This page provides information on the Caustics rollout under the V-Ray GPU Settings tab.
Overview
V-Ray supports the rendering of Caustics effects based on Photon mapping method. It is still a work in progress and has a few limitations(see below). The supported lights are V-Ray Plane/Disc lights, VRaySun and 3ds Max Direct and Spot lights.
Known limitations:
- From file mode (saving and loading) is not supported.
- Textured lights are not supported.
- Motion-blurred lights are not supported.
- Projector maps for 3ds Max standard lights are not supported.
- Reflection glossiness and Refraction glossiness are not supported.
- Translucent materials - VRayAlsurfaceMtl, VRayFastSSS2 and VRayMtl with translucency set to SSS are not supported.
- IPR doesn’t update Caustics changes
Parameters
Caustics – Turns rendering of caustics on and off.
Search distance units – Specifies the caustics' photon lookup radius units between World (default) and Pixels. When V-Ray needs to render the caustics effect at a given surface point, it searches for a number of photons on that surface in the area surrounding the shaded point (search area). The search area is a circle. Its center is the original photon and its radius is equal to the Search distance value.
Search dist – Specifies the photon lookup radius in pixels.
Max photons – Specifies the maximum number of photons that is considered when rendering the caustics effect on a surface. Smaller values cause fewer photons to be used, and the caustics are sharper but noisier. Larger values produce smoother but blurrier caustics.
Multiplier - Controls the strength of the caustics. It is global and applies to all light sources that generate caustics.
