Convert keyboard::key into char

[snemed]

Hello,
I am currently realising a little game with SFML.
I try to implements settings in my game. So I try to let the player choose his Keys.
My ploblem is that I have got a "vector<Keyboard::Key>" and I want to display these keys on the screen. I try a "static cast" into "char" but it give to me the wrong key.

I use SFML 2.1. If someone have an idea to help me, thank you!

[Nexus]

You could use my library Thor and its conversion functions (see here):

sf::Keyboard::Key key = ...;
std::string keyName = thor::toString(key);

[snemed]

thank you for your answer. But I can't install your library Thor because the game have to compile on my professor's computer, who only has Basic libraries like SFML.

Do you know another trick?

[dabbertorres]

You could write your own conversion. You may be interested in how Nexus did it.

[snemed]

thank you for your answer.
It will be long but this is my only way.
if it works, i will post this function here.

[Nexus]

If you only need to convert from keys to strings and not vice versa, the simplest solution would be a big switch statement. You can look at the macro trick I used to avoid duplicating the identifiers.

[snemed]

Finally I done it.
this function can maybe be useful for someone.

string fromKtoS(const sf::Keyboard::Key& k){
        string ret;
        switch(k){

    case sf::Keyboard::A :

        ret="A";
        break;
    case sf::Keyboard::B :

        ret="B";
        break;
    case sf::Keyboard::C :

        ret="C";
        break;
    case sf::Keyboard::D :

        ret="D";
        break;
    case sf::Keyboard::E :

        ret="E";
        break;
    case sf::Keyboard::F :

        ret="F";
        break;
    case sf::Keyboard::G :

        ret="G";
        break;
    case sf::Keyboard::H :

        ret="H";
        break;
    case sf::Keyboard::I :

        ret="I";
        break;
    case sf::Keyboard::J :

        ret="J";
        break;
    case sf::Keyboard::K :

        ret="K";
        break;
    case sf::Keyboard::L :

        ret="L";
        break;
    case sf::Keyboard::M :

        ret="M";
        break;
    case sf::Keyboard::N :

        ret="N";
        break;
    case sf::Keyboard::O :

        ret="O";
        break;
    case sf::Keyboard::P :

        ret="P";
        break;
    case sf::Keyboard::Q :

        ret="Q";
        break;
    case sf::Keyboard::R :

        ret="R";
        break;
    case sf::Keyboard::S :

        ret="S";
        break;
    case sf::Keyboard::T :

        ret="T";
        break;
    case sf::Keyboard::U :

        ret="U";
        break;
    case sf::Keyboard::V :

        ret="V";
        break;
    case sf::Keyboard::W :

        ret="W";
        break;
    case sf::Keyboard::X :

        ret="X";
        break;
    case sf::Keyboard::Y :

        ret="Y";
        break;
    case sf::Keyboard::Z :

        ret="Z";
        break;
    case sf::Keyboard::Num0 :

        ret="Num0";
        break;
    case sf::Keyboard::Num1 :

        ret="Num1";
        break;
    case sf::Keyboard::Num2 :

        ret="Num2";
        break;
    case sf::Keyboard::Num3 :

        ret="Num3";
        break;
    case sf::Keyboard::Num4 :

        ret="Num4";
        break;
    case sf::Keyboard::Num5 :

        ret="Num5";
        break;
    case sf::Keyboard::Num6 :

        ret="Num6";
        break;
    case sf::Keyboard::Num7 :

        ret="Num7";
        break;
    case sf::Keyboard::Num8 :

        ret="Num8";
        break;
    case sf::Keyboard::Num9 :

        ret="Num9";
        break;
    case sf::Keyboard::Escape :

        ret="Escape";
        break;
    case sf::Keyboard::LControl :

        ret="LControl";
        break;
    case sf::Keyboard::LShift :

        ret="LShift";
        break;
    case sf::Keyboard::LAlt :

        ret="LAlt";
        break;
    case sf::Keyboard::LSystem :

        ret="LSystem";
        break;
    case sf::Keyboard::RControl :

        ret="RControl";
        break;
    case sf::Keyboard::RShift :

        ret="RShift";
        break;
    case sf::Keyboard::RAlt :

        ret="RAlt";
        break;
    case sf::Keyboard::RSystem :

        ret="RSystem";
        break;
    case sf::Keyboard::Menu :

        ret="Menu";
        break;
    case sf::Keyboard::LBracket :

        ret="LBracket";
        break;
    case sf::Keyboard::RBracket :

        ret="RBracket";
        break;
    case sf::Keyboard::SemiColon :

        ret="SemiColon";
        break;
    case sf::Keyboard::Comma :

        ret="Comma";
        break;
    case sf::Keyboard::Period :

        ret="Period";
        break;
    case sf::Keyboard::Quote :

        ret="Quote";
        break;
    case sf::Keyboard::Slash :

        ret="Slash";
        break;
    case sf::Keyboard::BackSlash :

        ret="BackSlash";
        break;
    case sf::Keyboard::Tilde :

        ret="Tilde";
        break;
    case sf::Keyboard::Equal :

        ret="Equal";
        break;
    case sf::Keyboard::Dash :

        ret="Dash";
        break;
    case sf::Keyboard::Space :

        ret="Space";
        break;
    case sf::Keyboard::Return :

        ret="Return";
        break;
    case sf::Keyboard::BackSpace :

        ret="BackSpace";
        break;
    case sf::Keyboard::Tab :

        ret="Tab";
        break;
    case sf::Keyboard::PageUp :

        ret="PageUp";
        break;
    case sf::Keyboard::PageDown :

        ret="PageDown";
        break;
    case sf::Keyboard::End :

        ret="End";
        break;
    case sf::Keyboard::Home :

        ret="Home";
        break;
    case sf::Keyboard::Insert :

        ret="Insert";
        break;
    case sf::Keyboard::Delete :

        ret="Delete";
        break;
    case sf::Keyboard::Add :

        ret="Add";
        break;
    case sf::Keyboard::Subtract :

        ret="Subtract";
        break;
    case sf::Keyboard::Multiply :

        ret="Multiply";
        break;
    case sf::Keyboard::Divide :

        ret="Divide";
        break;
    case sf::Keyboard::Left :

        ret="Left";
        break;
    case sf::Keyboard::Right :

        ret="Right";
        break;
    case sf::Keyboard::Up :

        ret="Up";
        break;
    case sf::Keyboard::Down :

        ret="Down";
        break;
    case sf::Keyboard::Numpad0 :

        ret="Numpad0";
        break;
    case sf::Keyboard::Numpad1 :

        ret="Numpad1";
        break;
    case sf::Keyboard::Numpad2 :

        ret="Numpad2";
        break;
    case sf::Keyboard::Numpad3 :

        ret="Numpad3";
        break;
    case sf::Keyboard::Numpad4 :

        ret="Numpad4";
        break;
    case sf::Keyboard::Numpad5 :

        ret="Numpad5";
        break;
    case sf::Keyboard::Numpad6 :

        ret="Numpad6";
        break;
    case sf::Keyboard::Numpad7 :

        ret="Numpad7";
        break;
    case sf::Keyboard::Numpad8 :

        ret="Numpad8";
        break;
    case sf::Keyboard::Numpad9 :

        ret="Numpad9";
        break;
    case sf::Keyboard::F1 :

        ret="F1";
        break;
    case sf::Keyboard::F2 :

        ret="F2";
        break;
    case sf::Keyboard::F3 :

        ret="F3";
        break;
    case sf::Keyboard::F4 :

        ret="F4";
        break;
    case sf::Keyboard::F5 :

        ret="F5";
        break;
    case sf::Keyboard::F6 :

        ret="F6";
        break;
    case sf::Keyboard::F7 :

        ret="F7";
        break;
    case sf::Keyboard::F8 :

        ret="F8";
        break;
    case sf::Keyboard::F9 :

        ret="F9";
        break;
    case sf::Keyboard::F10 :

        ret="F10";
        break;
    case sf::Keyboard::F11 :

        ret="F11";
        break;
    case sf::Keyboard::F12 :

        ret="F12";
        break;
    case sf::Keyboard::F13 :

        ret="F13";
        break;
    case sf::Keyboard::F14 :

        ret="F14";
        break;
    case sf::Keyboard::F15 :

        ret="F15";
        break;
    case sf::Keyboard::Pause :

        ret="Pause";
        break;
    case sf::Keyboard::KeyCount :

        ret="KeyCount";
        break;


    default:
        ret="Unknow";
        break;
        }
    return ret;






}

[Laurent]

As already said, you can avoid all this code duplication with a macro:

#define ITEM(x) case sf::Keyboard:: ## x : ret = #x; break;
switch (k)
{
    ITEM(A)
    ITEM(B)
    ...
}

[ChronicRat]

As already said, you can avoid all this code duplication with a macro:

Or use static array static const std::string KEY_NAMES[sfKeyboard::KeyCount] = {"A", "B", "C" ... };

[Laurent]

Or use static array static const std::string KEY_NAMES[sfKeyboard::KeyCount] = {"A", "B", "C" ... };

This it not reliable nor efficient: key codes may not be a contiguous range of indices, and they may change in the future.

[Nexus]

And there's no reason to use break and a variable, just directly return the values. And fix your empty lines, statements are grouped in a confusing way

By the way, I hope you didn't write all this code manually? When you copy/paste an existing list of all the enumerators and use a regex, you can setup the whole switch statement in a matter of seconds...

[ChronicRat]

This it not reliable nor efficient: key codes may not be a contiguous range of indices, and they may change in the future.

Yes surely, but for now it will work fine and a little bit faster.

[Hiura]

@ChronicRat that's a premature optimization! And on what argument do you base your conclusion? I wouldn't be too surprise if a switch is faster because of cache miss and jump prediction (to mention only those); everything could happen. Ask a profiler if you're curious to know the truth. 

[Laurent]

a little bit faster

A don't think anybody cares about the nanosecond we'll save here. So this is really a non-argument

[ChronicRat]

May be i wrong, yes. And i agree, this function has no need to be called per frame. =)