Implement a multi-view of the image with a high and 1:1 zoom to facilitate image editing
When I do extensive image editing with clone/heal I have to work on a high zoom to be accurate with the paint tool, but I need at the same time to check the result with a normal zoom. Thus, I would like to split the view in two, with one side showing the image with a high zoom (working) and the other with a normal zoom (control).
( For implementation details, maybe I missed something, but GPU API like OpenGL handle perfectly the display of image at a zoom >= 1 (exact pixelisation), and we should be able to get a good result for zoom < 1 (interpolation). )