Feature suggestion - Resolution dependent scaling factor (simplified but similar to CRT Multi-Sync displays) #4922

DosBox Staging has a very good global viewport scaling setting yet I consider that could be further improved by adding resolution-dependent scaling factors.

Very good CRT Multi-Sync displays allowed for multiple profiles to be saved which, in effect, provided various resolutions and refresh rates with a particular scaling and "viewport" position (the active display area). It may not be necessary to provide the full range of settings (positioning including), but a scale factor at least on both the x and y axis would be very helpful (ideally, x and y stretch values may be different, which could provide some interesting results). It may help if the scale factor could override, if needed, the ideal integer scaling computed by DosBox Staging, as an interim measure, allowing resolutions such as 800x600 to fill a 2560x1600 screen, as well as cover other fringe situations (such as not needlessly scaling a 320x200 one to be unrealistically big).

Ideally, I would see the implementation of the resolution-dependent scaling factor as a single variable holding a string of values for specific resolutions (I am aware that there is a very long array that could be defined, with all the potential VESA and non-VESA ones available or just a reduced set). This may require more thought than the simplified perspective I provided, to be both elegant and in tune with DosBox Staging approaches. I hope this suggestion is useful. Thank you!