David Legland

Hi Orestis,

You can check the function 'intersectPlaneMesh', that computes the 3D polygon resulting from the intersection of a polygonal mesh with a plane. The algorithm used is simple, so there can be numerical issues. Then you can compute the area with the function 'polygonArea3d'. By considering several planes, you should be able to do what you want.

There is no function in geom3d for reading STL files. So you should either write yout own, or find one.

regards,
David

Hi Niru C,
This contribution is devoted to the visualisation of 3D images. For your problem, I would suggest trying my other contributions geom3d (#24484) and geom2d (#7844), in particular functions intersectPlaneMesh, and polygonLength.

I was using this app on R2012b but recently upgraded to R2013a and now have difficulty running the Slicer app. I'm wondering if that's a result of the new version of Matlab or if I did not install it correctly. Any assistance on this issue would be much appreciated.
Thank you,
Colleen

With all respect for this valuable submission. I do have some slight critique. I downloaded geom3d to "quickly" check against my code for the determination of the spherical angle, as the function "sphericalAngle" promised. I only called sphericalAngle exactly as indicated in its help. I ended up wasting two hours of quality time ploughing through various fixes. [1] calls to functions whose names have been changed. Sorry , but I just stopped keeping track(some have already been mentioned in these comments) and [2] createPlane, was called from within sphericalAngle apparently with the wrong dimensions. [3] intersectLinePlane complained about matrix dimension mismatch on line 71. Honestly, I consider perseverance one of my strenghts, but I gave up at this point, as I can't say how much more time this really simple operation would/should cost me should I continue with geom3d. Sorry, but a smooth program flow is really important, especially in extensive code submissions such as this one.

Dear David

Could you let me know if your library can be used i order to slice a 3d stl file with arbitrary planes?

The aim is to calculate the area bounded by the stl file in each slice.

With best regards