Re: Display-relative coordinates

[martin rudalics]

> It would still be useful, I think, to have a function that returns
> directly the screen-relative pixel coordinates (i.e., even though
> that can be got using `window-absolute-pixel-position' and
> `frame-geometry'.)

‘window-absolute-pixel-position’ does that already.  Quoting the Elisp
manual:


 -- Function: window-absolute-pixel-position &optional position window
     If the buffer position POSITION is visible in window WINDOW, this
     function returns the display coordinates of the upper/left corner
     of the glyph at POSITION.  The return value is a cons of the X-
     and Y-coordinates of that corner, relative to an origin at (0, 0)
     of WINDOW's display.  It returns `nil' if POSITION is not visible
     in WINDOW.

     WINDOW must be a live window and defaults to the selected window.
     POSITION defaults to the value of `window-point' of WINDOW.

     This means that in order to move the mouse pointer to the position
     of point in the selected window, it's sufficient to write:

          (let ((position (window-absolute-pixel-position)))
            (set-mouse-absolute-pixel-position
             (car position) (cdr position)))


Note the example given at the end.  ‘set-mouse-absolute-pixel-position’
warps the mouse pointer on your screen without any knowledge of the
existence or position of frames/windows on that screen.  You can use
that function as an acid test for your own favorite function's ability
to retrieve precise screen coordiantes.

martin