A huge image is shown on screen; you can pan/zoom the image to see all the detail or the entire image at once.
Each of the possible operations can be performed by one of several mouse actions. Some operations have only one type of mouse activity.
When the operation can be performed using the keyboard, then the key bindings are listed as well.
Click and drag the image (background), release during drag, i.e. act it out as a swipe movement.
Either swipe (see above) or drag the image (background) and hold in place, then release, to pan the image around.
You may also move the mouse near the ‘edges’ to auto-pan.
keys: [Page Up], [Page Down], [Arrow Up], [Arrow Down]
Click somewhere to center on that pixel.
keys: [+], [-], [Keypad +], [Keypad -]
keys: [END], [E]
Create and test mobile/tablet actions for each of the operations.