int rest_lines = num_lines - draw_lines;
draw_tunnel_range(fb_pixels, xoffs, yoffs, starty, draw_lines, time_msec);
if(rest_lines) {
int rest_lines = num_lines - draw_lines;
draw_tunnel_range(fb_pixels, xoffs, yoffs, starty, draw_lines, time_msec);
if(rest_lines) {