View Full Version : MENTAL RAY: Combining Physical Sun with HDRI

06 June 2012, 01:29 PM
Im for longer time trying to figure out how to correctly combine mental rays Physical Sun (for shadows) and HDRI (for reflections). I tryed many tutorials but always I finish up with same result and probably Im doing something WRONG, but dont know WHAT is it. I always finish up with HDRI reflections but without MR SUN shadow, this is my technique (so Id be like if someone could find the problem):

- I create IBL from the Indirect Lighting menu and assign selected HDRI map.
- I add plane as a ground to reflect shadows. At this point my scene has HDRI reflections and some soft shadow comming from HDRI.
- I create Physical Sun and Sky from the same menu, but in the Hypershade I delete the mr_sky node, so just the Sun lefts. At this point, my scene has correct reflections and the sun shadow reflected on the ground plane, BUT:
- I assign Use Background Shader to this plane, and set it as follows: Specular Color and reflectivity set to 0 and in the Render Stats of the pPlane1 I uncheck the Cast Shadows, Visible in Reflections, Visible in Refractions.
At this point my scene has HDRI reflections and higlights comming from the Sun, BUT no Sun shadow on the ground (soft shadow from ibl only).
Any suggestions ?

Also Id appreciate if you guys tell me how do YOU set up stuff like this to achieve good vehicle renders..

06 June 2012, 07:43 PM
Take a look at the Mental Ray Production shaders. Specifically, the mip_rayswitch nodes. There are a number of tutorials on the net that demonstrate it's use.

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06 June 2012, 07:43 PM
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