Differentiable Shadow Mapping for Efficient Inverse Graphics

Markus Worchel, Marc Alexa

Abstract: We show how shadows can be efficiently generated in differentiable rendering of triangle meshes. Our central observation is that pre-filtered shadow mapping, a technique for approximating shadows based on rendering from the perspective of a light, can be combined with existing differentiable rasterizers to yield differentiable visibility information. We demonstrate at several inverse graphics problems that differentiable shadow maps are orders of magnitude faster than differentiable light transport simulation with similar accuracy – while differentiable rasterization without shadows often fails to converge.