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Ticket #1967 (new defect)

Opened 2013-07-23T16:07:14-05:00

Last modified 2013-08-07T13:23:50-05:00

Threshold overlay affects drawing subsequent overlays

Reported by: aivar Owned by: bdezonia
Priority: trivial Milestone: imagej2-b8-analysis
Component: Analysis Plugins Version: 2.0.0-beta-7
Severity: serious Keywords:
Cc: Blocked By: #1681
Blocking: #1678


Suppose you have a threshold overlay and you want to draw a rectangular overlay on top of it that is overlapping. You can only do this by clicking outside the threshold and dragging. If you click in the threshold presumably this is taken as selecting the threshold overlay rather than initiating a new overlay.

This is the normal behavior for overlays: if you want two overlapping rectangles the second must be initiated at a point outside the first. If you click on a point inside the first handles pop up, so it's clear what is happening. Threshold overlays show no handles so it's not clear what's going on. This is related to ticket 1681, and this issue will probably go away once that is fixed.

If you have to have a rectangle overlay and a threshold but all four corners of the rectangle are within the threshold you can create the rectangle first or else create it elsewhere and drag it into place.

Change History

comment:1 Changed 2013-07-23T16:21:09-05:00 by aivar

I wrote "threshold overlays show no handles" but in fact the usual blue rectangle does pop up enclosing the entire display. It was my user error not to notice them. I'm not sure what else would be appropriate.

comment:2 Changed 2013-08-07T13:23:50-05:00 by bdezonia

Aivar clarified something for me recently. After the threshold is present you can't draw overlays over the pixels in the threshold (rendered in a special color). However within the image where there are no thresholded pixels you can draw all you want. Again you can draw in an open area and then drag to where you want it.