Re: [jts-dev] Remove line from within another line

[Martin Davis <mtnclimb@xxxxxxxxx>]

Ok, understood now.  Can you just remove the first and last points from the output line?  

Although I can see there will be (possibly common) situations where it's not that easy to determine this.  What might have to be done is to remove the endpoints only if they are identical to an endpoint of the subtracted line.

Not too hard to code this up, I think.  It's the first time I've come across this requirement - which makes me think it perhaps won't become a core function in JTS.  

What is the real world use case?

On Wed, Oct 10, 2018 at 2:50 PM Simon (SPDBA) Greener <simon@xxxxxxxxxxxx> wrote:

Martin,

Forgot image.

I don't see what other result would be expected?

There are situations where I don't want the end points of the line to appear in the output.

Difference removes the interiors of the line but not its boundaries. 

Now I expect that this is the "correct" result from the point of view of the standard, but that is not what I want.

The yellow line in the attached image is what I am after.

Regards

Simon

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