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piripino
11-27-2005, 01:21 PM
First hi all, i'm new here :wavey:

I have a problem with VRay displacement modifier: i need to displace a wall with a brick pattern 'cause i need close views of it and bump mapping isn't enough.

I applied a VRay displacement mod, turned on 3d mapping because i need to keep edge continuity but when i render all invisible edges of my mesh become black and visible :shock:

http://img450.imageshack.us/img450/5558/displ3id.th.jpg (http://img450.imageshack.us/my.php?image=displ3id.jpg)

Here a version with wireframe view

http://img420.imageshack.us/img420/5704/testdispl030vk.th.jpg (http://img420.imageshack.us/my.php?image=testdispl030vk.jpg)

I tryed with a simple box and everything works, but if i only chamfer an edge or create a hole in it the same problem appears :?

http://img297.imageshack.us/img297/7687/displ5ac.th.jpg (http://img297.imageshack.us/my.php?image=displ5ac.jpg) http://img375.imageshack.us/img375/5257/displ22ae.th.jpg (http://img375.imageshack.us/my.php?image=displ22ae.jpg)

Any idea :surprised

Is VRay displacement only good for grass and carpets or am i missing something?
-Vormav-
11-27-2005, 01:45 PM
Welcome. :)
I don't know that this is true of Vray displacements (true for most forms of displacement), but displacements are usually based on subdivisions, so they follow the same rules: Using a displacement map on an object with non-quad topology (which, judging from the wireframe you posted, is definitely true of your mesh) can produce poor, unpredictable results, just as subdividing the same mesh can. In that case, I would recommend connecting some edges on the outside of the model inside to your windows, and try to get it as close to quads as possible (that kind of edge problem is usually fixed by connecting some edges anyway).
Maybe someone that knows vray can verify if that's true of vray or not?
JayCMiller
11-27-2005, 10:35 PM
thats interesting info -Vormav-
a workaround using 2D displacement is to use shift to put the edges back, but it isn't the same because your just overlapping them and not really connecting the edges.
piripino
11-28-2005, 03:13 PM
Just found and completed this tutorial (http://www.seraph3d.com/bricktut.htm) but this is the author result:

http://www.seraph3d.com/BrickTUT_06.jpg

And this is mine :scream:

http://img476.imageshack.us/img476/1526/tut5fc.jpg
CupOWonton
11-28-2005, 04:55 PM
Which version of Vray are you using?
piripino
11-28-2005, 05:59 PM
1.47.03

Also tested 1.46.10 but i got the same problem
CupOWonton
11-28-2005, 07:25 PM
Chaosgroup.com go there and join the forum.
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