Detail control in line drawings of 3D meshes

We address the problem of rendering a 3D mesh in the style of a line drawing, in which little or no shading is used and instead shape cues are provided by silhouettes and suggestive contours. Our specific goal is to depict shape features at a chosen scale. For example, when mesh triangles project into the image plane at subpixel sizes, both suggestive contours and silhouettes may form dense networks that convey shape poorly. The solution we propose is to convert the input mesh to a multiresolution representation (specifically, a progressive mesh), then view-dependently refine or coarsen the mesh to control the size of its triangles in image space. We thereby control the scale of shape features that are depicted via silhouettes and suggestive contours. We propose a novel refinement criterion that achieves this goal and address the problem of maintaining temporal coherence of silhouette and suggestive contours when extracting them from a changing mesh.