"No rois found on the map" when redrawing a second/new ROI polygon

[fmemuir]

For: openjournals/joss-reviews#6683

When an ROI is generated that doesn't have any transects available, generating subsequent ROIs causes a pop-up to appear saying "No rois found on the map".

To recreate error

1. Draw an ROI around a place with no transects
2. Select bounding boxes of choice within ROI
3. Click 'Load Transects'
4. Close error pop-up and locate to a different place with known transects (e.g. Santa Cruz)
5. Draw new ROI
6. Click 'Generate ROI'

To solve this, the cell must be re-run to create a new dashboard. Is there a button or command to clear the cache of failed attempts to find an ROI with transects, rather than having to reload a new dashboard?

[2320sharon]

Hi @fmemuir

Thank you for reviewing CoastSeg and for laying out the steps to replicate your issue. I was able to replicate the issue you encountered successfully.

The Solutions

There are 2 ways to fix this issue:

1. You can select 'shoreline' from the dropdown under 'Remove Feature From Map' and remove the shoreline at the old location from the map. You'll also need to remove the rois as well, use the same dropdown, click 'ROIs' and remove the ROIs.
   

2. You can use the remove all button to remove all the features on the map then re-draw the bounding box & generate the ROIs again.

After removing the old features the new ROIs should generate just fine.

Why it happened

To explain why this issue happened let me first explain what happens when the 'generate ROI' button is clicked. First, CoastSeg loads a shoreline within the bounding box drawn by the user and attempts to generate ROIs along the shoreline. If no shoreline is found in the bounding box or within any existing ROIs on the map, then the error message appears saying "No rois found on the map" because ROIs have to generated along a shoreline. What's happening in this case is the shoreline still exists at the first location where no transects were available. Since this shoreline is not within the bounding box where ROIs are supposed to be formed the error message appears.

I'll work on patching out this issue so no else encounters this problem in the future. In the meantime the two solutions I outlined above will work.

[fmemuir]

Thanks for the response and solution for this, I'd missed the 'Remove Feature From Map' buttons!