Print at Jan 29, 2022, 10:08:38 AM

Posted by db4tech at Sep 1, 2010, 10:18:25 PM
Re: Simulate sun position and lights/shadows
Hi Emmanuel,

I've just realised why caustics don't render (or appear to render, you'll understand why I said this in a moment) while "Add sunlight" is ticked.

Since the added sunlight is a very distant, bright sphere light, the photons emitted for caustics are being emitted by this source so never reach their destination. That's my theory anyway. smile

On the subject of ibl and sunsky not reflecting with uber, this one is really puzzling me. Found out the only reason my simple math formula produced ibl and sunsky reflections is, because the values as fractions exceeded zero into minus figures. Your math formula is right, sorry I thought it was due to objects becoming to shiny!

As a test:
this.sunflow.parameter("glossyness", (float) 0.0); (very shiny and produces sunsky / ibl reflections)
this.sunflow.parameter("glossyness", (float) 0.00000000000000001); (still very shiny but doesn't produce sunsky / ibl reflections)

Have tried many other values and ideas.
Any > 0 never reflects.

Really wish I could figure this out! sad Uber ibl reflections are clearly visible at all logarithmic values in this image.

Hope you're having a nice week! smile