Window component order

Window component order

[John Yates]

I am embarking on allowing the mode-line to appear
at the top of a window.  To do so, one function I need
to visit is window.c's coordinates_in_window.  This is
a rather tortured bit of logic so before I go too far I
would like to validate my current understanding of
window layout.

Including a possible mode-line at top, is this the
proper top to bottom ordering of components?
(I understand, that config setting will influence
which components are actually present.)

    Top mode line
    Tab line
    Header line
    Text area
    Bottom mode line
    Horizontal scroll bar
    Bottom window divider

Similarly, is this the proper left to right ordering
of components?

    Grabbable left vertical border
    Vertical scroll bar on left
    Left fringe
    Left margin
    Text area
    Right margin
    Right fringe
    Vertical scroll bar on right
    Right window divider
    Grabbable right vertical border

/john

Re: Window component order

[Eli Zaretskii]

> From: John Yates <john@yates-sheets.org>
> Date: Mon, 9 May 2022 12:07:00 -0400
> 
> Including a possible mode-line at top, is this the
> proper top to bottom ordering of components?
> (I understand, that config setting will influence
> which components are actually present.)
> 
>     Top mode line
>     Tab line
>     Header line
>     Text area
>     Bottom mode line
>     Horizontal scroll bar
>     Bottom window divider
> 
> Similarly, is this the proper left to right ordering
> of components?
> 
>     Grabbable left vertical border
>     Vertical scroll bar on left
>     Left fringe
>     Left margin
>     Text area
>     Right margin
>     Right fringe
>     Vertical scroll bar on right
>     Right window divider
>     Grabbable right vertical border

You have the geometry in the ELisp manual, in the "Basic Windows"
node.

I think you are right, with the following 2 exceptions:

  . horizontal scroll-bar is above the mode-line, not below
  . fringes could be inside or outside the margins

Re: Window component order

[John Yates]

> You have the geometry in the ELisp manual,
> in the "Basic Windows" node.

Oops.  I knew of the Frame Geometry node.  This
window material seems less discoverable.  Did a
Window Geometry node definition get dropped
between the preceding
   -- Function: window-valid-p object
and this detailed discussion of window layout?

That said, that node has exactly the information
I sought.  Chalk up another for Emacs' awesome
documentation!

> I think you are right, with the following 2 exceptions:
>
>   . horizontal scroll-bar is above the mode-line, not below
>   . fringes could be inside or outside the margins

Exactly the feedback I was looking for.  Thank you.

/john