Re: cursor doesn't show through transparent images in emacs 22, unlike emacs 21

["Ken Manheimer" <ken.manheimer@gmail.com>]

On 8/24/06, Kim F. Storm <storm@cua.dk> wrote:
> "Ken Manheimer" <ken.manheimer@gmail.com> writes:
>
> > as i think i suggested in a previous message, the solution i would
> > prefer would be to have some way to qualify icons so that they get a
> > solid cursor in their transparent areas, and the default would be to
> > have it inactive.  eg, a qualifier for xpm, png, gif, and other
> > transparent-capable images, like :solid-cursor:
> >
> > `:solid-cursor-shows BOOLEAN'
> >       When true, the cursor will appear solid through the transparent
> > regions of the image
> >       when the cursor is situated on the image and the window is
> > active.  The default is for
> >       only the cursor border to show, whether or not the window is active.
> >
> > by having the default be off, then the disruption of oversize blinking
> > icons will be avoided.
>
> Below is a patch which adds a new image :cursor property where you can
> specify the actual type of cursor to show on the image in the selected
> window (that is more flexible than your suggestion, and just as easy
> to do).

yay!

> Due to limitations in what cursors can be displayed for an image (bar
> and hbar both gives a solid box??), it only works to set it to
> box, hollow, and t (which means use whatever cursor-type is in the
> buffer).
>
>
> As an additional part of the patch, it only changes the cursor
> from box to hollow for images which as greater than 4 times the
> frame's default font size i.e. small images will behave like
> normal glyphs with respect to the box cursor.
>
> We can use either or both methods -- WDYT ?

if i'm understanding correctly, i think either or both methods will
satisfy my needs - thanks!

i'm not clear how the two interact - will the :cursor setting only
affect glyphs larger than 4 times the frame's default font size?  or
does it mean that glyphs will have particular cursors if they either
are 4 times the size or if they have an explicit :cursor display
setting?  my concern is settled either way, but the documentation may
be complex if there's no simple answer.

i also wonder whether it will be confusing to have the option for
graphics formats that don't support transparency, but have no strong
opinions about this.

i agree w/david about making the scaling threshold a parameter.  that
could actually help with documentation by providing an artifact that's
conveys some of the explanation.  i would lean towards a scaling
factor rather than absolute pixels/points, but haven't thought that
through.

by the way, i (eagerly) applied your patch by hand, but am unable to
compile - i'm getting complaints about QCursor being undeclared:

xdisp.c: In function `get_window_cursor_type':
xdisp.c:21219: error: `QCcursor' undeclared (first use in this function)
xdisp.c:21219: error: (Each undeclared identifier is reported only once
xdisp.c:21219: error: for each function it appears in.)
xdisp.c: In function `syms_of_xdisp':
xdisp.c:23733: error: `QCcursor' undeclared (first use in this function)

did i miss something, or is there more to the patch?

ken

> *** xdisp.c     22 Aug 2006 23:28:12 +0200      1.1113
> --- xdisp.c     24 Aug 2006 13:12:33 +0200
> ***************
> *** 367,373 ****
>   Lisp_Object Qimage;
> [...]

-- 
ken
ken.manheimer@gmail.com
http://myriadicity.net