SFML community forums

General => Feature requests => Topic started by: dd on October 30, 2024, 11:03:43 pm

Title: Overload of sf::Keyboard::isKeyPressed allowing input of vector of keys
Post by: dd on October 30, 2024, 11:03:43 pm

Usually, in my games, I have a list of these ifstatements:

if (sf::Keyboard::isKeyPressed(sf::Keyboard::Up) || sf::Keyboard::isKeyPressed(sf::Keyboard::W))
    // Stuff
}

(Or something similar)

Now yes, while this does work, it doesn't exactly look very neat, and sometimes, when I map over 3 keys to a single input, the line wraps and looks very messy.
A good fix would be to create an overload of the sf::Keyboard::isKeyPressed() function allowing for the input of a vector (or some other form of array) of keys. For example:

 std::vector<sf::Keyboard> Keys = {sf::Keyboard::A, sf::Keyboard::D, sf::Keyboard::W, sf::Keyboard::S};
if (sf::Keyboard::isKeyPressed(Keys)){
    //stuff
}

And this would have the same effect of this:

if (sf::Keyboard::isKeyPressed(sf::Keyboard::A) || sf::Keyboard::isKeyPressed(sf::Keyboard::D, sf::Keyboard::isKeyPressed(sf::Keyboard::W) || sf::Keyboard::isKeyPressed(sf::Keyboard::S))){
    // Stuff
}

Yes, this feature doesn't greatly impact the actual framework much, but overall it just makes code much cleaner and easier to read.

Title: Re: Overload of sf::Keyboard::isKeyPressed allowing input of vector of keys
Post by: eXpl0it3r on October 30, 2024, 11:18:12 pm

It's highly recommended to use events to track inputs in most cases. Polling the "hardware" isn't very efficient and some systems require additional permissions (e.g. macOS requires monitoring permission).

There are a lot of ways to handle key mappings - Thor for example used an useful action map (https://bromeon.ch/libraries/thor/tutorials/v2.0/actions.html) - as such SFML leaves this to the user or extension libraries.
The philosophy for SFML (https://www.sfml-dev.org/contribute.php#general-considerations) is to provide the cross-platform API on which people can build their systems.

Title: Re: Overload of sf::Keyboard::isKeyPressed allowing input of vector of keys
Post by: Garwin on November 01, 2024, 12:23:44 pm

You can use variadic templates but is quite unsafe.
I did not check the code, hope it is correct.

auto isAnyKeyPressed(auto... keys) -> bool
{
    return (sf::Keyboard::isKeyPressed(keys) || ...);
}
 

Now you can use just:

if (isAnyKeyPressed(sf::Keyboard::A, sf::Keyboard::D, sf::Keyboard::W, sf::Keyboard::S))
    // make stuff there

 

Problem with the code is:
1. It does not check type of arguments but at least it will generate errors if any parameter is not convertible to enum sf::Keyboard::Key
2. It has even more issues as sf::Keyboard::Key is unscoped enum which can make error messages even tougher to get to the point of error. And it can accept even incorrect parameter.

You can limit template with Concept but issue of unscoped Enum remains.