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A Bidirectional Deposition Model of Wax Crayons
Dave Rudolf, David Mould, Eric Neufeld.
Computer Graphics Forum, Vol. 24, No. 1, pp. 27--39, March,
2005. [BibTeX]
Simulating Wax Crayons
Author(s): Dave Rudolf, David Mould, Eric Neufeld.
Proceedings: 11th Pacific Conference on Computer Graphics and Applications (PG'03),
2003.
[BibTeX] 
Abstract:
We present a physically-inspired model of wax crayons,
which synthesizes drawings from collections of userspecified
strokes. Paper is represented by a height-field texture,
and a crayon is modelled with a 2D mask that evolves
as it interacts with the paper. The amount of wax deposition
is computed based on the crayon contact profile, contact
force, and friction. Previously deposited wax is smeared
by crayon action, based on wax softness and contact information.
The distributed wax is rendered using a simplified
Kubelka-Monk model, which approximates light transmittance
and scattering effects.