use_asm) {
+#ifdef __GNUC__
+			__asm__ __volatile__ (
+			"call *%4"
+			: "=&D" (u1), "=&S" (u2)
+			: "0" (dstp), "1" (srcp), "r" (copy_row)
+			: "memory" );
+#elif defined(_MSC_VER) || defined(__WATCOMC__)
+		{ void *code = copy_row;
+			__asm {
+				push edi
+				push esi
+	
+				mov edi, dstp
+				mov esi, srcp
+				call dword ptr code
+
+				pop esi
+				pop edi
+			}
+		}
+#else
+#error Need inline assembly for this compiler
+#endif
+		} else
+#endif
+		switch (bpp) {
+		    case 1:
+			copy_row1(srcp, srcrect->w, dstp, dstrect->w);
+			break;
+		    case 2:
+			copy_row2((Uint16 *)srcp, srcrect->w,
+			          (Uint16 *)dstp, dstrect->w);
+			break;
+		    case 3:
+			copy_row3(srcp, srcrect->w, dstp, dstrect->w);
+			break;
+		    case 4:
+			copy_row4((Uint32 *)srcp, srcrect->w,
+			          (Uint32 *)dstp, dstrect->w);
+			break;
+		}
+		pos += inc;
+	}
+
+	/* We need to unlock the surfaces if they're locked */
+	if ( dst_locked ) {
+		SDL_UnlockSurface(dst);
+	}
+	if ( src_locked ) {
+		SDL_UnlockSurface(src);
+	}
+	return(0);
+}
+