Put one symbol into another

Question

I'm curious how I can make a custom character, more specificlly I want to inscribe equal sign into different shapes like circle, trianle and whatever I want. Is it possible to do that without tikz package?

Here is an example of what I want (I made it using image editor just to show).

Answer 1

Here's a solution, or at least a partial one. It defines an \inscribedeq command, which takes as a mandatory argument the symbol in which the equal sign should be inscribed. It also takes two optional arguments which allow to fine-tune the look of the result:

• The first optional argument is a length by which the symbol is raised;
• The second one is a factor by which the symbol is scaled.

Here are a few examples with symbols from MnSymbol.

\documentclass{article}
\usepackage{amsmath}
\usepackage{MnSymbol}
\usepackage{graphicx}
\usepackage{xparse}

\newlength{\eqwidth}
\newlength{\symbwidth}
\newlength{\maxwidth}
\settowidth{\eqwidth}{\(=\)}
\NewDocumentCommand{\inscribedeq}{O{0pt} O{1} m}{%
    \settowidth{\symbwidth}{\scalebox{#2}{\(#3\)}}
    \ifdim \eqwidth > \symbwidth
        \let\maxwidth\eqwidth
    \else
        \let\maxwidth\symbwidth
    \fi%
    \mathrel{%
        \raisebox{#1}{\makebox[0pt][l]{\scalebox{#2}{\(#3\)}}}%
        \makebox[\maxwidth]{\(=\)}%
    }%
}
\begin{document}
\begin{tabular}{ll}
\( x \inscribedeq{} y \)                & \( x \inscribedeq{\largecircle} y \)                  \\
\( x \inscribedeq{\largesquare} y \)    & \( x \inscribedeq[.1pt][1.1]{\largetriangleup} y \)   \\
\( x \inscribedeq{\largediamond} y \)   & \( x \inscribedeq{\circlearrowleft} y \)              \\
\( x \inscribedeq{\bigcup} y \)         & \( x \inscribedeq[-1pt][1.5]{\largestar} y \)
\end{tabular}
\end{document}