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dmarques1177
08-16-2011, 02:09 PM
Hi all

I noticed that while rendering GI in a scene with walls, it blocks out the mapping. Even when I disable cast shadows on the wall geometry and even if that wall geometry only sits behind the objects (like a backdrop image).

Why does it filter out the GI if that's supposed to come from all sides of the scene?

InfernalDarkness
08-16-2011, 08:38 PM
Are you using the Sun/Sky or area lights perhaps?

GI doesn't necessarily come from all directions; your photons must emit from a light or light surface. Only in the case of an HDR or image-based sphere lighting setup will GI come from all directions, based on the luminance data in your image itself.

Or were you perhaps meaning FG? Final Gather and Global Illumination are very different elements of lighting. Perhaps post a render for us to analyze further?

dmarques1177
08-17-2011, 10:05 PM
Are you using the Sun/Sky or area lights perhaps?

GI doesn't necessarily come from all directions; your photons must emit from a light or light surface. Only in the case of an HDR or image-based sphere lighting setup will GI come from all directions, based on the luminance data in your image itself.

Or were you perhaps meaning FG? Final Gather and Global Illumination are very different elements of lighting. Perhaps post a render for us to analyze further?

Sorry I meant the reflections/refractions mapping under GI, using an HDR image for the mapping. It is mapped spherically, but the only way it affects my geometry is by making the backdrop opaque, and I can see this because the opacity of the backdrop directly influences on whether or not I get my mapped reflections. This is strange because I made it one sided and not casting any shadows.

I will post a render tomorrow when I am back at it.

btw when I say I mapped it under GI its because in v-ray there is an environment tab for mapping GI/BG/RF/RFR

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