Interactive Direct Volume Rendering with Many-light Methods and Transmittance Caching
نویسندگان
چکیده
In this paper we present an interactive global illumination method for Direct Volume Rendering (DVR) based on the many-light approach, a class of global illumination methods which gained much interest recently. We extend these methods to handle transfer function and volume density updates efficiently in order to foster ability of interactive volume exploration. Global illumination techniques accounting for all light transport phenomena are typically computationally too expensive for interactive DVR. Many-light methods represent the light transport in a volume by determining a set of virtual light sources whose direct illumination and single scattering to a view ray approximate full global illumination. Our technique reduces computation caused by transfer function changes by recomputing the contribution of these virtual lights, and rescaling or progressively updating their volumetric shadow maps and locations. We discuss these optimizations in the context of DVR and demonstrate their application to interactive rendering.
منابع مشابه
Parallel Irradiance Caching for Interactive Monte-Carlo Direct Volume Rendering
We use irradiance caching for Monte Carlo direct volume rendering to achieve fast convergence for complex scenes with arbitrary sources of light, and show that our approach achieves up to four times increased convergence rate. We propose a technique to save and reuse the illumination within the volume without preprocessing by utilizing three procedures that run concurrently on a single GPU. The...
متن کاملA Model for Volume Lighting and Modeling
Direct volume rendering is a commonly used technique in visualization applications. Many of these applications require sophisticated shading models to capture subtle lighting effects and characteristics of volumetric data and materials. For many volumes, homogeneous regions pose problems for typical gradient based surface shading. Many common objects and natural phenomena exhibit visual quality...
متن کاملTopology-Caching for Dynamic Particle Volume Raycasting
In this paper we present a volume rendering technique for the ad-hoc visualization of interactive particle systems. We focus on methods for an efficient spatial caching (topology caching) of particles when applying a raycasting approach. Thus, we get a fast reconstruction of the scalar field which is defined by the particles’ entities. The node-cache allows for efficient caching and pre-fetchin...
متن کاملMonte Carlo Methods for Volumetric Light Transport Simulation
The wide adoption of path-tracing algorithms in high-end realistic rendering has stimulated many diverse research initiatives. In this paper we present a coherent survey of methods that utilize Monte Carlo integration for estimating light transport in scenes containing participating media. Our work complements the volume-rendering state-of-the-art report by Cerezo et al. [CPP∗05]; we review pub...
متن کاملA Generalized Framework for Interactive Volumetric Point-Based Rendering
of the Dissertation 2006 Volume Visualization is the process of displaying volumetric data represented as sample points on a regular or irregular 3D grid. The data is currently produced by medical scanners such as MRI, CT, etc, and by numerical methods such as scientific simulations. Techniques that have been proposed for this purpose over the years include direct volume-rendering which seeks t...
متن کامل