WISH: dynamic tessellation


in rhino there is allways the difference between the perfectly smooth nurbs surface and corser rendermesh . This leads to many confusions. (“why is my geometry so jagged?” etc.)

Setting the rendermesh to a very fine resolution on default doesn’t solve the problem as it would slow down rhino on weaker hardware.

The best thing, in my opinion, would be to tesselate the rendermesh dynamically based on the view distance. This would allow for fine mesh when it’s needed upclose and would eliminate the current spilt between the nurbs-defined smooth surface and what the user sees in the viewport - as he or she can allways zoom in and get a finer representation of the surface.

For slower hardware the quality setting could adjust the viewdistance/meshsettings quotient to ensure a good performance.

Just my two cents – :wink:


Are you getting jagged meshes for your Rhino models?

We won’t be performing tessellation on the GPU any time soon. Driver support for these techniques has not been the best and it is an absolutely massive project that would still not fit with all of the ways Rhino needs to provide different architectures mesh information There are other optimization techniques that we can add to Rhino that will improve display performance

I see, thanks.

Are you getting jagged meshes for your Rhino models?

no, not really. But every other day there is a person on the forum having a question about the apperent “broken” model of his/hers. 99% of the time it’s just the rendermesh showing through.

I think McNeel could do a little better to explain the difference between the underling math/nurbs surface and the render mesh. This applies to rendering, 3D printing, milling etc. (rhinocam for example just mills the rendermesh not the actual nurbs surface)

A lot of people don’t know about the difference hence all the questions or from experience badly milled surfaces.

I thought gpu tessellation can be activated in rhino 6 in the openGL settings or applies this only for curves?

This only applies for curves (including edges and isocurves). The reason we even have a checkbox for this in the OpenGL setting is that we have found this feature fails miserably on some drivers that report that they support the feature.

Another trick is to search the forum before asking the question! :wink:

But I know, I know, I have failed on this one too - asked before searching the forum, and worse, before reading the Help file.

I think that by now the answer has slipped out of the lab, and while writing a question on this subject, the forum itself suggests related previously answered questions.

If that isn’t enough, where to put the “answer” if noone (or very few) are looking actively searching for the subject/question anyway? :slight_smile:

// Rolf