39.13.5 Customizing Fringe Bitmaps

function define-fringe-bitmap bitmap bits \&optional height width align

This function defines the symbol bitmap as a new fringe bitmap, or replaces an existing bitmap with that name.

The argument bits specifies the image to use. It should be either a string or a vector of integers, where each element (an integer) corresponds to one row of the bitmap. Each bit of an integer corresponds to one pixel of the bitmap, where the low bit corresponds to the rightmost pixel of the bitmap. (Note that this order of bits is opposite of the order in XBM images; see XBM Images.)

The height is normally the length of bits. However, you can specify a different height with non-nil height. The width is normally 8, but you can specify a different width with non-nil width. The width must be an integer between 1 and 16.

The argument align specifies the positioning of the bitmap relative to the range of rows where it is used; the default is to center the bitmap. The allowed values are top, center, or bottom.

The align argument may also be a list (align periodic) where align is interpreted as described above. If periodic is non-nil, it specifies that the rows in bits should be repeated enough times to reach the specified height.

function destroy-fringe-bitmap bitmap

This function destroys the fringe bitmap identified by bitmap. If bitmap identifies a standard fringe bitmap, it actually restores the standard definition of that bitmap, instead of eliminating it entirely.

function set-fringe-bitmap-face bitmap \&optional face

This sets the face for the fringe bitmap bitmap to face. If face is nil, it selects the fringe face. The bitmap’s face controls the color to draw it in.

face is merged with the fringe face, so normally face should specify only the foreground color.