Slice-plane tool in Geometry Mode

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Slice-plane tool in Geometry Mode

randress
As explained in another thread ( http://forum.featool.com/Integration-of-Current-Density-over-Slice-Intersection-tp180p182.html ) currently, a planar slice cannot be added during post processing such as might be used for integration:
Precise Simulation wrote
Boundary integration is only available on defined (external and internal) boundaries (not general cut planes). So in your case you would have to split the cylinders in half (or at the plane you want to perform the boundary integration). This should after meshing create internal boundaries that you now can select in the "Boundary Integration" dialog box (Switch to "Boundary" mode to see the boundary numbering, and toggle the "Interior Boundaries" check box in the lower left hand side of the "Boundary Settings" dialog box to see the numbering of internal boundaries).

The reason for this (limitation) is that boundary integration is for both practical and accuracy reasons performed on selections of grid cell faces (or edges in 2D). And the way to ensure the grid generation algorithm does indeed mesh a reasonably smooth plane/boundary is to first define it in the geometry.
In another thread ( http://forum.featool.com/Export-of-STEP-geometry-to-Gmsh-cut-with-plane-and-re-import-STEP-tp423p426.html ) a method is outlined whereby the equivalent functionality may be accomplished in the Geometry mode:
Precise Simulation wrote
If your desired cutplane is aligned with the x, y, or z axis you should already be able to do this with the existing capabilities, as for example:

1) Make an in-place copy of the object you want to split using the "Copy/Transform Object..." button or menu item.

2) Create two blocks that touch along the plane you want to split, but extend a bit beyond the object in the other 5 directions/planes.

3) Subtract one block from the orginal object, and the other from the copy.

4) You should now be left with two halves of the original object split along the plane where the two blocks touched.
Could this technique be implemented by a tool added to the Geometry Mode menu which would, for example, provide for the definition of a plane's perpendicular vector (x, y, z) and a contained point (x, y, z) which would then be used to bisect any/all selected objects? Perhaps a similar tool would be appropriate for the 2D and 1D modes.

Kind regards,
Randal
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Re: Slice-plane tool in Geometry Mode

Precise Simulation
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Thank you for the suggestion Randall. I am working on updating the geometry engine with support for more CAD tool functionality and will eventually get around to incorporating a proper slicing tool, but it might take some time for this to be implemented and made available.
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Re: Slice-plane tool in Geometry Mode

randress
Precise Simulation wrote
Thank you for the suggestion Randall. I am working on updating the geometry engine with support for more CAD tool functionality and will eventually get around to incorporating a proper slicing tool, but it might take some time for this to be implemented and made available.
Good to hear.

I must confess that what prompted me to suggest this was the trouble I was having with the dup&sub technique as reported here ( http://forum.featool.com/Adding-an-interior-boundary-by-duplication-and-subtraction-tp506.html )

Now that you have explained that my issue there was not my inability to properly create the boundary AND have provided a work around, this feature does not seem so urgent any more :-)

Kind regards,
Randal