reflected light sources

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well, pbr enables reflected light sources automatically. but how to do this manually for the micropoly and/or raytrace engine?
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either nobody knows/understands what i mean or nobody wants to help actually.
in both ways .. let me know.
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In the older render engines that's called specular

eetu.
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thx for the reply but i'm not exactly sure if you really know what i mean. i'm actually talking about reflections and nothing else. to visualize this i rendered a simple example ( a sphere with a grid shaped area light ) in all 3 engines. the material is the pre-built reflective material that comes with houdini; specular completely disabled - reflections enabled.

http://i26.tinypic.com/28shgz.png [i26.tinypic.com]

as you can see the grid shaped area light is reflected in the pbr render. and this feature is enabled automatically by the pbr. ( documentation says: “PBR automatically enables: …, and reflected light sources.” ).

and now my question again: how to enable this manually for the micropoly and/or raytrace engine?

maybe it's not possible at all for micropoly/raytrace .. but what if i want to disable it for pbr? .. so i guess somewhere is this option and i'm unable to figure it out.

thx in advance again. =]
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good point… i never really noticed this before.

anyone know what exactly PBR is doing to reflect lights?
to a man with only a hammer every problem looks like a nail.
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My guess is PBR supports true geometry based area-lights and all other contexts do not.

To reproduce it you use constant shaded geometry placed where your light is.
www.alan-warren.com
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For the non-pbr engines, you need to add an actual piece of geometry to reflect. This is standard practice with all traditional renderers/engines (not just Mantra) – at least in my experience.
See attached.

Attachments:
testrefl.jpg (74.1 KB)
testrefl.hip (989.1 KB)

Mario Marengo
Senior Developer at Folks VFX [folksvfx.com] in Toronto, Canada.
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thanks mario,

was hoping there might be some secret hidden parameter

it might be nice for future releases to get more of these options built into lights…

check out:
http://www.spot3d.com/vray/help/150SP1/light_params.htm [spot3d.com]

vray lights have options for affect diffuse, affect specular, affect reflections and those are seperate from setting the light to be visible in the render or not…
to a man with only a hammer every problem looks like a nail.
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