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I need to find the vertices of an ROI shape created in IDL's XROI, so that I can redraw the ROI on multiple images. I know you can find the centroid, area and perimeter with the GEOMETRY command, but I can't find anything about vertices.

Is there a way of finding the coordinates of an ROI's vertices in IDL?

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up vote 1 down vote accepted

Just landed on this query. Hope you have found the answer by now, or if not, here I guess is the answer.

For a given roi object, say 'oroi', use this command to get the vertices

>> oroi -> GetProperty, data=a

so, here 'a' will have the X,Y,Z values of the vertices. Actually do 'a(*)+=0.5' to get the vertices values (at the center of the pixels).


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