Drawing a sphere and an ellipsoid in the same picture in TiKz

Question

I'm working on a project an I want to put a picture like this

using TikZ but instead a fat arrow, I want to draw a curve arrow, that illustrates the fact that a function f sends the sphere into an ellipsoid.

Can someone help me about how to do this? Thanks in advance.

Answer 1

You can use two example images named A and B. \tikzset give you the type of the arrow with the options of your size and position. The idea is taken from this link Fancy arrows with TikZ using the best code of the user @Peter Grill that I have modificated appropriately.

\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{shapes}
\usepackage{graphicx}
\usepackage{xcolor}
\tikzset{My Arrow Style/.style={single arrow, rounded corners=1pt, fill=lightgray, anchor=center, align=center,xshift=2cm, yshift=2cm, minimum height=2cm, minimum width=2cm,text width=4cm}}
\newcommand{\MyArrow}[2][]{\tikz[baseline={([yshift=-7ex]current bounding box.center)}] \node [My Arrow Style,#1] {#2};}
\begin{document}
\begin{figure}
  \includegraphics[width=3cm,height=5cm,keepaspectratio]{example-image-a}
  \MyArrow{Affine trasformation}
  \includegraphics[width=3cm,height=5cm,keepaspectratio]{example-image-b}
\end{figure}
\end{document}