I am using VRay for maya, In LightRect how can I make it shine parallell rays with distance fall off, so that it only spreads in one direction and not sideways, I know we can turn on NoDecay in the options, but that makes an infinite light, but still spreads sideways?
For the moment, it’s not possible; we don’t have the “directionality” parameter from 3ds Max in just yet, but if it’s urgent I can push its priority a bit higher.
Is the “directionality” similar to a barn door type of control? It will be great that we can have this for Rect Light in Maya. In Arnold, it has lights with barn door control and gobo. From my POV, users are provided with tools to light more like a DP.
You have barn doors attributes for the spot lights in Maya; they work with V-Ray too. For the rectangle light, the directionality parameter is similar, although not exactly the same - f.e. there is no way to make a pure directional beam using just barn doors, but you can do that with the directionality parameter. It is more similar to a grid placed in front of the light to control the spread.
Cool, Vlado. Thanks for the information. I wasn’t looking for pure directional beam with barn doors, but was inspired by taking a DP course and saw how a DP light in real-world with barn doors, scrim, etc. to give soft touch on subjects and control edge softness…Maybe it is faster to achieve/fake the same effects with barn-doored spot light, but was just thinking if it isn’t too hard to implement, might not be a bad idea to have it out-of-box for Rect Light. Or, we can just model those panels and parent them to the light…
vlado would placing an object around the light perimeter (to cast shadow i.e. mimic directional effect) affect the render speed vs the directional parameter?