Retopology

A high-resolution sculpt or scan typically has millions of unevenly distributed triangles — fine for the static shape, but impossible to rig, UV-unwrap, or edit. Retopology overlays a new, sparser mesh on top of the original, with quads that follow the natural topology of the surface (edge loops around eyes, mouth, joints).

Tools like Blender's Quad Remesher add-on, ZBrush's ZRemesher, Maya's Quad Draw, and standalone packages like TopoGun automate most of the work. Manual retopology is still common for hero characters in film and games.

Retopology matters most for animation, rigging, and sculpting workflows. A retopologized character deforms predictably with bones and blend shapes. A scan straight off a photogrammetry tool does not.

For 3D printing, retopology is usually optional — a triangle soup prints fine as long as it is manifold. You retopologize only if you plan to edit the mesh further (smooth a face, add features, repose a figure).

Retopology is not the same as decimation. Decimation reduces polygon count by simplifying triangles in place; the topology stays a mess, just sparser. Retopology builds new clean topology that does not necessarily match the original triangles one-to-one.