在主流个人计算机硬件条件下,为加速百万以上三角面片构成的复杂稠密几何模型的绘制速度,综合基于几何的建模与绘制方法GBMR和基于点的建模与绘制方法PBMR的优点,提出了一种同时使用三角面片和点作为基本单元进行对象建模与绘制的点面混合方法.在预处理阶段,对模型表面进行网格分割,存储子块三角面片和顶点点云数据,同时对顶点点云按顶点重要度排序并序列化为线性结构.在实时绘制阶段,进行视相关的裁剪和背面剔除,不同子块按视点距离分别由三角形或点进行绘制.以上过程充分利用图形处理单元GPU,实现了基于GPU的点面混合的对象连续多分辨率绘制,有效地提高了复杂模型的绘制效率.
Presented in this paper is an accelerating hybrid rendering method for complex three-dimensional model using both point and polygon. On current PC hardware, the rendering method, which integrates advantages of both GBMR(graphics-based modeling and rendering) and PBMR(point-based modeling and rendering), works well with complex geometric models, which consist of millions of small triangles. In preprocessing phase, model faces are segmented into regions, then triangles and vertex point clouds of each region are stored together, and simultaneously all vertices are sorted in ascending order according to their important degree, and serialized to linear structure. In real-time rendering phase, view-dependent frustum culling and backface clipping are performed; different regions are rendered using point or triangle according to their distance from viewpoint. The above two phases sufficiently utilize the parallelism nature of GPU (graphic process unit) and efficiently implement a continuous multi-resolution rendering for HPPO (hybrid point and polygon object).