Pixel specification for ascent in image descriptors

Pixel specification for ascent in image descriptors

[Erik Präntare]

I am working on a package which requires overlaying some glyphs with an svg
image.  This image should appear as the original glyph, but may be taller
than one as I am rendering small indicators above them.  To appear as the
regular glyph, I need to specify the :ascent image property to be the same
as for the glyph it replaces.  However, this seems to only be possible to
do as a fraction of the image height (expressed as an integer percentage).
This seems to sometimes cause small jitters from off-by-one pixel errors.

Is it possible to specify the ascent of the image in the amount of pixels
instead, similar to how one can with pixel specifications for spaces?

Re: Pixel specification for ascent in image descriptors

[Michael Heerdegen via Users list for the GNU Emacs text editor]

Erik Präntare <erik.prantare@gmail.com> writes:

> Is it possible to specify the ascent of the image in the amount of pixels
> instead, similar to how one can with pixel specifications for spaces?

The manual tells it is.


Michael.

Re: Pixel specification for ascent in image descriptors

[Michael Heerdegen]

Michael Heerdegen via Users list for the GNU Emacs text editor
<help-gnu-emacs@gnu.org> writes:

> > Is it possible to specify the ascent of the image in the amount of pixels
> > instead, similar to how one can with pixel specifications for spaces?
>
> The manual tells it is.

In the meantime I found out that I had been looking for the :ascent
property for the specification of spaces.  Sorry for that.

After reading the correct parts of the manual it indeed seems the answer
is just "no".

If anybody is able to be more helpful than I was that would be nice.


Michael.