How to draw bigotimes and diamond with tikz?

Question

I want to draw two figures using tikz. One is bigotimes and the other one is diamond, as you can seen in the picture below. But I don't know how to draw them. Could someone help me?

Answer 1

  \documentclass[11pt]{scrartcl}
  \usepackage{tikz}
  \usetikzlibrary{shapes.geometric}
  \begin{document}
  \begin{tikzpicture} 
     \tikzset{oplus/.style={path picture={% 
        \draw[black]
         (path picture bounding box.south west) -- (path picture bounding box.north east) 
         (path picture bounding box.north west) -- (path picture bounding box.south east);
        }}} 
      \node[oplus,fill=blue!10,draw=blue,thick,circle, scale=10] {};
      \end{tikzpicture}  
   \begin{tikzpicture}
     \node [draw,scale=8,diamond,fill=orange!50]{}; 
   \end{tikzpicture}

  \end{document}    

Answer 2

here's my attempt (with limited Tikz knowledge) at the diamond in a tikzpicture environment where you set half of the largest and half of the smallest angle:

     \newcommand{\halffirstangle}{60}
      \newcommand{\halfsecondangle}{30} %half second angle = 0.5*(360-2*\halffirstangle)

        \path[draw, blue] (0,0) -- ++(\halffirstangle:1cm) -- ++(270+\halfsecondangle:1cm) -- ++(180+\halffirstangle:1cm) -- ++(90+\halfsecondangle:1cm)  ;

The shape starts from (0,0) and then relative coordinates are used. It's worth reading up on these. The subsequent pairs give the angle of the line segment first, then its length. Here the sides are 1cm in length, the angles are just worked out from basic geometry.

I can recommend the pgf-tut.pdf by Meik Hellmund if you're starting out.

Answer 3

Here is one way to draw the diamond:

\documentclass{article}
\usepackage{tikz}
\begin{document}
\tikz\node[rectangle,draw,yscale=1.2,rotate=45] {};
\end{document}

but you can't have text inside the node this way (or you can, but it gets rotated and the shape won't stay as a diamond).