Flipping Normals

[arobbert]

The shell modifier works great (thanks nvanherpt and Giovanni). I use VIZ 4 with Vray 1.09. I bring the offending geometry into VIZ 2006 add the Shell modifier, set the in and out to .01 to avoid the coplanar surfaces and collapse the mesh, export back into VIZ 4 as 3ds and viola a mesh that renders perfectly. I'm really surpassed by the size of the models that this works on and it's really fast.

[RErender]

Should work to set the amount to zero and utilize the mat ID's then after collapsing it would be easy to get rid of the double geometry.

[DaForce]

yeah good idea RErender that would work perfectly

[arobbert]

Hey Eric, could please give me a quick rundown on that.

[RErender]

Actually I just tried it and it does not work, I thought the shell modifier was somehow unifying the normals but it doesn't, it just flips the new ones. So if you were to delete the original mesh you'd just end up with the opposite flipped faces.

[studioDIM]

Hi,

If your material is double sided and you turn on "Force Two-Sided" in the rendersettings the reflections should be right.

Best Regards,

Dieter

So i discovered, too.
That works

[tvc15]

When you bring in the autocad file do you have 'unify normals' checked in the dwg/dxf import options dialog box?
Try importing once with it check and once without and see if it makes any difference.
Personally I never import with 'unify normals' checked as it usually makes things worse. Same with Weld and Auto-smooth; do those things in Max after its been imported.

Greg

[nvanherpt]

The shell modifier works great (thanks nvanherpt and Giovanni).

well, it's a solution of last resort. i wouldn't recommend it generally as it multiplies the fact count horrendously.

[MediaDream]

Hi! (first post! )
when I have such problem I use the STL Check modifier (as said above)
to spot the problem on the mesh and use the Normal modifier to flip/unify,
and it works just fine.

the thing I saw is DirectX drivers do not display 2 sided plane (even if you
check the 2 sided checker in the material and force 2 sided in the viewport
configuration), maybe some of you don't use opengl driver and it can cause
this in the viewport (not in the render btw..)

[instinct]

To see both sides of a poly, turn off "Backface Culling" in the objects display properties. Works also in DirectX

Regards,
Thorsten

[MediaDream]

To see both sides of a poly, turn off "Backface Culling" in the objects display properties. Works also in DirectX

Regards,
Thorsten

thank you so much I was searching for this (since I changed to DirectX in the
viewport)