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wizzackr
08-03-2011, 03:43 PM
Hi Guys, here is the problem: We have a bunch of normal maps, which we were given from another company. In order for these to work nicely with mr the green channel needs to be reversed. ... At least that much is sure, as we tried it in Photoshop for one map.

Now here is the catch: Is there a way to do just that in a shader-network inside of hypergraph? One would assume you could just run the map through a remapRGB node and reverse the curve on the green channel. This does indeed work with vray, but with mr it doesn't. I found a way to reverse them running them through a shadernetwork based on the one posted by headus here (http://www.headus.com.au/samples/norm-MR/graph2.fig.html) Now while this works on primitives it gives one heck of a lot of artifacts when run on a more complex mesh - faces don't show up during FG computation phase etc. So the question is: Is there a simple way to reverse the green channel on an existing normal map which works with mr?

Cheers

oglu
08-03-2011, 04:01 PM
i would do that with a photoshop batch process...
should be the best way...

wizzackr
08-03-2011, 04:06 PM
i would do that with a photoshop batch process...
should be the best way...

not an option, I'm afraid. The normal maps need to be preserved as they are in order to work with multiple rendering engines - and with the flipped green channel they do (as I was told).

wizzackr
08-04-2011, 07:35 AM
anyone any idea? this is rather urgent, sorry for the shameless bump ;)

MasonDoran
08-05-2011, 10:41 AM
just change the Tangent space of the shape node of the geometry.

Then you will not need to invert the green channel.

wizzackr
08-05-2011, 02:05 PM
just change the Tangent space of the shape node of the geometry.

Then you will not need to invert the green channel.

Hey Mason, that didn't give us the same results. You mean changing it to LeftHanded, right?

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