Getting Started With Portal Lights in Houdini Mantra

This video will demonstrate how to add additional light to a scene using geometry. In this case, the geometry is a window from a scene which you can download from We’ll extract the windows into separate geometry and then using the Portal Light tool, convert them into a light source. With a camera placed and a Mantra PBR ROPcreated, we’re ready to render/fine-tune the rendered image and reduce the noise by tweaking values of Max Ray Samples, Noise Level, enable Indirect Sample Limits, optimize Reflect and Refract limits, Pixel Samples and Sampling Quality. We compare the differences between using a Portal Light to light the scene, and using just Environment Light, because Portal Lights are Environment Lights with a Portal Geometry parameter option.

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