[Vm-dev] [Windows cog vm] [Keyboard events related] about keycode mapping

[Guillermo Polito]

Hi!

On Thu, Jan 26, 2012 at 4:41 PM, Andreas Raab <andreas.raab at gmx.de> wrote:

>
>
>
> On 1/26/2012 15:43, Guillermo Polito wrote:
>
>
>
> The question is:
>
>  Should KeyDown, KeyUp and KeyChar events for the same key produce the
> same keyCode?  I think yes.  Because the keyCode indicates the key pressed
> in the keyboard. Doesn't it?
>
> It does. Which is precisely the reason why it *can't* produce different
> values when you press the shift key with it.
>
>
The KEY you are pressing does not change depending on the modifier; your OS
> decides that the combination of the Shift key and the P key produces an
> uppercase P character. Similarly to the OS deciding that (when using dead
> keys for example) pressing the accent key followed by the a key produces an
> accented a. Would you expect the keyDown value for the accented a to change
> as well? This way lies complete madness.
>

But you're talking about the keychar event and I've not modified at all
it's behavior :/.  And yes, I agree I should not do any conversion on KeyUp
and KeyDown :).


>
> Maybe you don't understand what these events are used for. Consider you
> are writing a game and you're using shift and control key for primary and
> secondary weapon action. Would you expect that the person writing the game
> needs to handle all of the various control and shift key combos in order to
> find out that the user pressed the a key to move forward?
>

Oh, yes I do understand.  Maybe I didn't explain me fine, sorry.

The main problem is that I want keycodes to be the same through the three
platforms (unix, mac and windows).  And for that, I have to do a mapping
somewhere (this piece of code I wrote today was to play and see how it
behaves, because the codes are to be defined :) ).

So, I thought those conversions could be done through the *keymap* array.
Maybe that's not the way to do the mapping, but *the* mapping should be
done somewhere.

Then, after looking at how other platforms work, I reached the conclusion
that if events for the same stroke have different keycodes I don't care :),
since the keycode should only be important for KeyUp and KeyDown and not
KeyChar (where I should only care about charCode).


>  Now, utf32Code should be only used on KeyChar events, and I don't care
> about them.
>
>  How does it work now?
>
>  (KeyDown, KeyUp) and KeyChar events send different keyCodes to the image.
>
>
> Which is exactly the right thing to do.
>

I answered before :).


>
> Cheers,
>   - Andreas
>

Thanks, I'm learning!
Guille
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