Amphtml: Animate-in of the rotated layer visible before the start

[StebneRuslan]

Hi, I have a problem with APM story animation. I create a simple story with an image layer. But if I want to rotate the image the image is visible before animation starts.
It is possible to rotate the story layers? Or it’s not supported now?

http://prntscr.com/noqzg8

https://cutnut-tv.cdn.ampproject.org/c/s/cutnut.tv/amp/464fd4b2-f26e-4fd9-ab64-122bde29038f

[torch2424]

Triaging to @newmuis Feel free to re-assign 😄

[newmuis]

The element is supposed to be positioned offscreen, but that's not working; either because of the rotation or because of scaling stuff we do internally. We should address this as an internal implementation detail when applying the first animation frame; the code as listed shouldn't have to change.

[StebneRuslan]

Hi, are there any updates here?

[nainar]

paging @newmuis for an update here. Cutnut asked about this in our partner meeting

[newmuis]

Hi @nainar and @StebneRuslan, this is on our radar; hopefully we'll be able to get around to it soon! @StebneRuslan if you're willing to contribute a fix, we could walk you through what that might look like as well

[newmuis]

/to @johanna08

[johannaperez]

/to @johannaperez

[newmuis]

I was just looking at some other rotation-related stuff, and I wonder if we fail to take the transform-origin into account; if the origin is the center of the element, then how far we have to move it offscreen would be dependent on the size of the element

[yarina2917]

Hi, are there any updates about this issue?

[gmajoulet]

@processprocess I believe you might have fixed this one?

[processprocess]

This needs to be double checked and tested with elements of different heights and widths.
fly-in also has this problem in some aspect ratios #30790