I was hoping somebody would come up with a clever solution for this.
I think it would be interesting and potentially useful.
I can't think of a simple way to solve the geodesic problem, but yes,
given an object, you can use Measure to get length, or area, or
whatever (see the module help).
So worst case, you have to pick a set of points with ProbeList, then
Measure the length of all line segments (macro to accumulate total
length). Yuck!
Maybe something along the lines of projecting the surface to 2D,
drawing the geodesic on the 2D surface, Sample'ing it to generate a
lot of points along it, then reproject it by Map back to the 2.5D
surface, then Measure. I have not tried this idea, but it might work.
Or pick end points on the 2.5D surface, determine a plane
(MapToPlane) using these, make said plane more or less normal to the
2.5D surface (just pick a third point on the surface but not on the
line), then Measure the length of the mapped line on said plane. The
assumption is the plane only intersects along one line making all
other points on the plane invalid. You might have to cull all the
invalids to get an object that Measure can ingest.
Hello Opendx-users,
(Question):
Is it possible to use opendx to pick two points on a
non-linear (iso)-surface and measure the ìcompleteî
distance? In addition, would it be possible to depict
the measured distance with a different colored
iso-surface (ie an iso-line)?
An example of a non-linear iso-surface could be waves
from an ocean or hills on land. I want to be able to
pick two points on the surface and measure the
complete distance between the two points that is up
the wakes and down the troughs of the wave(s). Then
display the result.
(Solution needs help):
I know it is possible to use the pick module to pick
landmarks on an iso-surface. Now the next step would
probably to find the shortest path from the two
selected points on the iso-surface. (I do not recall
seeing that algorithm in opendx as a module or macro
but it may exist somewhere elseÖ) Once the path is
determined those (points or vertices) could be
measured to get the length and form the line???
I do not know enough about the internals of opendx. I
was hopping to see if this has been done before or
perhaps a different approach...
-jj
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