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View Full Version : Normal Mapping Freakout!!!



Revanto
10-22-2004, 05:15 AM
OK, I'm going nuts here. I need someone to help me out with my normal mapping crisis.

What I want to achieve:

A low res nurbed mesh with a tangent normal map so that it looks like its hi res counterpart so that I can animate it.


What I have or have done:

The hi res mesh in Zbrush with a low res version exported and converted to a LWO. A cage version of the object as a morph. A normal map and displacement map for the low res version of the high res version.


What the problem is:

I can't get the normal mapping or displacement to work in LW. I have a normal displacement plugin and a normal mapping plugin but neither work as they should.

So what are the correct steps for normal displacement and mapping?

Also, I added the greyscale displacement map and all I got were a bunch of ridges. But that's a Zbrush related problem, however.

Any help would be REALLY appreciated.

Cheers,
Revanto

P Jespersen
10-22-2004, 10:32 AM
I do not know if this will help but here is a good tutorial on Zbrush to LW:
http://www.stevewarner.com/Tutorials/zBrush/zBrushTut.html
using this Normal Displacment plug:
http://lynx.aspect-design.de/plugins/normal_displace_info.htm
On the same site is a 16 bit greyscale tiff loader.
You have probably already done all this but it sounds like you missing something.
Hope this helps.

Peter

Peter Jespersen
3D Project Manager
Newtek

Revanto
10-23-2004, 02:59 AM
Yes, I have that tutorial and have all the plugins available for Lightwave. It's just that I'm not getting any proper results as if the normal map wasn't working.

Thanks anyway.

Anyone else?

Cheers,
Revanto

Rory_L
10-23-2004, 04:08 AM
You are using world space normal maps aren`t you? LW doesn`t seem to like the blue object space variety. (Anyone knows how to get them to work in LW please tell me!)

You might try varying the export options in Z-Brush. I find I have to flip the textures on the Y and also on the X, er sometimes :p

Then again, the mapping could be your problem. If you`re applying the normal map to the sub-D, hi-res model there are going to be mapping errors resulting from Lightwave`s linear interpolation of the cage object`s UVs. Test this by setting your render subdivisions to 0 and see if it still looks bad. Furthermore I`d turn off the displacement mapping till you get the normal mapping sorted out, but when you do turn it back on, subdivision order might be something to play with.

Hope some of this helps.

Cheers,

R

Revanto
10-24-2004, 01:20 AM
Yes, I have been using the tangent maps (the blue ones) because the world space ones can't be used in animating yet (I think?).

That might be the core of my problem, actually. I'll give world coordinates a try.

As for the subdivs, it shouldn't be a problem because I tried applying the greyscale displacement map as a bump map and that seamed well. I did flip Vs in Zbrush as Steve Warner suggested in his flash tutorial. The only problem I had with the greyscale displacement/bump map is that I got some sort of weird shading to it (but the UV seams were fine).

Thanks for the help.

Revanto

PS: How's Japan? I miss the place and hope to go back next year.

Rory_L
10-24-2004, 05:52 AM
I hope someone with more brains and experience than I have is reading this, because I don`t consider the following a valid production-useable solution.

What I had was boned characters performing looping animation. As you have found, world space normal maps don`t like boned objects, so what I did was save transformed copied of the models at each frame, then used them as morph targets for an un-boned base mesh. This worked, but I really really wouldn`t want to try this route for anything more than about a second`s looping motion!

Japan`s amazing! You must come back soon. I`d post a photo I took just now of the mikoshi portable shrine that was being hefted through the narrow back streets here on this local festival day, but it`s off topic, isn`t it?

Cheers,

R

Revanto
10-25-2004, 01:01 AM
I suppose if worse comes to worse I can have medium res displacement and a high res bump map. Not the same but what can you do?

If you want, you can email me the pic at revantoATyahooDOTcom. I was there earlier this year for the Sakura and the park (Ueno) was packed! :eek: I have a photo somewhere.

Cheers,
Revanto