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I'm having problems with KeyHit that Gernot created. I want to press a key and start a sprite moving. I don't want the sprite to stop until I press the same key again. What I do doesn't seem to work. Here's the code. Thanks for any info.

KeyHitUpdate()

IF KeyHit(57) = 2
    locX = locX + dirX
ELSE
    locX = locX
ENDIF


Gernots keyhit has multiple status', perhaps you arent using the correct one?

However, in case you cant get that to work for your needs, i have different key hit sample here.
The trick with this function is it always returns -1, except when a key is initially pressed.
When a key is hit initially, it will return the key code number, for this frame only.
Basically, it is a "light" version of Keyhit sample, with much less options.
It is specialized for only operating during that initial key hit.
One thing to note: The function scans key codes 0 through 220, you might want to tinker with this, if it isnt scanning the your button code.



WHILE TRUE

KeyPressed=KeyBoardIO()

IF KeyPressed=57
IsSpriteMoving=IsSpriteMoving+1
IF IsSpriteMoving>1 THEN IsSpriteMoving=0
ENDIF

//this is just a sample of a moving sprite:
IF IsSpriteMoving=1 THEN angle=angle+1
x=200+COS(angle)*100
y=200+SIN(angle)*100
PRINT "Player1",x,y

PRINT "Press Space to Start/Stop Movement",10,10
SHOWSCREEN

WEND



// KeyBoardIO() will always return -1, except when a key is hit, return that key code one time.
FUNCTION KeyBoardIO:

LOCAL KeyIndex
LOCAL IsKeyPressed=0
LOCAL IsKeyLocked=1

//Prepare the memory:
STATIC INITIALIZE
IF INITIALIZE=FALSE; INITIALIZE=TRUE;
DIM KeyBuffer[221][2]
KeyBuffer[0][0]=0
ENDIF

//Check all key holding states:
FOR KeyIndex=0 TO 220
IF KEY(KeyIndex)
KeyBuffer[KeyIndex][IsKeyPressed]=TRUE //Key pressed for the first time.
IF KeyBuffer[KeyIndex][IsKeyLocked]=FALSE
KeyBuffer[KeyIndex][IsKeyLocked]=TRUE
RETURN KeyIndex
ENDIF
ELSE
KeyBuffer[KeyIndex][IsKeyPressed]=FALSE //Key held
KeyBuffer[KeyIndex][IsKeyLocked]=FALSE
ENDIF
NEXT
RETURN -1 //dont send anything
ENDFUNCTION


Quote from: quick2code on 2009-Nov-10
I'm having problems with KeyHit that Gernot created. I want to press a key and start a sprite moving. I don't want the sprite to stop until I press the same key again. What I do doesn't seem to work. Here's the code. Thanks for any info.

Code (glbasic) Select Expand


KeyHitUpdate()
global move% = 0   // This will store the state we are in. 0 for still, -1 for moving

IF KeyHit(57) = 2  // If user pressed key, start movement
    move = bNOT(move)   // This will alternate between 0 and -1
ENDIF

IF move = -1          // If key was pressed earlier sometime, keep moving
    locX = locX + dirX
ENDIF


You are using the KeyHit correctly but you need to save the state somewhere when the user hits the button. See the changed code above

Thank you kindly gentlemen.