RAINMAX
for (i = 3; i < (RAINMAX+1)*3; i += 3)
t = rain_pal[(RAINMAX*3+2)];
for (i = (RAINMAX*3+2); i > 5; i -= 3)
vid[i] = 1 + (krandom() % RAINMAX);
vid[k] = (vid[k-SCRW] < RAINMAX) ? 1 + vid[k-SCRW] : 1;