PowerNURBS

Discussion in 'Software' started by Troutcatcher, Jun 17, 2007.

  1. Martijn_vE
    Joined: Apr 2005
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    Location: Netherlands

    Martijn_vE Marine software developer

    The idea is that you can use less controlpoints and are not restricted to a topologically rectangular controlgrid. A row of controlpoints does not have to go all the way but may end on an arbitrary column (that's a T junction). So yes, T-Splines are certainly an improvement over the default NURBS surfaces. The are a mixture of subdivision surfaces and NURBS surfaces. The attached image shows an example of something you cannot produce with a single NURBS surface. Even with multiple surface this will be difficult to produce and you will have cross boundary continuity problems. The image also clearly shows the T-junctions.
     

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  2. Troutcatcher
    Joined: Dec 2005
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    Location: 66°N

    Troutcatcher Junior Member

    T-Splines to NURBS?

    Martijn,

    Do you know if when saving surfaces created using T-Splines as NURBS yields a complex mixture of trimmed NURBS patches or just a clean and beautiful surface containing no hidden elements?

    (For example the N-sided-Surfaces-to-NURBS conversion engine supplied with FreeDimension yields a horrible mixture of trimmed NURBS patches).....I was wondering if T-splines to NURBS conversion produced better results?
     
  3. Martijn_vE
    Joined: Apr 2005
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    Location: Netherlands

    Martijn_vE Marine software developer

    In almost any case the T-splines surface will be converted to multiple NURBS surfaces. But they are not trimmed surfaces. Just separated. If the algorithm is decent curvature across the boundaries of the patches will be continuous though.
     
  4. Troutcatcher
    Joined: Dec 2005
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    Troutcatcher Junior Member

    That´s good......because I hate trimmed NURBS:cool:
     

  5. yipster
    Joined: Oct 2002
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    yipster designer

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