Editing annotations has issues in two-page "book" view

ProjectMirador / mirador-annotations

a Mirador 3 plugin that adds annotation creation tools to the user interface

https://mirador-annotations.netlify.app/

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Editing annotations has issues in two-page "book" view #24

Open robcast opened 4 years ago

robcast commented 4 years ago

When you create an annotation on the right page in two-page book view the annotation is placed on the left page canvas with SVG overlapping the right page.

Either we should fix handling annotations on two canvases simultaneously (may be difficult) or disable adding and editing annotations in two-page mode with a warning to switch to single-page mode.

lutzhelm commented 3 years ago

Additionally, the annotation is placed on every currently visible canvas.

A fix would require to check if there are multiple currently visible canvases, and if so, to calculate how the coordinates translate to the correct canvas, dependent on the current viewingDirection.

lutzhelm commented 3 years ago

Fixing this issue might indeed be difficult:

The actually annotated canvas has to be determined from the SVG or xywh coordinates
The coordinates have to be corrected in relation to the offset of the correct canvas
The editor allows creating annotations that include regions of two canvases. I have no idea how this could be handled. Create two SVG Selectors, splitting the original SCV along the canvas border?

For the moment, I suggest to avoid creating annotations in multi canvas views; see PR #43.

robcast commented 3 years ago

I haven't checked @lutzhelm 's PR but I think it is a good step in the right direction to put up a warning when the user tries to create or edit an annotation in two-page view.

Better yet would be a real fix that treats each page's annotations separately but in the mean time a warning would be nice :-)