cairo:source (cr)

cr -- a cairo:context-t instance
source -- a cairo:pattern-t instance to be used as the source for subsequent drawing operations

Gets or sets the source pattern for cr. The source pattern is owned by Cairo. To keep a reference to it, you must call the cairo:pattern-reference function.

The source pattern will be used for any subsequent drawing operation until a new source pattern is set. The default source pattern is a solid pattern that is opaque black, that is, it is equivalent to

(cairo:set-source-rgb cr 0.0 0.0 0.0)  

The current transformation matrix (CTM) of the pattern will be locked to the user space in effect at the time of the call of the (setf cairo:source) function. This means that further modifications of the CTM will not affect the source pattern. See the cairo:pattern-matrix function.