How can I make a filled and how an unfilled circle in TikZ with multiple color transitions? I need about five distinct colors which shall be defined at specific angles and the blur area / transition area should be rather small. In other words, there should be larger areas of a single color and then a rather a small (angle) area in which the colors blur/transition into each other.
Filled circle would look something like this (but with smaller transition areas):
An unfilled circle would look like this (but with smaller transition areas):
I am guessing that shade or shadedraw are my friends, but I am still kind of lost.
First try...
\documentclass[tikz,border=5]{standalone}
\usepgflibrary{shadings}
\begin{document}
\begin{tikzpicture}[scale=3]
\shade[shading=color wheel] [even odd rule] (0,0) circle (1.5) (0,0) circle (1);
\shade[shading=color wheel white center] (0,5) circle (1.5);
\end{tikzpicture}
\end{document}
but
- I am not sure how to change the number of colours,
- nor the transition area,
- nor a way to set the angle for the colours.
Second try...
In How to create a color wheel shading with other colors? there is code that allows to change the colours and the number of colours. I guess I could make the transition area smaller by adding a colour multiple times, like
\documentclass[tikz,border=5]{standalone}
% \usetikzlibrary{shapes,arrows,chains,positioning,calc,trees,mindmap,backgrounds,shadows,decorations.text}
\usetikzlibrary{decorations.text}
\makeatletter
\newtoks\pgf@ps@toks
\newcount\c@pgf@ps
\def\pgf@ps@sp{ }
\def\pgf@ps@esettoks#1{\edef\pgf@ps@tmp{#1}\pgf@ps@toks\expandafter{\pgf@ps@tmp}}
\def\pgf@ps@repop#1#2{%
\c@pgf@countb=#2\relax%
\def\pgf@ps@op{#1}%
\def\pgf@ps@ops{}\pgf@ps@@repop}
\def\pgf@ps@@repop{%
\ifnum\c@pgf@countb<1\relax%
\else%
\edef\pgf@ps@ops{\pgf@ps@op\pgf@ps@ops}%
\advance\c@pgf@countb by-1\relax%
\expandafter\pgf@ps@@repop%
\fi%
}
\def\pgf@ps@generate@ps{%
\c@pgf@counta=\pgf@ps@ncol\relax%
\c@pgf@countb=\c@pgf@counta%
\advance\c@pgf@countb by-1\relax%
\pgf@ps@esettoks{ \noexpand\pgf@ps@interp{col@\the\c@pgf@counta}{col@\the\c@pgf@countb} }%
\pgfmathloop
\ifnum\c@pgf@counta<2\relax%
\else%
\c@pgf@countb=-\c@pgf@counta%
\advance\c@pgf@countb by\pgf@ps@ncol\relax%
\advance\c@pgf@counta by-1\relax%
\pgf@ps@repop{pop\pgf@ps@sp}{\c@pgf@countb}%
\c@pgf@countb=\c@pgf@counta%
\advance\c@pgf@countb by-1\relax%
\ifnum\c@pgf@countb=0\relax%
\c@pgf@countb=\pgf@ps@ncol\relax%
\fi%
\pgf@ps@esettoks{ \the\c@pgf@counta\pgf@ps@sp eq { \pgf@ps@ops \noexpand\pgf@ps@interp{col@\the\c@pgf@counta}{col@\the\c@pgf@countb} }{ \the\pgf@ps@toks } ifelse}%
\repeatpgfmathloop%
\c@pgf@counta=\pgf@ps@ncol\relax%
\advance\c@pgf@counta by-2\relax%
\pgf@ps@repop{dup\pgf@ps@sp}{\c@pgf@counta}%
\pgf@ps@esettoks{ \pgf@ps@ops \the\pgf@ps@toks }%
}
\def\pgf@ps@colorstorgb#1{%
\c@pgf@ps=1\relax%
\pgfutil@for\pgf@ps@:={#1}\do{%
\pgf@ps@coltorgb{\pgf@ps@}{col@\the\c@pgf@ps}%
\advance\c@pgf@ps by1\relax}%
}
\def\pgf@ps@coltorgb#1#2{%
\edef\pgf@ps@marshal{\noexpand\pgfshadecolortorgb{#1}}%
\expandafter\pgf@ps@marshal\expandafter{\csname#2\endcsname}%
}
\def\pgf@ps@rgb#1{\csname#1\endcsname}
\def\pgf@ps@interp#1#2{%
\pgf@ps@rgb{#1red} mul exch \pgf@ps@rgb{#2red} mul add
5 1 roll
\pgf@ps@rgb{#1green} mul exch \pgf@ps@rgb{#2green} mul add
3 1 roll
\pgf@ps@rgb{#1blue} mul exch \pgf@ps@rgb{#2blue} mul add
}
\def\pgfdeclarecolorwheelshading#1#2#3{%
\pgf@ps@getcols{#3}%
\pgfmathparse{mod(#2+360/\pgf@ps@ncol-90,360)}%
\pgf@x=\pgfmathresult pt\relax%
\ifdim\pgf@x<0pt\relax%
\advance\pgf@x by360pt\relax%
\fi%
\edef\pgf@ps@rot{\pgfmath@tonumber{\pgf@x}}%
\pgf@ps@generate@ps%
\pgf@ps@esettoks{%
\noexpand\pgfdeclarefunctionalshading[#3]{#1}%
{\noexpand\pgfpoint{-50bp}{-50bp}}{\noexpand\pgfpoint{50bp}{50bp}}%
{\noexpand\pgf@ps@colorstorgb{#3}}%
{%
2 copy abs exch abs add 0.0001 ge { atan } { pop } ifelse
\pgf@ps@rot\pgf@ps@sp add dup 360 ge { -360 add } { } ifelse
360 \pgf@ps@ncol\pgf@ps@sp
div div dup floor dup 3 1 roll neg add dup neg 1 add exch
2 copy 2 copy 7 -1 roll 1 add
\the\pgf@ps@toks}}%
\edef\pgf@ps@marshal{\the\pgf@ps@toks}%
\pgf@ps@marshal}
\def\pgf@ps@getcols#1{%
\c@pgf@ps=0\relax%
\pgfutil@for\pgf@ps@:={#1}\do{\advance\c@pgf@ps by1}%
\edef\pgf@ps@ncol{\the\c@pgf@ps}%
}
\pgfdeclarecolorwheelshading{rgb}{0}{red,green,blue}
\pgfdeclarecolorwheelshading{rgb-90}{90}{red,green,blue}
\pgfdeclarecolorwheelshading{mywheel}{90}{red,red,red!80!green,red!20!green,green,green,green!80!blue,green!20!blue,blue,blue,blue!80!yellow,blue!20!yellow,yellow,yellow,yellow!80!red,yellow!20!red}
\pgfdeclarecolorwheelshading{rainbow}{-45}{red,yellow,pink,green,orange,purple,blue}
\begin{document}
\begin{tikzpicture}
\path [shading=mywheel] (0,0) circle [radius=10];
\path[fill=white] (0,0) circle[radius=9];
\draw[-latex,
postaction={decorate},
decoration={
text along path,
text={|\LARGE|Data Science},
text align=center,
text color=black,
% every character/.style={fill=white, yshift=-0.5ex},
raise=-9mm
},
draw=none]
(180:10) arc [start angle=180,end angle=200,radius=10]; % Grad 190
\draw[-latex,
postaction={decorate},
decoration={
text along path,
text={|\LARGE|Mathematical Modelling},
text align=center,
text color=black,
% every character/.style={fill=white, yshift=-0.5ex},
raise=-9mm
},
draw=none]
(200:10) arc [start angle=200,end angle=260,radius=10]; % Grad 230
\draw[-latex,
postaction={decorate},
decoration={
text along path,
text={|\LARGE|Big Data},
text align=center,
text color=black,
raise=3mm
},
draw=none]
(100:10) arc [start angle=100,end angle=80,radius=10]; % Grad 90
\draw[-latex,
postaction={decorate},
decoration={
text along path,
text={|\LARGE|Industry 4.0},
text align=center,
text color=black,
% every character/.style={fill=white, yshift=-0.5ex},
raise=-9mm
},
draw=none]
(320:10) arc [start angle=320,end angle=340,radius=10]; % Grad 330
\path (0,15) (0,-15) (15,0) (-15,0);
\end{tikzpicture}
\end{document}
with
But how can the code be altered so that I can set the angles for the colours?
In this case namely at 90, 190, 230, and 330 degree.
