We can achieve similar effects, such as low-frequency scattered light illumination from translucent materials, when compared to offline renderers without precomputations. Our technique allows for direct and indirect illuminations from highly scattering translucent materials to be rendered interactively under area lighting at good quality. A uniform set of Poisson disk samples on the translucent objects is resampled and chosen as Translucent Planar Lights (TPLs) and is used to distribute lighting from translucent objects into the LPV by an additional gathering process. Based on experiments, a small number of Poisson disk samples in each voxel are sufficient to produce good results. This allows the direct illumination of the translucent material to be rendered in the ESLPV, and the diffuse indirect illumination of the surrounding scene can be rendered in the LPV. By using a set of sparse translucent Poisson disk samples (TPDS) and diffuse Poisson disk samples (DPDS) for the ESLPV and LPV, illumination can be gathered from area lights effectively. Our voxel illumination uses two existing voxel structures, the Enhanced Subsurface Light Propagation Volumes (ESLPV), which handles the local translucent material appearance and the Light Propagation Volumes (LPV), which handles indirect illumination for the surrounding diffuse surfaces.
In our work, we develop a voxel illumination framework for translucent materials illuminated by area lights. Rendering their indirect illumination produces further challenges. Interactive rendering of translucent materials in virtual worlds has always proved to be challenging. We obtain interactive frame rates, our subsurface scattering results are close to ground truth, and our technique is the first to include interactive transport of emergent light from deformable translucent objects. To build our maps of scattered radiosity, we progressively render the model from different directions using an importance sampling pattern based on the optical properties of the material. Our method requires neither preprocessing nor texture parameterization of the translucent objects. In addition, our method enables easy extraction of virtual point lights for transporting emergent light to the rest of the scene. This enables us to accommodate not only the common distance-based analytical models for subsurface scattering but also directional models. To include changes in subsurface scattering due to changes in the direction of the incident light, we instead sample incident radiance and store scattered radiosity. This is, however, not efficient if we need to store elements of irradiance from specific directions. It is currently a common practice to gain efficiency by storing maps of transmitted irradiance. We demonstrate the performance of our method for several models.Įxisting techniques for interactive rendering of deformable translucent objects can accurately compute diffuse but not directional subsurface scattering effects. The final image is obtained by combining the local and global response.
The illumination map is also used to derive the incident illumination on the vertices which is distributed via the vertex-to-vertex throughput factors to the other vertices. During rendering, the illumination map for the object is computed according to the current lighting situation and then filtered by the precomputed kernels. light shining through the object) is stored as vertex-to-vertex throughput factors for the triangle mesh of the object. In a preprocessing step the impulse response to incoming light impinging at each surface point is computed and stored in two different ways: The local effect on close-by surface points is modeled as a per-texel filter kernel that is applied to a texture map representing the incident illumination. This paper presents a rendering method for translucent objects, in which view point and illumination can be modified at interactive rates.
0 kommentar(er)
