showanim.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
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
/*
showanim: A test application for the SDL image loading library.
Copyright (C) 1997-2019 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.
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include "SDL.h"
#include "SDL_image.h"
/* Draw a Gimpish background pattern to show transparency in the image */
static void draw_background(SDL_Renderer *renderer, int w, int h)
{
SDL_Color col[2] = {
{ 0x66, 0x66, 0x66, 0xff },
{ 0x99, 0x99, 0x99, 0xff },
};
int i, x, y;
SDL_Rect rect;
rect.w = 8;
rect.h = 8;
for (y = 0; y < h; y += rect.h) {
for (x = 0; x < w; x += rect.w) {
/* use an 8x8 checkerboard pattern */
i = (((x ^ y) >> 3) & 1);
SDL_SetRenderDrawColor(renderer, col[i].r, col[i].g, col[i].b, col[i].a);
rect.x = x;
rect.y = y;
SDL_RenderFillRect(renderer, &rect);
}
}
}
int main(int argc, char *argv[])
{
SDL_Window *window;
SDL_Renderer *renderer;
IMG_Animation *anim;
SDL_Texture **textures;
Uint32 flags;
int i, j, w, h, done;
int current_frame, delay;
SDL_Event event;
/* Check command line usage */
if ( ! argv[1] ) {
SDL_Log("Usage: %s [-fullscreen] <image_file> ...\n", argv[0]);
return(1);
}
flags = SDL_WINDOW_HIDDEN;
for ( i=1; argv[i]; ++i ) {
if ( SDL_strcmp(argv[i], "-fullscreen") == 0 ) {
SDL_ShowCursor(0);
flags |= SDL_WINDOW_FULLSCREEN;
}
}
if (SDL_Init(SDL_INIT_VIDEO) == -1) {
SDL_Log("SDL_Init(SDL_INIT_VIDEO) failed: %s\n", SDL_GetError());
return(2);
}
if (SDL_CreateWindowAndRenderer(0, 0, flags, &window, &renderer) < 0) {
SDL_Log("SDL_CreateWindowAndRenderer() failed: %s\n", SDL_GetError());
return(2);
}
for ( i=1; argv[i]; ++i ) {
if ( SDL_strcmp(argv[i], "-fullscreen") == 0 ) {
continue;
}
/* Open the image file */
anim = IMG_LoadAnimation(argv[i]);
if (!anim) {
SDL_Log("Couldn't load %s: %s\n", argv[i], SDL_GetError());
continue;
}
w = anim->w;
h = anim->h;
textures = (SDL_Texture **)SDL_calloc(anim->count, sizeof(*textures));
if (!textures) {
SDL_Log("Couldn't allocate textures\n");
IMG_FreeAnimation(anim);
continue;
}
for (j = 0; j < anim->count; ++j) {
textures[j] = SDL_CreateTextureFromSurface(renderer, anim->frames[j]);
}
current_frame = 0;
/* Show the window */
SDL_SetWindowTitle(window, argv[i]);
SDL_SetWindowSize(window, w, h);
SDL_ShowWindow(window);
done = 0;
while ( ! done ) {
while ( 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;
}
}
/* Draw a background pattern in case the image has transparency */
draw_background(renderer, w, h);
/* Display the image */
SDL_RenderCopy(renderer, textures[current_frame], NULL, NULL);
SDL_RenderPresent(renderer);
if (anim->delays[current_frame]) {
delay = anim->delays[current_frame];
} else {
delay = 100;
}
SDL_Delay(delay);
current_frame = (current_frame + 1) % anim->count;
}
for (j = 0; j < anim->count; ++j) {
SDL_DestroyTexture(textures[j]);
}
IMG_FreeAnimation(anim);
}
SDL_DestroyRenderer(renderer);
SDL_DestroyWindow(window);
/* We're done! */
SDL_Quit();
return(0);
}