annotate src/video/SDL_stretch.c @ 252:e8157fcb3114

Updated the source with the correct e-mail address
author Sam Lantinga <slouken@libsdl.org>
date Fri, 14 Dec 2001 12:38:15 +0000
parents 74212992fb08
children 051b991765ba
rev   line source
0
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
1 /*
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
2 SDL - Simple DirectMedia Layer
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
3 Copyright (C) 1997, 1998, 1999, 2000, 2001 Sam Lantinga
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
4
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
5 This library is free software; you can redistribute it and/or
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
6 modify it under the terms of the GNU Library General Public
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
7 License as published by the Free Software Foundation; either
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
8 version 2 of the License, or (at your option) any later version.
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
9
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
10 This library is distributed in the hope that it will be useful,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
13 Library General Public License for more details.
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
14
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
15 You should have received a copy of the GNU Library General Public
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
16 License along with this library; if not, write to the Free
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
18
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
19 Sam Lantinga
252
e8157fcb3114 Updated the source with the correct e-mail address
Sam Lantinga <slouken@libsdl.org>
parents: 0
diff changeset
20 slouken@libsdl.org
0
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
21 */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
22
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
23 #ifdef SAVE_RCSID
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
24 static char rcsid =
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
25 "@(#) $Id$";
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
26 #endif
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
27
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
28 /* This a stretch blit implementation based on ideas given to me by
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
29 Tomasz Cejner - thanks! :)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
30
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
31 April 27, 2000 - Sam Lantinga
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
32 */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
33
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
34 #include "SDL_error.h"
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
35 #include "SDL_video.h"
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
36 #include "SDL_blit.h"
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
37
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
38 /* This isn't ready for general consumption yet - it should be folded
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
39 into the general blitting mechanism.
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
40 */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
41
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
42 #if (defined(WIN32) && !defined(_M_ALPHA) && !defined(_WIN32_WCE)) || \
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
43 defined(i386) && defined(__GNUC__) && defined(USE_ASMBLIT)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
44 #define USE_ASM_STRETCH
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
45 #endif
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
46
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
47 #ifdef USE_ASM_STRETCH
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
48
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
49 #if defined(WIN32) || defined(i386)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
50 #define PREFIX16 0x66
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
51 #define STORE_BYTE 0xAA
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
52 #define STORE_WORD 0xAB
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
53 #define LOAD_BYTE 0xAC
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
54 #define LOAD_WORD 0xAD
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
55 #define RETURN 0xC3
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
56 #else
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
57 #error Need assembly opcodes for this architecture
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
58 #endif
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
59
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
60 #if defined(__ELF__) && defined(__GNUC__)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
61 extern unsigned char _copy_row[4096] __attribute__ ((alias ("copy_row")));
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
62 #endif
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
63 static unsigned char copy_row[4096];
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
64
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
65 static int generate_rowbytes(int src_w, int dst_w, int bpp)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
66 {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
67 static struct {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
68 int bpp;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
69 int src_w;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
70 int dst_w;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
71 } last;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
72
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
73 int i;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
74 int pos, inc;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
75 unsigned char *eip;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
76 unsigned char load, store;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
77
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
78 /* See if we need to regenerate the copy buffer */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
79 if ( (src_w == last.src_w) &&
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
80 (dst_w == last.src_w) && (bpp == last.bpp) ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
81 return(0);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
82 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
83 last.bpp = bpp;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
84 last.src_w = src_w;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
85 last.dst_w = dst_w;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
86
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
87 switch (bpp) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
88 case 1:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
89 load = LOAD_BYTE;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
90 store = STORE_BYTE;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
91 break;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
92 case 2:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
93 case 4:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
94 load = LOAD_WORD;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
95 store = STORE_WORD;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
96 break;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
97 default:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
98 SDL_SetError("ASM stretch of %d bytes isn't supported\n", bpp);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
99 return(-1);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
100 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
101 pos = 0x10000;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
102 inc = (src_w << 16) / dst_w;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
103 eip = copy_row;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
104 for ( i=0; i<dst_w; ++i ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
105 while ( pos >= 0x10000L ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
106 if ( bpp == 2 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
107 *eip++ = PREFIX16;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
108 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
109 *eip++ = load;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
110 pos -= 0x10000L;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
111 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
112 if ( bpp == 2 ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
113 *eip++ = PREFIX16;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
114 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
115 *eip++ = store;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
116 pos += inc;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
117 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
118 *eip++ = RETURN;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
119
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
120 /* Verify that we didn't overflow (too late) */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
121 if ( eip > (copy_row+sizeof(copy_row)) ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
122 SDL_SetError("Copy buffer overflow");
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
123 return(-1);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
124 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
125 return(0);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
126 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
127
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
128 #else
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
129
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
130 #define DEFINE_COPY_ROW(name, type) \
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
131 void name(type *src, int src_w, type *dst, int dst_w) \
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
132 { \
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
133 int i; \
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
134 int pos, inc; \
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
135 type pixel = 0; \
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
136 \
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
137 pos = 0x10000; \
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
138 inc = (src_w << 16) / dst_w; \
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
139 for ( i=dst_w; i>0; --i ) { \
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
140 while ( pos >= 0x10000L ) { \
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
141 pixel = *src++; \
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
142 pos -= 0x10000L; \
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
143 } \
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
144 *dst++ = pixel; \
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
145 pos += inc; \
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
146 } \
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
147 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
148 DEFINE_COPY_ROW(copy_row1, Uint8)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
149 DEFINE_COPY_ROW(copy_row2, Uint16)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
150 DEFINE_COPY_ROW(copy_row4, Uint32)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
151
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
152 #endif /* USE_ASM_STRETCH */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
153
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
154 /* The ASM code doesn't handle 24-bpp stretch blits */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
155 void copy_row3(Uint8 *src, int src_w, Uint8 *dst, int dst_w)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
156 {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
157 int i;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
158 int pos, inc;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
159 Uint8 pixel[3];
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
160
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
161 pos = 0x10000;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
162 inc = (src_w << 16) / dst_w;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
163 for ( i=dst_w; i>0; --i ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
164 while ( pos >= 0x10000L ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
165 pixel[0] = *src++;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
166 pixel[1] = *src++;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
167 pixel[2] = *src++;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
168 pos -= 0x10000L;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
169 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
170 *dst++ = pixel[0];
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
171 *dst++ = pixel[1];
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
172 *dst++ = pixel[2];
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
173 pos += inc;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
174 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
175 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
176
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
177 /* Perform a stretch blit between two surfaces of the same format.
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
178 NOTE: This function is not safe to call from multiple threads!
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
179 */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
180 int SDL_SoftStretch(SDL_Surface *src, SDL_Rect *srcrect,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
181 SDL_Surface *dst, SDL_Rect *dstrect)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
182 {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
183 int pos, inc;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
184 int dst_width;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
185 int dst_maxrow;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
186 int src_row, dst_row;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
187 Uint8 *srcp = NULL;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
188 Uint8 *dstp;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
189 SDL_Rect full_src;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
190 SDL_Rect full_dst;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
191 #if defined(USE_ASM_STRETCH) && defined(__GNUC__)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
192 int u1, u2;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
193 #endif
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
194 const int bpp = dst->format->BytesPerPixel;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
195
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
196 if ( src->format->BitsPerPixel != dst->format->BitsPerPixel ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
197 SDL_SetError("Only works with same format surfaces");
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
198 return(-1);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
199 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
200
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
201 /* Verify the blit rectangles */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
202 if ( srcrect ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
203 if ( (srcrect->x < 0) || (srcrect->y < 0) ||
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
204 ((srcrect->x+srcrect->w) > src->w) ||
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
205 ((srcrect->y+srcrect->h) > src->h) ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
206 SDL_SetError("Invalid source blit rectangle");
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
207 return(-1);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
208 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
209 } else {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
210 full_src.x = 0;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
211 full_src.y = 0;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
212 full_src.w = src->w;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
213 full_src.h = src->h;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
214 srcrect = &full_src;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
215 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
216 if ( dstrect ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
217 if ( (dstrect->x < 0) || (dstrect->y < 0) ||
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
218 ((dstrect->x+dstrect->w) > dst->w) ||
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
219 ((dstrect->y+dstrect->h) > dst->h) ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
220 SDL_SetError("Invalid destination blit rectangle");
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
221 return(-1);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
222 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
223 } else {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
224 full_dst.x = 0;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
225 full_dst.y = 0;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
226 full_dst.w = dst->w;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
227 full_dst.h = dst->h;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
228 dstrect = &full_dst;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
229 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
230
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
231 /* Set up the data... */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
232 pos = 0x10000;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
233 inc = (srcrect->h << 16) / dstrect->h;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
234 src_row = srcrect->y;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
235 dst_row = dstrect->y;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
236 dst_width = dstrect->w*bpp;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
237
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
238 #ifdef USE_ASM_STRETCH
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
239 /* Write the opcodes for this stretch */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
240 if ( (bpp != 3) &&
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
241 (generate_rowbytes(srcrect->w, dstrect->w, bpp) < 0) ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
242 return(-1);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
243 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
244 #endif
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
245
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
246 /* Perform the stretch blit */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
247 for ( dst_maxrow = dst_row+dstrect->h; dst_row<dst_maxrow; ++dst_row ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
248 dstp = (Uint8 *)dst->pixels + (dst_row*dst->pitch)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
249 + (dstrect->x*bpp);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
250 while ( pos >= 0x10000L ) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
251 srcp = (Uint8 *)src->pixels + (src_row*src->pitch)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
252 + (srcrect->x*bpp);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
253 ++src_row;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
254 pos -= 0x10000L;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
255 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
256 #ifdef USE_ASM_STRETCH
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
257 switch (bpp) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
258 case 3:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
259 copy_row3(srcp, srcrect->w, dstp, dstrect->w);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
260 break;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
261 default:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
262 #ifdef __GNUC__
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
263 __asm__ __volatile__ ("
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
264 call _copy_row
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
265 "
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
266 : "=&D" (u1), "=&S" (u2)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
267 : "0" (dstp), "1" (srcp)
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
268 : "memory" );
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
269 #else
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
270 #ifdef WIN32
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
271 { void *code = &copy_row;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
272 __asm {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
273 push edi
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
274 push esi
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
275
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
276 mov edi, dstp
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
277 mov esi, srcp
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
278 call dword ptr code
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
279
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
280 pop esi
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
281 pop edi
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
282 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
283 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
284 #else
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
285 #error Need inline assembly for this compiler
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
286 #endif
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
287 #endif /* __GNUC__ */
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
288 break;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
289 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
290 #else
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
291 switch (bpp) {
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
292 case 1:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
293 copy_row1(srcp, srcrect->w, dstp, dstrect->w);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
294 break;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
295 case 2:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
296 copy_row2((Uint16 *)srcp, srcrect->w,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
297 (Uint16 *)dstp, dstrect->w);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
298 break;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
299 case 3:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
300 copy_row3(srcp, srcrect->w, dstp, dstrect->w);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
301 break;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
302 case 4:
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
303 copy_row4((Uint32 *)srcp, srcrect->w,
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
304 (Uint32 *)dstp, dstrect->w);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
305 break;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
306 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
307 #endif
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
308 pos += inc;
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
309 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
310 return(0);
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
311 }
74212992fb08 Initial revision
Sam Lantinga <slouken@lokigames.com>
parents:
diff changeset
312