[Rhino]T-splines for Rhino 4

[jbshorty]

Has anybody tried this R4 plug-in yet? It uses the modeling techniques of subdivision, but works on n-sided spline surfaces . It can also convert a subd polygonal cage into t-splines, and then convert t-splines to nurbs patches... It's currently in beta stage, and it only runs within Rhino 4 Beta (no version for R3). I'm going to check it out this week if i have time. I was just curious if anybody else had some experience with it yet...

http://www.tsplines.com/

[jbshorty]

I had a chance to convert a Hexagon model into a TSpline polysurface model in R4. The whole process took 15-20 seconds with a single mouse click (see the picture for results). Once converted to TSplines, most of Rhino's Nurbs modeling toolset can be used to model it further. and also the Tspline polysurface can be edited much like a subdivision surface (using face extrusions, point editing, tesselating, etc)... It seems the TSpline modeling toolset is very early beta, so it is limited as a full modeler (this is my conclusion after reading the documentation for the Maya TSpline plug-in). But once the full toolset is built, TSplines will become a powerful method to model organic objects in Rhino. The fusion of Nurbs' precision with Subdivision's freedoms. I'm very excited about it...

[jbshorty]

one more example of TSpline conversion. This time i converted from the unsmoothed poly mesh. the result is much less control points than previous example. And notice the new TSpline polysurface became smoothed, so it looks just like my original subd turtle ...

[Jerzy]

Thats absolutely amazing and even if I could not test it yet as far I can see
it seems like dreams comes true for those of us who would like to see
subd applied to nurbs and its full editability is simply incredible !!!

I was looking for last two years some decent subd modeler because
I was unable to do these thinkgs in rhino. But now it seems the research is over. Wow !

jbshorty

could you post more examples with poligonal models in lo res and witout
subdivision applied to it. I want to see how this tspline plug handle this.

[jbshorty]

Here is another conversion i just did. the lo res mesh is all quad. But there is an obvious problem wherever the edges form poles. You can see it very noticably on his belly, and there are a few poles on the top of his head, and also one between the legs where his "unmentionables" should be (if only i were so generous when i made him ). I am sure this could be eliminated if i rework the mesh so all the poles are in the hidden areas. Or after the fact i could remove the bad area, and use a nurbs patch or network surface to repair it... If you have a particular mesh you would like to use as an example, post it. i'll convert it to 3DM and post the file so you can inspect the results for yourself...

[marcello]

that's effectively amazing!!! would you post a more step by step explanation of the process in rhino 4?... I just know, and use, smurf, to "translate" meshes in nurbs, but your results are very very interesting!!!!

[jbshorty]

Hi Marcello, I will try to explain the highly complicated process:

1. import base mesh to Rhino
2. LMB the icon for "Convert to TSplines"

I wish i could tell you more, but it's that easy...

[Nate Owens]

JB.....

Hope to get a shot at testing this soon.

If your Hex model has brush displacement, is that preserved in Rhino if you modify the geometry?

It occurs to me that this may be a workaround for the texture mapping problems in Hex... they seem pretty straightforward in Rhino.

Thanks for the heds up on this tool....

[jbshorty]

Hi Nate. From what i've been told, the Maya plug-in can use the texture mapping tools and can also render with displacement. But right now, the Rhino version is early beta, so those features are not available. Not sure if they will become available for a while. Read this thread, with some comments by one of the developers:

http://www.tsplines.com/forum/viewto...3909af39b77a5b

I think the only way to convert your displaced Hex model into nurbs is to convert it from the high-res mesh. Not sure what the limitations are for TSpline conversion. I just converted a mesh of approx 80,000 polys, which took about one minute to process. Then i tried to convert a 1,000,000 poly mesh sphere and totally crashed ...

[marcello]

thank you , jbshorty... but, I can't see the "converttosplines" command; if I understand well, you import a mesh, then an automatic function translate it into a nurbs object... I use rhino 4 last update, and can't find,even when beginning to type "convertto...;"!... I sure miss something!

[jbshorty]

Hi Marcello. Did you download the plug-in from T-Spline's website? The first time you open R4 after installing, the T-Splines toolbar will be open. You have to run it from the toolbar, it doesn't run from the command line...

[chrisd]

jbshorty,

Do you know how the file size compares between the mesh, T-Spline and nurbs?

I assume T-Spline and Nurbs will be smaller, but how much smaller?

Chris

[jbshorty]

Originally Posted by chrisd

jbshorty,

Do you know how the file size compares between the mesh, T-Spline and nurbs?

I assume T-Spline and Nurbs will be smaller, but how much smaller?

Chris

there's no easy way to answer this. But, I would expect that a mesh would give you a smaller file size than either Tsplines or Nurbs. Here are the respective 3DM file sizes for the turtle model:

low res mesh = 204 Kb
hi res mesh = 976 Kb
tspline (saved normally) = 11.3 Mb
tspline (saved small) = 1.97 Mb
tspline (saved as geometry only) = 1.68 Mb

jonah

[chrisd]

Originally Posted by jbshorty

low res mesh = 204 Kb
hi res mesh = 976 Kb
tspline (saved normally) = 11.3 Mb
tspline (saved small) = 1.97 Mb
tspline (saved as geometry only) = 1.68 Mb

Hmmm, this is exactly the opposite of what I would expect, since T-Splines allows more patches in areas of greater detail. I had visions of T-Splines taking a 100Mb mesh file and getting it down to 50Mb or less, while at the same time being resolution independent.

I had hoped to have Rhino to play with T-Splines beta, but I have not been able to purchase Rhino yet. Now I'm not so sure T-Splines will do everything I wanted, although in many areas it still sounds like the ideal surfacing tool.

[jbshorty]

Originally Posted by chrisd

Hmmm, this is exactly the opposite of what I would expect, since T-Splines allows more patches in areas of greater detail. I had visions of T-Splines taking a 100Mb mesh file and getting it down to 50Mb or less, while at the same time being resolution independent.

I had hoped to have Rhino to play with T-Splines beta, but I have not been able to purchase Rhino yet. Now I'm not so sure T-Splines will do everything I wanted, although in many areas it still sounds like the ideal surfacing tool.

even if Tsplines created a smaller 3DM file, what is the purpose of that?

[chrisd]

smaller file size = faster editing, faster display etc.

[jbshorty]

Originally Posted by chrisd

smaller file size = faster editing, faster display etc.

Gotcha. but I was confused by this statement that you made: "I had visions of T-Splines taking a 100Mb mesh file and getting it down to 50Mb or less, while at the same time being resolution independent..." It sounded like you wanted to input a 100mb mesh object, and export a topologically independent mesh at lower resolution than original...

[chrisd]

Originally Posted by jbshorty

It sounded like you wanted to input a 100mb mesh object, and export a topologically independent mesh at lower resolution than original...

Now that would be ideal !!!

I had hoped that localized "subdivision" in T-Splines would save a lot on the size since the whole model need not be "subdivided" to the resolution of the smallest features.

Does the original mesh becomes a control mesh for the T-Spline?

[jbshorty]

Originally Posted by chrisd

Now that would be ideal !!!

I had hoped that localized "subdivision" in T-Splines would save a lot on the size since the whole model need not be "subdivided" to the resolution of the smallest features.

Does the original mesh becomes a control mesh for the T-Spline?

that would be great if it worked like that. But the original mesh is deleted during the conversion...

[jbshorty]

Originally Posted by chrisd

Does the original mesh becomes a control mesh for the T-Spline?

Hi Chris. I previously answered this question a little bit incorrectly, so allow me to update what little bit i have learned since then... The original mesh is deleted, which is fine because the TSpline object now has it's own control point cage that exactly matches the vertex locations of the original mesh cage. The Tspline surface is directly editable by moving points, or by extruding faces. At this time, there is no direct maniuplation of the individual faces, edges, vertices as you would have for a subd modeler. But the developers have stated that one of their goals is to have a box modeling workflow, so i am sure those features will be added soon.

jonah