Quick Tip: Retopo and optimize assets with UVs in Houdini

Houdini 20 Introduced a Quad Remesher, lets take advantage of it and optimize this rock scan and keep the UV’s.

We begin by importing the asset and scaling it to the correct size. Next, we add a PolyReduce node to reduce the polygon count to a level the QuadRemesh node can handle. Since this node is still in beta, I recommend feeding it a reasonable number of polygons to achieve the best and fastest results.

Then, we drop a QuadRemesh node and connect it, adding a Clean node before it to ensure our mesh is clean. Tweak the settings until we achieve the desired result. If the resulting mesh has errors or holes, the input geometry likely needs adjustment. Thankfully, we can simply go back to the PolyReduce node and modify the polygon count or settings.

At this stage, we should have a quad version of our original messy asset to work with. However, we’ll notice that all UVs are now gone. To restore them, we turn to Houdini Labs. If you haven’t got it installed yet, I highly recommend doing so. With Houdini Labs installed, we search for the Labs UV Transfer node, add it to the chain, and connect our remeshed asset to the Target input and the high-poly asset to the Source input.

This process will give us a cleaner version of our original asset with good topology and UVs transferred as accurately as possible, despite the differences in the meshes.