[Gothra]

Dear all,

Annoying geometry glitch, any suggestion how to refine that?
Below are the basic procedures of how I modelled the form...











I thought this was a rather "clean" method of modelling this form, but I still encounter the geometry glitch when rendered with the Rhino built-in render and also with Maxwell.
Already tried setting the "Render Mesh Quality" within Rhino to "Smooth & Slower" and "Custom" with finer settings. Still yield similar results.
Can anyone suggest alternative modelling method to avoid this, or any setting I can mess with?

Thanks and best regards,
Gothra

ps. The model is one polysurface rather than separate surfaces.

[polynurb]

sometimes rhino fails to update some meshes,
try forcing it by selecting the object an running _refreshShade command

(-you can also adjust per object mesh settings in the object properties)

if it does not help, here a quick and dirty test procedure:

exlope all and _rebuildEdges on all srfs with a tolerance still acceptable to you. (so if this model has the size of a soap bar, about .01 to .1 mm)

then join back together and see if it is a closed solid once again.

if it is it should render fine...

if it doesn't... feel free to post a link to the .3dm file... sometimes there is a dog in the nurbs

[Gothra]

Thanks Polynurb
Tried doing what you suggested but the glitch still persists.

I would like to post my model here but dunno how, however I have posted it onto the Rhino discussion:
news:<49583b6c@news.mcneel.com>

Its the "Mesh Glitch" thread on the 28th Dec

Sorry for the trouble
Best regards,

Jacky

[polynurb]

hi Jacky,

i think "Jim" in the rhino forum already answered your problem... it is the way controlpoints are distributed in the fillet surface.

It is not really a meshing error, the nurbs are the origin of the trouble.
you should try to model in single surfaces as much as possible.. eg. try to model the sidewall out of a single srf.(loft profiles or networksrf) before using the fillet command; and watch out for an even distribution of CP in the corners of the curves you are using to generate the surface.

If you want/have to use your current geometry, force the meshes for that object (only) to have a small maximum edge length, as this will force the "glitch" to happen in a smaller area, thus be less visible....
it will render better, but it is only a way of hiding the problem, if you zoom closer it will reappear; but it is ok in this view:

*btw. you unit setup might be a bit off.. your object is 185 meters long, with precision of 0.01 only.. so no detail below 1cm.... might be too little...