annotate src/video/SDL_blit_slow.c @ 3442:204609180482

Compare against the correct image
author Sam Lantinga <slouken@libsdl.org>
date Wed, 18 Nov 2009 06:15:21 +0000
parents 99210400e8b9
children c5fe76962106
rev   line source
2256
e893d24ad8db Getting ready to add slow blitters. Everyone will love me. :)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
1 /*
e893d24ad8db Getting ready to add slow blitters. Everyone will love me. :)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
2 SDL - Simple DirectMedia Layer
2859
99210400e8b9 Updated copyright date
Sam Lantinga <slouken@libsdl.org>
parents: 2824
diff changeset
3 Copyright (C) 1997-2009 Sam Lantinga
2256
e893d24ad8db Getting ready to add slow blitters. Everyone will love me. :)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
4
e893d24ad8db Getting ready to add slow blitters. Everyone will love me. :)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
5 This library is free software; you can redistribute it and/or
e893d24ad8db Getting ready to add slow blitters. Everyone will love me. :)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
6 modify it under the terms of the GNU Lesser General Public
e893d24ad8db Getting ready to add slow blitters. Everyone will love me. :)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
7 License as published by the Free Software Foundation; either
e893d24ad8db Getting ready to add slow blitters. Everyone will love me. :)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
8 version 2.1 of the License, or (at your option) any later version.
e893d24ad8db Getting ready to add slow blitters. Everyone will love me. :)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
9
e893d24ad8db Getting ready to add slow blitters. Everyone will love me. :)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
10 This library is distributed in the hope that it will be useful,
e893d24ad8db Getting ready to add slow blitters. Everyone will love me. :)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
e893d24ad8db Getting ready to add slow blitters. Everyone will love me. :)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
e893d24ad8db Getting ready to add slow blitters. Everyone will love me. :)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
13 Lesser General Public License for more details.
e893d24ad8db Getting ready to add slow blitters. Everyone will love me. :)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
14
e893d24ad8db Getting ready to add slow blitters. Everyone will love me. :)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
15 You should have received a copy of the GNU Lesser General Public
e893d24ad8db Getting ready to add slow blitters. Everyone will love me. :)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
16 License along with this library; if not, write to the Free Software
e893d24ad8db Getting ready to add slow blitters. Everyone will love me. :)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
17 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
e893d24ad8db Getting ready to add slow blitters. Everyone will love me. :)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
18
e893d24ad8db Getting ready to add slow blitters. Everyone will love me. :)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
19 Sam Lantinga
e893d24ad8db Getting ready to add slow blitters. Everyone will love me. :)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
20 slouken@libsdl.org
e893d24ad8db Getting ready to add slow blitters. Everyone will love me. :)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
21 */
e893d24ad8db Getting ready to add slow blitters. Everyone will love me. :)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
22 #include "SDL_config.h"
e893d24ad8db Getting ready to add slow blitters. Everyone will love me. :)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
23
e893d24ad8db Getting ready to add slow blitters. Everyone will love me. :)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
24 #include "SDL_video.h"
e893d24ad8db Getting ready to add slow blitters. Everyone will love me. :)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
25 #include "SDL_blit.h"
e893d24ad8db Getting ready to add slow blitters. Everyone will love me. :)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
26
e893d24ad8db Getting ready to add slow blitters. Everyone will love me. :)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
27 /* The ONE TRUE BLITTER
e893d24ad8db Getting ready to add slow blitters. Everyone will love me. :)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
28 * This puppy has to handle all the unoptimized cases - yes, it's slow.
e893d24ad8db Getting ready to add slow blitters. Everyone will love me. :)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
29 */
2824
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
30 void
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
31 SDL_Blit_Slow(SDL_BlitInfo * info)
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
32 {
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
33 const int flags = info->flags;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
34 const Uint32 modulateR = info->r;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
35 const Uint32 modulateG = info->g;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
36 const Uint32 modulateB = info->b;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
37 const Uint32 modulateA = info->a;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
38 Uint32 srcpixel;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
39 Uint32 srcR, srcG, srcB, srcA;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
40 Uint32 dstpixel;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
41 Uint32 dstR, dstG, dstB, dstA;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
42 int srcy, srcx;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
43 int posy, posx;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
44 int incy, incx;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
45 SDL_PixelFormat *src_fmt = info->src_fmt;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
46 SDL_PixelFormat *dst_fmt = info->dst_fmt;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
47 int srcbpp = src_fmt->BytesPerPixel;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
48 int dstbpp = dst_fmt->BytesPerPixel;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
49
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
50 srcy = 0;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
51 posy = 0;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
52 incy = (info->src_h << 16) / info->dst_h;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
53 incx = (info->src_w << 16) / info->dst_w;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
54
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
55 while (info->dst_h--) {
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
56 Uint8 *src;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
57 Uint8 *dst = (Uint8 *) info->dst;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
58 int n = info->dst_w;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
59 srcx = -1;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
60 posx = 0x10000L;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
61 while (posy >= 0x10000L) {
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
62 ++srcy;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
63 posy -= 0x10000L;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
64 }
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
65 while (n--) {
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
66 if (posx >= 0x10000L) {
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
67 while (posx >= 0x10000L) {
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
68 ++srcx;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
69 posx -= 0x10000L;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
70 }
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
71 src =
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
72 (info->src + (srcy * info->src_pitch) + (srcx * srcbpp));
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
73 }
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
74 if (src_fmt->Amask) {
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
75 DISEMBLE_RGBA(src, srcbpp, src_fmt, srcpixel, srcR, srcG,
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
76 srcB, srcA);
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
77 } else {
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
78 DISEMBLE_RGB(src, srcbpp, src_fmt, srcpixel, srcR, srcG,
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
79 srcB);
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
80 srcA = 0xFF;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
81 }
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
82 if (flags & SDL_COPY_COLORKEY) {
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
83 /* srcpixel isn't set for 24 bpp */
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
84 if (srcbpp == 24) {
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
85 srcpixel = (srcR << src_fmt->Rshift) |
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
86 (srcG << src_fmt->Gshift) | (srcB << src_fmt->Bshift);
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
87 }
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
88 if (srcpixel == info->colorkey) {
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
89 posx += incx;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
90 dst += dstbpp;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
91 continue;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
92 }
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
93 }
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
94 if (dst_fmt->Amask) {
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
95 DISEMBLE_RGBA(dst, dstbpp, dst_fmt, dstpixel, dstR, dstG,
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
96 dstB, dstA);
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
97 } else {
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
98 DISEMBLE_RGB(dst, dstbpp, dst_fmt, dstpixel, dstR, dstG,
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
99 dstB);
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
100 dstA = 0xFF;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
101 }
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
102
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
103 if (flags & SDL_COPY_MODULATE_COLOR) {
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
104 srcR = (srcR * modulateR) / 255;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
105 srcG = (srcG * modulateG) / 255;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
106 srcB = (srcB * modulateB) / 255;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
107 }
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
108 if (flags & SDL_COPY_MODULATE_ALPHA) {
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
109 srcA = (srcA * modulateA) / 255;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
110 }
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
111 if (flags & (SDL_COPY_BLEND | SDL_COPY_ADD)) {
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
112 /* This goes away if we ever use premultiplied alpha */
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
113 if (srcA < 255) {
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
114 srcR = (srcR * srcA) / 255;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
115 srcG = (srcG * srcA) / 255;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
116 srcB = (srcB * srcA) / 255;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
117 }
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
118 }
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
119 switch (flags &
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
120 (SDL_COPY_MASK | SDL_COPY_BLEND | SDL_COPY_ADD |
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
121 SDL_COPY_MOD)) {
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
122 case 0:
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
123 dstR = srcR;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
124 dstG = srcG;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
125 dstB = srcB;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
126 dstA = srcA;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
127 break;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
128 case SDL_COPY_MASK:
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
129 if (srcA) {
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
130 dstR = srcR;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
131 dstG = srcG;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
132 dstB = srcB;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
133 }
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
134 break;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
135 case SDL_COPY_BLEND:
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
136 dstR = srcR + ((255 - srcA) * dstR) / 255;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
137 dstG = srcG + ((255 - srcA) * dstG) / 255;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
138 dstB = srcB + ((255 - srcA) * dstB) / 255;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
139 break;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
140 case SDL_COPY_ADD:
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
141 dstR = srcR + dstR;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
142 if (dstR > 255)
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
143 dstR = 255;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
144 dstG = srcG + dstG;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
145 if (dstG > 255)
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
146 dstG = 255;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
147 dstB = srcB + dstB;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
148 if (dstB > 255)
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
149 dstB = 255;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
150 break;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
151 case SDL_COPY_MOD:
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
152 dstR = (srcR * dstR) / 255;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
153 dstG = (srcG * dstG) / 255;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
154 dstB = (srcB * dstB) / 255;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
155 break;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
156 }
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
157 if (dst_fmt->Amask) {
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
158 ASSEMBLE_RGBA(dst, dstbpp, dst_fmt, dstR, dstG, dstB, dstA);
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
159 } else {
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
160 ASSEMBLE_RGB(dst, dstbpp, dst_fmt, dstR, dstG, dstB);
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
161 }
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
162 posx += incx;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
163 dst += dstbpp;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
164 }
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
165 posy += incy;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
166 info->dst += info->dst_pitch;
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
167 }
4dba7aa7ea77 Added slow but complete blit fallback
Sam Lantinga <slouken@libsdl.org>
parents: 2256
diff changeset
168 }
2256
e893d24ad8db Getting ready to add slow blitters. Everyone will love me. :)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
169
e893d24ad8db Getting ready to add slow blitters. Everyone will love me. :)
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
170 /* vi: set ts=4 sw=4 expandtab: */