Houdini FX Geometry to Unreal Engine

 Due to the short time period, we don't have time to learn all the features inside Unreal Engine,. the tool they have given to us is not really artist-friendly in some cases. It would be faster to get it done using DCC software like Houdini. Here are several tips to send your geometry to Unreal Engine.

There are so many ways to do this. At the moment I will show you with Alembic.

Typical Alembic steps for exporting

1. Setting up path attribute per material or primitives

2. Delete unnecessary attributes

3. ROP Alembic as output, Make sure you are in polyland  It is better to use a deforming kind of exporting instead of transform only. If the are so many paths Unreal might crash and the material assignment would be painful.

On the Unreal Engine side:

1. Simply drag and drop to the content drawer

2. Select geometry cache.

3. Disable flatten track

4. Use 3ds max presets for scene conversion

5. Increase the scale to 100, m to cm. The scene scale must be decided here, not in the level. Otherwise, you will have some problems with your mesh precision

6. Drag and drop to your scene and set all world transformations to 0.

7. Add that actor to the sequencer and put the geometry cache timeline.

To tell if you exporting correctly, You didn't do any post adjustment, and the scene should be matched to another DCC.  

Tips and tricks

1. Avoid Ngons. To fix simply use divide SOP

2. Reduce the polycount as low as possible

3. Delete unnecessary attributes

4. Use Keep state instead of Project Default

5. Keyframe the visibility for unwanted behavior.

6. Export only the necessary frame range.

7. Normal is necessary, it depends on but in some cases, you can simply recompute normal in the UE side.

The point is to make the alembic file size as low as possible. The importing time in UE takes some time not instantaneous like Maya's other DCCs, That's it. I hope this is useful to you.