Bounching ball

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Jesse

here:

Graphics 800,600,0

Cls
' Create our ball
DrawOval 0,0,20,20
Global img_ball=CreateImage(21,21,1,DYNAMICIMAGE|MASKEDIMAGE)
GrabImage img_ball,0,0

Cls
' Create our rectangle
DrawRect 0,0,220,160
Global img_rect=CreateImage(220,160,1,DYNAMICIMAGE|MASKEDIMAGE)
GrabImage img_rect,0,0
AutoMidHandle True

Global spd:Float=6
Global x:Float
Global y:Float
Global angl:Float = 90;

SeedRnd MilliSecs()
x=Rand(10,100)
y=Rand(10,100)

Global cx:Float=GraphicsWidth()/2-ImageWidth(img_rect)/2
Global cy:Float=GraphicsHeight()/2-ImageHeight(img_rect)/2
Global angle:Float=45

Local dx:Float = Cos(angle) * spd
Local dy:Float = Sin(angle) * spd

Repeat
	Cls
	ResetCollisions
	DrawImage img_ball,x,y,0
	' Bounch walls
	If (x+dx)<10 Or x+dx>GraphicsWidth()-10 Then dx = - dx 
	If (y+dy)<10 Or y+dy>GraphicsHeight()-10 Then dy = - dy
	If ImagesCollide2(img_rect,cx,cy,0,0,1,1,img_ball,x+dx,y,0,0,1,1) dx = - dx
	If ImagesCollide2(img_rect,cx,cy,0,0,1,1,img_ball,x,y+dy,0,0,1,1) dy = - dy
	x:+ dx
	y:+ dy
	DrawImage img_rect,cx,cy,0
	Flip 1

Until MouseHit(1)

Function Ang:Float(x1:Float,y1:Float,x2:Float,y2:Float)
	Local dx:Float=x1-x2
	Local dy:Float=y1-y2
	Return ATan2(dy,dx)
End Function

this approach only works with horizontal and vertical contacts. If you are going to do different angle contact, you are going to have to find a different approach. Your best option is to use vectors but This should suffice for your sample code.