基于高度差求交的点元表面的光线跟踪算法  

A Ray Tracing Method of Splat-Based Surface Using Height Difference Intersection

作　　者：蔡鹏[1,2] 师平[1,2] 范月圆[1,2] CAI Peng;SHI Ping;FAN Yueyuan(Aeronautical Engineering Institute, Jiangsu Aviation Technical College, Zhenjiang Jiangsu 212134, China;Zhenjiang Key Laboratory of UAV Application Technology, Jiangsu Aviation Technical College, Zhenjiang Jiangsu 212134, China)

机构地区：[1]江苏航空职业技术学院航空工程学院,江苏镇江212134 [2]江苏航空职业技术学院镇江市无人机应用创新重点实验室,江苏镇江212134

出　　处：《图学学报》2017年第4期489-496,共8页Journal of Graphics

基　　金：国家自然科学基金项目(60825203;U0935004)

摘　　要：针对点元表面的光线跟踪方法存在轮廓和尖锐部分绘制效果差等缺点,提出基于高度差求交的点元表面光线跟踪方法。通过融合光线上迭代点与点元面片投影之间距离,计算迭代点到相应点元表面的高度差函数,并以高度差为步长进行点元表面交点的迭代计算。高度差函数符合点元表面上点元融合部分的几何特征。算法结果表明,在点元表面轮廓和尖锐部分光线跟踪产生的图像质量高,且收敛性好、计算成本低。The main drawbacks of current ray tracing methods for splat-based surface are coarse rendering effects in the parts of silhouettes and sharp features.A ray tracing method for splat-based surface is proposed based on the high computation function defined by blending projective distances between the point of ray and the corresponding splats.And the height difference is used as step length to compute iteratively intersection.The height difference function is closed to geometric features of splat-based surface.Experiment results show that the method has good rendering quality in the parts of silhouettes and sharp features,and high convergence rate as well as low computation cost.

关 键 词：点元表面 高度差 求交 隐式曲面 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]