Edge flow is the directional arrangement of edges in a 3D model’s mesh, and it is crucial for character animation as it directly influences how the mesh deforms during movement.
Proper edge flow ensures vertices move naturally when rigged, preventing unnatural stretching or tearing—especially critical at joints like elbows, knees, or facial features.
For example, edge loops following muscle lines around the mouth enable smooth lip sync, while loops around knees support realistic bending.
Aligning edge flow with anatomical movement paths during modeling significantly improves animation quality, making characters appear lifelike and fluid.