GPU-Driven Real-Time Mesh Contour Vectorization

Abstract

Rendering contours of 3D meshes has a wide range of applications. Previous CPU-based contour rendering algorithms support advanced stylized effects but cannot achieve realtime performance. On the other hand, real-time algorithms based on GPU have to sacrifice some advanced stylization effects due to the difficulty of linking contour elements into stroke curves. This paper proposes a GPU-based mesh contour rendering method which includes the following steps: (1) before rendering, a preprocessing step analyzes the adjacency and geometric information from the 3d mesh model; (2) at runtime, an extraction stage firstly selects contour edges from the 3D mesh model, then the parallelized Bresenham algorithm rasterizes the contour edges into a set of oriented contour pixels; (3) next, Potrace is parallelized to extract (pixel) edge loops from the contour pixels; (4) subsequently, a novel segmentation procedure is designed to partition the edge loops into strokes; (5) finally, these strokes are then converted into 2D strip meshes in order to support rendering with controllable styles. Except the preprocessing step, all other procedures are implemented in parallel on a GPU. This enables our framework to achieve real-time performance for high-resolution rendering of dense mesh models.