Sets the given window as the source pattern for cr.
The pattern has an extend mode of cairo_extend_none and is aligned so that the origin of window
is x, y. The window contains all its subwindows when rendering.
Note that the contents of window are undefined outside of the visible part of window, so use this function with
care.
| cr |
a cairo context |
| window |
a Window |
| x |
X coordinate of location to place upper left corner of |
| y |
Y coordinate of location to place upper left corner of |