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Possible to select and area of an uploaded image?
What I'd like to be able to do would be to upload an image (like a floorplan) and save that image. When the user returns to that page, they see the image and they are able to then select sections of the image, like a room. It could be as simple as just click and drag an area, or click and drag lines that connect to make an area. I would then need to save this highlighted area so that they could come back later and see that area.
Then they could drag and drop components (like a light buib) onto that select area to associate the bulb to that room.
There are no Vaadin components that do image handling in the way you describe. There are a number of add-ons in the add-ons directory https://vaadin.com/directory that provide various image management features. However, I don't think that any one of them do exactly what you describe. You probably need to develop some client-side widget for this (see the Vaadin book chapters 13-15)
I wonder if it would be possible to use the html5 canvas addon with polyclip.js or something similar to that....
Combined with JSNI in GWT, see http://www.gwtproject.org/doc/latest/DevGuideCodingBasicsJSNI.html, it would be possible to extend the canvas add-on to use the polyclip.js library to manipulate images.