Portal Lights are pretty important when rendering interior scenes. They allow the quality and color of the light outside your interior model, inside. Portal lights also offer a great way to manage the noise in the interior spaces. This can have other effects, such as cutting down on render times, because you don’t have to sample so high.
Here, Side FX posts a look at getting started rendering an interior scene that will ultimately use portal lights to bring in light and complete the lighting for the scene.
Mantra is a very capable renderer within Houdini. Mantra has a fairly strong shading language under the hood. With Mantra, you can choose between microPolygon, raytracing or physically based rendering. It is in physically based rendering where you will see the gains using portal lights.
