Re: [bug] latex fragment preview with dvipng ignores :foreground specification

[Nick Dokos <nicholas.dokos@hp.com>]

Eric S Fraga <e.fraga@ucl.ac.uk> wrote:

> Hello,
> 
> I am trying to use org-tree-slide for an interactive session I have to
> facilitate soon.  This works quite well, in a geeky kind of way ;-)
> 
> However, I do want to display a couple of equations and using latex
> fragments is the most appealing mechanism.  When I try to use
> org-preview-latex-fragment, the latex image is
> generated.  Unfortunately, as I use a black background on my display, I
> cannot see the fragment as it is being generated with black text on a
> transparent background by default.  Note, I am using dvipng for the
> image conversion.
> 
> I can customise org-format-latex-options to fix this, or so I
> thought.  No matter what I do, the resulting latex fragment has black
> text.  The problem appears to be that the -fg option to dvipng does not
> work so it doesn't matter how I customise org-format-latex-options.
> 

I think that's true. Using dvipng from the command line, I can change
the background but not the foreground.

> Can anybody suggest a workaround (without changing the actual latex
> itself)?  I can customise the above variable to set the background for
> latex images to white, which at least allows the equations to be seen,
> but this is a mildly ugly solution.  :( And ruins any geek street cred I
> might have had ;-)
> 

Use a light background emacs for the presentation. And don't tell
anybody that you switched. Street creds intact, you can switch back to
the cool dark background afterwards. If you get caught, you can argue
that you switched for projection purposes (assuming that you are going
to use a projector): studies show that dark letters on a light
background are easier to see from a distance (citation: J.WhlClthFab,
Vol. 3.14159, p. 2.7182818, Apr. 1, 1999)

Nick