Adding DOSBox as core for DOS TASing

[SergioMartin86]

• Add floppy disk mounting
• Add CD-ROM mounting
• Add disk swapping
• Add mem-based R/W Hard Disk
• Add multiple pre-formatted disk images
• Save Hard Disk to SaveRAM
• Load Hard Disk from SaveRAM
• Remove SDL dependency
• Add video buffer getting
• Add sound
• Add keyboard
• Add mouse
• Add joystick
• Create machine presets
• Add setting overriding
• Add file type association
• Add input mnemonics
• Add drive access light callbacks
• Add mem domains
• Add basic sound management settings
• Add basic video management settings
• Add basic cpu management settings
• Add check for saveRAM (if hd size is different, do not load it)

Lag frame detection cannot be implemented since these machines are IRQ, not polling based

Pending Fixes:

• CDRom images should be able to be passed as plain files (iso, cue+bin, etc), not as DiscAsset. -> Implemented a pseudo-fix: forcing cdrom images passed to DOSBox to be renamed to extension e.g., '.dosbox-iso', instead of .iso. Is there a better fix?
• Timing seems to be a bit off (too fast)
• Audio seems to be clicking (is this related to timing)
• Figure out why windows 3.1 doesn't detect the mouse: requires a special driver. Otherwise it works correctly.

Test Tools:

Used this to test joystick and mouse support:
https://www.vogons.org/viewtopic.php?p=187168#p187168

Check if completed:

• I have run any relevant test suites
• I, the committer, have read the licensing terms for contributors (last updated 2024-06-22) and am compliant

[YoshiRulz]

Opened #4242.

[vadosnaprimer]

VirtualWidth represents how the framebuffer should be stretched by frontend to look authentic to how the user saw the final thing back in the day. For IBM PC that means it's just a 4:3 monitor. Now since height can't be stretched (because it represents scanlines), we should just tell frontend to resize width to be 4/3 of height.

[SergioMartin86]

Thanks, I made the corresponding change and it looks correct now

[vadosnaprimer]

Currently loading .dosbox-iso (the only thing I tried) opens this dialog

[vadosnaprimer]

Mouse movement is now recognized! But is there a way to send deltas directly to the core without working with absolute values? Ideally relative mouse input would be exposed to user in addition to absolute position, so they could pick which of them to use for their particular game. In Doom core mouse movement ended up being relative-only, I think it would work for this core too as an option. This is valuable because absolute movement is very limited, like we saw with Doom, but relative movement allows unlimited turning, which is required for comfortable play.

[SergioMartin86]

Mouse movement is now recognized! But is there a way to send deltas directly to the core without working with absolute values? Ideally relative mouse input would be exposed to user in addition to absolute position, so they could pick which of them to use for their particular game. In Doom core mouse movement ended up being relative-only, I think it would work for this core too as an option. This is valuable because absolute movement is very limited, like we saw with Doom, but relative movement allows unlimited turning, which is required for comfortable play.

Yes, we can pass deltas, but we also need the absolutes for games that use it (Simcity) since it preserves the exact same position of the pointer as in the host window.

[vadosnaprimer]

That's what I mean by it being optional: just expose both mouse controls for users to decide which to use.