procedure TMainForm.SetCameraDistance(Distance: Single);
begin
  fCameraDistance := Distance;

  // To be at 45 degrees to the map we'll need to offset two coords by this much:
  var Offset := Distance / Sqrt(2);

  // And we can work out how high we need to be at this distance to be looking at 0, 0, 0
  var Height := Distance * Tan(DegToRad(30));

  // Rotate and move camera so it is looking 45 degrees around and 30 degrees down
  // and set the view angle to a very small value to remove perspective
  Camera.RotationAngle.Point := TPoint3D.Create(-30, 45, 0);
  Camera.Position.Point := TPoint3D.Create(-Offset, -Height, -Offset);
  Camera.AngleOfView := 1;
end;