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Lasercade
08-01-2005, 07:03 PM
I've been trying to use TB_NormalMap plugin in Lightave 7.5d on XP to integrate ZBrush2 into some work. Running into some things, and wondering if anyone else has had these problems.

I'm using Steve Warner's tutorial <http://www.stevewarner.com/Tutorials/zBrush/zBrushTut.htm>
and I'm finding that I have to invert the normal maps and texture maps for them to fit the uv's in Lightwave even though I'm using all the settings that Steve has mentioned.

In Layout, the shader seems to be working (at least it doesn't crash Lightwave), but the normal map is not displacing the geometry as I thought it should - it just looks like a bump map on the object.

So... I'm wondering if these are anomalies from the use of 7.5 (i'm not sure if TB's shader only works in 8) or is this what is supposed to happen?

thanks,

mm

toonafish
08-01-2005, 08:22 PM
but the normal map is not displacing the geometry as I thought it should - it just looks like a bump map on the object.


That's what's supposed to happen, you're confusing a normal map with a displacement map.

Lasercade
08-01-2005, 10:35 PM
ok, great.
It seems though that I've seen other examples of this where the geometry IS displaced with just anormal map - guess I was wrong. Good to know this plug-in works in 7.5 as well.

thanks,

mm

toonafish
08-02-2005, 12:48 AM
I think you saw the "normal displacement" plugin. The one that comes with Lightwave Sucks, but there's a very good one from Mathias Wein you can download here:

http://lynx.aspect-design.de/plugins/normal_displace_info.htm

when you're working with Zbrush you can combine both. Use the displacement map for the overall shape and the normal map for the small details. I'm sure there's more info to be found about this at the Zbrush forum.

Lasercade
08-02-2005, 01:06 AM
I guess I'm getting my nomeclature mixed up. So normal mapping is a term that can be applied to both displacement and shading, and these two plug-ins handle different aspects of normal mapping?

So it looks as thought the Mathias Wein's plug-in doesn't work well with animation involving bones? Is this correct, or is there a way to work around it?

thanks,

mm

erikals
08-02-2005, 03:34 PM
As for Normal Maps, I think Lynx's normal map had some problems using bones, but that TB's normal map should work ok. Also TB's normal map should be easier to use with a bump map than Lynx's.

Though this is just on top of my head, can't rem what forum I read it on...

toonafish
08-02-2005, 04:13 PM
I guess I'm getting my nomeclature mixed up. So normal mapping is a term that can be applied to both displacement and shading, and these two plug-ins handle different aspects of normal mapping?

So it looks as thought the Mathias Wein's plug-in doesn't work well with animation involving bones? Is this correct, or is there a way to work around it?

thanks,

mm

Normal mapping is a kind of advanced bumpmap, but besides that it also stores the "smoothing" of the highrez objects geometry. So when you apply a normalmap to a low poly object it almost looks like the highrez. But along the edges you see the difference very clearly, just like with a bumpmap. So for that you have to use actual geometry, this is where you could use a displacement map and set the SubD level high enough so there is something to displace.

A normalmap comes in 2 flavours, world-space ( tangent ) and local. Usualy the world space normal map is used for non-deformed objects and the local for objects you want to deform with bones of whatever. But somehow TB's normalmap shader needs a tangent map and works with bone deformation anyhow, weird but true. You can tell what flavour it is by the colors in the normal map, don't remember exactly but they look different.

A displacement map is a 16 bit greyscale image you can create in Z-brush, there's a 16-bits Tiff import plug available for Lightwave. Check Flay.com if you don't have it already.


Mathias Wein's plug should work just fine with bones, the last time I used it it did.

Lasercade
08-05-2005, 12:35 AM
Hey guys thanks for your answers. I've used a displacement map (with the Lynx plugin) together with TB's normal shader and it works pretty well. Surprisingly, it seems like the lynx plugin is really quick - at the same sub-d level, theres barely and difference in rendertimes with it on or off but it really helps to roughen those edges a little bit.

mm

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