Computer-generated graphite pencil rendering of 3D polygonal models

Researchers in non-photorealistic rendering have investigated the display o f three-dimensional worlds using various display models. In particular rece nt work has focused on the modeling of traditional artistic media and style s such as pen-and-ink illustration and watercolor painting. By providing 3D rendering systems that use these alternative display models users can gene rate traditional illustration renderings of their three-dimensional worlds. In this paper we present our graphite pencil 3D renderer We have broken th e problem of simulating pencil drawing down into four fundamental parts: (1 ) simulating the drawing materials (graphite pencil and drawing paper; blen ders and kneaded eraser), (2) modeling the drawing primitives (individual p encil strokes and mark-making to create tones and textures), (3) simulating the basic rendering techniques used by artists and illustrators familiar w ith pencil rendering, and (4) modeling the control of the drawing compositi on. Each parr builds upon the others and is essential to developing the fra mework for higher-level rendering methods and tools. In this paper we prese nt parts 2 3, and 4 of our research. We present non-photorealistic graphite pencil rendering methods for outlining and shading. We also present the co ntrol of drawing steps from preparatory sketches to finished rendering resu lts. We demonstrate the capabilities of our approach with a variety of imag es generated from 3D models.