Artifacts ...

Maya for 3D Printing - Rapid Prototyping

In this course we're going to look at something a little different, creating technically accurate 3D printed parts.

# 1 23-05-2012 , 07:41 PM

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I create a cv curve. Revolve it. Convert Nurbs to Polygons. Delete history. Set my Normals so they’re correct and center my pivot. Now I get this flickering artifact pattern appearing. When I send this object to ZBrush and rotate it around various sections will disappear, as though Backface Culling were on ... which it is not. Whats up ?

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# 2 23-05-2012 , 08:45 PM

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Do you still have the original NURBS surface present?

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# 3 23-05-2012 , 08:50 PM

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If you mean is it occupying the same space ... no. After I convert to Poly's I delete the history, Nurbs surfaces and curves. In this case they'd never be used again.

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# 4 23-05-2012 , 08:57 PM

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Try normals > unlock and also make sure you do not have laminar faces. To check for that select all verts and do a merge with a small tolerance. You can also try doing a clean and check for non-manifold geo, edges with zero length, laminar faces, and faces with zero area.

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# 5 25-05-2012 , 08:29 PM

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Still no luck.

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# 6 26-05-2012 , 09:17 AM

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upload the .ma and I can look at it

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# 7 26-05-2012 , 04:03 PM

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Can I post it to this thread as an attachment or do I have to email you?

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# 8 26-05-2012 , 05:07 PM

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upload as a winzip file...........dave

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# 9 29-05-2012 , 03:50 PM

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I'm on a Mac Pro ... would a zip be ok?

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# 10 29-05-2012 , 03:54 PM

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zip will be fine

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# 11 29-05-2012 , 06:25 PM

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Artifacts

Hope this helps. I kind of remember seeing a post about this, or maybe an online tutorial, but it was a long time ago and now it's reared it's ugly head again.

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# 12 29-05-2012 , 06:33 PM

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lol. Press the "5-key" and tell me what you see? You seem to have had "use all lights" mode turned on that is the "7-key" on your keyboard. Since there are no lights in the scene everything is black. Although I cannot explain the white splotches in your screen grab. That is why I thought you had locked normals.

I think I read you were running on a mac laptop so if pressing the 5-key does not fix things then I am afraid you may have a graphics card / driver issue. Maya, especialy Maya 2010 and up have been very finicky about the hardware they will play nicely with.

Here is the before and after I pressed the 5-key screen shots The third one is with lighting > two-sided lighting unchecked so you can see you have no inner thickness.

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"If I have seen further it is by standing on the shoulders of giants." Sir Isaac Newton, 1675

Last edited by ctbram; 29-05-2012 at 07:28 PM.

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# 13 29-05-2012 , 09:01 PM

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I was aware of this. Yes, all lights is enabled, but try it with a poly primitive (pipe) ... not there.And when I send the poly primitive to ZBrush its fine. Not so with the file you have. It appears as though backface culling is on.

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# 14 29-05-2012 , 10:01 PM

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You have no lights in your scene so you do not want to press the 7-key and use all lights (there are no lights).

Also, there is no culling on. It displays fine once I press the 5-key. If it is not displaying properly on your machine it is likely to be a hardware issue or driver issue as the file opens fine on my system. I opened both the .mb and .ma files and once I pressed the 5-key everthing was fine.

If you have deleted or renamed your maya folder and you open this file and press the 5-key and you are still seeing the artifacts then you most likely are looking at a hardware or driver issue.

-Rick

"If I have seen further it is by standing on the shoulders of giants." Sir Isaac Newton, 1675

Last edited by ctbram; 29-05-2012 at 10:04 PM.

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