Skip to main content
L
LeoKun1985
Participant
July 22, 2024
Question

Luminence drives effects values

  • July 22, 2024
  • 1 reply
  • 1003 views

Hey AE Users! I’m looking for a creative solution using expressions or by any other means.



Is there a way to drive the value strength of an effect via luminence map?



For example, if “Shape Layer 1” has the effect simple choker, I want the choke matte value to be controlled by the luminance intensity for layer “Gradient Map.”

This topic has been closed for replies.

1 reply

Dan Ebberts
Community Expert
Dan EbbertsCommunity Expert
Community Expert
July 22, 2024

Assuming your gradient map is a comp-sized layer centered in the comp, and you want to sample an area of the gradient under the anchor point of the shape, you could use something like this for the Choke Matte property:

 

r = .5; // sample radius
maxChoke = 50; // max value for Choke Matte

L = thisComp.layer("Gradient Map");
p = transform.position;
c = L.sampleImage(p,[r,r],true,time);
hsl = rgbToHsl(c);
linear(hsl[2],0,1,0,maxChoke)

 

L
LeoKun1985Author
Participant
July 23, 2024

Thanks for the reply, Mr Ebberts. It's close, however not quite what I'm looking for, so I'll see if I can rephrase the original question.
Yes, my gradient map is comp-size. It's a standard  horizontal linear gradient: white to black, from left to right.
I'm looking to use this image map to taper the choke matte strength on an oblong shape.
Is such a thing possible in AE?

L
LeoKun1985Author
Participant
July 24, 2024

Try using the Gradient Ramp layer as a Luminosity Track Matte for an Adjustment layer above the layer you want to choke. Pre-compose all layers and adjust the opacity of the Luma Matte layer or the Matte Choker. 

 


Thanks so much for taking the time to test this out, @Rick Gerard. This setup certainly uses the gradient map, but unfortunatly the outer transparency of the shape and it's unrefinment defeats what I'm trying to accomplish.  I'll have to to figure out another means.

Terms & ConditionsAccessibility statement
Using the community Terms of use Privacy Cookie preferences Do not sell or share my personal information ad choicesAdChoices