Trying to animate only y possition with an expression

[Matt Silverman]

Another solution would be to use the Transform animation preset in AE7 for “Seperate X/Y/Z”. This will make you an effect with three sliders for x/y/z. Then you can link your expression to just the y slider.

-Matt

[Patrick Oneill]

Came across this old thread and posting for other who come across it.

Select the layer you want to link to another layer
Press ALT+SHIFT+= to bring up the expression
For position, you’ll see something like thisComp.layer(“LAYER NAME”).transform.position pop up. This affects BOTH axis.

As Steve said,
position[0] = X
position[1] = Y
position[2] = Z

So, add “position[0]” to the front or “position [1]” to the back of the expression to affect only one axis.

For example, this will affect ONLY the X axis:
[thisComp.layer(“LAYER NAME”).transform.position[0],position[1]]
And this will affect ONLY the Y axis:
[position[0],thisComp.layer(“LAYER NAME”).transform.position[1]]

Hope that helps.