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Paul_Boland
02-17-2010, 01:45 PM
Hi Folks.

Just two quick questions...

1. Jitter.
I love the Jitter tool. It's a great way to create rough surfaces on stuff like meteors and the likes but one issue I have is that when I use it, it tends to cause tears in the mesh. What I want is to apply Jitter and have it offset the polygons, as it does, but witout seperating points in the process. Is there a way to do this?

2. Textures.
I've been working on some models and have realised that some of the textures I created for each model are named simulary. For example, Model A could have a texture called Dark Metal and Model B could also have a texture called Dark Metal, but both textures, while having the same name, are completely different textures. Is this going to cause me problems if I have both Model A and Model B in the same scene? Should all textures have unique names?

Thanks.

Kuzey
02-17-2010, 02:01 PM
Textures should be fine as long as you have "Edit by Object" selected in the surface editor.


If it's set to scene...all the same surface names will have the same surfaces.

Kuzey

probiner
02-17-2010, 04:15 PM
Search for threads talking of dpont's PolyMove or PartMove.
Here is one of mine (http://www.newtek.com/forums/showthread.php?p=885391#post885391) that i think i was trying to do something like you asked.
Here is one applyed to buildings (http://www.newtek.com/forums/showthread.php?t=101147)

Good Luck

Paul_Boland
02-18-2010, 01:00 PM
Great, thanks for the info, guys, much appreciated.

toby
02-18-2010, 09:14 PM
Jitter should not seperate any points/polygons, but it does lead to massively non-planar polys, that's probably the holes you're seeing. Tripling should fix it.

jin choung
02-19-2010, 02:08 AM
jitter absolutely does not unweld verts.

if you're finding that you're getting unwelded verts after a jitter, it was unwelded BEFORE you jittered.

and yah check if indeed you are running into the issue that toby points out.

jin

archijam
02-19-2010, 02:34 AM
Jitter is great for small changes on a large mesh (the max. distance should be less tha half the shortest distance between to verticies).

Any more than this, and you will start to get crossed geometry, which may appear as tears when rendered.

Also, keep in mind that on a planar surface you can always avoid this by only jittering in one axis. This is of course not possible with a sphere (in your case a planet) potentially resulting in problems.

It also tends to work best on meshes with a more or less even polygon size (depending on what you are aiming for, an even texture in this case). therefore, use tesselated spheres, not polar ones.


Have you thought of using a displacement in layout? In some cases it can give similar effects, but without corrupting your original geometry.

Paul_Boland
02-19-2010, 07:47 PM
Thanks for the additional replies on Jitter. I can assure you that my model mesh has no unwelded points. A meteor starts life as a cube, subdivided so there are four polygons on each side. I then hit TAB to turn on subpatch and with move, rotate and extend, I create a small meteor like object. I then freeze this, creating a polygon mesh. But this is smooth, meteors are not. So I then apply Jitter. It works great, I only apply it to give a small offset on each polygon making it all rough, but sometimes, not always, after Jitter, I have gaps/holes in the mesh and can see through it.

I will turn all my polygons into triangles instead of squares and see if the problem pops up again.

Thanks again, much appreciated.

probiner
02-19-2010, 08:12 PM
Sorry for my post. I pointed you a the completly inverse direction :foreheads
Bad reading

Paul_Boland
02-20-2010, 12:44 PM
No worries. I enjoyed the topic you directed me too.