This is more or less a 'hack' but atleast it works:
SuperStrict
Type TVect2
Field x:Float, y:Float
Method Create:TVect2(_x:Float,_y:Float)
Local v:TVect2 = New TVect2
v.x = _x
v.y = _y
Return v
End Method
Method GetX:Float()
Return x
End Method
Method GetY:Float()
Return y
End Method
Method SetX(_x:Float)
x = _x
End Method
Method SetY(_y:Float)
y = _y
End Method
Method GetAngle:Float()
Return ATan2(y,x)
End Method
Method Rotate(ang:Float)
Local xprime:Float=Cos(ang)*x - Sin(ang)*y
Local yprime:Float=Sin(ang)*x + Cos(ang)*y
x=xprime
y=yprime
End Method
Method Add(_x:Float,_y:Float)
x:+_x
y:+_y
End Method
Method AddVec(Vec:TVect2)
If Vec=Null Return
x:+Vec.x
y:+Vec.y
End Method
Method Subtract(_x:Float,_y:Float)
x:-_x
y:-_y
End Method
Method SubtractVec(Vec:TVect2)
If Vec=Null Return
x:-Vec.x
y:-Vec.y
EndMethod
Method Multiply(_x:Float,_y:Float)
x:*_x
y:*_y
EndMethod
Method MultiplyVec(Vec:TVect2)
If Vec=Null Return
x:*Vec.x
y:*Vec.y
EndMethod
Method Divide(_x:Float,_y:Float)
If _x = 0 Or _y = 0 Return
x:/_x
y:/_y
EndMethod
Method DivideVec(Vec:TVect2)
If Vec=Null Return
x:/Vec.x
y:/Vec.y
EndMethod
End Type
AppTitle = "Ball Vector example"
Graphics 800 , 600
Local ballx:Float = 400
Local bally:Float = 550
Local ballvector:TVect2 = New TVect2.Create(1 , - 8)
Local gravity:TVect2 = New TVect2.Create(0 , .1)
Local bounceloss:TVect2 = New TVect2.Create(0 , 1)
While Not KeyHit(KEY_ESCAPE)
Cls
If bally > 580 Then
bally = 580 ' once it's past this point just set it to the floor.
ballvector.Rotate(180)
Local mag:Float = (ballVector.x * ballVector.x + ballVector.y * ballVector.y)
If mag < 1.5 * 1.5 Then ' if the ball's velocity hits a certain minimum point just set it to zero to avoid 'vibrations'
ballvector.x = 0
ballvector.y = 0
End If
ballvector.AddVec(bounceloss)
End If
ballvector.AddVec(gravity)
ballx:+ ballvector.GetX()
bally:+ ballvector.GetY()
DrawOval ballx,bally,10,10
Flip 1
Wend
A more 'proper' way would be to check for collisions before you move the ball's x/y position. You'd basically:
1. find the point of collision from the ball's position + ball's vector. 2. Set the ball there, and the 'remainder' of what ever the ball's vector is, you set it as the 'reflection. i.e. if the collision happened half way along the vector, then move the ball half way along that vector, then the remaining half you use to 'reflect' the ball.
3. rinse, repeat.
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