
Incremental (Stepped) Movement in After Effects
To move position in increments (or a stop-motion movement), we can create a position expression that takes the rounded value divided by our desired increment. Then, we multiply this back by the increment and return the output as our value. This spaces out the movement to coincide with our chosen increment. Together with keyframes set for motion, this expressions helps alter our increment variable to increase or decrease the stop-motion / increment effect.
In this video example using images from Envato Elements, we will just use the X position. We’ll create a variable for our increment, called “inc” in this case. Since we are dealing with position, the X position is 0 in brackets. The Y position can remain unchanged, so we can have it equal to itself, which is a value of 1 in brackets. Then, we return the X and Y position as an array.
var inc = 50
var x = Math.round(value[0]/inc)*inc;
var y = value[1];
[x,y];
You could apply the same formula used for the X position to the Y position (changing to value[1]) to move the Y position in a similar manner.
To do this for a property such as rotation, the expression would be similar for chosing the increment. Create a variable for your spin, in this case called “spin” and apply the same expression. Then, set rotation key frames as desired and enjoy the incremental movement.
var inc = 50
var spin = Math.round(value/inc)*inc;
spin;
To speed or slow the movement, adjust the increment variable.
Enjoying the news? Sign up for the Creative COW Newsletter!
Sign up for the Creative COW newsletter and get weekly updates on industry news, forum highlights, jobs, inspirational tutorials, tips, burning questions, and more! Receive bulletins from the largest, longest-running community dedicated to supporting professionals working in film, video, and audio.
Enter your email address, and your first and last name below!

Responses