Keyboard input in games (for GLUT)

Almost every game use keyboard as input. I have been searching for 2 days on this topic and found quite much about it. Keyboards have many disadvantages, but main problems I found are different layouts and second that if you are pressing 3 keys at time, it can lead to corruption (row-column error). If you don't know what I'm talking about, keyboard is made as grid and it checks which row and column has connected. But if you press E,D (row 1,2 column 3) and R (row 1, column 4), keyboard can show even F because it find it pressed(row 2, column 4 both pressed).

So I think we can't do anything about that second, but if anyone got idea how to solve it better then use keys that don't form L, I'd be glad :)

But my main problem are different keyboard layouts which is real pain. I'm slovak so Slovak layout of numbers look like this: +ľščťžýáíé and with shift 1234567890, we also got QWERTZ but you can use QWERTY. You all know how the English look like but just for sure: 1234567890 and shift !@#$%^&*()

Most of time I'm using english one because I got used to it when programming. Anyway there are different people using different layouts. When you are making game that depend on which key is pressed, for example good old WASD pattern, you can't use that on french one which is AZERTY layout. It would be strange. Same as using numbers for choosing gun in action game. As you can see slovak would have to press shift to get it work.

I'm also using OpeGL. There is problem when you are mapping which keys are pressed. For example widely used solution to make map of 256 bools for each charakter, is suffering from SHIFT. You press a, SHIFT and release a you got: a down, A up. So I thought about binding some keys together, as A and a, 1 and !, but then I realized I'll just change layout and everything is wrong.

So what is solution for that? I think there is someone out there that is in game industry or made some game and had to solve this. Only solution that co开发者_开发技巧mes on my mind is to force english layout for UI (and choosen layout for chat).

After next searching I found what I need but I need cross-platform one: virtual key codes

And next search revealed SDL key

Result: Don't ever start with GLUT if you go making games, use SFML or SDL

Thanks to everyone for helping me, there were more problems in this so idea of key binding/mapping, SDL and so on, each helped me alot.

If you're getting a "character" every time user presses something, then your keyboard routines aren't suitable for game input - only for text entry.

You need to use input routines that completely ignore keyboard layout switching and operate on some kind of raw keycodes (so when user presses shift+a, you'll know that shift is pressed and that "a" key is pressed, but you won't get "A" character). Also, routines should allow you to query if a key is pressed or not.

For windows that is DirectInput or XInput. For cross-platform this is libsdl and SDL_GetKeyState. And you'll need to provide keymapping options for the user. Glut probably isn't suitable for your task.

The common approach seems to be to ignore the problem. Worse-is-better in its early stage.

Unfortunately I'm using svorak keyboard layout so it really doesn't just work for me.

I've been approaching this same problem by binding into multiple keys on the keyboard. So that player jumps from both x and j -keys. It doesn't do so well in something that isn't shoot-jump -kind of game.

Nice stuff would be if you could just find row/col or some driver-near interface to your keyboard.

Some auto-keyboard configuration software would be neat though I've not yet seen anything like that. Maybe we should write one?

First up, separate keypresses from text entry. You shouldn't care what letter or number comes up when you press a key with shift as well - the operating system should handle that and generate an event you can use in the rare times you need the text. Usually, you should just look for the key press and any shift presses and act on those.

Second, load the bindings from keys to commands from a data file, rather than hardcoding it. Distribute default bindings for QWERTY and whatever default layout you have. If the data format is quite straightforward then people won't mind customising it to fit their keyboard and preferences. You can also add an in-game keybinding editor later.

This isn't really about OpenGL since by default that doesn't care about keypresses. Perhaps you are using an addon library or extension that handles keys for you - ensure that whatever you're using can give you individual key values and the state of shift/alt/ctrl independently, and that it also provides text input via an independent system.

Allow your users to define the keys to use for each action ...

or use the arrow keys .. that should be pretty universal :)

Turn the keyboard input into metadata, so you could allow users to configure at their will but also provide different keyboard shortcuts depending on the keyboard layout used in a config file .