Beyond Pixels: Illustration with Vector Graphics

Abstract

This report presents a novel vector rendering pipeline that allows us to easily break the pixel barrier and create high-quality illustrations. Recently, most graphic research has been directed towards rendering pixel images that appear realistic. In contrast, we investigate the generation of vector graphic illustrations using non-photorealistic techniques such as line rendering and Gooch shading. By combining vector output from both shading and line rendering of 3D models we create high-quality illustrations that can directly be used in print reproduction. Our approach uses a vector graphic pipeline that tracks multiple attributes of strokes and uses them for stylization. This allows to have multiple layers of line rendering such as different stroke types or visible and hidden parts of strokes, each treated differently according to specific stylization rules. Using high quality vector graphics (as opposed to pixel renditions) for representing illustration is essential, in particular, in the print reproduction process. Foremost, vector graphics can be reproduced at any desired resolution; they do not suffer from the resolution dependence of pixel images. In addition, only vector graphics can capture fine details accurately while maintaining a reasonable file size. Finally, vector graphics do not need to be half-toned when printed as long as spot colors are used. Even if some layers of the image use, e. g., shading, only those parts of the vector graphic need to be half-toned that actually do not make use of the available spot colors. Thus, we can combine both shading and line layers without compromising print quality.