One of the least flexible things in C4D are the options available for creating straight lines with the Spline Tool.
Usually applications will let you constrain on an axis by holding down the shift key, which in turn will draw straight lines. This is not so, with Cinema 4D.
Of course you could snap to the grid to create straight lines, but are there other, more convenient ways?
There are. Vic Garcia (Facade) shows how you can quickly create straight lines with the spline tool in C4D without having to snap to the grid every time.