Smoothing - Strange artifacts - Simply Maya User Community

# 1 31-01-2012 , 11:24 AM

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Smoothing - Strange artifacts

I modeled this in Lightwave and then imported it into Maya as an obj

I hit 3 key to sub-D it and it looks okay.

But I read that that takes up extra time at render within Vray so I used Mesh/smooth to convert it into
more polygons.

But I get these strange leopard spots all over the object.

What are they? Non planar? Is this a common and therefore easily fixed problem?

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# 2 31-01-2012 , 12:56 PM

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hmm I have seen this when normals sometimes gets locked. Try going to polygon menu > normals > unlock normals.

it can also happen if you have additional poly nodes *usually a side effect of working in polygon proxy mode). In this case you have to go into the hypergraph and separate the smoothed and unsmoothed mesh.

You might try mesh > cleanup to ensure you do not have laminate faces or some kind of non-manifold geometry.

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

Last edited by ctbram; 01-02-2012 at 07:01 AM.

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# 3 31-01-2012 , 04:57 PM

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Try normals/set to face !

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# 4 01-02-2012 , 03:34 AM

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Hi thanks, set normals to face did something, it got rid of the artifacts, but as you see in the picture, the surface become non-smoothed (faceted). Also, the entire car is one object at the moment and when I try to perform set to face for the whole car it freezes Maya (hence I just selected some faces on the roof).

Does Maya have a problem with large poly count? I just noticed that when this object is Sub-D'd the feed-back is laggy. And also the fact that trying to "set to face' the whole thing causes a freeze.

I'm just trying to work out to best way to approach Maya when planning a scene.

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# 5 01-02-2012 , 04:08 AM

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Just because I find this both annoying and strangely fascinating.

You can really see how it conforms to the mesh, that must be some kind of clue to what is going on.

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# 6 01-02-2012 , 04:24 AM

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It seems like 'unlock normals' is the right fix for this.

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# 7 01-02-2012 , 04:56 AM

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Now here's the rub, now that I know how to fix this I'm hit with another issue. How to select all vertices in the object? I thought I could hit the 4 key so that it was a wire-frame, and then draw out a big square around the object so that all the vertices are highlighted. But when I rotate the object I find that vertices on the opposite side are not selected. Holy hell, can it really be this hard to select all vertices in an object? The only solutions online I've found involve mel scripts, really? There must be some easy user friendly way to do this.

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# 8 01-02-2012 , 05:28 AM

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Double click the move tool and a bunch of selection options open up in a hidden menu (such an obvious place for this), there are camera based selection checkboxes in there and a bunch of other things. I drew a lasso around the object and then that revealed a little thing that said "select all". All vertices were then selected. Live and learn.

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# 9 01-02-2012 , 07:00 AM

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Sounds like you have backface culling on.

Display > polygons > backface culling

Now the problem here that I have run into is that this will TOGGLE backface culling on individual objects. So if you have multiple objects you end up chasing your tail because you turn it on for some objects and off for others and it's not obvious what objects have bf culling on or off.

So the following mel command will turn backface culling OFF for all selected objects...

polyOptions -bc

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

Last edited by ctbram; 01-02-2012 at 07:03 AM.

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