Anchor point moving expression

[MarcoTintori]

Hi, is there a way to set the anchor point to the top of the shape?

(screenshot explanation)

The "LINE" layer is a shape layer (rectangle) that change sizes in relation of how many text lines there are.

With the scale, I want to replicate the trim path effect of a stroke to a rectangle, so its anchor point has to be on the top of the shape.

So I ask you if there is an expression or an option to set the anchor point in a specific point of the shape (that can change sizes).

Thanks a lot

This is the old animation with a stroke

[Mathias Moehl]

Hi,

the easiest way to achieve this is using the Anchor Point Controls of Pins & Boxes, see this tutorial

If you want to write your own expression, to place the anchor at the top left corner, for example, you can write

var sourceRect = sourceRectAtTime(time);
[sourceRect.left,sourceRect.top]

[MarcoTintori]

Thanks a lot.

But with this expression I can only put the anchor point on the top left corner of the shape.

How can I put it in the center top and how can the anchor point itself change position in relation of where I put the shape layer?

In my case I want the anchor point to always be in the center top of the shape even if I had to move, scale etc my object

Thanks

[Mathias Moehl]

The expression to always keep it at the top center will be

var sourceRect = sourceRectAtTime(time); 
[sourceRect.left+sourceRect.width/2,sourceRect.top] 

And again - if you don't want to write your own expression, for any other location you can always use the anchor controls of Pins & Boxes.

[Jarle Leirpoll]

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