Comment by Denvercoder9

Comment by Denvercoder9 3 days ago

Your computer doesn't actually know what the keys for WASD are. It just receives a number (commonly called scan code) for the pressed key from the keyboard, and has to use the mapping to determine which key that actually was.

There's some convention for which scan code to use for which physical position on a keyboard, but that's not correlated with what's actually printed on the key caps. E.g. on common QWERTY keyboards the "A" key will have scan code 4, but on AZERTY keyboards it will have scan code 20.

Games can probably get away by listening for the scan codes of the keys in the position commonly used by WASD, but it's a bit fragile, and they can't actually tell you what's printed on the keys they're listening to. The lack of consistenency is certainly annoying, though...

snuxoll 3 days ago

> Games can probably get away by listening for the scan codes of the keys in the position commonly used by WASD, but it's a bit fragile, and they can't actually tell you what's printed on the keys they're listening to. The lack of consistenency is certainly annoying, though...

The operating system knows how to map scan codes to characters based on the keyboard mapping the user has selected.

    Win32: MapVirtualKeyExA / MapVirtualKeyW
    MacOS: CGEventKeyboardGetUnicodeString / UCKeyTranslate
    Linux: xkb_state_key_get_utf8

Hell, glfw nicely wraps all of these up with glfwGetKeyName.

Stop reading character codes directly, use the scan code and when displaying them map it using the system API so people see the right freaking binding. It's not rocket science,

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zamadatix 3 days ago

Scancode vs character code is what they are describing:

Games SHOULD use scancodes for positional mappings (like WASD) and rely on the system keymap to decide what letter to display them as. There is no "probably" here, the scancode is the scancode and the keymap is the keymap.

Games OFTEN use the character codes directly regardless if it's for a positional mapping or not. This requires explicit support in the game for each possible system keymap, otherwise you end up with nonsense mappings.

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