From: Walter Roberson <>
Newsgroups: comp.soft-sys.matlab
Subject: Re: find distance along complicated geometric surface
Date: Mon, 17 May 2010 16:16:31 -0500
Organization: Canada Eat The Cookie Foundation
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Walter Roberson wrote:
> Meagan wrote:
>> I am trying to find the distance between two points on a shape that is 
>> defined by vertices and faces. I can't just use the distance formula 
>> because I need to make sure that the entire distance between the two 
>> points is in contact with the shape surface. I have no idea how to 
>> start doing this or if this task is even possible so any input would 
>> be greatly appreciated.
> Sounds tricky.
> To cross-check

Another question to cross-check: is this a 2D or 3D problem (or more?)

When you speak of "distance" and needing contact with the shape surface, would 
I be correct in figuring that what you want is the "path length" ? Just to be 
sure we have disambiguited "distance" correctly.

For example, if we had a discretized helix, then the distance between two 
points would be the same no matter how tightly or loosely the helix was coiled 
(provided that the coils did not touch) ?