[Tex/LaTex] Regular Polygon with tip on the bottom

rotatingtikz-pgf

I have a set of three regular polygons with six sides which I create using regular polygon from the shapes tikz package. However this always creates the polygon with the flat side on the bottom. How do I get one of the corners on the bottom with minimal changes to my code:

\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{shapes}
\begin{document}
\begin{tikzpicture}
\def\x{0}
\def\y{0}
\def\r{1.5}
\pgfmathsetmacro\dx{\r*(1+cos(60))}
\pgfmathsetmacro\dy{\r*sin(60)}
\pgfmathsetmacro\dAx{\r*cos(60)}
\pgfmathsetmacro\dAy{\r*sin(60)}
\pgfmathsetmacro\dBx{\r*cos(120)}
\pgfmathsetmacro\dBy{\r*sin(120)}
\pgfmathsetmacro\d{2*\r}

\def\xc{\x} %mittelpunkt des aktuellen hexagons
\def\yc{\y}
\node[draw, regular polygon, regular polygon sides=6,minimum size=\d cm]
at (\x,\y) {};
\node[circle, radius=0.15cm, label=A, fill=black] (A) at (\xc+\dAx,    
\yc+\dAy) {};
\node[circle, radius=0.15cm, label=below:A, fill=black] (AA) at     
(\xc+\dAx,\yc-\dAy) {};
\node[circle, radius=0.15cm, label=A, fill=black] at (\xc-\r,\yc) {};
\node[circle, radius=0.15cm, label=B, fill=gray] at (\xc+\dBx,\yc+\dBy) {};
\node[circle, radius=0.15cm, label=below:B, fill=gray] at (\xc+\dBx,    \yc-\dBy) {};

\def\xc{\x+\dx}
\def\yc{\y+\dy}
\node[draw, regular polygon, regular polygon sides=6,minimum size=\d cm]
at (\x+\dx,\y+\dy) {};
\node[circle, radius=0.15cm, label=A, fill=black] (AAA) at (\xc+\dAx,\yc+\dAy) {};
\node[circle, radius=0.15cm, label=right:A, fill=black] (AAAA) at (\xc+\dAx,\yc-\dAy) {};
\node[circle, radius=0.15cm, label=right:B, fill=gray] (BB) at (\xc+\r,\yc) {};
\node[circle, radius=0.15cm, label=B, fill=gray] at (\xc+\dBx,\yc+\dBy) {};

\def\xc{\x+\dx}
\def\yc{\y-\dy}
\node[draw, regular polygon, regular polygon sides=6,minimum size=\d cm]
at (\x+\dx,\y-\dy) {};
\node[circle, radius=0.15cm, label=below:A, fill=black] at (\xc+\dAx,\yc-\dAy) {};
\node[circle, radius=0.15cm, label=right:B, fill=gray] (BBB)at (\xc+\r,\yc) {};
\node[circle, radius=0.15cm, label=B, fill=gray] (B) at (\xc+\dBx,\yc+\dBy) {};
\node[circle, radius=0.15cm, label=below:B, fill=gray] (BBBB)at (\xc+\dBx,\yc-\dBy) {};
\end{tikzpicture}
\end{document}

Best Answer

shape border rotate is the parameter that you can use to rotate a shape node. But in this case, you also need to change where labels are placed.

Unfortunately this answer will change all your code. It uses hexagon corners as reference points and also as anchors to place them one over the other. Hope it helps.

First example is not rotated and second one has a 30 degree rotation.

\documentclass[border=2mm,tikz]{standalone}
\usepackage{tikz}
\usetikzlibrary{shapes}
\begin{document}
\begin{tikzpicture}[%
    point/.style={circle, radius=0.15cm, fill=#1},    
    hex/.style={draw, regular polygon, regular polygon sides=6,minimum size=3 cm}]

\node[hex] (A) {};
\node[hex, anchor=corner 4] (B) at (A.corner 2) {};
\node[hex, anchor=corner 6] (C) at (A.corner 2) {};

\foreach \i/\j/\k in {
    B/1/above, B/3/above, B/5/right,
    C/3/above, C/5/below, A/5/below}
    \node[point=black, label=\k:A] at (\i.corner \j) {};

\foreach \i/\j/\k in {
    B/2/above, B/4/above, B/6/right,
    C/2/above, C/4/below, A/4/below, A/6/right}
    \node[point=gray, label=\k:B] at (\i.corner \j) {};

\end{tikzpicture}

\begin{tikzpicture}[%
    point/.style={circle, radius=0.15cm, fill=#1},    
    hex/.style={draw, regular polygon, regular polygon sides=6,minimum size=3 cm, shape border rotate=30}]

\node[hex] (A) {};
\node[hex, anchor=corner 4] (B) at (A.corner 2) {};
\node[hex, anchor=corner 6] (C) at (A.corner 2) {};

\foreach \i/\j/\k in {
    B/1/above, B/3/left, B/5/right,
    C/3/below, C/5/below, A/5/below}
    \node[point=black, label=\k:A] at (\i.corner \j) {};

\foreach \i/\j/\k in {
    B/2/above, B/4/above, B/6/right,
    C/2/above, C/4/below, A/4/below, A/6/right}
    \node[point=gray, label=\k:B] at (\i.corner \j) {};

\end{tikzpicture}

\end{document}

Related Solutions

[Tex/LaTex] Generate regular polygon

You need to use the shapes.geometric library in order to use the regular polygon shape. After that your code should work just fine.

[Tex/LaTex] TikZ: Drawing an arc from an intersection to an intersection

A solution which allows to draw intersection segments of any two intersections is available as tikz library fillbetween.

This library works as general purpose tikz library, but it is shipped with pgfplots and you need to load pgfplots in order to make it work:

\documentclass{standalone}

\usepackage{tikz}
\usepackage{pgfplots}
\usetikzlibrary{fillbetween}

\begin{document}

\begin{tikzpicture}

\draw [name path=red,red] (120:1.06) circle (1.9);
%\draw [name path=yellow,yellow] (0:1.06) circle (2.12);
\draw [name path=green,green!50!black] (0:0.77) circle (2.41);
\draw [name path=blue,blue] (0:0) circle (1.06);

% substitute this temp path by `\path` to make it invisible:
\draw[name path=temp1, intersection segments={of=red and blue,sequence=L1}];
\draw[red,-stealth,ultra thick, intersection segments={of=temp1 and green,sequence=L3}];

\end{tikzpicture}

\end{document}

enter image description here

The key intersection segments is described in all detail in the pgfplots reference manual section "5.6.6 Intersection Segment Recombination"; the key idea in this case is to

create a temporary path temp1 which is the first intersection segment of red and blue, more precisely, it is the first intersection segment in the Left argument in red and blue : red. This path is drawn as thin black path. Substitute its \draw statement by \path to make it invisible.
Compute the desired intersection segment by intersecting temp1 and green and use the correct intersection segment. By trial and error I figured that it is the third segment of path temp1 which is written as L3 (L = left argument in temp1 and green and 3 means third segment of that path).

The argument involves some trial and error because fillbetween is unaware of the fact that end and startpoint are connected -- and we as end users do not see start and end point.

Note that you can connect these path segments with other paths. If such an intersection segment should be the continuation of another path, use -- as before the first argument in sequence. This allows to fill paths segments:

\documentclass{standalone}

\usepackage{tikz}
\usepackage{pgfplots}
\usetikzlibrary{fillbetween}

\begin{document}

\begin{tikzpicture}

\draw [name path=red,red] (120:1.06) circle (1.9);
%\draw [name path=yellow,yellow] (0:1.06) circle (2.12);
\draw [name path=green,green!50!black] (0:0.77) circle (2.41);
\draw [name path=blue,blue] (0:0) circle (1.06);

% substitute this temp path by `\path` to make it invisible:
\draw[name path=temp1, intersection segments={of=red and blue,sequence=L1}];
\draw[red,fill=blue,-stealth,ultra thick, intersection segments={of=temp1 and green,sequence=L3}]  
    [intersection segments={of=temp1 and green, sequence={--R2}}]
;

\end{tikzpicture}

\end{document}

enter image description here

Best Answer

Related Solutions

[Tex/LaTex] Generate regular polygon

[Tex/LaTex] TikZ: Drawing an arc from an intersection to an intersection

Related Question