3D Scan Retopology: Converting Photogrammetry Scans to Game-Ready Geometry
Learn step-by-step techniques to decimate, retopologize, and bake high-poly photogrammetry scans into optimized low-poly meshes with clean quad topology.
Raw 3D photogrammetry outputs consist of dense, unstructured triangle clouds containing millions of polygons. Transforming these meshes for real-time game engines or interactive applications requires structured retopology.
1. Automated Decimation vs. Manual Quad Retopology
While automated decimation filters reduce triangle counts rapidly, they create irregular topology prone to shading artifacts during deformation. Quad-based retopology using snapping constraints and shrinkwrap modifiers preserves structural edge loops along deformation zones.
2. Normal and Displacement Map Baking Workflow
Transfer high-frequency surface details from the raw million-polygon scan to the retopologized low-poly mesh. Using xNormal or Blender's native Cycles bake engine, project surface normals, ambient occlusion, and cavity maps onto unified UV space.
3. Seam Placement and Delighting Photogrammetry Textures
Photogrammetry textures often contain baked directional lighting shadows. Remove environmental shadow gradients using delighting algorithms or albedo extraction filters in Substance 3D Painter to ensure dynamic lighting reacts correctly in-engine.