/// <summary>
/// Compares two nodes and returns a value indicating whether the first node's
/// distance to the point is less than, equal to or greater than the second
/// node's distance to the specified point.
/// </summary>
/// <param name="o1">The first node to compare.</param>
/// <param name="o2">The second node to compare.</param>
/// <returns>
/// Less than 0, if o1's distance to the point is less than o2's distance to the
/// point; 0 if o1's distance to the point equals 02's distance to the point;
/// greater than 0 if o1's distance to the point is greater than o2's distance to
/// the point.
/// </returns>
public int Compare(object o1, object o2)
{
PNode each1 = (PNode)o1;
PNode each2 = (PNode)o2;
PointF each1Center = PUtil.CenterOfRectangle(each1.GlobalFullBounds);
PointF each2Center = PUtil.CenterOfRectangle(each2.GlobalFullBounds);
if (!NODE_TO_GLOBAL_NODE_CENTER_MAPPING.Contains(each1))
{
NODE_TO_GLOBAL_NODE_CENTER_MAPPING.Add(each1, each1Center);
}
if (!NODE_TO_GLOBAL_NODE_CENTER_MAPPING.Contains(each2))
{
NODE_TO_GLOBAL_NODE_CENTER_MAPPING.Add(each2, each2Center);
}
float distance1 = PUtil.DistanceBetweenPoints(point, each1Center);
float distance2 = PUtil.DistanceBetweenPoints(point, each2Center);
if (distance1 < distance2)
{
return(-1);
}
else if (distance1 == distance2)
{
return(0);
}
else
{
return(1);
}
}
/// <summary>
/// Returns true if a drag sequence should be initiated.
/// </summary>
/// <param name="e">A PInputEventArgs that contains the event data.</param>
/// <returns>True if a drag sequence should be initiated; otherwise, false.</returns>
protected virtual bool ShouldStartDragInteraction(PInputEventArgs e)
{
return(PUtil.DistanceBetweenPoints(MousePressedCanvasPoint, e.CanvasPosition)
>= MinDragStartDistance);
}