Table of Contents

This page provides information about the Interactive tab of V-Ray Render Settings in Cinema 4D.


Overview

To use Interactive you must have V-Ray assigned as a render engine. The Interactive tab in the Render Settings window allows you to control the settings of the Interactive Rendering in the VFB. Regardless of the render engine (CPU or GPU), Interactive always uses Brute Force GI engine to calculate the primary and secondary bounces. 


UI Path: ||Render Settings|| > V-Ray > Interactive tab


Shading

Enable Light Cache in Interactive – By default, when rendering in Interactive mode, Brute Force GI is used. This option allows you to use Light Cache GI in Interactive rendering.


Rendering

Max. Render Time (min) –  Since Interactive uses progressive path tracing, it would never stop rendering unless specified otherwise. This option allows the user to specify a maximum render time in minutes.

Max. Paths per Pixel – Allows the user to limit the maximum quality achieved by Interactive, by specifying a maximum number of rays traced for each pixel. Once the specified number has been reached V-Ray stops rendering.

Max. Noise – Specifies the noise threshold for Interactive. Once the threshold is met for a certain part of the image, V-Ray stops sampling it and reassigns rendering power to part of the image that require more sampling.





Performance

The parameters in this section affect the performance of Interactive. Note that the optimal values for a given machine and network configurations may be different from the defaults. The user is encouraged to experiment with these values to find the optimal ones.

CPU Ray Bundle Size – These control the number of rays that are sent to the Interactive render servers for processing when using Interactive. When using distributed rendering, the smaller sizes cause more frequent client/server communication with smaller network packets thus decreasing the speed of the renderer but increasing the interactivity and vice versa. Note that this number is not the exact amount of rays, but is proportional to it. It is not recommended to increase this value beyond 512.

CPU Rays per Pixel – The number of rays that are traced for each pixel during one image pass. The greater the value, the smoother the picture from the very beginning of the rendering with GI. However, interactivity is significantly diminished. Increasing this value also reduces the amount of data transferred from the render servers back to the client machine.

Progressive Rays per Pixel – When enabled, Interactive starts rendering the image with a lower Rays Per Pixel value and then progressively increases it. This allows us to speed up the initial preview of the image.

Undersampling – When enabled, Interactive starts rendering the image at a lower resolution in order to speed up the initial preview. Later the image is rendered at its final resolution.