University of Toronto Technology Overview
CrossShade allows the creation of 3D-looking shaded production drawings from 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.
Further Information
CrossShade is coded in C++. Source and Executable code are available.
Benefits
Automatic shading of concept sketches
Facilitates creation of shaded production drawings from multiple concept sketches
Applications
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.