Cfrgtkky

I am writing a template for a poster (using beamer/beamerposter) package for students that I intend to distribute as a folder. It will contain a .tex file that the students can start editing, and a style file, which is a custom beamer theme, that I do not want them to mess with.

The theme is already designed to look nice with one user-specified color, with all other structure and text colors derived from that color using colorlet{usercolor!10!white} etc. type of mixins.

The thing works as defined above.

The work is nearly done, except for one vexing issue. I want the students to be able to define the user-specified color in the .tex file and not have to ever edit the style file.

So, I tried the following:

beamerthemeXXX.sty:

...

newcommand{postercolor}[3]{def@posterR{#1}def@posterG{#2}def@posterB{#3}}

definecolor{posterthemecolor}{RGB}{@posterR,@posterG,@posterB}

...

I have the following directive in .tex file:

postercolor{128}{0}{0}

I get a lot undefined control sequence errors in the style file where I am using @posterX macros.

I guess that this question is more TeX and less color related. How do I force the def's in the newcommand definition above to expand immediately?

I apologize for not providing an MWE as there are several files involved, some containing confidential information. In any case, I have a hunch that this problem is largely due to my programming brain failing to come to terms with some TeX peculiarities.

You don't have to use the def@poster* macros at all. Just define the colour inside postercolor and ensure that it's initialised by your style.

documentclass{article}



%usepackage{beamerthemeXXX}



% contents of beamerthemeXXX.sty

usepackage{xcolor}

% ...

% define theme colour setting macro

newcommand{postercolor}[3]{definecolor{posterthemecolor}{RGB}{#1,#2,#3}}



% initialise theme colour

postercolor{128}{0}{0}

% ...

% end of beamerthemeXXX.sty



% user document preamble



% redefine theme colour if necessary

postercolor{0}{128}{0}



begin{document}



textcolor{posterthemecolor}{poster colour}



end{document}