Best way to flip an integer between 1 and 0

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Glyn

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Location: Shropshire, UK

Posted: 21st Feb 2018 23:58

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Hi there all

New to this programming language and I was wondering if there was a way to to flip a integer between 1 and 0 other than using an IF-ELSE like the following please?

+ Code Snippet

if GetRawKeyPressed(KEY_B)
	if Brakes_On = 1
		Brakes_On = 0
	elseif Brakes_On = 0
		Brakes_On = 1
	endif
PlaySound(brake-noise)
endif

Many thanks

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MillaSays

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Posted: 22nd Feb 2018 10:39

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Umm, well, AppGameKit is missing some nice things from other languages, like boolean type (you have to use integer) but the AppGameKit integer is magic, and doubles as a boolean...

So try this code:

+ Code Snippet

bit as integer = 0

bit = flipBit(bit)

do
	Print("flipped: " + str(bit))
	Sync()
loop

function flipBit(in)
	out = not in
endFunction out

Mind you, only an initial value of 0 will result in a 1, any other value will result in a 0.

In your code, you'd do something like this:

+ Code Snippet

if GetRawKeyPressed(KEY_B)
    Brakes_On = not Brakes_On
    PlaySound(brake-noise)
endif

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GarBenjamin

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Posted: 22nd Feb 2018 10:48 Edited at: 22nd Feb 2018 10:50

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Brakes_On = 1 - Brakes_On

1 - 0 = 1
1 - 1 = 0
I use this in any programming language.

TI/994a (BASIC) -> C64 (BASIC/PASCAL/ASM/Others) -> Amiga (AMOS/BLITZ/ASM/C/Gamesmith) -> DOS (C/C++/Allegro) -> Windows (C++/C#/Monkey X/GL Basic/Unity/Others)

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Santman

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Posted: 22nd Feb 2018 11:52 Edited at: 22nd Feb 2018 11:53

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Depending on how often ypu do it, in T1 i can't see anything wrong with what you're doing, it'll happen perfectly quickly and I do solar all the time myself.

Gar, had to read that a ew times.....but that's a nice little trick there.

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Zep

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Location: From PA, USA. Currently reside in Hanoi, Vietnam

Posted: 22nd Feb 2018 14:01

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if GetRawKeyPressed(KEY_B)
if Brakes_On = 1
Brakes_On = 0
elseif Brakes_On = 0
Brakes_On = 1
endif
PlaySound(brake-noise)
endif

Your brake-noise is going to play if the breaks are off OR on with that code. (or any time KEY_B is pressed, basically)

I don't know...maybe that's your intention? Doesn't look right to me...

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CJB

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Posted: 22nd Feb 2018 14:12

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Maybe this: (checks if the key is held down)

+ Code Snippet

if GetRawKeyState(KEY_B)
    if Brakes_On = 0
        Brakes_On = 1
        PlaySound(brake-noise)
    endif
endif
if GetRawKeyRelease(KEY_B)
   Brakes_On = 0
endif

Aaargh! Ducks!
Phone Tap!
Uzmadesign

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IronManhood

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Posted: 22nd Feb 2018 14:50

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You don't really need else if. I usually just make some true/false constants for pseudo booleans.

+ Code Snippet

#constant true	1
#constant false 0

if GetRawKeyPressed(KEY_B)
    if Brakes_On = true
        Brakes_On = false
    else
        Brakes_On = true
    endif
PlaySound(brake-noise)
endif

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Ortu

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Posted: 22nd Feb 2018 15:32

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I use the same method GarBenjamin uses.

http://games.joshkirklin.com/sulium

A single player RPG featuring a branching, player driven storyline of meaningful choices and multiple endings alongside challenging active combat and intelligent AI.

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Rick Nasher

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Posted: 22nd Feb 2018 16:06

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GarBenjamin's is the common practice afaik. I never used anything else since first needed it a loooong time ago.

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Dybing

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Posted: 22nd Feb 2018 17:15 Edited at: 22nd Feb 2018 18:09

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Normally, the not method is used for a single flip, as in

myBool = not myBool

or in more mainstream C like languages

myBool = !myBool

If wanting to get fancy, one can flip an entire byte - or a single bit in a byte - using XOR, which I'm not entirely sure of how is done in AppGameKit (or why you'd do it), but in C like languages

myByte ^= 0x11111111

Where each 1 in 0x11111111 will flip a bit, and a 0 will let myByte remain at whatever value it was at in the given position. Comes in very handy when doing Arduino programming and manhandling the IO registers directly. But I suppose that is a bit out of the scope of this little discussion

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Glyn

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Posted: 22nd Feb 2018 17:45

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Thanks very much guys - I will probably use GarBenjamin's method as that cuts down on typing.

Yep it is for a parking brake, so it needs to toggle and play the sound when the user presses the B key...

Cheers

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Lucas Tiridath

AGK Developer

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Posted: 22nd Feb 2018 20:50

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Funny, I've always done it like this.

Brakes_On = (Brakes_On + 1) && 1

I like the look of GarBenjamin's approach though, so might use it in future.

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PSY

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Posted: 23rd Feb 2018 13:18 Edited at: 23rd Feb 2018 13:19

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I also do it like GarBenjamin

Quote: "foo = 1 - foo"

you can also do

Quote: "foo = not foo"

In this case,
if foo is anything <>0, let's say 1337, it will switch to 0, then toggle between 1 and 0
if foo is initially 0, it will switch to 1, then toggle between 0 and 1