Probably everyone is familiar with all kinds of visual node based programming tools like HLSL editor in Visual Studio 2011 or UDK engine Kismet/Material editors. My point of interest are the connectors between the nodes. Basically those are implementation of Bezier Curve algorithms. Those are not hard to put into code.
How I make each connector line bend into right direction and with the right angle when it is being connected between two points not laying on the same line?