Hello,

I am trying to get a character to dissolve in Unreal from Houdini and I am finding it quite hard to find a way to go about this. The thing which is tripping me up is that the dissolving effect HAS to happen in Houdini, not in Unreal. I am thinking vertex animation is the way to go since Alembic does NOT like deforming surfaces at all.

https://imgur.com/a/49gS55s [imgur.com] (image with character)


Here is an example of what I am trying to transplant into Unreal. I dissolve the model using a color map and a delete node (delete by expression).

Now, the main problem I am having is getting the thing into an Unreal vertex animation. Whenever I try to create a vertex animation using online tutorials something goes wrong and the whole thing doesn't work. The closest I have gotten is using an example .hip to try to run through the workflow on a prebuilt system. The results are below:

https://imgur.com/a/49gS55s [imgur.com] (image with fracturing pigs)

The pink pig is mine while the white one is a premade one that came with the file. Notice how mine is completely off but the workflow is correct. I narrowed this down to the min/max bounds since all of the vertex faces seem to fit correctly into the individual chunks but the chunks are in the incorrect places.



How do I get correct coordinates? Am I doing something wrong in this regard? Should I use a fluid or a rigid vertex animation for the character?

I am curious if this is the best way of dissolving the character. If there's a more intuitive method it would be great to know about it.

Thanks in advance,
Arjan

Hey Arjan. In your test you're showing the rigid export but for what you're trying to do you probably want to use the fluid export which will allow each triangle to shrink and disappear (or just disappear).

Based on your effect you might want to try doing that directly in UE4 with an opacity map and animating the threshold.

Mike

Hey,

I've decided to just go ahead and use the opacity option in Unreal. Thanks for you advice!

Thanks,

Arjan