Ptex: Per-Face Texture Mapping for Production Rendering

Figure 1: T. Rex with 2694 faces rendered with Ptex. No explicit UV assignment was used. The largest texture layer, the fine-scale displacements, has 836 million texels stored in a single Ptex file with individual face resolutions ranging from 64 x 64 to 2048 x 2048 texels. No seams are visible across faces, even under close magnification. (©Walt Disney Animation Studios)

Abstract:

Explicit parameterization of subdivision surfaces for texture mapping adds significant cost and complexity to film production. Most parameterization methods currently in use require setup effort, and none are completely general. We propose a new texture mapping method for Catmull-Clark subdivision surfaces that requires no explicit parameterization. Our method, Ptex, stores a separate texture per quad face of the subdivision control mesh, along with a novel per-face adjacency map, in a single texture file per surface. Ptex uses the adjacency data to perform seamless anisotropic filtering of multi-resolution textures across surfaces of arbitrary topology. Just as importantly, Ptex requires no manual setup and scales to models of arbitrary mesh complexity and texture detail. Ptex has been successfully used to texture all of the models in an animated theatrical short and is currently being applied to an entire animated feature. Ptex has eliminated UV assignment from our studio and significantly increased the efficiency of our pipeline.

Access the definitive version of this paper at diglib.eg.org or download the preprint here.

@inproceedings{burley08ptex,
    author      = {Brent Burley and Dylan Lacewell},
    title       = {Ptex: Per-Face Texture Mapping for Production Rendering},
    booktitle   = {Eurographics Symposium on Rendering 2008},
    year        = {2008},
    pages       = {1155--1164}
}