Feature‐Adaptive and Hierarchical Subdivision Gradient Meshes

Abstract

Gradient meshes, an advanced vector graphics primitive, are widely used by designers for creating scalable vector graphics. Traditional variants require a regular rectangular topology, which is a severe design restriction. The more advanced subdivision gradient mesh allows for an arbitrary manifold topology and is based on subdivision techniques to define the resulting colour surface. This also allows the artists to manipulate the geometry and colours at various levels of subdivision. Recent advances allow for the interpolation of both geometry and colour, local detail following edits at coarser subdivision levels and sharp colour transitions. A shortcoming of all existing methods is their dependence on global refinement, which makes them unsuitable for real‐time (commercial) design applications. We present a novel method that incorporates the idea of feature‐adaptive subdivision and uses approximating patches suitable for hardware tessellation with real‐time performance. Further novel features include multiple interaction mechanisms and self‐intersection prevention during interactive design/editing.

Subdivision Shading for Catmull-Clark and Loop Subdivision Surfaces with Semi-Sharp Creases

“…Our implementation is based on that of [4] and our short paper [7]. It uses C++, OpenGL for graphics, and Qt for window and widget design.…”

“…The present paper extends our short conference paper [7]. The original paper focuses on extending the subdivision shading method of [4] to closed models with (semi-)sharp creases, and is limited to Catmull-Clark subdivision.…”

Selected applications of subdivision surfaces and numerical quadratures for Gregory patches

“…Our implementation is based on that of Bakker et al (2018) and our short paper (Zhou et al, 2022). It uses C++, OpenGL for graphics, and Qt for window and widget design.…”

“…Here we extend our short conference paper (Zhou et al, 2022). The original paper focuses on extending the subdivision shading method of Bakker et al (2018) to closed models with (semi-)sharp creases, and is limited to Catmull-Clark subdivision.…”