why the model change suddenly?And affect the render in maya

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Hi,
I posted this in Technical Discussion forum .But I found that it maybe about the houdini engine for maya.

I trail a grid and get some growing curves.

sweep it with a circle curve and get some growing meshes.
at frame 83: it has 4428 points,the edges are arcs



and at frame 84:it has 4482 points,the edges changed to lines



It does not affect the render in houdini.
But it deos affect the render in maya via houdini engine for maya.

How to fix that ?


Thank you very much!
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When the asset outputs NURBS surfaces, they are converted into polygons. By default, the conversion uses the LOD method to adaptively changes the resolution of the output polygons. This prevents the polygons from being too dense. However, it causes the sudden changes that you're seeing. You could prevent this by simply outputting polygons from the asset. For example, you could
1. If the circle SOP is outputting NURBS curve, then sweeping will produce a NURBS surface. If you change the primitive type to polygons, the result of the sweep will be polygons.
2. Or, you could add a convert SOP to after the sweep. This lets you convert the NURBS surface to polygons manually. This lets you control the options that are used in the conversion. Using “Divisions per Span” will give you more consistent output.

Take a look at the attached HDA for an example.

When I have a chance, I can look into adding a parameter onto the Maya node to control this conversion process.

Attachments:
nurbs_sweep.hda (14.7 KB)

Andrew / アンドリュー
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Yes,It works .Thank you very much.
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