rotate in dc-path%
Adjusts all points within the path (including all sub-paths), rotating
them radians counter-clockwise around (0,0). Future
additions to the path are not rotated by this call.
A path is not connected to any particular dc<%> object, so
setting a dc<%> origin or scale does not affect path
operations. Instead, a dc<%>'s origin and scale apply at the
time that the path is drawn or used to set a region.