提出一种采用图形加速的三角网格模型实时切分的方法。针对传统的三角网格实时切分方法普遍效率不高的问题,提出利用Open GL的拾取机制的快速、有效,将屏幕曲线映射到模型上,得到切分边缘的三角面片。并利用网格的AIF(Adjacency and Inc...提出一种采用图形加速的三角网格模型实时切分的方法。针对传统的三角网格实时切分方法普遍效率不高的问题,提出利用Open GL的拾取机制的快速、有效,将屏幕曲线映射到模型上,得到切分边缘的三角面片。并利用网格的AIF(Adjacency and Incidence Framework)数据结构和当前图像场景的视角矩阵优化网格模型交线生成追踪过程。然后将相交的三角面片重新三角化,构建新的拓扑结构。最后分离模型,实现模型的快速切分。实验结果表明,该方法能够快速有效地完成模型的实时切分。展开更多
A layered three-dimensional noalinear numerical model was constructed to simulate the generation and propagation of interanal tides over the continental slope. The simulation was split into external mode computation (...A layered three-dimensional noalinear numerical model was constructed to simulate the generation and propagation of interanal tides over the continental slope. The simulation was split into external mode computation (EMC) and internal mode computation (IMC) to minimize the computational load.IMC was carried out once afte EMC was implemented N time. As to EMC, a semi-implicit numerical scheme was applied in such a way that the pressure gradient terms and the velocity divergence terms were discretized semi-implicitly, but the other terms were discretized explicitly. Eulerian-Lagrangian explicit discretization are applied to the convective terms simultaneously. As a result, the stability of EMC did not depend on the wave celerity and time step was not limited by the CFL condition. More than that, use of the conjugate gradient accelerated Jacobi method further improved the computational efficiency of the model.展开更多
文摘提出一种采用图形加速的三角网格模型实时切分的方法。针对传统的三角网格实时切分方法普遍效率不高的问题,提出利用Open GL的拾取机制的快速、有效,将屏幕曲线映射到模型上,得到切分边缘的三角面片。并利用网格的AIF(Adjacency and Incidence Framework)数据结构和当前图像场景的视角矩阵优化网格模型交线生成追踪过程。然后将相交的三角面片重新三角化,构建新的拓扑结构。最后分离模型,实现模型的快速切分。实验结果表明,该方法能够快速有效地完成模型的实时切分。
文摘A layered three-dimensional noalinear numerical model was constructed to simulate the generation and propagation of interanal tides over the continental slope. The simulation was split into external mode computation (EMC) and internal mode computation (IMC) to minimize the computational load.IMC was carried out once afte EMC was implemented N time. As to EMC, a semi-implicit numerical scheme was applied in such a way that the pressure gradient terms and the velocity divergence terms were discretized semi-implicitly, but the other terms were discretized explicitly. Eulerian-Lagrangian explicit discretization are applied to the convective terms simultaneously. As a result, the stability of EMC did not depend on the wave celerity and time step was not limited by the CFL condition. More than that, use of the conjugate gradient accelerated Jacobi method further improved the computational efficiency of the model.