Property Filters

Property Filters

Property filters map the instantaneous value (vd.val output) of a property to a new value. They are useful for applying custom logic to the output of a keyframe set or function at a given time.

Usage

class CustomLayer extends vd.layer.Base {
  constructor(startTime, duration, foo, options={}) {
    this.foo = foo
  }
}

CustomLayer.prototype._propertyFilters = {
  ...vd.layer.Base._propertyFilters,
  foo: foo => Math.max(0, Math.min(foo, 1)) // clamp between 0 and 1
}

Now, you can access the value as usual:

const layer = new CustomLayer(0, 3, 2 * Math.random())
console.log(layer.foo)  // This will never exceed 1, regardless of the input to `foo`