Hi there,

I'm working on a basic scene with two area lights, one gi light and one env light. Studio backdrop and main object in the center, and I'm using Mantra PBR.

From what I've seen in the previous tests I did in order to get acquainted with Houdini, whenever I change a parameter, if auto-update is ticked in my Render View, then I see the changes automatically applied to the render.

This time though I'm getting some odd issues. When I tweak one light, I don't see any changes (although Mantra starts re-rendering as if there actually was a change). If I tweak the material, same story, I don't see any changes. The only way to really see what's happening when I tweak values, and by stopping the render and re starting it manually.

Is that a bug or a normal behavior?

Should I post more details about the scene? Perhaps I can post the scene if it's needed in order to figure out what is the issue.

Sometimes IPR has some updating problems, though I've never seen it with lights, I have seen it with materials if I'm tweaking nodes inside the material. When you restart the Render View, it recompiles those materials, which then updates them.

While uploading your scene couldn't hurt, I would send it to SideFX as a bug. I know they're trying to get that all working fine, and would appreciate having a file to test against!

https://www.sidefx.com/index.php?option=com_content&task=view&id=768&Itemid=239 [sidefx.com]