Re: `-bg Transparent` option isn't ignored when background color is set in dvi file

[Jan-Åke Larsson]

Hi,

That was intended, yes, the manual should probably have said "The background color given will be ignored if there is a background color \special in the DVI."

"Transparent" doesn't change the background color, it enables the alpha channel.

The actual background color (visible, say, in a reader without the alpha channel) is controlled by the color spec, and overridden by a color \special.

Did you want this to work differently, or was the problem that you were surprised by the behavior?

Best
Jan-Åke

On mån, 2021-05-17 at 17:41 +0000, Sébastien Miquel wrote:

Hi,

The manual says that the `-bg` option is ignored if a background color

is set in the DVI, however this doesn't seem to be the case if `-bg

Transparent` is used.

To reproduce, I used a tex file with the following content.

#+BEGIN_SRC latex

\documentclass{article}

\usepackage{xcolor}

\title{Text}

\begin{document}

\maketitle

\definecolor{bg}{rgb}{0.858, 0.188, 0.478} % magenta

\pagecolor{bg}

\end{document}

#+END_SRC

Then compile it using

#+BEGIN_SRC bash

latex -interaction nonstopmode test_latex_bg.tex

dvipng -bg Transparent -o test.png test_latex_bg.dvi

#+END_SRC

The resulting png is Transparent instead of magenta. If I specify `-bg

Blue` instead, the background is set to magenta, as expected.

Is this behaviour intended ?

Regards,

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