+/* Parameters for rendering a table_item to a device.
+
+
+ Coordinate system
+ =================
+
+ The rendering code assumes that larger 'x' is to the right and larger 'y'
+ toward the bottom of the page.
+
+ The rendering code assumes that the table being rendered has its upper left
+ corner at (0,0) in device coordinates. This is usually not the case from
+ the driver's perspective, so the driver should expect to apply its own
+ offset to coordinates passed to callback functions.
+
+
+ Callback functions
+ ==================
+
+ For each of the callback functions, AUX is passed as the 'aux' member of the
+ render_params structure.
+
+ The device is expected to transform numerical footnote index numbers into
+ footnote markers. The existing drivers use str_format_26adic() to transform
+ index 0 to "a", index 1 to "b", and so on. The FOOTNOTE_IDX supplied to
+ each function is the footnote index number for the first footnote in the
+ cell. If a cell contains more than one footnote, then the additional
+ footnote indexes increase sequentially, e.g. the second footnote has index
+ FOOTNOTE_IDX + 1.
+*/