Feature-preserving triangular geometry images for level-of-detail representation of static and skinned meshes

Abstract

Geometry images resample meshes to represent them as texture for efficient GPU processing by forcing a regular parameterization that often incurs a large amount of distortion. Previous approaches broke the geometry image into multiple rectangular or irregular charts to reduce distortion, but complicated the automatic level of detail one gets from MIP-maps of the geometry image. We introduce triangular-chart geometry images and show this new approach better supports the GPU-side representation and display of skinned dynamic meshes, with support for feature preservation, bounding volumes, and view-dependent level of detail. Triangular charts pack efficiently, simplify the elimination of T-junctions, arise naturally from an edge-collapse simplification base mesh, and layout more flexibly to allow their edges to follow curvilinear mesh features. To support the construction and application of triangular-chart geometry images, this article introduces a new spectral clustering method for feature detection, and new methods for incorporating skinning weights and skinned bounding boxes into the representation. This results in a tenfold improvement in fidelity when compared to quad-chart geometry images.

Reducing Memory Requirements for Diverse Animated Crowds

“…Texture space has been found to be useful in several areas in computer graphics such as global illumination ( [Thiedemann et al 2011]) and geometry images ( [Gu et al 2002;Feng et al 2010]), its associated dense space avoids size dependency and topology issues common in vertex representations. In addition, in the case of facial modeling, it has been shown ( [Beier and Neely 1992;Blanz and Vetter 1999]) that using a param- eterized space is author friendly, reduces modeling time required and complexity.…”

Adaptive Geometry Images for Remeshing

“…Yao and Lee [9] decompose a mesh into square GIM charts with different resolutions, each of which is adaptively determined by a local reconstruction error. Feng et al [10] propose geometry images for generating triangular patches based on a curvilinear feature. The feature preserves salient features and supports GPU-based LOD representation of meshes.…”

A Real-Time System for Crowd Rendering: Parallel LOD and Texture-Preserving Approach on GPU

“…Hu et al [8] proposed a parallel algorithm for view-dependent LOD rendering. Feng et al [3] presented a parallel LOD approach for skinned meshes using geometry images. Peng et al [13] presented a method of parallel progressive LOD for rendering massive and complex models interactively.…”

“…, t n } is n triangles. t i is a triple of index pairs, denoted as t i = {(vdx 1 , udx 1 ), (vdx 2 , udx 2 ), (vdx 3 , udx 3 )}, where vdx j (j ∈ [1,3]) is a vertex index in the range of [1, m], and udx j (j ∈ [1,3]) is a texture coordinate index in the range of [1, r].…”

“…2(c-d)). This is because when a bone of the skeleton is bent, the flat region of the static shape around this joint may significantly change to a high curvature region, where more features are demanded [3]. To solve this problem, we collapse an edge by considering the actual shapes of all frames in the motions.…”