* Optimised cacaballs a bit

src/cacaball.c

@@ -49,6 +49,9 @@ int main(int argc, char **argv)
     struct cucul_bitmap *cucul_bitmap;
     float i = 10.0, j = 17.0, k = 11.0;
     int p, frame = 0, pause = 0;
+    double frameOffset[360+80];
+    double frameOffset40[360];
+    double frameOffset80[360];
 
     qq = cucul_init();
     if(!qq)
@@ -80,6 +83,13 @@ int main(int argc, char **argv)
         dk[p] = (float)cucul_rand(500, 4000) / 6000.0;
     }
 
+    for(frame = 0; frame<360; frame++) {
+	frameOffset[frame] = frame * M_PI / 60;
+	frameOffset40[frame] = (frame + 40) * M_PI / 60;
+	frameOffset80[frame] = (frame + 80) * M_PI / 60;
+    }
+
+
     /* Go ! */
     for(;;)
     {
@@ -93,26 +103,36 @@ int main(int argc, char **argv)
             goto paused;
 
         frame++;
+	if(frame>=360)
+	    frame=0;
 
         /* Crop the palette */
         for(p = CROPBALL; p < 255; p++)
         {
             int t1, t2, t3;
-            t1 = p < 0x40 ? 0 : p < 0xc0 ? (p - 0x40) * 0x20 : 0xfff;
+            double c1 = 1.0 + sin((double)frameOffset[frame]);
+	    double c2 = 1.0 + sin((double)frameOffset40[frame]);
+	    double c3 = 1.0 + sin((double)frameOffset80[frame]);
+
+
+	    t1 = p < 0x40 ? 0 : p < 0xc0 ? (p - 0x40) * 0x20 : 0xfff;
             t2 = p < 0xe0 ? 0 : (p - 0xe0) * 0x80;
             t3 = p < 0x40 ? p * 0x40 : 0xfff;
-
-            r[p] = (1.0 + sin((double)frame * M_PI / 60)) * t1 / 4
-                 + (1.0 + sin((double)(frame + 40) * M_PI / 60)) * t2 / 4
-                 + (1.0 + sin((double)(frame + 80) * M_PI / 60)) * t3 / 4;
-            g[p] = (1.0 + sin((double)frame * M_PI / 60)) * t2 / 4
-                 + (1.0 + sin((double)(frame + 40) * M_PI / 60)) * t3 / 4
-                 + (1.0 + sin((double)(frame + 80) * M_PI / 60)) * t1 / 4;
-            b[p] = (1.0 + sin((double)frame * M_PI / 60)) * t3 / 4
-                 + (1.0 + sin((double)(frame + 40) * M_PI / 60)) * t1 / 4
-                 + (1.0 + sin((double)(frame + 80) * M_PI / 60)) * t2 / 4;
+	    t1/=4; t2/=4; t3/=4;
+
+
+            r[p] = c1 * t1
+                 + c2 * t2
+                 + c3 * t3;
+            g[p] = c1 * t2
+                 + c2 * t3
+                 + c3 * t1;
+            b[p] = c1 * t3
+                 + c2 * t1
+                 + c3 * t2;
         }
 
+
         /* Set the palette */
         cucul_set_bitmap_palette(qq, cucul_bitmap, r, g, b, a);