distance from point to surface with sign

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Permalink Reply by Daniel González Abalde on January 16, 2017 at 11:39am

Being 'N' as the normal at 'cPt' on surface and 'V' the vector from cPt to Pt, if the dot product of N and V is positive, then Pt is above, if not is below the surface.

If N·V>0 then Distance * 1 else Distance * -1

Permalink Reply by riccardo foschi on January 16, 2017 at 11:56am

thanks! it would be useful to have a toggle to make all this calculation at once in the "surface closest point" node

Permalink Reply by Joseph Oster on January 16, 2017 at 12:02pm

Make and post a GH model!  ALWAYS.

Measure the angle between the normal vector and the 'Vec2Pt'.  If it's at (or near) zero, the sign is positive.  If it's at (or near) Pi, the sign is negative.

P.S.  What Daniel said works too; I don't remember what 'Dot Product' means, but it works.

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