Re: moving point over invisible and intangible text

[Richard Stallman]

    On a related issue, maybe line-move (and friends) could be simplified
    if one could query the display engine about "glyph-after", "glyph-before",
    "glyph-below" and "glyph-above" and let them return a buffer position
    (and possibly also an X and Y pixel position).

One complication in implementing such features is that they must
work based on the current buffer contents.  They cannot use
the records kept by the display system about the glyphs on the screen,
since those could be out of date.