source: libcaca/trunk/src/cacaball.c @ 616

Last change on this file since 616 was 616, checked in by Jean-Yves Lamoureux, 14 years ago
  • Optimised cacaballs a bit
  • Property svn:keywords set to Id
File size: 5.7 KB
Line 
1/*
2 *  cacaball      metaballs effect for libcaca
3 *  Copyright (c) 2003-2004 Jean-Yves Lamoureux <jylam@lnxscene.org>
4 *                All Rights Reserved
5 *
6 *  $Id: cacaball.c 616 2006-03-15 13:06:25Z jylam $
7 *
8 *  This program is free software; you can redistribute it and/or
9 *  modify it under the terms of the Do What The Fuck You Want To
10 *  Public License, Version 2, as published by Sam Hocevar. See
11 *  http://sam.zoy.org/wtfpl/COPYING for more details.
12 */
13
14#include "config.h"
15
16#if !defined(__KERNEL__)
17#   include <string.h>
18#   include <math.h>
19#   ifndef M_PI
20#       define M_PI 3.14159265358979323846
21#   endif
22#endif
23
24#include "cucul.h"
25#include "caca.h"
26
27/* Virtual buffer size */
28#define XSIZ 256
29#define YSIZ 256
30
31#define METASIZE 128
32#define METABALLS 12
33
34/* Colour index where to crop balls */
35#define CROPBALL 200
36
37static void create_ball(void);
38static void draw_ball(unsigned int, unsigned int);
39
40static unsigned char pixels[XSIZ * YSIZ];
41static unsigned char metaball[METASIZE * METASIZE];
42
43int main(int argc, char **argv)
44{
45    cucul_t *qq; caca_t *kk;
46    unsigned int r[256], g[256], b[256], a[256];
47    float d[METABALLS], di[METABALLS], dj[METABALLS], dk[METABALLS];
48    unsigned int x[METABALLS], y[METABALLS];
49    struct cucul_bitmap *cucul_bitmap;
50    float i = 10.0, j = 17.0, k = 11.0;
51    int p, frame = 0, pause = 0;
52    double frameOffset[360+80];
53    double frameOffset40[360];
54    double frameOffset80[360];
55
56    qq = cucul_init();
57    if(!qq)
58        return 1;
59    kk = caca_attach(qq);
60    if(!kk)
61        return 1;
62
63    caca_set_delay(kk, 20000);
64
65    /* Make the palette eatable by libcaca */
66    for(p = 0; p < 256; p++)
67        r[p] = g[p] = b[p] = a[p] = 0x0;
68    r[255] = g[255] = b[255] = 0xfff;
69
70    /* Create a libcucul bitmap smaller than our pixel buffer, so that we
71     * display only the interesting part of it */
72    cucul_bitmap = cucul_create_bitmap(qq, 8, XSIZ - METASIZE, YSIZ - METASIZE,
73                                       XSIZ, 0, 0, 0, 0);
74
75    /* Generate ball sprite */
76    create_ball();
77
78    for(p = 0; p < METABALLS; p++)
79    {
80        d[p] = cucul_rand(0, 100);
81        di[p] = (float)cucul_rand(500, 4000) / 6000.0;
82        dj[p] = (float)cucul_rand(500, 4000) / 6000.0;
83        dk[p] = (float)cucul_rand(500, 4000) / 6000.0;
84    }
85
86    for(frame = 0; frame<360; frame++) {
87        frameOffset[frame] = frame * M_PI / 60;
88        frameOffset40[frame] = (frame + 40) * M_PI / 60;
89        frameOffset80[frame] = (frame + 80) * M_PI / 60;
90    }
91
92
93    /* Go ! */
94    for(;;)
95    {
96        switch(caca_get_event(kk, CACA_EVENT_KEY_PRESS))
97        {
98            case CACA_EVENT_KEY_PRESS | CACA_KEY_ESCAPE: goto end;
99            case CACA_EVENT_KEY_PRESS | ' ': pause = !pause;
100        }
101
102        if(pause)
103            goto paused;
104
105        frame++;
106        if(frame>=360)
107            frame=0;
108
109        /* Crop the palette */
110        for(p = CROPBALL; p < 255; p++)
111        {
112            int t1, t2, t3;
113            double c1 = 1.0 + sin((double)frameOffset[frame]);
114            double c2 = 1.0 + sin((double)frameOffset40[frame]);
115            double c3 = 1.0 + sin((double)frameOffset80[frame]);
116
117
118            t1 = p < 0x40 ? 0 : p < 0xc0 ? (p - 0x40) * 0x20 : 0xfff;
119            t2 = p < 0xe0 ? 0 : (p - 0xe0) * 0x80;
120            t3 = p < 0x40 ? p * 0x40 : 0xfff;
121            t1/=4; t2/=4; t3/=4;
122
123
124            r[p] = c1 * t1
125                 + c2 * t2
126                 + c3 * t3;
127            g[p] = c1 * t2
128                 + c2 * t3
129                 + c3 * t1;
130            b[p] = c1 * t3
131                 + c2 * t1
132                 + c3 * t2;
133        }
134
135
136        /* Set the palette */
137        cucul_set_bitmap_palette(qq, cucul_bitmap, r, g, b, a);
138
139        /* Silly paths for our balls */
140        for(p = 0; p < METABALLS; p++)
141        {
142            float u = di[p] * i + dj[p] * j + dk[p] * sin(di[p] * k);
143            float v = d[p] + di[p] * j + dj[p] * k + dk[p] * sin(dk[p] * i);
144            u = sin(i + u * 2.1) * (1.0 + sin(u));
145            v = sin(j + v * 1.9) * (1.0 + sin(v));
146            x[p] = (XSIZ - METASIZE) / 2 + u * (XSIZ - METASIZE) / 4;
147            y[p] = (YSIZ - METASIZE) / 2 + v * (YSIZ - METASIZE) / 4;
148        }
149
150        i += 0.011;
151        j += 0.017;
152        k += 0.019;
153
154        memset(pixels, 0, XSIZ * YSIZ);
155
156        /* Here is all the trick. Maybe if you're that
157         * clever you'll understand. */
158        for(p = 0; p < METABALLS; p++)
159            draw_ball(x[p], y[p]);
160
161paused:
162        /* Draw our virtual buffer to screen, letting libcucul resize it */
163        cucul_draw_bitmap(qq, 0, 0,
164                          cucul_get_width(qq) - 1, cucul_get_height(qq) - 1,
165                          cucul_bitmap, pixels + (METASIZE / 2) * (1 + XSIZ));
166        caca_display(kk);
167    }
168
169    /* End, bye folks */
170end:
171    cucul_free_bitmap(qq, cucul_bitmap);
172    caca_detach(kk);
173    cucul_end(qq);
174
175    return 0;
176}
177
178/* Generate ball sprite
179 * You should read the comments, I already wrote that before ... */
180static void create_ball(void)
181{
182    int x, y;
183    float distance;
184
185    for(y = 0; y < METASIZE; y++)
186        for(x = 0; x < METASIZE; x++)
187    {
188        distance = ((METASIZE/2) - x) * ((METASIZE/2) - x)
189                 + ((METASIZE/2) - y) * ((METASIZE/2) - y);
190        distance = sqrt(distance) * 64 / METASIZE;
191        metaball[x + y * METASIZE] = distance > 15 ? 0 : (255 - distance) * 15;
192    }
193}
194
195/* You missed the trick ? */
196static void draw_ball(unsigned int bx, unsigned int by)
197{
198    unsigned int color;
199    unsigned int i, e = 0;
200    unsigned int b = (by * XSIZ) + bx;
201
202    for(i = 0; i < METASIZE * METASIZE; i++)
203    {
204        color = pixels[b] + metaball[i];
205
206        if(color > 255)
207            color = 255;
208
209        pixels[b] = color;
210        if(e == METASIZE)
211        {
212            e = 0;
213            b += XSIZ - METASIZE;
214        }
215        b++;
216        e++;
217    }
218}
219
Note: See TracBrowser for help on using the repository browser.