This namespace lists utility functions attached to an instance of
Rac during initialization. Each drawable and style class gets
a corresponding function like rac.Point or
rac.Color.
Drawable and style objects require for construction a reference to a
rac instance in order to perform drawing operations. The attached
functions build new objects using the calling Rac instance.
These functions are also setup with ready-made convenience objects for
many usual values like rac.Angle.north or
rac.Point.zero.
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