Box/Rectangle overlay on the image to have a better idea of mask size before creating the mask

[4rnaudB]

Checklist

• I've given this issue a self-descriptive, meaningful title (e.g. Implement optimization algorithms for shimming)
• I've described the new feature and its expected behaviour
• I've described the usage scenario for the new feature
• (optional) I've added some ideas about how to implement my suggestion
• I've given this issue the correct labels

Feature Description:

Add a button or use the size button to make a mask preview appears on the screen. You could then modify the mask size the same way you modify an image size on word for example. The current mask size could appear in the size text boxes.

Implementation Suggestion:

Add a function to the size button where it activates/deactivates the mask preview

Additional Context / Screenshots:

[jcohenadad]

@4rnaudB i'm not sure i understand this feature. There is already a "preview" button in the FSLeyes GUI to display/hide an image.

Maybe you could do a quick drawing (with screenshot from FSLeyes window) showing what you have in mind? Sometimes a picture is worth a thousand words

[jcohenadad]

Also, in general, I would try to minimize the production of code that duplicates with FSLeyes' existing features. Eg, FSLeyes already has an extensive masking toolkit:

Instead, I would suggest to add documentation that explains how users can leverage these features.

[4rnaudB]

I'm not fully familiar with shimming-toolbox yet so there might be the feature somewhere already, but I was thinking in this image:

I would like to be able to modify manually the mask size by dragging the white rectangle just like you change a picture size in word. The current mask size could be displayed in the size texte boxes to have a better idea of the size of the mask you want.

[jcohenadad]

I'd like us to re-think the whole masking GUI, see #49