Specifies the callbacks used to generate the image surface for a rendering
operation (acquire) and the function used to cleanup that surface afterwards.
The acquire callback should create a surface (preferably an image
surface created to match the target using
Surface.createSimilarImage) that defines at least the region
of interest specified by extents. The surface is allowed to be the entire
sample area, but if it does contain a subsection of the sample area,
the surface extents should be provided by setting the device offset (along
with its width and height) using Surface.setDeviceOffset.
Since 1.12
Specifies the callbacks used to generate the image surface for a rendering operation (acquire) and the function used to cleanup that surface afterwards. The acquire callback should create a surface (preferably an image surface created to match the target using Surface.createSimilarImage) that defines at least the region of interest specified by extents. The surface is allowed to be the entire sample area, but if it does contain a subsection of the sample area, the surface extents should be provided by setting the device offset (along with its width and height) using Surface.setDeviceOffset. Since 1.12