Mask in Shape Layer unherit Shape' movement

[carmelo0D45]

Hi everyone,

I was following a tutorial and the problem comes when I add a mask layer (in the shape layer) and put keyframe to leave it in the same place so the text (the shape actually) will be showing up from one side. But the mask layer moves a little bit, like wobblin, it won't stay in the place that it is suppose to be. 

I check the possible solutions but I don't understand how is possible that one person can do it without any problem and it doesn't work with me, in this case. 

[Warren Heaton]

With how After Effects renders things, the Mask of the layer always moves with the Position of the layer.

That type of reveal animation is much easier to create if you use a Track Mask, a Set Matte Effect or a Text Layer.

Since you already have the Position change animated, change the Mask setting from Add to None.  Create a Solid Layer or Rectangle Shape layer directly above the "Spotify" Shape Layer, aligning the right edge of the new layer to the right edge of the green circle.  Then change the Track Mask pop-up for the "Spotify" Shape Layer from Alpha Matte to Alpha Matte Inverted.

[carmelo0D45]

Hi Warren,

Thank you for your time. 
I got it already working as you said, however, it was weird seeing that someone else did it more simple just moving the Mask separetadly in animation mode. It would be awesome if Adobe could do it that way ^^'' 

[Rick Gerard]

Try putting the mask on another layer and using it as a track matte. Trying to do what you are describing all on one layer can get very complicated. Track Matte and Set Matte are used in almost all of my composites. I find it a lot more efficient.

[Warren Heaton · Accepted solution]

As long as the change in pixels of your Mask Shape Left and Mask Shape Right exactly match the change in your X position, you'll get what you're looking to do; however, the easier way to avoid unwanted movement in a Layer Mask is to not do anything that moves the Layer Mask.

If you want to keep everything in one Shape Layer, use the Shape Transform to change Position rather than the Layer Transform.  A Shape Transform renders before a Mask which renders before a Layer Transform.  Although, the tricky part of doing it this way is that the tools used to draw shapes on a Shape Layer are shared with the tools used to draw a Mask on a Layer.

Shape Transform used to animate Position instead of Layer Transform

[carmelo0D45]

Yeah I got it now it's working!!

Thanks a lot!! 😄