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HowardM
04-24-2007, 08:15 AM
Hey guys,

Just wondering if theres any new way in 9.2 to do this.
Render a model with faces that arent connected, yet has no smoothing errors?

For example, a sphere that has been broken into several pieces when rendered has smoothing errors and doesnt look like a normal sphere... is there a way now to fake it or tell LW, even though the faces arent connected, to render them as if they were?

cheers!

btw, havent had time the past few months to open LW at home, so I have no idea what this new bad boy can really do!

jameswillmott
04-24-2007, 08:32 AM
Yes. You can use a normal map to force the polygons to look smooth even if they are all unwelded.

I think. :)

HowardM
04-24-2007, 08:34 AM
hehe can someone test this for me please?

and can this be done pre 9.0? :)

dpont
04-24-2007, 09:19 AM
But you should use Normal Map in "Object Space",
because in "Tangent Space" it is discontinuous.
45651

Denis.

jameswillmott
04-24-2007, 09:19 AM
Proof of concept.

This uses Object space normal maps, but unless your object isn't going to rotate you'll have to use Tangent space maps. I'm not sure how to bake the smoothed normals of the sphere to tangent space, but I think someone else here figured out how to do it.

Edit: Denis, why would Tangent space be discontinuous?

dpont
04-24-2007, 09:38 AM
Here is what I mean,
have baked this two maps with Normal Cast node
and Surface Baking Camera,
in "Tangent Space" (Texture space) each poly have almost
the same map but for spot (point) on the edge
of polys, color in the map is "discontinuous",
so faking smoothing with such normal map
is badly rendered on the edge, it seems there's also
another problem in LW Normal node...
"Object Space":
45654

"Tangent Space":
45653

Denis.

jameswillmott
04-24-2007, 09:49 AM
Ah! I see, thank you for explaining that.

dpont
04-24-2007, 10:00 AM
If you want to rotate the sphere with "Object Space",
here is a tranformed version of the nodal tree:
45655

Denis.

jasonwestmas
04-24-2007, 10:17 AM
I think if you make your tangent space Nmap in another app. you can still do this trick using the Tangent Space, Normal Map node.

dpont
04-24-2007, 10:36 AM
Here is another "Tangent Space" map made with
Marvin's NormalMapCreate in Modeler, no difference for me.
Could you show another "Tangent Space" map that
do the trick? I'm curious.

Denis.

jasonwestmas
04-24-2007, 12:12 PM
I usually use the Zbrush Zmapper plugin for Nmaps. Unfortunately LW9 modeler's UVs are creating multiple UV sets for some reason on export. This won't work with ZMapper. I'll have to find another way to create the UVs. Until then. . .

jasonwestmas
04-24-2007, 12:26 PM
Nope, it doesn't work even though the tangent Nmap has no poly seam artifacts. Bummer.

dpont
04-24-2007, 03:40 PM
In another hand, a hi-res "Tangent Space" Nmap baked
with NormalMapCreate or NormalCast node (the last updated version)
could attenuate the edges of polys,
here the simple unwelded sphere with a 2000x1500 image:
45670

Denis.

jasonwestmas
04-24-2007, 03:59 PM
Hmm that's interesting, What data is getting "baked" and where is it getting baked into?

lots
04-24-2007, 09:32 PM
Could you do this without a normal map? Node editor gives you access to normals does it not?.. you could perhaps use a combination of nodes to control the normals at the edge of polys?

Just a thought :)

jameswillmott
04-24-2007, 10:45 PM
You need to be able to explicitly define the normals at each point to give the illusion of a continuous surface, tangent normal maps seem to be the only way to do it so the subpieces can be moved independant;y and rotated while retaining correct shading, but as Denis mentioned you can have problems along the polygon edges.

jasonwestmas
04-24-2007, 11:06 PM
Yes this works fine with James' Object Space node too. Like you guys said, this works well with the object space except when you want to animate rotation of the sphere. Theoretically the tangent space Nmap should just be a blank blue texture map to define absolute smoothness. Blue means no elevation or recession in the normals of course. As Denis pointed out there is something funky going on with the Normal Map Node that won't allow the edges of the polys to be reevaluated with the Tangent Nmap. :eek:

dpont
04-25-2007, 02:56 AM
The "Tangent Space" Nmap can also be optimized,
by saving it in a tga file instead of the jpg I used in
my last sample.
Here a 2000x1500 tga "Tangent" normal map
baked with Normal Cast (near 6Mo) and applied
to the basic unwelded sphere, rendered with mediumAA:
45690

if unwelded polys are separated object/layer
animated with a "kaboom" exploding effect,
the "Object Space" nodal tree with an up/right/forward
transformation could work, but the UV map and
the baking should be done before the
separation.

Denis.

HowardM
04-25-2007, 05:16 AM
really cool guys! thanks for all the tests... so this cant be done pre LW9 though right?

reason i asked was to see if these older shredding tests could now be done with curved objects, no seams! http://www.3dink.com/test.html

this is really great, because now this means you could animate a displacement or other animation on these prebroken objects prior to them breaking, where if you tried in 8, you would see seams in the smoothing....

i really need get LW up and running again and do some tests! :D

cheers!

jasonwestmas
04-25-2007, 09:35 AM
Howard, you can do with with the Marvin Landis plugins and TB normal map plugin which animates Object space Nmaps pretty well, at least better than the Marvin Landis plugs. Tangent Space Nmaps I've only seen rendered in LW9. I'm not so sure how well a displacement would work with an unwelded object, I've never done that.

HowardM
04-27-2007, 04:32 AM
cheers guys!