Fine tone control in hardware hatching
Symposium on Non-Photorealistic Animation and Rendering (NPAR) 2002, 53-58.
Crisper rendering of illumination-modulated ink strokes.
Recent advances in NPR have enabled real-time rendering of 3D models shaded with hatching strokes for use
in interactive applications. The key challenges in real-time hatching are to convey tone by dynamically
adjusting stroke density, while controlling stroke size and maintaining frame-to-frame coherence. In this
paper, we introduce two new real-time hatching schemes that leverage recent advances in texture mapping
hardware. Both schemes provide enhanced control of tone, thereby avoiding blending or aliasing artifacts
present in previous systems. The first scheme, which relies on volume rendering hardware, admits the use
of color. The second scheme, which uses pixel shaders, allows per-pixel lighting operations such as
texture modulation. Both schemes run at interactive rates on inexpensive PC graphics cards.
Our per-pixel thresholding scheme creates spatially antialiased black
strokes. The funny thing is that in animations, some people prefer
the blended gray strokes from our original 2001