It is possible to put an image on the sheet but drawing over it can be difficult as the image tends to be selected in preference to other drawing elements. (I've done this to annotate a PCB layout for test points)
A 'Background' layer with option to toggle between it and 'Foreground' would solve it but suggest symbols and wiring only allowed on 'Foreground'.
Perhaps the existing grid would be shown on the 'Background' or it could be used for a custom grid.
Phil
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It is possible to put an image on the sheet but drawing over it can be difficult as the image tends to be selected in preference to other drawing elements. (I've done this to annotate a PCB layout for test points)
A 'Background' layer with option to toggle between it and 'Foreground' would solve it but suggest symbols and wiring only allowed on 'Foreground'.
Perhaps the existing grid would be shown on the 'Background' or it could be used for a custom grid.
Phil