Currently, ROI are displayed in Signal/Image Views but in read-only mode: one can only modify ROIs using the "ROI editor" (menu entry: "Computing" > "Edit Regions of Interest...").

That is safe (it avoids accidental modification or removal of ROI) but it's not intuitive nor practical.

The idea here is to be able to manage ROI directly from the Signal/Image Views by adding a new button in the View's left vertical toolbar:

• This button would show a menu with actions related to ROI
• Actions:
  • Add a rectangular ROI
  • Add a circular ROI
  • Menu separator
  • Remove a ROI (enabled only if there is at least one ROI: it opens a submenu showing the list of ROIs - clicking one of them will remove it from the view)
  • Remove all ROIs

Adding a ROI:

• This would change the mouse cursor on the view (showing a "+" cursor)
• When clicking (and holding) mouse button, the user would draw the ROI directly in the View
• Then, after releasing mouse button, a confirmation dialog would show ROI coordinates: cancelling this dialog would cancel the operation

Moreover, this Issue also aims at allowing the user to modify the ROI directly from the Signal/Image View:

• ROI objects would no longer be read-only: the user would be able to move/resize them
• Releasing the mouse button after move/resize would automatically open the ROI confirmation dialog (with ROI coordinates that can be modified): cancelling this dialog would cancel the operation