Converting key into integer value

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pinseventy

Converting key into integer value

in General Discussion • Other • 4 months ago

Hey everybody, I've been searching all over for the answer to this, so I hope that by asking it here I will finally get what I am looking for.

I am simply curious if it is possible to convert the value of key to a numerical value. I figured it might be some sort of ASCII number, but I still can't figure this out. I know it would be possible with a disgusting amount of if-statements, but I would love to avoid that if at all possible.

Thanks in advance,

-PinSeventy

Replies(5)

v.k.

Re: Converting key into integer value

4 months ago

you mean

void draw(){}
void keyReleased(){
println(int(key));
}

GoToLoop

Re: Converting key into integer value

4 months ago

Variable key is already an integral numerical value! More specifically, a data-type char.

Which is an unsigned 16-bit value (0 - 65535 or 2^16 - 1).

However, when a char value is meant to be displayed, rather than its numerical value,

a representation of its ASCII / Unicode character is shown instead!

That's why a conversion is needed when you want to see its true numerical value.

Usually, an (int) cast operator is the fastest and simple way for it -> println( (int) key );

As long as you don't need negative numbers, and it's confined between 0 - 65535,

a char variable can use any Java operator as any other type!

v.k.

Re: Converting key into integer value

4 months ago

What I got confused is that if you look at a UTF-8 table for, lets say 'a', it will say the code is: 61 or U+0061, but the code above will print 97... which happens to be decimal for hex 61... as I learned in a question at StackOverflow, so you can say:

void draw() {
}
void keyReleased() {
char k = key;
print("char " + key + " = ");
print(" decimal " + (int)key + " = ");
println("hexadecimal " + hex(int(k)) );
}

GoToLoop

Re: Converting key into integer value

4 months ago

Java uses UNICODE-16 (UTF-16).

And as I've mentioned above, char is a a fully integral numerical data-type as byte, short, int & long are!

There are 2 peculiarities though:

It's the only Java's unsigned data-type.
It displays itself as Unicode-16 characters.

So, @ line #7, the converters int() function or (int) cast operator are redundant:

println( "hexadecimal " + hex(key) );

v.k.

Re: Converting key into integer value

4 months ago

great, thanks :)

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