CrossShade: Automated 3D shading from sketches

CrossShade allows the creation of 3D-looking shaded production drawings from initial concept sketches. We use artist-drawn cross-section lines to automatically infer surface information across the sketch, enabling 3D-like rendering.

The software creates a mathematical formulation of the relationships between cross-section curves and the geometry they aim to convey. These relationships are then used to develop an algorithm for estimating a normal field from cross-section curve networks and other curves present in concept sketches.

Cross-sections function as an aid to both sketch creation and viewer understanding of the depicted 3D shape. In particular, intersections of these curves, or cross-hairs, convey valuable 3D information that viewers compose into a mental model of the sketch. We use this information to estimate the surface normals. Combined with conventional shaders, our normals facilitate the creation of shaded drawings.


  • Automatic shading of concept sketches
  • Facilitates creation of shaded production drawings from multiple concept sketches


  • Two granted patents (US9,405,994, US9,965,843)
  • CrossShade is coded in C++. Source and Executable code are available.




Computer Graphics , Animation , 3D imaging , Software

VPRI Contact

Donna Shukaris

Commercialization Manager
Innovations & Partnerships Office (IPO)
(416) 946-7247

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