Embroidery Modelling and Rendering

Abstract

Embroidery is a traditional non-photorealistic art form in which threads of different colours stitched into a base material are used to create an image. This thesis presents techniques for automatically producing embroidery layouts from line drawings and for rendering those layouts in real time on potentially deformable 3D objects with hardware acceleration. Layout of stitches is based on automatic extraction of contours from line drawings followed by a set of stitch-placement procedures based on traditional embroidery techniques. Rendering first captures the lighting environment on the surface of the target object and renders it as an image in texture space. Stitches are rendered in this space using a lighting model suitable for threads at a resolution that avoids geometric and highlight aliasing. It is also possible to render stitches in layers to capture the 2.5D nature of embroidery. A filtered texture pyramid is constructed from the resulting texture and applied to the 3D object. Aliasing of fine stitch structure and highlights is avoided by this process. The result is a realistic embroidered image that properly responds to lighting.