obtain Nurbs from point clouds?
Hello,
I need to obtain nurbs surface from point clouds. or here there is a file called scattered point cloud it obtain urfaces, but i need export this surfaces as a CAD data, i need to convert it to igs format, for igs format i need obtain nurbs surfaces from point clouds, or is i possible to get igs format without obtaining nurbs from point clouds ? is it possible to covert matlab figure to igs format ?
Popularity: 2% [?]
iso2mesh: a 3D surface and volumetric mesh generator for matlab/octave
Filed under: Biotecnology, CAD, Computational Geometry, Graphics, Medicine
- iso2mesh is a matlab/octave-based meshing toolbox. It can create 3D tetrahedral finite element (FE) mesh from iso-surfaces and 3D binary volumetric images such as segmented MRI/CT scans.
- iso2mesh is an open-source software developed by [Qianqian Fang] at the [Photon Migration Lab], [Martinos Center for Biomedical Imaging], [Massachusetts General Hospital (Harvard Medical School)].
- A sibling project, metch – a mesh registration toolbox, is also hosted with this website.
Learn Qianqian’s other projects
- [Ask a question], check reply
- Publications involving iso2mesh
- [Verdict on iso2mesh]
- Frequently Asked Questions
Learn more on: http://iso2mesh.sourceforge.net/cgi-bin/index.cgi
Popularity: 4% [?]
Fast Surface Reconstruction: Delaunay2.5D
Filed under: Algorithms, Computational Geometry, Graphics
Can a surface reconstructor be faster than a 2D mesher?
It is coming soon the Delaunay2.5D algorithm a new fast surface reconstructor. It is currently in a prototype state, still have to code pre-processor and post-processor parts. I will include it in my thesis.
This algorithm can deal with millions of points in a matter of a few second, it is basically faster than a 2d delaunay triangulation. For this reason I am also thinking about extend it to 2D and 3D triangulations.
More infos about the algorithm performances and how does it work will be given in future. At the time I only have this video demostration and a demo version.I was impatient to publish something about it 
.
Delaunay2_5D has been released here.
Popularity: 28% [?]
Surface Reconstruction From Scattered Points Cloud: MyCrustOpen
This part, differently from the first one, supports any kind of open surfaces. It can substitute tools like griddata in cases where points are completly scattered. If they aren’t in z=f(x,y) form griddata doesn’t work, a surface recostructor is needed.
Here is a brief description:
This version has been developed for open surface.
Differently from crust based algorithm does not ensure a tight triangluation and sometimes self-intersecant triangles are generated, it is also generally slower. The final surface may need some repair work which this utility does not offer.
But there are two great advantages, it can be applied on any kind of open surface for which the Crust fails, it supports not regular surface like the Moebius ribbon, and most of all, surface can have any kind of holes, open feature shouldn’t create problem.
You can see the screenshot or demo models for examples.
Here is a simple example:
load Nefertiti.mat%load input points from mat file [t]=MyCrustOpen(p); figure(1) hold on title('Output Triangulation','fontsize',14) axis equal trisurf(t,p(:,1),p(:,2),p(:,3),'facecolor','c','edgecolor','b')
Input:
p is a Nx3 array containing the 3D set of points
Output:
t are points id contained in triangles nx3 array .
If any problems occurs in execution, or if you found a bug, have a suggestion or question just contact me at:
reports about models on which the algorithm fails are greatly aprecciated.
This work is free thanks to users gratitude, if you find it useful consider buying me a beer. Thank you.
Popularity: 33% [?]
Surface Reconstruction from Scattered Points Cloud: MyCrust Robust
It is now available on Matlab file exchange the robust and new version of MyCrust.
I hope you’ll enjoy it !
MyCrust take as input a 3D scatter points cloud and return a tight, manifold, triangulation.
Remember that crust algorithm needs a cloud representing a volume, so open surface may give inaccurate results. For example : a plane can not be triangulated, half-sphere is in doubt, a sphere with a small hole shoud be good.
The more points are given the best the surface will be fitted, of course in this case you would have to wait more and in the worst case a memory help error may occurs. The best results are obtained with more points in high curvature feature.
The old version did not ensure the output surface to be a manifold so it could be used only for graphical purpose. In the new one a tight, regular manifold is returned. It as outward normals orientation, after using this algorithm is very easy to get an STL file from a point cloud.
I added a manifold extraction tool that also correct the errors (slivers) generated by delaunayn during the initial tessellation.
Popularity: 49% [?]
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