- add zoom field, which is the same across different screen/window sizes
- scale is not the base state now, it is derived from the current zoom and the current screen/window size. it now represents the end scale of the image
- drag amount is still independent of scale/zoom (if we drag by 5 pixels, the image moves by 5 pixels)
- offset is still limited by the area and the current scale
* ImageViewer - limit zoom by the window/screen size
- add zoom field, which is the same across different screen/window sizes
- scale is not the base state now, it is derived from the current zoom and the current screen/window size. it now represents the end scale of the image
- drag amount is still independent of scale/zoom (if we drag by 5 pixels, the image moves by 5 pixels)
- offset is still limited by the area and the current scale