mr ccmesh/tessellation

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Hello,
Outputting a polygonal mesh with the mi_rendersubd appends the ccmesh block to the geometry, but the overall tessellation is being regulated by the mental ray ROP. By default this is using “fine length 1 angle 5 all” which goes for the whole scene. (Changing this to grid prevents anything from being put into the .mi, which is a step in the right direction)
However, it would be better not to be specifying a tessellation for the whole scene, rather allowing a per object setting. Unfortunately, applying the tessellation parameters to a Geometry object does nothing in the resulting .mi file.
Even more important is outputting the correct ccmesh tessellation settings, otherwise the ccmesh block isn't really being used correctly.
For example, with a simple cube, the block should be:
ccmesh “name” polygon 6 vertex 24 # {
p 0 1 2 3
p 4 5 6 7
p 8 9 10 11
p 12 13 14 15
p 16 17 18 19
p 20 21 22 23
end ccmesh # }
approximate ccmesh fine angle 5 “name” <—missing

Is there any way to get the approximate ccmesh tessellation appended to the geometry?
Thanks,
Chris
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drexel
Hello,
Outputting a polygonal mesh with the mi_rendersubd appends the ccmesh block to the geometry, but the overall tessellation is being regulated by the mental ray ROP. By default this is using “fine length 1 angle 5 all” which goes for the whole scene. (Changing this to grid prevents anything from being put into the .mi, which is a step in the right direction)
However, it would be better not to be specifying a tessellation for the whole scene, rather allowing a per object setting. Unfortunately, applying the tessellation parameters to a Geometry object does nothing in the resulting .mi file.
Even more important is outputting the correct ccmesh tessellation settings, otherwise the ccmesh block isn't really being used correctly.
For example, with a simple cube, the block should be:
ccmesh “name” polygon 6 vertex 24 # {
p 0 1 2 3
p 4 5 6 7
p 8 9 10 11
p 12 13 14 15
p 16 17 18 19
p 20 21 22 23
end ccmesh # }
approximate ccmesh fine angle 5 “name” <—missing

Is there any way to get the approximate ccmesh tessellation appended to the geometry?
Thanks,
Chris

The next daily build of 11 will have a fix for this.

If you create the approximate settings on the object, these will now be picked up when generating ccmesh primtiives. In addition, the “name” of the ccmesh will be a little more descriptive.

You should be able to try it with the attached .hip file.

Attachments:
mi.hip.gz (11.8 KB)

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Thanks Mark, I'll take a look at the file and grab the new daily build.
Chris
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