Zoom View

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Haramanai

Well...
I found a way that it works with GLMax2D.
It's pure OpenGL.
I named the function setCenterAndZoom

Function setCenterAndZoom(x:Float , y:Float , Zoom:Float)
	Local LeftGL:Float = x - ((GraphicsWidth() / Zoom) / 2)
	Local RightGL:Float = x + ((GraphicsWidth() / Zoom) / 2)
	Local ButtomGL:Float = y + ((GraphicsHeight() / Zoom) / 2)
	Local TopGL:Float = y - ((GraphicsHeight() / Zoom) / 2)	
	glMatrixMode 	(GL_PROJECTION)
	glLoadIdentity	()
	gluOrtho2D		(LeftGL, RightGL, ButtomGL,TopGL)
End Function

and here it's an example... with Max2D Drawing

SuperStrict

SetGraphicsDriver GLMax2DDriver()

Graphics 640 , 480

Local Zoom:Float = 1.0
Local CenterX:Float = 0.0
Local CenterY:Float = 0.0
While Not KeyDown(KEY_ESCAPE)
	Cls
	setCenterAndZoom( CenterX , CenterY , Zoom )
	
	SetColor 0 , 255 , 0
	DrawOval 30 , 30 , 40 , 40
	SetColor 255 , 0 , 0
	DrawLine 0 , 0 , 30 , 30
	
	If KeyDown(KEY_LEFT) Then CenterX:-1
	If KeyDown(KEY_RIGHT) Then CenterX:+1	
	If KeyDown(KEY_UP) Then CenterY:-1	
	If KeyDown(KEY_DOWN) Then CenterY:+1		
	If KeyDown(KEY_NUMADD) Then Zoom:+ 0.1
	If Zoom > 0.1
		If KeyDown(KEY_NUMSUBTRACT) Then Zoom:- 0.1	
	End If
			
	Flip
Wend

Function setCenterAndZoom(x:Float , y:Float , Zoom:Float)
	Local LeftGL:Float = x - ((GraphicsWidth() / Zoom) / 2)
	Local RightGL:Float = x + ((GraphicsWidth() / Zoom) / 2)
	Local ButtomGL:Float = y + ((GraphicsHeight() / Zoom) / 2)
	Local TopGL:Float = y - ((GraphicsHeight() / Zoom) / 2)	
	glMatrixMode 	(GL_PROJECTION)
	glLoadIdentity	()
	gluOrtho2D		(LeftGL, RightGL, ButtomGL,TopGL)
End Function

please test...