Selecting layer with value

[Dan Ebberts]

I’m not sure this is exactly what you’re looking for, but it should give you some ideas:


s = "" + Math.round(effect("Slider Control")("Slider"));
if (s.length < 2) s = "0" + s;
try{
x = thisComp.layer("TITLE_"+s).transform.position[0];
}catch (e){
x = 0;
}
[x,0,0]


the try/catch is there in case your slider goes out of range.

Dan

[Kalleheikki Kannisto]

With your code, if you change the line

Test = 02;
to
Test = "02";

you will have the layer that you have applied the expression to move to the X position value set by the Slider on layer TITLE_02, with position Y and Z values of 0.

Now, I assume you want the (ball) layer to move to the same x position as your selected layer. If so, I’d put a Layer Control on your ball layer and use the following code for ball position:

pos = transform.position;
layer_to_match = effect("Layer Control")("Layer");
x=layer_to_match.transform.position[0];
new_position = [x,pos[1],pos[2]]

[William Allum]

Thanks for the replies Dan and Kalle,

Kalle, you basically summed up my problem with the below:

Test = 02;

to
Test = “02”;

Without the “” I get an error, but with them the expression works fine. The problem is that where the value 02 is I want to add a link to a slider, 02 is a bad example in this case. But say if the slider was set to any number between 1 and 10, the expression would be looking at any layer from TITLE_1 to TTILE_10 based on this value.

[Kalleheikki Kannisto]

Sorry I didn’t think it through: You can’t keyframe a layer control. So it would be a combination of Dan’s method of turning the slider value to a selector plus getting the x position of said layer.

You can simplify the matter by leaving out the leading zero so that the layer name is TITLE_1, TITLE_2, etc.

Thus, the code for ball position based on a slider would be:

pos = transform.position;
num_layers = 3; // highest layer number
layer_num = Math.floor(effect("Slider Control")("Slider"));
target_layer= "TITLE_"+layer_num;
if (layer_num>0 & layer_num<=num_layers) {
x=thisComp.layer(target_layer).transform.position[0];
new_position = [x,pos[1],pos[2]]
} else {
pos}

Dan would write it much neater, though 🙂

[William Allum]

Ah awesome guys… got it to work, thanks so much! Made my day. 🙂