Mercurial > sdl-ios-xcode

comparison XCodeiPhoneOS/Demos/src/happy.c @ 2383:1cfe7fd15dad gsoc2008_iphone

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Happy faces demo (bitmaps)
author Holmes Futrell <hfutrell@umail.ucsb.edu>
date Fri, 18 Jul 2008 20:51:47 +0000
parents
children
comparison
equal deleted inserted replaced
2382:36bcf13ccb48 2383:1cfe7fd15dad
1 /*
2 * happy.c
3 * written by Holmes Futrell
4 * use however you want
5 */
6
7 #include "SDL.h"
8 #include "common.h"
9
10 #define NUM_HAPPY_FACES 100 /* number of faces to draw */
11 #define MILLESECONDS_PER_FRAME 16 /* about 60 frames per second */
12 #define HAPPY_FACE_SIZE 32 /* width and height of happyface (pixels) */
13
14 static SDL_TextureID texture_id = 0; /* reference to texture holding happyface */
15
16 static struct {
17 float x, y; /* position of happyface */
18 float xvel, yvel; /* velocity of happyface */
19 } faces[NUM_HAPPY_FACES];
20
21 /*
22 Sets initial positions and velocities of happyfaces
23 units of velocity are pixels per millesecond
24 */
25 void initializeHappyFaces() {
26 int i;
27 for (i=0; i<NUM_HAPPY_FACES; i++) {
28 faces[i].x = randomFloat(0.0f, SCREEN_WIDTH - HAPPY_FACE_SIZE);
29 faces[i].y = randomFloat(0.0f, SCREEN_HEIGHT - HAPPY_FACE_SIZE);
30 faces[i].xvel = randomFloat(-0.1f, 0.1f);
31 faces[i].yvel = randomFloat(-0.1f, 0.1f);
32 }
33 }
34
35 void render(void) {
36
37 int i;
38 SDL_Rect srcRect;
39 SDL_Rect dstRect;
40
41 /* setup boundaries for happyface bouncing */
42 Uint16 maxx = SCREEN_WIDTH - HAPPY_FACE_SIZE;
43 Uint16 maxy = SCREEN_HEIGHT - HAPPY_FACE_SIZE;
44 Uint16 minx = 0;
45 Uint16 miny = 0;
46
47 /* setup rects for drawing */
48 srcRect.x = 0;
49 srcRect.y = 0;
50 srcRect.w = HAPPY_FACE_SIZE;
51 srcRect.h = HAPPY_FACE_SIZE;
52 dstRect.w = HAPPY_FACE_SIZE;
53 dstRect.h = HAPPY_FACE_SIZE;
54
55 /* fill background in with black */
56 SDL_RenderFill(0, 0, 0, 255, NULL);
57
58 /*
59 loop through all the happy faces:
60 - update position
61 - update velocity (if boundary is hit)
62 - draw
63 */
64 for (i=0; i<NUM_HAPPY_FACES; i++) {
65 faces[i].x += faces[i].xvel * MILLESECONDS_PER_FRAME;
66 faces[i].y += faces[i].yvel * MILLESECONDS_PER_FRAME;
67 if (faces[i].x > maxx) {
68 faces[i].x = maxx;
69 faces[i].xvel = -faces[i].xvel;
70 }
71 else if (faces[i].y > maxy) {
72 faces[i].y = maxy;
73 faces[i].yvel = -faces[i].yvel;
74 }
75 if (faces[i].x < minx) {
76 faces[i].x = minx;
77 faces[i].xvel = -faces[i].xvel;
78 }
79 else if (faces[i].y < miny) {
80 faces[i].y = miny;
81 faces[i].yvel = -faces[i].yvel;
82 }
83 dstRect.x = faces[i].x;
84 dstRect.y = faces[i].y;
85 SDL_RenderCopy(texture_id, &srcRect, &dstRect);
86 }
87 /* update screen */
88 SDL_RenderPresent();
89
90 }
91
92 /*
93 loads the happyface graphic into a texture
94 */
95 void initializeTexture() {
96 SDL_Surface *bmp_surface;
97 SDL_Surface *bmp_surface_rgba;
98 int format = SDL_PIXELFORMAT_ABGR8888; /* desired texture format */
99 Uint32 Rmask, Gmask, Bmask, Amask; /* masks for desired format */
100 int bpp; /* bits per pixel for desired format */
101 /* load the bmp */
102 bmp_surface = SDL_LoadBMP("icon.bmp");
103 if (bmp_surface == NULL) {
104 fatalError("could not load bmp");
105 }
106 /* set white to transparent on the happyface */
107 SDL_SetColorKey(bmp_surface, 1, SDL_MapRGB(bmp_surface->format, 255, 255, 255));
108 SDL_PixelFormatEnumToMasks(format, &bpp, &Rmask, &Gmask, &Bmask, &Amask);
109 /*
110 create a new RGBA surface and blit the bmp to it
111 this is an extra step, but it seems to be necessary
112 is this a bug?
113 */
114 bmp_surface_rgba = SDL_CreateRGBSurface(0, bmp_surface->w, bmp_surface->h, bpp, Rmask, Gmask, Bmask, Amask);
115 SDL_BlitSurface(bmp_surface, NULL, bmp_surface_rgba, NULL);
116
117 /* convert RGBA surface to texture */
118 texture_id = SDL_CreateTextureFromSurface(format, bmp_surface_rgba);
119 if (texture_id == 0) {
120 fatalError("could not create texture");
121 }
122 SDL_SetTextureBlendMode(texture_id, SDL_TEXTUREBLENDMODE_BLEND);
123
124 /* free up allocated memory */
125 SDL_FreeSurface(bmp_surface_rgba);
126 SDL_FreeSurface(bmp_surface);
127 }
128
129 int main(int argc, char *argv[]) {
130
131 SDL_WindowID windowID;
132 Uint32 startFrame;
133 Uint32 endFrame;
134 Uint32 delay;
135 int done;
136
137 /* initialize SDL */
138 if (SDL_Init(SDL_INIT_VIDEO) < 0) {
139 fatalError("Could not initialize SDL");
140 }
141 windowID = SDL_CreateWindow(NULL, 0, 0, SCREEN_WIDTH, SCREEN_HEIGHT,\
142 SDL_WINDOW_OPENGL|SDL_WINDOW_SHOWN|SDL_WINDOW_BORDERLESS);
143
144 SDL_CreateRenderer(windowID, -1, 0);
145
146 initializeTexture();
147 initializeHappyFaces();
148
149 /* main loop */
150 done = 0;
151 while(!done) {
152 startFrame = SDL_GetTicks();
153 SDL_Event event;
154 while (SDL_PollEvent(&event)) {
155 if (event.type == SDL_QUIT) {
156 done = 1;
157 }
158 }
159 render();
160 endFrame = SDL_GetTicks();
161
162 /* figure out how much time we have left, and then sleep */
163 delay = MILLESECONDS_PER_FRAME - (endFrame - startFrame);
164 if (delay < 0) {
165 delay = 0;
166 } else if (delay > MILLESECONDS_PER_FRAME) {
167 delay = MILLESECONDS_PER_FRAME;
168 }
169 SDL_Delay(delay);
170 }
171
172 /* cleanup */
173 SDL_DestroyTexture(texture_id);
174 /* shutdown SDL */
175 SDL_Quit();
176
177 return 0;
178
179 }