File: | ui/sdl_zoom_template.h |
Location: | line 77, column 5 |
Description: | Value stored to 'sp' is never read |
1 | /* |
2 | * SDL_zoom_template - surface scaling |
3 | * |
4 | * Copyright (c) 2009 Citrix Systems, Inc. |
5 | * |
6 | * Derived from: SDL_rotozoom, LGPL (c) A. Schiffler from the SDL_gfx library. |
7 | * Modifications by Stefano Stabellini. |
8 | * |
9 | * This work is licensed under the terms of the GNU GPL version 2. |
10 | * See the COPYING file in the top-level directory. |
11 | * |
12 | */ |
13 | |
14 | #if BPP == 16 |
15 | #define SDL_TYPE Uint16 |
16 | #elif BPP == 32 |
17 | #define SDL_TYPE Uint32 |
18 | #else |
19 | #error unsupport depth |
20 | #endif |
21 | |
22 | /* |
23 | * Simple helper functions to make the code looks nicer |
24 | * |
25 | * Assume spf = source SDL_PixelFormat |
26 | * dpf = dest SDL_PixelFormat |
27 | * |
28 | */ |
29 | #define getRed(color)(((color) & spf->Rmask) >> spf->Rshift) (((color) & spf->Rmask) >> spf->Rshift) |
30 | #define getGreen(color)(((color) & spf->Gmask) >> spf->Gshift) (((color) & spf->Gmask) >> spf->Gshift) |
31 | #define getBlue(color)(((color) & spf->Bmask) >> spf->Bshift) (((color) & spf->Bmask) >> spf->Bshift) |
32 | #define getAlpha(color)(((color) & spf->Amask) >> spf->Ashift) (((color) & spf->Amask) >> spf->Ashift) |
33 | |
34 | #define setRed(r, pcolor)do { *pcolor = ((*pcolor) & (~(dpf->Rmask))) + (((r) & (dpf->Rmask >> dpf->Rshift)) << dpf->Rshift ); } while (0); do { \ |
35 | *pcolor = ((*pcolor) & (~(dpf->Rmask))) + \ |
36 | (((r) & (dpf->Rmask >> dpf->Rshift)) << dpf->Rshift); \ |
37 | } while (0); |
38 | |
39 | #define setGreen(g, pcolor)do { *pcolor = ((*pcolor) & (~(dpf->Gmask))) + (((g) & (dpf->Gmask >> dpf->Gshift)) << dpf->Gshift ); } while (0); do { \ |
40 | *pcolor = ((*pcolor) & (~(dpf->Gmask))) + \ |
41 | (((g) & (dpf->Gmask >> dpf->Gshift)) << dpf->Gshift); \ |
42 | } while (0); |
43 | |
44 | #define setBlue(b, pcolor)do { *pcolor = ((*pcolor) & (~(dpf->Bmask))) + (((b) & (dpf->Bmask >> dpf->Bshift)) << dpf->Bshift ); } while (0); do { \ |
45 | *pcolor = ((*pcolor) & (~(dpf->Bmask))) + \ |
46 | (((b) & (dpf->Bmask >> dpf->Bshift)) << dpf->Bshift); \ |
47 | } while (0); |
48 | |
49 | #define setAlpha(a, pcolor)do { *pcolor = ((*pcolor) & (~(dpf->Amask))) + (((a) & (dpf->Amask >> dpf->Ashift)) << dpf->Ashift ); } while (0); do { \ |
50 | *pcolor = ((*pcolor) & (~(dpf->Amask))) + \ |
51 | (((a) & (dpf->Amask >> dpf->Ashift)) << dpf->Ashift); \ |
52 | } while (0); |
53 | |
54 | static void glue(sdl_zoom_rgb, BPP)sdl_zoom_rgbBPP(SDL_Surface *src, SDL_Surface *dst, int smooth, |
55 | SDL_Rect *dst_rect) |
56 | { |
57 | int x, y, sx, sy, *sax, *say, *csax, *csay, csx, csy, ex, ey, t1, t2, sstep, sstep_jump; |
58 | SDL_TYPE *c00, *c01, *c10, *c11, *sp, *csp, *dp; |
59 | int d_gap; |
60 | SDL_PixelFormat *spf = src->format; |
61 | SDL_PixelFormat *dpf = dst->format; |
62 | |
63 | if (smooth) { |
64 | /* For interpolation: assume source dimension is one pixel. |
65 | * Smaller here to avoid overflow on right and bottom edge. |
66 | */ |
67 | sx = (int) (65536.0 * (float) (src->w - 1) / (float) dst->w); |
68 | sy = (int) (65536.0 * (float) (src->h - 1) / (float) dst->h); |
69 | } else { |
70 | sx = (int) (65536.0 * (float) src->w / (float) dst->w); |
71 | sy = (int) (65536.0 * (float) src->h / (float) dst->h); |
72 | } |
73 | |
74 | sax = g_new(int, dst->w + 1)((int *) g_malloc_n ((dst->w + 1), sizeof (int))); |
75 | say = g_new(int, dst->h + 1)((int *) g_malloc_n ((dst->h + 1), sizeof (int))); |
76 | |
77 | sp = csp = (SDL_TYPE *) src->pixels; |
Value stored to 'sp' is never read | |
78 | dp = (SDL_TYPE *) (dst->pixels + dst_rect->y * dst->pitch + |
79 | dst_rect->x * dst->format->BytesPerPixel); |
80 | |
81 | csx = 0; |
82 | csax = sax; |
83 | for (x = 0; x <= dst->w; x++) { |
84 | *csax = csx; |
85 | csax++; |
86 | csx &= 0xffff; |
87 | csx += sx; |
88 | } |
89 | csy = 0; |
90 | csay = say; |
91 | for (y = 0; y <= dst->h; y++) { |
92 | *csay = csy; |
93 | csay++; |
94 | csy &= 0xffff; |
95 | csy += sy; |
96 | } |
97 | |
98 | d_gap = dst->pitch - dst_rect->w * dst->format->BytesPerPixel; |
99 | |
100 | if (smooth) { |
101 | csay = say; |
102 | for (y = 0; y < dst_rect->y; y++) { |
103 | csay++; |
104 | sstep = (*csay >> 16) * src->pitch; |
105 | csp = (SDL_TYPE *) ((Uint8 *) csp + sstep); |
106 | } |
107 | |
108 | /* Calculate sstep_jump */ |
109 | csax = sax; |
110 | sstep_jump = 0; |
111 | for (x = 0; x < dst_rect->x; x++) { |
112 | csax++; |
113 | sstep = (*csax >> 16); |
114 | sstep_jump += sstep; |
115 | } |
116 | |
117 | for (y = 0; y < dst_rect->h ; y++) { |
118 | /* Setup colour source pointers */ |
119 | c00 = csp + sstep_jump; |
120 | c01 = c00 + 1; |
121 | c10 = (SDL_TYPE *) ((Uint8 *) csp + src->pitch) + sstep_jump; |
122 | c11 = c10 + 1; |
123 | csax = sax + dst_rect->x; |
124 | |
125 | for (x = 0; x < dst_rect->w; x++) { |
126 | |
127 | /* Interpolate colours */ |
128 | ex = (*csax & 0xffff); |
129 | ey = (*csay & 0xffff); |
130 | t1 = ((((getRed(*c01)(((*c01) & spf->Rmask) >> spf->Rshift) - getRed(*c00)(((*c00) & spf->Rmask) >> spf->Rshift)) * ex) >> 16) + |
131 | getRed(*c00)(((*c00) & spf->Rmask) >> spf->Rshift)) & (dpf->Rmask >> dpf->Rshift); |
132 | t2 = ((((getRed(*c11)(((*c11) & spf->Rmask) >> spf->Rshift) - getRed(*c10)(((*c10) & spf->Rmask) >> spf->Rshift)) * ex) >> 16) + |
133 | getRed(*c10)(((*c10) & spf->Rmask) >> spf->Rshift)) & (dpf->Rmask >> dpf->Rshift); |
134 | setRed((((t2 - t1) * ey) >> 16) + t1, dp)do { *dp = ((*dp) & (~(dpf->Rmask))) + ((((((t2 - t1) * ey) >> 16) + t1) & (dpf->Rmask >> dpf-> Rshift)) << dpf->Rshift); } while (0);; |
135 | t1 = ((((getGreen(*c01)(((*c01) & spf->Gmask) >> spf->Gshift) - getGreen(*c00)(((*c00) & spf->Gmask) >> spf->Gshift)) * ex) >> 16) + |
136 | getGreen(*c00)(((*c00) & spf->Gmask) >> spf->Gshift)) & (dpf->Gmask >> dpf->Gshift); |
137 | t2 = ((((getGreen(*c11)(((*c11) & spf->Gmask) >> spf->Gshift) - getGreen(*c10)(((*c10) & spf->Gmask) >> spf->Gshift)) * ex) >> 16) + |
138 | getGreen(*c10)(((*c10) & spf->Gmask) >> spf->Gshift)) & (dpf->Gmask >> dpf->Gshift); |
139 | setGreen((((t2 - t1) * ey) >> 16) + t1, dp)do { *dp = ((*dp) & (~(dpf->Gmask))) + ((((((t2 - t1) * ey) >> 16) + t1) & (dpf->Gmask >> dpf-> Gshift)) << dpf->Gshift); } while (0);; |
140 | t1 = ((((getBlue(*c01)(((*c01) & spf->Bmask) >> spf->Bshift) - getBlue(*c00)(((*c00) & spf->Bmask) >> spf->Bshift)) * ex) >> 16) + |
141 | getBlue(*c00)(((*c00) & spf->Bmask) >> spf->Bshift)) & (dpf->Bmask >> dpf->Bshift); |
142 | t2 = ((((getBlue(*c11)(((*c11) & spf->Bmask) >> spf->Bshift) - getBlue(*c10)(((*c10) & spf->Bmask) >> spf->Bshift)) * ex) >> 16) + |
143 | getBlue(*c10)(((*c10) & spf->Bmask) >> spf->Bshift)) & (dpf->Bmask >> dpf->Bshift); |
144 | setBlue((((t2 - t1) * ey) >> 16) + t1, dp)do { *dp = ((*dp) & (~(dpf->Bmask))) + ((((((t2 - t1) * ey) >> 16) + t1) & (dpf->Bmask >> dpf-> Bshift)) << dpf->Bshift); } while (0);; |
145 | t1 = ((((getAlpha(*c01)(((*c01) & spf->Amask) >> spf->Ashift) - getAlpha(*c00)(((*c00) & spf->Amask) >> spf->Ashift)) * ex) >> 16) + |
146 | getAlpha(*c00)(((*c00) & spf->Amask) >> spf->Ashift)) & (dpf->Amask >> dpf->Ashift); |
147 | t2 = ((((getAlpha(*c11)(((*c11) & spf->Amask) >> spf->Ashift) - getAlpha(*c10)(((*c10) & spf->Amask) >> spf->Ashift)) * ex) >> 16) + |
148 | getAlpha(*c10)(((*c10) & spf->Amask) >> spf->Ashift)) & (dpf->Amask >> dpf->Ashift); |
149 | setAlpha((((t2 - t1) * ey) >> 16) + t1, dp)do { *dp = ((*dp) & (~(dpf->Amask))) + ((((((t2 - t1) * ey) >> 16) + t1) & (dpf->Amask >> dpf-> Ashift)) << dpf->Ashift); } while (0);; |
150 | |
151 | /* Advance source pointers */ |
152 | csax++; |
153 | sstep = (*csax >> 16); |
154 | c00 += sstep; |
155 | c01 += sstep; |
156 | c10 += sstep; |
157 | c11 += sstep; |
158 | /* Advance destination pointer */ |
159 | dp++; |
160 | } |
161 | /* Advance source pointer */ |
162 | csay++; |
163 | csp = (SDL_TYPE *) ((Uint8 *) csp + (*csay >> 16) * src->pitch); |
164 | /* Advance destination pointers */ |
165 | dp = (SDL_TYPE *) ((Uint8 *) dp + d_gap); |
166 | } |
167 | |
168 | |
169 | } else { |
170 | csay = say; |
171 | |
172 | for (y = 0; y < dst_rect->y; y++) { |
173 | csay++; |
174 | sstep = (*csay >> 16) * src->pitch; |
175 | csp = (SDL_TYPE *) ((Uint8 *) csp + sstep); |
176 | } |
177 | |
178 | /* Calculate sstep_jump */ |
179 | csax = sax; |
180 | sstep_jump = 0; |
181 | for (x = 0; x < dst_rect->x; x++) { |
182 | csax++; |
183 | sstep = (*csax >> 16); |
184 | sstep_jump += sstep; |
185 | } |
186 | |
187 | for (y = 0 ; y < dst_rect->h ; y++) { |
188 | sp = csp + sstep_jump; |
189 | csax = sax + dst_rect->x; |
190 | |
191 | for (x = 0; x < dst_rect->w; x++) { |
192 | |
193 | /* Draw */ |
194 | *dp = *sp; |
195 | |
196 | /* Advance source pointers */ |
197 | csax++; |
198 | sstep = (*csax >> 16); |
199 | sp += sstep; |
200 | |
201 | /* Advance destination pointer */ |
202 | dp++; |
203 | } |
204 | /* Advance source pointers */ |
205 | csay++; |
206 | sstep = (*csay >> 16) * src->pitch; |
207 | csp = (SDL_TYPE *) ((Uint8 *) csp + sstep); |
208 | |
209 | /* Advance destination pointer */ |
210 | dp = (SDL_TYPE *) ((Uint8 *) dp + d_gap); |
211 | } |
212 | } |
213 | |
214 | g_free(sax); |
215 | g_free(say); |
216 | } |
217 | |
218 | #undef SDL_TYPE |
219 |