Hello,
I just noticed an issue with combining Opacity and Transform3D (storyboards?).
This example https://www.noesisengine.com/xamltoy/8a ... 6cd7017a8b
Line 344, just end it with Totally kills the result. Is this some limitation or a bug?
Thank you!

This is a current limitation of mixing offscreen (Opacity, Effects) and 3D. Offscreen do not support 3D. There is no easy solution for this.

We have plans to implement a "fake" Opacity (that instead of rendering to an offscreen it will propagate the alpha to the children) to help with these scenarios. Please, create a ticket for this feature if you need to.

Sorry for resurrecting this, but this is a bit confusing to me.

If I have opacity on the parent of an element with a 3D transform, the 3D is cancelled. However if I set the Opacity on the 3D transformed element itself, or on one of its children, then it works just fine.

Shouldn't it be irrelevant on what level the opacity is set?

Currently, the implementation of Opacity requires an intermediate render-to-texture step. This step operates in texture space (2D), which prevents the application of 3D effects. As a result, any 3D transformations applied above the node with opacity function as expected.

We plan to address this by introducing a cheaper Opacity effect that doesn't require render to texture.

Was this logged as a bug, or is there an issue # we can track for it?

We noticed the same limitation, and were going to bring it up. Though we can use the work around of keeping the opacity animations below 3D ones, for now.

This isn’t exactly a bug but rather a limitation of how 3D transformations and opacity work at the moment. Opacity requires rendering to an intermediate texture, which is the only mathematically correct way to achieve it. However, this process disrupts any 3D transformations.

The proposed solution is to implement a more efficient opacity method that doesn’t require offscreen rendering. While it won’t be as mathematically accurate as the current approach, it will likely be useful in many scenarios and offer better performance. This wouldn’t replace the existing opacity but would instead provide an alternative.

Feel free to file a ticket for this if you'd like.

Thank you!