/
showimage.c
216 lines (196 loc) · 5.45 KB
1
/*
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
showimage: A test application for the SDL image loading library.
Copyright (C) 1997-2012 Sam Lantinga <slouken@libsdl.org>
This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
arising from the use of this software.
Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it
freely, subject to the following restrictions:
1. The origin of this software must not be misrepresented; you must not
claim that you wrote the original software. If you use this software
in a product, an acknowledgment in the product documentation would be
appreciated but is not required.
2. Altered source versions must be plainly marked as such, and must not be
misrepresented as being the original software.
3. This notice may not be removed or altered from any source distribution.
20
21
22
23
*/
#include <stdlib.h>
#include <stdio.h>
24
#include <string.h>
25
26
27
28
#include "SDL.h"
#include "SDL_image.h"
29
30
31
32
33
34
/* #define XPM_INCLUDED and supply picture.xpm to test the XPM inclusion
feature */
#ifdef XPM_INCLUDED
#include "picture.xpm"
#endif
35
36
/* Draw a Gimpish background pattern to show transparency in the image */
37
static void draw_background(SDL_Surface *screen)
38
39
40
41
42
43
44
45
46
47
48
49
50
{
Uint8 *dst = screen->pixels;
int x, y;
int bpp = screen->format->BytesPerPixel;
Uint32 col[2];
col[0] = SDL_MapRGB(screen->format, 0x66, 0x66, 0x66);
col[1] = SDL_MapRGB(screen->format, 0x99, 0x99, 0x99);
for(y = 0; y < screen->h; y++) {
for(x = 0; x < screen->w; x++) {
/* use an 8x8 checkerboard pattern */
Uint32 c = col[((x ^ y) >> 3) & 1];
switch(bpp) {
case 1:
51
dst[x] = (Uint8)c;
52
53
break;
case 2:
54
((Uint16 *)dst)[x] = (Uint16)c;
55
56
break;
case 3:
57
58
59
60
61
62
63
64
65
#if SDL_BYTEORDER == SDL_LIL_ENDIAN
dst[x * 3] = (Uint8)(c);
dst[x * 3 + 1] = (Uint8)(c >> 8);
dst[x * 3 + 2] = (Uint8)(c >> 16);
#else
dst[x * 3] = (Uint8)(c >> 16);
dst[x * 3 + 1] = (Uint8)(c >> 8);
dst[x * 3 + 2] = (Uint8)(c);
#endif
66
67
68
69
70
71
72
73
74
75
break;
case 4:
((Uint32 *)dst)[x] = c;
break;
}
}
dst += screen->pitch;
}
}
76
int main(int argc, char *argv[])
77
{
78
Uint32 flags;
79
SDL_Surface *screen, *image;
80
81
int i, depth, done;
SDL_Event event;
82
#if 0
83
SDL_RWops* rw_ops;
84
#endif
85
86
87
88
/* Check command line usage */
if ( ! argv[1] ) {
fprintf(stderr, "Usage: %s <image_file>\n", argv[0]);
89
return(1);
90
91
92
93
94
}
/* Initialize the SDL library */
if ( SDL_Init(SDL_INIT_VIDEO) < 0 ) {
fprintf(stderr, "Couldn't initialize SDL: %s\n",SDL_GetError());
95
return(255);
96
97
}
98
99
100
101
102
103
104
flags = SDL_SWSURFACE;
for ( i=1; argv[i]; ++i ) {
if ( strcmp(argv[i], "-fullscreen") == 0 ) {
SDL_ShowCursor(0);
flags |= SDL_FULLSCREEN;
continue;
}
105
106
107
108
109
110
111
112
113
114
115
116
#if 0
rw_ops = SDL_RWFromFile(argv[1], "r");
fprintf(stderr, "BMP:\t%d\n", IMG_isBMP(rw_ops));
fprintf(stderr, "GIF:\t%d\n", IMG_isGIF(rw_ops));
fprintf(stderr, "JPG:\t%d\n", IMG_isJPG(rw_ops));
fprintf(stderr, "PNG:\t%d\n", IMG_isPNG(rw_ops));
fprintf(stderr, "TIF:\t%d\n", IMG_isTIF(rw_ops));
/* fprintf(stderr, "TGA:\t%d\n", IMG_isTGA(rw_ops)); */
fprintf(stderr, "PCX:\t%d\n", IMG_isPCX(rw_ops));
#endif
117
/* Open the image file */
118
119
120
#ifdef XPM_INCLUDED
image = IMG_ReadXPMFromArray(picture_xpm);
#else
121
image = IMG_Load(argv[i]);
122
#endif
123
124
125
if ( image == NULL ) {
fprintf(stderr, "Couldn't load %s: %s\n",
argv[i], SDL_GetError());
126
continue;
127
128
129
130
131
132
133
}
SDL_WM_SetCaption(argv[i], "showimage");
/* Create a display for the image */
depth = SDL_VideoModeOK(image->w, image->h, 32, flags);
/* Use the deepest native mode, except that we emulate 32bpp
for viewing non-indexed images on 8bpp screens */
134
135
136
137
138
139
140
if ( depth == 0 ) {
if ( image->format->BytesPerPixel > 1 ) {
depth = 32;
} else {
depth = 8;
}
} else
141
142
143
if ( (image->format->BytesPerPixel > 1) && (depth == 8) ) {
depth = 32;
}
144
145
if(depth == 8)
flags |= SDL_HWPALETTE;
146
147
148
screen = SDL_SetVideoMode(image->w, image->h, depth, flags);
if ( screen == NULL ) {
fprintf(stderr,"Couldn't set %dx%dx%d video mode: %s\n",
149
image->w, image->h, depth, SDL_GetError());
150
continue;
151
}
152
153
154
155
156
157
/* Set the palette, if one exists */
if ( image->format->palette ) {
SDL_SetColors(screen, image->format->palette->colors,
0, image->format->palette->ncolors);
}
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
/* Draw a background pattern if the surface has transparency */
if(image->flags & (SDL_SRCALPHA | SDL_SRCCOLORKEY))
draw_background(screen);
/* Display the image */
SDL_BlitSurface(image, NULL, screen, NULL);
SDL_UpdateRect(screen, 0, 0, 0, 0);
done = 0;
while ( ! done ) {
if ( SDL_PollEvent(&event) ) {
switch (event.type) {
case SDL_KEYUP:
switch (event.key.keysym.sym) {
case SDLK_LEFT:
if ( i > 1 ) {
i -= 2;
done = 1;
}
break;
case SDLK_RIGHT:
if ( argv[i+1] ) {
done = 1;
}
break;
case SDLK_ESCAPE:
case SDLK_q:
argv[i+1] = NULL;
/* Drop through to done */
case SDLK_SPACE:
case SDLK_TAB:
done = 1;
break;
default:
break;
}
break;
case SDL_MOUSEBUTTONDOWN:
done = 1;
break;
case SDL_QUIT:
argv[i+1] = NULL;
done = 1;
break;
default:
break;
}
} else {
SDL_Delay(10);
}
209
}
210
SDL_FreeSurface(image);
211
212
213
}
/* We're done! */
214
SDL_Quit();
215
return(0);
216
}