In the FAQ downloads, you will find a sample code of how to set NURBS surfaces. The knot vector KnotsX, KnotsY determines how the control points affect the NURBS curve. The number of knots is equal to the number of nodes plus the order.
Question
I am using the COM interface and Grasshopper for the calculation of complex structures. For this task, I need to create NURBS lines. Could you explain how to set NURBS? For example, what kind of data should be provided for knots?
Mr. Baumgärtel provides technical support for Dlubal Software customers.
![Scissor Lift](/en/webimage/013457/2847437/main.png?mw=512&hash=e35b0ba070a5f9f25a45fda767a74f3ef4ab5d05)
![Two Identical Models with Rib Type Members](/en/webimage/011713/2599289/01-en-jpg.jpg?mw=512&hash=b1d54ebe39accbd4d6f5393be39c8bddbdb0d0a2)
![Diagram of Components for Distance Calculation](/en/webimage/008716/2075003/01-de.png?mw=512&hash=9f2525444a7414dfb1c05a73e375e9c4fe4f47b1)
![Finding Start Nodes of Lines via COM Interface](/en/webimage/008815/786698/01-en.png?mw=512&hash=65e98cfe859ce35a3e3e9da47a0ef9335401520e)
![Feature 002423 | Displaying Results in Solids](/en/webimage/031923/3325382/FE_Solid_EN.jpg?mw=512&hash=d2950a5e2123942fab13aad296e814c67695c955)
The results of solid stresses can be displayed as colored 3D points in the finite elements.
![Improved Calculation Performance by Optimized Consideration of Nodal Degrees of Freedom in RFEM](/en/webimage/015531/2983511/Berechnungsperformance_EN_(1).png?mw=512&hash=ea9bf0ab53a4fb0da5c4ed81d32d53360ab2820c)
The number of degrees of freedom in a node is no longer a global calculation parameter in RFEM (6 degrees of freedom for each mesh node in 3D models, 7 degrees of freedom for the warping torsion analysis). Thus, each node is generally considered with a different number of degrees of freedom, which leads to a variable number of equations in the calculation.
This modification speeds up the calculation, especially for models where a significant reduction of the system could be achieved (for example, trusses and membrane structures).
![Extended Display of Surface Strains](/en/webimage/012851/2635393/N_386_02.png?mw=512&hash=8ca45b89302044b96809c681e2688d15a0f63fe4)
Display extended strains of members, surfaces, and solids (for example, the important principal strains, equivalent total strains, and so on) in the Project Navigator - Results in RFEM as well as in Table 4.0.
For example, you can display governing plastic strains when performing the plastic design of connections with surface elements.
![Export RFEM or RSTAB Models to *.glb or *.glTF Format](/en/webimage/010965/2466101/N_386_03.png?mw=512&hash=148c1c16f3620b9ca170dc77253f6c2830d84b73)
RFEM and RSTAB models can be saved as 3D glTF models (*.glb and *.glTF formats). View the models in 3D in detail with a 3D viewer from Google or Babylon. Take your VR glasses, such as Oculus, to "walk" through the structure.
You can integrate the 3D glTF models into your own websites using JavaScript according to the instructions (as on the Dlubal website Models to Download): "Easily display interactive 3D models on the web & in AR" .