polled input sticking

Archives Forums/BlitzMax Bug Reports/polled input sticking

Nigel Brown

(Posted 2006) [#1]

When holding a key down continuously the key eventually stops returning its pressed state until you release and press again?

I am running in windowed mode. And calling enablepolledinput() All works fine under Windows and OSX but not Linux.

Here is an example of the problem, use the left arrow key to change screen colour.

Also if you change KEY_LEFT to KEY_ESCAPE then nothing ever happens?

Const WINDOW_WIDTH=640
Const WINDOW_HEIGHT=384

Local wx=(GadgetWidth(Desktop())-WINDOW_WIDTH)/2
Local wy=(GadgetHeight(Desktop())-WINDOW_HEIGHT)/2
Global main_window:TGadget = CreateWindow( Title$,wx,wy,WINDOW_WIDTH,WINDOW_HEIGHT,Null,WINDOW_TITLEBAR | WINDOW_CLIENTCOORDS)
Global canvas:TGadget=CreateCanvas(0,0,WINDOW_WIDTH,WINDOW_HEIGHT,main_window)
SetGraphics CanvasGraphics(canvas)

ActivateGadget canvas

CreateTimer(10)

enablepolledinput()

While WaitEvent()

	Select	EventID()

		Case EVENT_WINDOWCLOSE
			End

		Case EVENT_TIMERTICK

			If KeyDown(KEY_LEFT)
				SetClsColor Rnd(255),Rnd(255),Rnd(255)
				Cls
				Flip
			EndIf

	EndSelect

End While

Nigel Brown

(Posted 2006) [#2]

Problem is not just with polled input. Here is another example but this time using EVENT_KEYDOWN and EVENT_KEYUP hold a key down and watch the KEYUP event being generated?

Const WINDOW_WIDTH=640
Const WINDOW_HEIGHT=384

Global hit[1024]

Function MyKeyDown( key:Int )
	Return HIT[Key]
End Function

Local wx=(GadgetWidth(Desktop())-WINDOW_WIDTH)/2
Local wy=(GadgetHeight(Desktop())-WINDOW_HEIGHT)/2
Global main_window:TGadget = CreateWindow( Title$,wx,wy,WINDOW_WIDTH,WINDOW_HEIGHT,Null,WINDOW_TITLEBAR | WINDOW_CLIENTCOORDS)
Global canvas:TGadget=CreateCanvas(0,0,WINDOW_WIDTH,WINDOW_HEIGHT,main_window)
SetGraphics CanvasGraphics(canvas)

ActivateGadget canvas

CreateTimer(10)

'enablepolledinput()

While WaitEvent()

	Select	EventID()

		Case EVENT_WINDOWCLOSE
			End

		Case EVENT_KEYUP
			DebugLog "KEY UP"
			Select EventData()
				Case KEY_LEFT
					HIT[KEY_LEFT]=0
			End Select
			
		Case EVENT_KEYDOWN
			DebugLog "KEY DOWN"
			Select EventData()
				Case KEY_LEFT
					HIT[KEY_LEFT]=1
			End Select

		Case EVENT_TIMERTICK

			If MyKeyDown(KEY_LEFT)
				SetClsColor Rnd(255),Rnd(255),Rnd(255)
				Cls
				Flip
			EndIf

	EndSelect

End While

Nigel Brown

(Posted 2006) [#3]

See this thread for further exploration:

http://www.blitzbasic.com/Community/posts.php?topic=65197

JoshK

(Posted 2007) [#4]

My spacekey is sticking in Windows XP.

computercoder

(Posted 2007) [#5]

I doubt this will resolve this issue, but if you are using a USB KVM, the KVM will make keys "stick" like this. I resolved this by not sharing the components when I need the polling more responsive.