Getting output on MULTIPLE screens?

BlitzMax Forums/BlitzMax Programming/Getting output on MULTIPLE screens?

Newbie

(Posted 2007) [#1]

Does blitz support dual-screen support? how would I achieve that?

scenario: I have a computer with 2 graphics cards, and of course two seperate monitors allowing me to drag and drop files from one monitor to the other etc.

Can I in Blitz code my way around to have Blitz show one graphics() on one monitor and another graphics() on the other monitor?

technically, it SHOULD be possible, right? I mean, Blitz is using DirectX, and DirectX supports it through Windows, so Max should somehow be able to tap into that, right?

Any ideas?

Damien Sturdy

(Posted 2007) [#2]

I think max only uses one instance, however if you use maxGUI or other techniques you can program it to work. I've not done it myself though.

LAB[au]

(Posted 2007) [#3]

If you use windowed mode then it's no big deal, just set windows to "extend my desktop on this monitor" and in max open a "bigger" widow, you can even make it fullscreen without borders/menu/status.

Here is the function I use for that

Function SetWindowFullscreen:Int(Window:TGadget)

	Extern "Win32"
		Function SetWindowLongA:Int(hWnd:Int, nIndex:Int, dwNewLong:Int)="SetWindowLongA@12"
		Function SetLayeredWindowAttributes(hWnd:Int, temp:Int, alpha:Int, buh:Int)="SetLayeredWindowAttributes@16"
		Function GetWindowLongA:Int(hWnd:Int, nIndex:Int)="GetWindowLongA@8"
		Function MoveWindow:Int(hwnd:Int, x:Int, y:Int, nWidth:Int, nHeight:Int, bRepaint:Int)="MoveWindow@24"
		Function GetSystemMetrics:Int (nIndex:Int) = "GetSystemMetrics@4"
		Function SetWindowPos:Int (hwnd:Int, hWndInsertAfter:Int, x:Int, y:Int, cx:Int, cy:Int, wFlags:Int) = "SetWindowPos@28"
	End Extern

	Local hWnd:Int
	Local Style:Int
   
	hWnd = QueryGadget(Window, QUERY_HWND)
   
	If Not hWnd
		Return False
	EndIf
   
   'Style = GetWindowLongA(hWnd, GWL_STYLE)
   'Style:|WS_EX_LAYERED
   
	Const SM_XVIRTUALSCREEN:Int       =76
	Const SM_YVIRTUALSCREEN:Int       =77
	Const SM_CXVIRTUALSCREEN:Int      =78
	Const SM_CYVIRTUALSCREEN:Int      =79
	Const SM_CMONITORS:Int            =80
	Const SM_SAMEDISPLAYFORMAT:Int    =81
	
	Style = WS_VISIBLE
	
	Local window_w:Int = GetSystemMetrics(SM_CXVIRTUALSCREEN)
	Local window_h:Int = GetSystemMetrics(SM_CYVIRTUALSCREEN)
	ReleaseCapture()
	SetWindowLongA(hWnd, GWL_STYLE, Style)

	MoveWindow(hWnd, (GetSystemMetrics(SM_CXVIRTUALSCREEN) - window_w) / 2, (GetSystemMetrics(SM_CYVIRTUALSCREEN) - window_h) / 2, window_w, window_h, 1)
	Return True

End Function

If you want to have it fullscreen (real fullscreen) you can do it by passing the dual screen resolution to "graphics" function, altough it will work only if this dualscreen is setup on a single graphic card with dual output, I have been testing that only on NVidia cards. If you have multiple graphic cards then you have no other choice than using windowed mode with "fake" fullscreen.

Newbie

(Posted 2007) [#4]

I do have MaxGUI, are you saying with that it's possible somehow?? but MAX gui does not support fullscreen does it? but I guess that doesnt mean I cant open a Windows of max. resolution, right? (rather 2 Windows of max resolution) and disable the icons such as "X" etc. to "simulate" fullscreen?

Newbie

(Posted 2007) [#5]

@LAB[au]

are you saying i can open one MaxGUI window that is say a pong game on one monitor, and another MaxGUI Window that is a breakout game, and both games will play independantly?

Newbie

(Posted 2007) [#6]

anyone else who has experience with this stuff :-)?

LAB[au]

(Posted 2007) [#7]

You can open a "2 screen" window, with 2 canvases, or you can open 2 .exe, one with pong the other with breakout.

In both cases you will have to mess around with win api calls, like in the example function above.

GetSystemMetrics with all the constants listed above will give you basically what you need as information, like the number of monitors, the desktop resolution when using dualscreen (or more),...

Maxgui doesn't support fullscreen, but win api can fake it, the above function maximize your window and place it above all, so that it looks like fullscreen.

If you maximize a window with Maxgui it will max to the first screen (not expand to the 2 screens), the tricks is to use some win api calls, with the "Virtualscreen" constants.

Scaremonger

(Posted 2007) [#8]

You don't need MAXGUI or API's to create 2 windows. Blitz can do it anyway... (These are created on top of each other so you need to move the top one out of the way)

Try this code (Pressing space draws a BIG oval)


Local screen:TGraphics[2]
Local x:Double[2,2] , y:Double[2,2]
Global quit% = False
EnablePolledInput()

screen[0] = CreateGraphics( 200 , 200, 0, 60, 0 )
screen[1] = CreateGraphics( 300 , 300, 0, 60, 0 )
x[0 , 1] = 1
y[0 , 1] = 1.5
x[1 , 1] = 1
y[1 , 1] = 1.5


AddHook systemEventHook , _hook

While Not quit
	
	For Local n = 0 To 1
		SetGraphics( screen[n] )
		x[n , 0] :+ x[n , 1]
		y[n , 0] :+ y[n , 1]
		If x[n , 0] > GraphicsWidth() Or x[n , 0] < 1 Then x[n , 1] = - x[n , 1]
		If y[n , 0] > GraphicsHeight() Or y[n , 0] < 1 Then y[n , 1] = - y[n , 1]
		Cls
		DrawText("O" , x[n , 0] , y[n , 0] )
		SetColor 255,255,255
		If KeyDown(KEY_SPACE) And n=1 Then DrawOval 0 , 0 , 640 , 480
		Flip
	Next
	
Wend

Function _Hook:Object(iId:Int,tData:Object,tContext:Object)
Local Event:TEvent = TEvent(tData)
If Event.ID <> EVENT_MOUSEMOVE Then Print "[" + Event.ID + "] " + Event.ToString()
If event = Null Then Return tData
	Select event.id
	Case EVENT_APPTERMINATE
		quit = True
	End Select
Return tData
End Function