+#endif /* HAVE_WINDOW_SYSTEM */
+
+ /* Mapping of coordinate pairs to buffer positions.
+ This field holds a vector indexed by row number.
+ Its elements are vectors indexed by column number.
+ Each element of these vectors is a buffer position, 0, or -1.
+
+ For a column where the image of a text character starts,
+ the element value is the buffer position of that character.
+ When a window's screen line starts in mid character,
+ the element for the line's first column (at the window's left margin)
+ is that character's position.
+ For successive columns within a multicolumn character,
+ the element is -1.
+ For the column just beyond the last glyph on a line,
+ the element is the buffer position of the end of the line.
+ For following columns within the same window, the element is 0.
+ For rows past the end of the accessible buffer text,
+ the window's first column has ZV and other columns have 0.
+
+ Mode lines and vertical separator lines have 0.
+
+ The column of a window's left margin
+ always has a positive value (a buffer position), not 0 or -1,
+ for each line in that window's interior. */
+
+ int **charstarts;
+
+ /* This holds all the space in the subvectors of the charstarts field. */
+ int *total_charstarts;