• Adobe After Effects Expressions

  Modifying expression times to layer’s inPoint

  Posted by Adam Levine on March 14, 2016 at 6:51 pm

  Hello! I’ve a serious problem. How can I use ease wizz expression without adding keyframes. I want to set it for time such as layer’s inPoint to inPoint+2 like that. And I’ve used a slider controller to change the eX value of the expression. So I’ve tried so many ways to change the expression. But it didn’t work. Here is that how I changed the expression. Please help me anyone. Master Dan, I think you can give me an idea.

  // Ease and Wizz 2.0.3 : inExpo : All keyframes
// Ian Haigh (https://ianhaigh.com/easeandwizz/)
// Last built: 2012-10-11T16:37:31+11:00

  // some defaults
  var p = 0.8; // period for elastic
  var a = 50; // amplitude for elastic
  var s = 1.70158; // overshoot amount for "back"

  function easeandwizz_inExpo(t, b, c, d) {
  return (t==0) ? b : c * Math.pow(2, 10 * (t/d - 1)) + b;
  }

  function easeAndWizz() {
  var n = 0;
  if (numKeys > 0) {
  n = nearestKey(time).index;
  if (key(n).time > time) { n-- }
  }

  try {
  var key1 = key(n);
  var key2 = key(n+1);
  } catch(e) {
  return null;
  }

  // determine how many dimensions the keyframes need
  var dim = 1; // It's gotta have at least ONE dimension
  try {
  key(1)[1];
  dim = 2;
  key(1)[2];
  dim = 3;
  } catch(e) {}

  t = time - key1.time;
  d = key2.time - key1.time;

  sX = key1[0];
  eX = key2[0] - key1[0];

  if (dim >= 2) {
  sY = key1[1];
  eY = key2[1] - key1[1];

  if (dim >= 3) {
  sZ = key1[2];
  eZ = key2[2] - key1[2];
  }
  }

  if ((time < key1.time) || (time > key2.time)) {
  return value;
  } else {
  val1 = easeandwizz_inExpo(t, sX, eX, d, a, p, s);
  switch (dim) {
  case 1:
  return val1;
  break;
  case 2:
  val2 = easeandwizz_inExpo(t, sY, eY, d, a, p, s);
  return [val1, val2];
  break;
  case 3:
  val2 = easeandwizz_inExpo(t, sY, eY, d, a, p, s);
  val3 = easeandwizz_inExpo(t, sZ, eZ, d, a, p, s);
  return [val1, val2, val3];
  break;
  default:
  return null;
  }
  }
  }

  (easeAndWizz() || value);


  changed to :

  t = time - inPoint;
d = inPoint+2 - inPoint;

  sX = 960;
  eX = 960 - thisComp.layer("ctrl").effect("Value")(1);

  if (dim >= 2) {
  sY = 380;
  eY = 380;

  if (dim >= 3) {
sZ = 0;
eZ = 0;
}
}

  Adam Levine replied 10 years, 4 months ago 2 Members · 4 Replies
• 4 Replies

• 

  Dan Ebberts

  March 14, 2016 at 7:59 pm

  Something like this maybe:

  
v1 = value;
v2 = effect("Slider Control")("Slider");
t1 = inPoint;
t2 = inPoint + 2;
if (time < t1)
v1
else if (time > t2)
v2
else{
d = t2 - t1;
dv = v2 - v1;
t = (time - t1)/d;
v1 + dv*Math.exp(10*(t-1));
}


  Dan
• 

  Adam Levine

  March 14, 2016 at 9:17 pm

  First thank you master Dan for your quick reply. So I changed the expression like this as you said. But it’s not working. 🙁 Sorry for asking. Can you give me a another idea please.

  // Ease and Wizz 2.0.3 : inExpo : All keyframes
// Ian Haigh (https://ianhaigh.com/easeandwizz/)
// Last built: 2012-10-11T16:37:31+11:00

  // some defaults
  var p = 0.8; // period for elastic
  var a = 50; // amplitude for elastic
  var s = 1.70158; // overshoot amount for "back"

  function easeandwizz_inExpo(t, b, c, d) {
  return (t==0) ? b : c * Math.pow(2, 10 * (t/d - 1)) + b;
  }

  function easeAndWizz() {
  var n = 0;
  if (numKeys > 0) {
  n = nearestKey(time).index;
  if (key(n).time > time) { n-- }
  }

  try {
  var key1 = key(n);
  var key2 = key(n+1);
  } catch(e) {
  return null;
  }

  // determine how many dimensions the keyframes need
  var dim = 1; // It's gotta have at least ONE dimension
  try {
  key(1)[1];
  dim = 2;
  key(1)[2];
  dim = 3;
  } catch(e) {}

  sX = value[0];
  eX = thisComp.layer("ctrl").effect("Value")(1);
  t1 = inPoint;
  t2 = inPoint + 2;
  if (time < t1)
  v1
  else if (time > t2)
  v2
  else{
  d = t2 - t1;
  dv = eX - sX;
  t = (time - t1)/d;
  v1 + dv*Math.exp(10*(t-1));
  }

  if (dim >= 2) {
  sY = value[1];
  eY = value[1];

  if (dim >= 3) {
  sZ = value[2];
  eZ = value[2];
  }
  }
  if ((time < key1.time) || (time > key2.time)) {
  return value;
  } else {
  val1 = easeandwizz_inExpo(t, sX, eX, d, a, p, s);
  switch (dim) {
  case 1:
  return val1;
  break;
  case 2:
  val2 = easeandwizz_inExpo(t, sY, eY, d, a, p, s);
  return [val1, val2];
  break;
  case 3:
  val2 = easeandwizz_inExpo(t, sY, eY, d, a, p, s);
  val3 = easeandwizz_inExpo(t, sZ, eZ, d, a, p, s);
  return [val1, val2, val3];
  break;
  default:
  return null;
  }
  }
  }

  (easeAndWizz() || value);
• 

  Dan Ebberts

  March 14, 2016 at 9:51 pm

  That wasn’t meant to be a modification to your expression, it’s an example of a non-keyframed expoIn expression.

  Dan
• 

  Adam Levine

  March 15, 2016 at 5:40 am

  Thank you for your gratitude master Dan. But sorry asking again. Can give me an idea to modify my expression please.

Reply to this Discussion! Login or Sign Up