[sdl_omap.git] / src / video / SDL_stretch.c

/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2009 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
/* There's a bug with gcc 4.4.1 and -O2 where srcp doesn't get the correct
 * value after the first scanline.  FIXME? */
/*#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);
	}
#ifdef HAVE_MPROTECT
	/* Make the code writeable */
	if ( mprotect(copy_row, sizeof(copy_row), PROT_READ|PROT_WRITE) < 0 ) {
		SDL_SetError("Couldn't make copy buffer writeable");
		return(-1);
	}
#endif
	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 but not writeable */
	if ( mprotect(copy_row, sizeof(copy_row), PROT_READ|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);
}
Commit	Line	Data
e14743d1	1	/*
	2	SDL - Simple DirectMedia Layer
	3	Copyright (C) 1997-2009 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	/* This a stretch blit implementation based on ideas given to me by
	25	Tomasz Cejner - thanks! :)
	26
	27	April 27, 2000 - Sam Lantinga
	28	*/
	29
	30	#include "SDL_video.h"
	31	#include "SDL_blit.h"
	32
	33	/* This isn't ready for general consumption yet - it should be folded
	34	into the general blitting mechanism.
	35	*/
	36
	37	#if ((defined(_MFC_VER) && defined(_M_IX86)/* && !defined(_WIN32_WCE) still needed? */) \|\| \
	38	defined(__WATCOMC__) \|\| \
	39	(defined(__GNUC__) && defined(__i386__))) && SDL_ASSEMBLY_ROUTINES
	40	/* There's a bug with gcc 4.4.1 and -O2 where srcp doesn't get the correct
	41	* value after the first scanline. FIXME? */
	42	/#define USE_ASM_STRETCH/
	43	#endif
	44
	45	#ifdef USE_ASM_STRETCH
	46
	47	#ifdef HAVE_MPROTECT
	48	#include <sys/types.h>
	49	#include <sys/mman.h>
	50	#endif
	51	#ifdef __GNUC__
	52	#define PAGE_ALIGNED __attribute__((__aligned__(4096)))
	53	#else
	54	#define PAGE_ALIGNED
	55	#endif
	56
	57	#if defined(_M_IX86) \|\| defined(i386)
	58	#define PREFIX16 0x66
	59	#define STORE_BYTE 0xAA
	60	#define STORE_WORD 0xAB
	61	#define LOAD_BYTE 0xAC
	62	#define LOAD_WORD 0xAD
	63	#define RETURN 0xC3
	64	#else
65	#error Need assembly opcodes for this architecture
66	#endif
67
68	static unsigned char copy_row[4096] PAGE_ALIGNED;
69
70	static int generate_rowbytes(int src_w, int dst_w, int bpp)
71	{
72	static struct {
73	int bpp;
74	int src_w;
75	int dst_w;
76	int status;
77	} last;
78
79	int i;
80	int pos, inc;
81	unsigned char *eip;
82	unsigned char load, store;
83
84	/* See if we need to regenerate the copy buffer */
85	if ( (src_w == last.src_w) &&
86	(dst_w == last.dst_w) && (bpp == last.bpp) ) {
87	return(last.status);
88	}
89	last.bpp = bpp;
90	last.src_w = src_w;
91	last.dst_w = dst_w;
92	last.status = -1;
93
94	switch (bpp) {
95	case 1:
96	load = LOAD_BYTE;
97	store = STORE_BYTE;
98	break;
99	case 2:
100	case 4:
101	load = LOAD_WORD;
102	store = STORE_WORD;
103	break;
104	default:
105	SDL_SetError("ASM stretch of %d bytes isn't supported\n", bpp);
106	return(-1);
107	}
108	#ifdef HAVE_MPROTECT
109	/* Make the code writeable */
110	if ( mprotect(copy_row, sizeof(copy_row), PROT_READ\|PROT_WRITE) < 0 ) {
111	SDL_SetError("Couldn't make copy buffer writeable");
112	return(-1);
113	}
114	#endif
115	pos = 0x10000;
116	inc = (src_w << 16) / dst_w;
117	eip = copy_row;
118	for ( i=0; i<dst_w; ++i ) {
119	while ( pos >= 0x10000L ) {
120	if ( bpp == 2 ) {
121	*eip++ = PREFIX16;
122	}
123	*eip++ = load;
124	pos -= 0x10000L;
125	}
126	if ( bpp == 2 ) {
127	*eip++ = PREFIX16;
128	}
129	*eip++ = store;
130	pos += inc;
131	}
132	*eip++ = RETURN;
133
134	/* Verify that we didn't overflow (too late!!!) */
135	if ( eip > (copy_row+sizeof(copy_row)) ) {
136	SDL_SetError("Copy buffer overflow");
137	return(-1);
138	}
139	#ifdef HAVE_MPROTECT
140	/* Make the code executable but not writeable */
141	if ( mprotect(copy_row, sizeof(copy_row), PROT_READ\|PROT_EXEC) < 0 ) {
142	SDL_SetError("Couldn't make copy buffer executable");
143	return(-1);
144	}
145	#endif
146	last.status = 0;
147	return(0);
148	}
149
150	#endif /* USE_ASM_STRETCH */
151
152	#define DEFINE_COPY_ROW(name, type) \
153	void name(type src, int src_w, type dst, int dst_w) \
154	{ \
155	int i; \
156	int pos, inc; \
157	type pixel = 0; \
158	\
159	pos = 0x10000; \
160	inc = (src_w << 16) / dst_w; \
161	for ( i=dst_w; i>0; --i ) { \
162	while ( pos >= 0x10000L ) { \
163	pixel = *src++; \
164	pos -= 0x10000L; \
165	} \
166	*dst++ = pixel; \
167	pos += inc; \
168	} \
169	}
170	DEFINE_COPY_ROW(copy_row1, Uint8)
171	DEFINE_COPY_ROW(copy_row2, Uint16)
172	DEFINE_COPY_ROW(copy_row4, Uint32)
173
174	/* The ASM code doesn't handle 24-bpp stretch blits */
175	void copy_row3(Uint8 src, int src_w, Uint8 dst, int dst_w)
176	{
177	int i;
178	int pos, inc;
179	Uint8 pixel[3] = { 0, 0, 0 };
180
181	pos = 0x10000;
182	inc = (src_w << 16) / dst_w;
183	for ( i=dst_w; i>0; --i ) {
184	while ( pos >= 0x10000L ) {
185	pixel[0] = *src++;
186	pixel[1] = *src++;
187	pixel[2] = *src++;
188	pos -= 0x10000L;
189	}
190	*dst++ = pixel[0];
191	*dst++ = pixel[1];
192	*dst++ = pixel[2];
193	pos += inc;
194	}
195	}
196
197	/* Perform a stretch blit between two surfaces of the same format.
198	NOTE: This function is not safe to call from multiple threads!
199	*/
200	int SDL_SoftStretch(SDL_Surface src, SDL_Rect srcrect,
201	SDL_Surface dst, SDL_Rect dstrect)
202	{
203	int src_locked;
204	int dst_locked;
205	int pos, inc;
206	int dst_width;
207	int dst_maxrow;
208	int src_row, dst_row;
209	Uint8 *srcp = NULL;
210	Uint8 *dstp;
211	SDL_Rect full_src;
212	SDL_Rect full_dst;
213	#ifdef USE_ASM_STRETCH
214	SDL_bool use_asm = SDL_TRUE;
215	#ifdef __GNUC__
216	int u1, u2;
217	#endif
218	#endif /* USE_ASM_STRETCH */
219	const int bpp = dst->format->BytesPerPixel;
220
221	if ( src->format->BitsPerPixel != dst->format->BitsPerPixel ) {
222	SDL_SetError("Only works with same format surfaces");
223	return(-1);
224	}
225
226	/* Verify the blit rectangles */
227	if ( srcrect ) {
228	if ( (srcrect->x < 0) \|\| (srcrect->y < 0) \|\|
229	((srcrect->x+srcrect->w) > src->w) \|\|
230	((srcrect->y+srcrect->h) > src->h) ) {
231	SDL_SetError("Invalid source blit rectangle");
232	return(-1);
233	}
234	} else {
235	full_src.x = 0;
236	full_src.y = 0;
237	full_src.w = src->w;
238	full_src.h = src->h;
239	srcrect = &full_src;
240	}
241	if ( dstrect ) {
242	if ( (dstrect->x < 0) \|\| (dstrect->y < 0) \|\|
243	((dstrect->x+dstrect->w) > dst->w) \|\|
244	((dstrect->y+dstrect->h) > dst->h) ) {
245	SDL_SetError("Invalid destination blit rectangle");
246	return(-1);
247	}
248	} else {
249	full_dst.x = 0;
250	full_dst.y = 0;
251	full_dst.w = dst->w;
252	full_dst.h = dst->h;
253	dstrect = &full_dst;
254	}
255
256	/* Lock the destination if it's in hardware */
257	dst_locked = 0;
258	if ( SDL_MUSTLOCK(dst) ) {
259	if ( SDL_LockSurface(dst) < 0 ) {
260	SDL_SetError("Unable to lock destination surface");
261	return(-1);
262	}
263	dst_locked = 1;
264	}
265	/* Lock the source if it's in hardware */
266	src_locked = 0;
267	if ( SDL_MUSTLOCK(src) ) {
268	if ( SDL_LockSurface(src) < 0 ) {
269	if ( dst_locked ) {
270	SDL_UnlockSurface(dst);
271	}
272	SDL_SetError("Unable to lock source surface");
273	return(-1);
274	}
275	src_locked = 1;
276	}
277
278	/* Set up the data... */
279	pos = 0x10000;
280	inc = (srcrect->h << 16) / dstrect->h;
281	src_row = srcrect->y;
282	dst_row = dstrect->y;
283	dst_width = dstrect->w*bpp;
284
285	#ifdef USE_ASM_STRETCH
286	/* Write the opcodes for this stretch */
287	if ( (bpp == 3) \|\|
288	(generate_rowbytes(srcrect->w, dstrect->w, bpp) < 0) ) {
289	use_asm = SDL_FALSE;
290	}
291	#endif
292
293	/* Perform the stretch blit */
294	for ( dst_maxrow = dst_row+dstrect->h; dst_row<dst_maxrow; ++dst_row ) {
295	dstp = (Uint8 )dst->pixels + (dst_rowdst->pitch)
296	+ (dstrect->x*bpp);
297	while ( pos >= 0x10000L ) {
298	srcp = (Uint8 )src->pixels + (src_rowsrc->pitch)
299	+ (srcrect->x*bpp);
300	++src_row;
301	pos -= 0x10000L;
302	}
303	#ifdef USE_ASM_STRETCH
304	if (use_asm) {
305	#ifdef __GNUC__
306	__asm__ __volatile__ (
307	"call *%4"
308	: "=&D" (u1), "=&S" (u2)
309	: "0" (dstp), "1" (srcp), "r" (copy_row)
310	: "memory" );
311	#elif defined(_MSC_VER) \|\| defined(__WATCOMC__)
312	{ void *code = copy_row;
313	__asm {
314	push edi
315	push esi
316
317	mov edi, dstp
318	mov esi, srcp
319	call dword ptr code
320
321	pop esi
322	pop edi
323	}
324	}
325	#else
326	#error Need inline assembly for this compiler
327	#endif
328	} else
329	#endif
330	switch (bpp) {
331	case 1:
332	copy_row1(srcp, srcrect->w, dstp, dstrect->w);
333	break;
334	case 2:
335	copy_row2((Uint16 *)srcp, srcrect->w,
336	(Uint16 *)dstp, dstrect->w);
337	break;
338	case 3:
339	copy_row3(srcp, srcrect->w, dstp, dstrect->w);
340	break;
341	case 4:
342	copy_row4((Uint32 *)srcp, srcrect->w,
343	(Uint32 *)dstp, dstrect->w);
344	break;
345	}
346	pos += inc;
347	}
348
349	/* We need to unlock the surfaces if they're locked */
350	if ( dst_locked ) {
351	SDL_UnlockSurface(dst);
352	}
353	if ( src_locked ) {
354	SDL_UnlockSurface(src);
355	}
356	return(0);
357	}
358