Re: [hatari-devel] Enhanced keymap support

[Eero Tamminen <oak@xxxxxxxxxxxxxx>]

Hi,

On 5.11.2021 9.36, Thomas Huth wrote:
> schrieb Eero Tamminen <oak@xxxxxxxxxxxxxx>:
[...]
> > Problems:
> >
> > 1. Hatari symbolic key handling should have support for all keys in
> > the Atari ST layout, but it does not.  E.g. several of them do not
> > have SDL defines.
> >
> >     => key names could be used for mapping those
> >
> > 2. Hatari ignores everything using AltGr, although that's needed e.g.
> > for @, [] and {} keys on Finnish keyboard.
> >
> > 3. mapping some of the keycodes properly requires knowing the current
> > TOS keyboard layout (US, French etc) to inject correct ST scancode,
> > but Hatari currently hardcodes US layout.
> >
> >     => Could Hatari infer keyboard layout from TOS version,
> > multilanguage TOS header, and NVRAM?
>
> I think that just doesn't scale. Hatari could guess the right keys in
> the most common cases, but IIRC there are also Atari programs that
> change the layout during runtime...

I do not think Hatari needs to care what happens after emulation starts. 
 If user adds some
extra keyboard layout change to Atari side,
it's his/her responsibility then, not Hatari's.


> Honestly, I think we should get completely rid of the symbolic keyboard
> mapping nowadays (apart from the loadable keymappings). The symbolic
> key mapping was mainly included since you could not rely on the scancode
> layout with SDL1 (e.g. on macOS the layout was completely different
> there), but with SDL2, we now have the guarantee that the scancode
> layout it fixed (based on the USB standard, as you've mentioned it).

As I mentioned, there are some keys that cannot be
mapped directly, because the physical layouts of
PC and Atari keyboards differ a bit (mostly that
single key Vincent mentioned).

And there are also keyboards which do not look
like ST keyboards at all / have a lot less keys.

=> I think symbolic key mapping is still needed
for those, but it needs to be significantly
improved.


> We then should teach users to think of the Atari keyboard layout when
> typing keys (especially non-letters), and maybe provide some pictures
> of the Atari keyboard with the keys and corresponding scancodes in
> the manual.
>
> For people who want to type special characters in a way that rather
> matches their host keyboard, they then could use the key mapping
> functionality (which should still be based on symbolic host key names,
> of course, I don't mean to get rid of these - i.e. the loadable key
> mapping with symbolic host keys should be done on top of "hard-coded"
> scancode key mapping that is included in Hatari).
>
> Makes sense?

Do you mean removing the user option of
selecting how keys are mapped?

I'm fine switching the logic to this:

1. If no keymap loaded, check keypad (like before)

2. If keymap loaded and key matches, use that

3. Otherwise try scancode

4. If still no match, try symbolic



	- Eero