Differential Ray Marching
نویسنده
چکیده
Several participating media rendering algorithms are based on ray marching: they integrate the variations of radiance along the volume covered by the participating media by splitting the path of light into segments and sampling light contribution at each of those segments. This paper revisits the concept of ray marching not as an integration technique, but as the application of a numerical method to solve an initial value differential equation. We present how to apply different numerical methods as ray marching techniques, analyze a wide range of them and study their applicability under different scenarios. Furthermore, we show how each of them improves over traditional ray marching. Any participating media rendering algorithm that is based on ray marching will benefit from the application of our technique by reducing the number of needed samples (and therefore, rendering time) and/or increasing accuracy.
منابع مشابه
A fast phase space method for computing creeping rays
Creeping rays can give an important contribution to the solution of medium to high frequency scattering problems. They are generated at the shadow lines of the illuminated scatterer by grazing incident rays and propagate along geodesics on the scatterer surface, continuously shedding diffracted rays in their tangential direction. In this paper we show how the ray propagation problem can be form...
متن کاملFast Marching Methods - Parallel Implementation and Analysis
Fast Marching represents a very efficient technique for solving front propagation problems, which can be formulated as partial differential equations with Dirichlet boundary conditions, called Eikonal equation:
متن کاملOther marching direction of third order
The main motivation of this work is the problem of compute intersection curve between two surface. The surface/surface intersection, is a fundamental problem in computational geometry and geometric modelling of complex shapes. In general surface intersections, the most commonly used methods include subdivision and marching. Marching-based algorithms begin by finding a starting point on the inte...
متن کاملSLAM and Exploration using Differential Evolution and Fast Marching
The exploration and construction of maps in unknown environments is a challenge for robotics. The proposed method is facing this problem by combining effective techniques for planning, SLAM, and a new exploration approach based on the Voronoi Fast Marching method. The final goal of the exploration task is to build a map of the environment that previously the robot did not know. The exploration ...
متن کاملNumerical Anisotropy Study of a Class of Compact Schemes
We study the numerical anisotropy existent in compact difference schemes as applied to hyperbolic partial differential equations, and propose an approach to reduce this error and to improve the stability restrictions based on a previous analysis applied to explicit schemes. A prefactorization of compact schemes is applied to avoid the inversion of a large matrix when calculating the derivatives...
متن کامل