How do you (engineers at Effect House) create a VGA file for a 3D SDF asset slot that works in VFX pipeline?

I made some VGA files in Unreal to test for the input of the Conform to SDF node and it broke the compile VFX function (didn’t run crashed) is there a set of requirements? What’s the pipeline for creating these SDF assets? Thanks!

Could you upload your .fga file? I have a hunch that it’s malformed because obviously you wouldn’t be able to fit 158,000,000^3 voxels in 120KB. Currently we use Houdini to generate the sample .vf files, although “vector field” is a misnomer for SDF assets because each voxel doesn’t contain a vector, it contains a single scalar value in the R channel that encodes the distance (positive or negative) to a 3D isosurface, which we sample 4 times at slightly different locations in order to estimate the direction that a particle must be moved in order to lie along the surface. Houdini is a very advanced tool that we don’t expect creators to have to learn just to make their own SDF assets, so we’re working on identifying a more accessible pipeline.

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Would it be possible to get some material or examples of using Houdini that can be imported in effect house as an SDF asset? I’m actually interested in using Houdini to generate some advanced particle effects that will live along side some of the effects I’m designing.