Btukfyl

1. Sharing float (fig) and thm counter can be done with newtheorem{theorem}[figure]{Theorem}.


2. Correctly ordering float (fig) counter based on actual location in the PDF (as opposed to location in source code) can be done with MakeSorted{figure} from perpage.sty.


3. Sharing float (fig) and eqn counter can be done with makeatletterletc@equationc@figuremakeatother.

I can do 1 and 2 together (see mwe-b).
I can do 1 and 3 together (see mwe-c).
But I can't do all three together (see mwe-d).

Partial/fake solution. I can skirt the issue by making a myeqn environment (see mwe-a).

Question. Is there an actual solution that allows you to keep the equation environment? Maybe one can resolve the clash in mwe-d by swapping c@figure out for something (based on the precise implementation of perpage.sty)? Any help would be greatly appreciated!

%% MWE-A

documentlass{article}

usepackage{blindtext}

newtheorem{theorem}[figure]{Theorem} %1

usepackage{perpage}MakeSorted{figure} %2

newenvironment{myeqn}

  {stepcounter{figure}hfillbegin{math}}

  {end{math}hfill(arabic{figure})}

begin{document}

begin{theorem}blindtextend{theorem}

begin{figure}blindtextcaption{Caption}end{figure}

begin{myeqn}a^2+b^2=c^2end{myeqn}

end{document}



%% MWE-B

documentclass{article}

usepackage{blindtext}

newtheorem{theorem}[figure]{Theorem} %1

usepackage{perpage}MakeSorted{figure} %2

begin{document}

begin{theorem}blindtextend{theorem}

begin{figure}blindtextcaption{Caption}end{figure}

begin{equation}a^2+b^2=c^2end{equation}

end{document}



%% MWE-C

documentclass{article}

usepackage{blindtext}

newtheorem{theorem}[figure]{Theorem} %1

makeatletterletc@equationc@figuremakeatother %3

begin{document}

begin{theorem}blindtextend{theorem}

begin{figure}blindtextcaption{Caption}end{figure}

begin{equation}a^2+b^2=c^2end{equation}

end{document}



%% MWE-D

documentclass{article}

usepackage{blindtext}

newtheorem{theorem}[figure]{Theorem} %1

usepackage{perpage}MakeSorted{figure} %2

makeatletterletc@equationc@figuremakeatother %3

begin{document}

begin{theorem}blindtextend{theorem}

begin{figure}blindtextcaption{Caption}end{figure}

begin{equation}a^2+b^2=c^2end{equation}

end{document}