Problem giving color to a logo

Question

I'm writing a manual for a class, and I never liked add images as files in my tex, so I'm drawning the logo with this code:

\documentclass{article}
\usepackage{tikz}
\begin{document}
\definecolor{xdxdff}{rgb}{0.5,0.5,1.}
\definecolor{qqqqff}{rgb}{0.,0.,1.}
\definecolor{cqcqcq}{rgb}{0.75,0.75,0.75}
\begin{tikzpicture}
\clip(-4.42,-1.90) rectangle (8.03,4.69);
\draw [color=red,fill=red,fill opacity=1.0] (-0.67,1.06) circle (2.41cm);
\draw [color=white,fill=white,fill opacity=1.0] (-0.66,1.71) circle (1.92cm);
\draw [shift={(-0.05,2.21)},color=red]  plot[domain=2.01:4.03,variable=\t]({1.*1.40*cos(\t r)+0.*1.40*sin(\t r)},{0.*1.40*cos(\t r)+1.*1.40*sin(\t r)});
\draw [shift={(-1.60,0.27)},color=red]  plot[domain=-0.48:0.92,variable=\t]({1.*1.08*cos(\t r)+0.*1.08*sin(\t r)},{0.*1.08*cos(\t r)+1.*1.08*sin(\t r)});
\draw [shift={(-1.26,1.06)},color=red]  plot[domain=-1.12:0.68,variable=\t]({1.*1.43*cos(\t r)+0.*1.43*sin(\t r)},{0.*1.43*cos(\t r)+1.*1.43*sin(\t r)});
\draw [shift={(0.42,3.0)},color=red] plot[domain=2.72:4.22,variable=\t]({1.*1.18*cos(\t r)+0.*1.18*sin(\t r)},{0.*1.18*cos(\t r)+1.*1.18*sin(\t r)});
\end{tikzpicture}
\end{document}

which gives me this image

How can I color red the thing in middle?

Answer 1

I think the part in the middle is easier to draw using the curve to construction than .. controls ... At least, for me, though I have only recently started to have any clue about the latter so it might just be my lack of experience.

Anyway, this is very close although it is not an absolutely perfect match. (But the faint red line tracing the top of the circle is a viewer artefact, I think, and not an imperfection in construction. But the bit in the middle is not an entirely perfect match.)

\documentclass[tikz,border=5pt,multi]{standalone}
\usetikzlibrary{calc}
\begin{document}
\begin{tikzpicture}
  \clip (-.67,1.06) circle (24.1mm);
  \path [fill=red, even odd rule] (-.67,1.06) coordinate (c1) circle (24.1mm) ++(.01,.65) coordinate (c2) circle (19.2mm);
  \draw [draw=red, fill=red] (c2) +(.05,-19.2mm) [out=25, in=-45] to (-.15,1.95) [out=150, in=-125] to ($(c1) + (.05,24.1mm)$) coordinate (a) [out=-155, in=90] to (-1.45,2.2) [out=-90, in=135] to ++(.51,-1.05) [out=-45, in=70] to cycle;
\end{tikzpicture}
\end{document}

EDIT

Simply changing the sixth line as suggested in Luis Felipe's comment to

  \path [fill=red, even odd rule] (-.67,1.08) coordinate (c1) circle (24.1mm) ++(.01,.65) coordinate (c2) circle (19.2mm);

eliminates the faint trace of red line but at the cost of cutting off the tip of the inner part of the logo:

However, if we set the coordinate used for the inner part before making the adjustment, perhaps we can get the best of both worlds:

  \path [fill=red, even odd rule] (-.67,1.06) coordinate (c1) ++(0,0.02) circle (24.1mm) ++(.01,.65) coordinate (c2) circle (19.2mm);

\documentclass[tikz,border=5pt,multi]{standalone}
\usetikzlibrary{calc}
\begin{document}
\begin{tikzpicture}
  \clip (-.67,1.06) circle (24.1mm);
  % tweak based on Luis Felipe's comment: ref: https://tex.stackexchange.com/questions/286335/problem-giving-color-to-a-logo/286392?noredirect=1#comment692032_286392
  \path [fill=red, even odd rule] (-.67,1.06) coordinate (c1) ++(0,0.02) circle (24.1mm) ++(.01,.65) coordinate (c2) circle (19.2mm);
  \draw [draw=red, fill=red] (c2) +(.05,-19.2mm) [out=25, in=-45] to (-.15,1.95) [out=150, in=-125] to ($(c1) + (.05,24.1mm)$) coordinate (a) [out=-155, in=90] to (-1.45,2.2) [out=-90, in=135] to ++(.51,-1.05) [out=-45, in=70] to cycle;
\end{tikzpicture}
\end{document}

Answer 2

Here is a simple solution. You may adjust the parameters (\anglei, \angleii, \angleiii, and \len) to change the flame.

\documentclass[tikz]{standalone}
\begin{document}
\begin{tikzpicture}[line width=0,draw=blue]
  \fill[red] (0,0) circle (2.41);
  \begin{scope}[overlay]
    \fill[white] (0,.65) circle (1.92);
  \end{scope}
  \def\anglei{-65}
  \def\angleii{45}
  \def\angleiii{160}
  \def\len{1.5}
  \fill[red]
  (0,.65) ++(0,-1.92)
  arc[start angle=\anglei,end angle=\angleii,radius=\len]
  arc[start angle=\angleii+180,end angle=\angleiii,radius=\len]
  %
  arc[start angle=\anglei+180,end angle=\angleii+180,radius=\len]
  arc[start angle=\angleii+360,end angle=\angleiii+180,radius=\len]
  ;
\end{tikzpicture}
\end{document}

Answer 3

run with xelatex. The origin is the center of the big circle. \pscustom builds a closed path which can be filled.

\documentclass[pstricks]{standalone}
\usepackage{pstricks}
\begin{document}

\begin{pspicture}(-3,-3)(3,3)
\pscircle*[linecolor=red]{2.41}
\pscircle*[linecolor=white](0,0.65){1.92}
\pscustom[fillstyle=solid,fillcolor=red,linecolor=red]{%
  \psarc(0.65,1.15){1.4}{!2.01 RadtoDeg}{!4.0 RadtoDeg}
  \psarcn(-0.91,-0.79){1.08}{!0.93 RadtoDeg}{!-0.48 RadtoDeg}
  \psarc(-0.58,0){1.43}{!-1.12 RadtoDeg}{!0.68 RadtoDeg}
  \psarcn(1.1,1.94){1.18}{!4.2 RadtoDeg}{!2.72 RadtoDeg}
}
\end{pspicture}

\end{document}

If you want to use pdflatex:

\documentclass{book}
\usepackage{pstricks}
\usepackage{auto-pst-pdf}
\begin{document}
[...] 

and run pdflatex --shell-escape file.tex

Answer 4

Not quite right, but anyway...

\documentclass[tikz,border=5]{standalone}
\begin{document}
\tikz[line join=round]\filldraw [red] (0,0) 
  arc (270:180-30:cos 45 / cos 30) arc (180-45:360+45:1)
  arc (30:-90:cos 45 / cos 30) -- cycle
  .. controls ++(30:1) and ++(210:3/2) .. (0,1.5)
  .. controls ++(210:1) and ++(30:3/2) .. cycle;
\end{document}