// effect routine

last_letter = numletters - 1;
if (last_letter){
 if (sub_order < 2){
  letter_perc = letter / last_letter;
  if (sub_order == 1) letter_perc = 1 - letter_perc;
 } else if (sub_order < 4){
  my_letter = 2 * letter;
  if (my_letter >= numletters) my_letter = 2 * numletters - my_letter - 2;
  letter_perc = my_letter / last_letter;
  if (sub_order == 3) letter_perc = 1 - letter_perc;
 } else {
  letter_perc = frame / lastsubframe;
 }
 perc = Math.min(1, Math.max(0, 2 * frame / lastsubframe - letter_perc));
} else perc = frame / lastsubframe;
if (reverse_sub_effect == true) perc = 1 - perc;
angle = 44 / 7 * perc;
rota = 360 * perc;
tz = 100 + Math.cos(angle / 2) * 100;
ty = - Math.sin(angle / 2) * 100;
if (use_alpha) alpha = 100 * perc;
xrotate = rota;
yrotate = rota * (y_rotations - 1);
zrotate = rota * (z_rotations - 1);








