GPU real time hatching

Abstract

Hatching is a shading technique in which tone is represented by a series of strokes or lines. Drawing using this technique should follow three criteria: the lighting, the object geometry and its material. These criteria respectively provide tone, geometric motif orientation and geometric motif style. We present a GPU real time approach of hatching strokes over arbitrary surfaces. Our method is based on a coherent and consistent model texture mapping and takes into account these three criteria. The triangle adjacency primitive is used to provide a coherent stylization over the model. Our model computes hatching parameter per fragment according to the light direction and the geometry and generates hatching rendering taking into account these parameters and a lighting model. Dedicated textures can easily be created off-line to depict material properties for any kind of object. As our GPU model is designed to deal with texture resolutions, consistent mapping and geometry in the object space, it provides real time rendering while avoiding popping and shower-door effects.