comp.lang.idl-pvwave archive: archive » Re: Creating an ordered 'blob' ROI from a messy 'criss-crossed' ROI....

Home » Public Forums » archive » Re: Creating an ordered 'blob' ROI from a messy 'criss-crossed' ROI....

Show: Today's Messages :: Show Polls :: Message Navigator
E-mail to friend

Re: Creating an ordered 'blob' ROI from a messy 'criss-crossed' ROI.... [message #75929]

Thu, 05 May 2011 20:49

David Fanning
Messages: 11724
Registered: August 2001

Senior Member

James Preiss writes:

> There is no general way to solve this problem unless you put some
> constraints on allowable region shapes. For example, see the image I
> just made at http://imgur.com/NqIxG . If you only allowed convex
> ROIs, then you could take the convex hull of the points, but I doubt
> you want that restriction. I can't think of any elegant solutions -
> you'd be better of demanding that your users click in order.

I agree with this, but there are times when you have too
many points bunched up, and too few points somewhere else.
I use the Coyote Library program ArcSample to "even" the
points out, so there is approximately an equally spaced
density of points around the exterior of the ROI.
Naturally, your mileage may vary with this solution, too.
But, I have used it successfully on more than several
occasions. :-)

Cheers,

David

--
David Fanning, Ph.D.
Fanning Software Consulting, Inc.
Coyote's Guide to IDL Programming: http://www.idlcoyote.com/
Sepore ma de ni thui. ("Perhaps thou speakest truth.")

Report message to a moderator

[Message index]

		Re: Creating an ordered 'blob' ROI from a messy 'criss-crossed' ROI.... By: David Fanning on Thu, 05 May 2011 20:49
		Re: Creating an ordered 'blob' ROI from a messy 'criss-crossed' ROI.... By: James Preiss on Thu, 05 May 2011 20:35
		Re: Creating an ordered 'blob' ROI from a messy 'criss-crossed' ROI.... By: George Millward on Thu, 12 May 2011 12:21

Previous Topic:	Coyote Down Under
Next Topic:	object programming question

-=] Back to Top [=-

[ Syndicate this forum (XML) ] [

] [

]

Current Time: Fri Oct 10 16:31:08 PDT 2025

Total time taken to generate the page: 0.08070 seconds