[Gambas-user] angle interpolation algorithm troubles

[Kevin Fishburne]

Apparently I'm too much of a dummy to figure this out. I have two 
singles representing orientation in degrees, let's say Angle1 and 
Angle2. I need to continually increment one (let's say Angle1) until 
it's close to the value of the other (Angle2), but in the direction of 
the shortest distance between the two angles.

So if Angle1 = 10 and Angle2 = 350, Angle1 should be repeatedly 
decremented, wrapping around the upper limit of 360 (10, 5, 0, 355, 
350). If Angle1 was 350 and Angle2 was 20, Angle1 would be incremented 
like 350, 355, 0, 5, 10, 15, 20. I have a crude function to wrap a 
number which may be of use:

Public Function Wrap_Single(Minimum As Single, Maximum As Single, Value 
As Single) As Single

   ' Constrain value to specified range.

   ' General declarations.
   Dim Spread As Single = Maximum - Minimum + 1  ' Range between minimum 
and maximum values.

   ' Wrap if value is too large.
   If Value > Maximum Then
     Do
       Value = Value - Spread
     Loop Until Value <= Maximum
   Endif

   ' Wrap if value is too small.
   If Value < Minimum Then
     Do
       Value = Value + Spread
     Loop Until Value >= Minimum
   Endif

   ' Return wrapped value.
   Return Value

End

This is my current code, which works except the Distance variable isn't 
doing its job:

' Check if camera orientation is locked to client player orientation.
If Camera.Locked Then
   ' Check if difference in orientations exceeds interpolation threshold.
   Distance = Abs(Camera.Orientation - 
Client.Player[Client.Number].Orientation)
   If Distance >= 5.625 Then
     ' Move camera orientation closer to player orientation (interpolate).
     If Camera.Orientation - Client.Player[Client.Number].Orientation < 
Client.Player[Client.Number].Orientation - Camera.Orientation Then
       Camera.Orientation = Convert.Wrap_Single(0, 359, 
Camera.Orientation + 0.1 * Distance)
     Else
       Camera.Orientation = Convert.Wrap_Single(0, 359, 
Camera.Orientation - 0.1 * Distance)
     Endif
   Endif
Endif

My instinct tells me I'm almost there but am missing one critical thing. 
If someone smarter than myself instantly sees my mistake please let me 
know. :)

-- 
Kevin Fishburne
Eight Virtues
www: http://sales.eightvirtues.com
e-mail: sales at ...1887...
phone: (770) 853-6271