Quero criar uma versão flangeada de tubos 3D que se pareçaa foto da postagem original. Minha tentativa de "força bruta" é a seguinte:
\documentclass[tikz]{standalone}
\begin{document}
\begin{tikzpicture}
\definecolor{LPtgrey}{rgb}{.7,.7,.7}
\def\pipesize{1cm}
\def\flangesize{1.75*\pipesize}
\def\ft{0.2} % for flange thickness
\def\fg{0.02} % for flange gap
\def\xx{0.5} % length of middle of bend to inside edge of flange, ie, same as bend radius
\pgfsetcornersarced{\pgfpoint{0.5cm}{0.5cm}}
%pipe
\draw[color=LPtgrey!80!black, line width=\pipesize*0.4] (2,0)--(2,6)--(5,6)--(7,4)--(9,4);%
\draw[color=LPtgrey, line width=\pipesize*0.38] (2,0)--(2,6)--(5,6)--(7,4)--(9,4);%
\draw[color=LPtgrey!85, line width=\pipesize*0.35] (2,0)--(2,6)--(5,6)--(7,4)--(9,4);%
\draw[color=LPtgrey!70, line width=\pipesize*0.32] (2,0)--(2,6)--(5,6)--(7,4)--(9,4);%
\draw[color=LPtgrey!55, line width=\pipesize*0.29] (2,0)--(2,6)--(5,6)--(7,4)--(9,4);%
\draw[color=LPtgrey!45, line width=\pipesize*0.25] (2,0)--(2,6)--(5,6)--(7,4)--(9,4);%
\draw[color=LPtgrey!35, line width=\pipesize*0.20] (2,0)--(2,6)--(5,6)--(7,4)--(9,4);%
%flange 1
\draw[color=LPtgrey!80!black, line width=\flangesize*0.4] (2,0)--(2,0+\ft);%
\draw[color=LPtgrey, line width=\flangesize*0.38] (2,0)--(2,0+\ft);%
\draw[color=LPtgrey!85, line width=\flangesize*0.35] (2,0)--(2,0+\ft);%
\draw[color=LPtgrey!70, line width=\flangesize*0.32] (2,0)--(2,0+\ft);%
\draw[color=LPtgrey!55, line width=\flangesize*0.29] (2,0)--(2,0+\ft);%
\draw[color=LPtgrey!45, line width=\flangesize*0.25] (2,0)--(2,0+\ft);%
\draw[color=LPtgrey!35, line width=\flangesize*0.20] (2,0)--(2,0+\ft);%
%flange 2
\draw[color=LPtgrey!80!black, line width=\flangesize*0.4] (2,6-\xx-\ft-\fg-\ft)--(2,6-\xx-\ft-\fg);%
\draw[color=LPtgrey, line width=\flangesize*0.38] (2,6-\xx-\ft-\fg-\ft)--(2,6-\xx-\ft-\fg);%
\draw[color=LPtgrey!85, line width=\flangesize*0.35] (2,6-\xx-\ft-\fg-\ft)--(2,6-\xx-\ft-\fg);%
\draw[color=LPtgrey!70, line width=\flangesize*0.32] (2,6-\xx-\ft-\fg-\ft)--(2,6-\xx-\ft-\fg);%
\draw[color=LPtgrey!55, line width=\flangesize*0.29] (2,6-\xx-\ft-\fg-\ft)--(2,6-\xx-\ft-\fg);%
\draw[color=LPtgrey!45, line width=\flangesize*0.25] (2,6-\xx-\ft-\fg-\ft)--(2,6-\xx-\ft-\fg);%
\draw[color=LPtgrey!35, line width=\flangesize*0.20] (2,6-\xx-\ft-\fg-\ft)--(2,6-\xx-\ft-\fg);%
%flange 3
\draw[color=LPtgrey!80!black, line width=\flangesize*0.4] (2,6-\xx-\ft)--(2,6-\xx);%
\draw[color=LPtgrey, line width=\flangesize*0.38] (2,6-\xx-\ft)--(2,6-\xx);%
\draw[color=LPtgrey!85, line width=\flangesize*0.35] (2,6-\xx-\ft)--(2,6-\xx);%
\draw[color=LPtgrey!70, line width=\flangesize*0.32] (2,6-\xx-\ft)--(2,6-\xx);%
\draw[color=LPtgrey!55, line width=\flangesize*0.29] (2,6-\xx-\ft)--(2,6-\xx);%
\draw[color=LPtgrey!45, line width=\flangesize*0.25] (2,6-\xx-\ft)--(2,6-\xx);%
\draw[color=LPtgrey!35, line width=\flangesize*0.20] (2,6-\xx-\ft)--(2,6-\xx);%
%flange 4
\draw[color=LPtgrey!80!black, line width=\flangesize*0.4] (2+\xx,6)--(2+\xx+\ft,6);%
\draw[color=LPtgrey, line width=\flangesize*0.38] (2+\xx,6)--(2+\xx+\ft,6);%
\draw[color=LPtgrey!85, line width=\flangesize*0.35] (2+\xx,6)--(2+\xx+\ft,6);%
\draw[color=LPtgrey!70, line width=\flangesize*0.32] (2+\xx,6)--(2+\xx+\ft,6);%
\draw[color=LPtgrey!55, line width=\flangesize*0.29] (2+\xx,6)--(2+\xx+\ft,6);%
\draw[color=LPtgrey!45, line width=\flangesize*0.25] (2+\xx,6)--(2+\xx+\ft,6);%
\draw[color=LPtgrey!35, line width=\flangesize*0.20] (2+\xx,6)--(2+\xx+\ft,6);%
%flange 5
\draw[color=LPtgrey!80!black, line width=\flangesize*0.4] (2+\xx+\ft+\fg,6)--(2+\xx+\ft+\fg+\ft,6);%
\draw[color=LPtgrey, line width=\flangesize*0.38] (2+\xx+\ft+\fg,6)--(2+\xx+\ft+\fg+\ft,6);%
\draw[color=LPtgrey!85, line width=\flangesize*0.35] (2+\xx+\ft+\fg,6)--(2+\xx+\ft+\fg+\ft,6);%
\draw[color=LPtgrey!70, line width=\flangesize*0.32] (2+\xx+\ft+\fg,6)--(2+\xx+\ft+\fg+\ft,6);%
\draw[color=LPtgrey!55, line width=\flangesize*0.29] (2+\xx+\ft+\fg,6)--(2+\xx+\ft+\fg+\ft,6);%
\draw[color=LPtgrey!45, line width=\flangesize*0.25] (2+\xx+\ft+\fg,6)--(2+\xx+\ft+\fg+\ft,6);%
\draw[color=LPtgrey!35, line width=\flangesize*0.20] (2+\xx+\ft+\fg,6)--(2+\xx+\ft+\fg+\ft,6);%
%flange 6
\draw[color=LPtgrey!80!black, line width=\flangesize*0.4] (5-\xx-\ft-\fg-\ft,6)--(5-\xx-\ft-\fg,6);%
\draw[color=LPtgrey, line width=\flangesize*0.38] (5-\xx-\ft-\fg-\ft,6)--(5-\xx-\ft-\fg,6);%
\draw[color=LPtgrey!85, line width=\flangesize*0.35] (5-\xx-\ft-\fg-\ft,6)--(5-\xx-\ft-\fg,6);%
\draw[color=LPtgrey!70, line width=\flangesize*0.32] (5-\xx-\ft-\fg-\ft,6)--(5-\xx-\ft-\fg,6);%
\draw[color=LPtgrey!55, line width=\flangesize*0.29] (5-\xx-\ft-\fg-\ft,6)--(5-\xx-\ft-\fg,6);%
\draw[color=LPtgrey!45, line width=\flangesize*0.25] (5-\xx-\ft-\fg-\ft,6)--(5-\xx-\ft-\fg,6);%
\draw[color=LPtgrey!35, line width=\flangesize*0.20] (5-\xx-\ft-\fg-\ft,6)--(5-\xx-\ft-\fg,6);%
%flange 7
\draw[color=LPtgrey!80!black, line width=\flangesize*0.4] (5-\xx-\ft,6)--(5-\xx,6);%
\draw[color=LPtgrey, line width=\flangesize*0.38] (5-\xx-\ft,6)--(5-\xx,6);%
\draw[color=LPtgrey!85, line width=\flangesize*0.35] (5-\xx-\ft,6)--(5-\xx,6);%
\draw[color=LPtgrey!70, line width=\flangesize*0.32] (5-\xx-\ft,6)--(5-\xx,6);%
\draw[color=LPtgrey!55, line width=\flangesize*0.29] (5-\xx-\ft,6)--(5-\xx,6);%
\draw[color=LPtgrey!45, line width=\flangesize*0.25] (5-\xx-\ft,6)--(5-\xx,6);%
\draw[color=LPtgrey!35, line width=\flangesize*0.20] (5-\xx-\ft,6)--(5-\xx,6);%
%flange 8
\draw[color=LPtgrey!80!black, line width=\flangesize*0.4] (5+\xx,6-\xx)--(5+\xx+\ft,6-\xx-\ft);%
\draw[color=LPtgrey, line width=\flangesize*0.38] (5+\xx,6-\xx)--(5+\xx+\ft,6-\xx-\ft);%
\draw[color=LPtgrey!85, line width=\flangesize*0.35] (5+\xx,6-\xx)--(5+\xx+\ft,6-\xx-\ft);%
\draw[color=LPtgrey!70, line width=\flangesize*0.32] (5+\xx,6-\xx)--(5+\xx+\ft,6-\xx-\ft);%
\draw[color=LPtgrey!55, line width=\flangesize*0.29] (5+\xx,6-\xx)--(5+\xx+\ft,6-\xx-\ft);%
\draw[color=LPtgrey!45, line width=\flangesize*0.25] (5+\xx,6-\xx)--(5+\xx+\ft,6-\xx-\ft);%
\draw[color=LPtgrey!35, line width=\flangesize*0.20] (5+\xx,6-\xx)--(5+\xx+\ft,6-\xx-\ft);%
%flange 9
\draw[color=LPtgrey!80!black, line width=\flangesize*0.4] (5+\xx+\ft+\fg,6-\xx-\ft-\fg)--(5+\xx+\ft+\fg+\ft,6-\xx-\ft-\fg-\ft);%
\draw[color=LPtgrey, line width=\flangesize*0.38] (5+\xx+\ft+\fg,6-\xx-\ft-\fg)--(5+\xx+\ft+\fg+\ft,6-\xx-\ft-\fg-\ft);%
\draw[color=LPtgrey!85, line width=\flangesize*0.35] (5+\xx+\ft+\fg,6-\xx-\ft-\fg)--(5+\xx+\ft+\fg+\ft,6-\xx-\ft-\fg-\ft);%
\draw[color=LPtgrey!70, line width=\flangesize*0.32] (5+\xx+\ft+\fg,6-\xx-\ft-\fg)--(5+\xx+\ft+\fg+\ft,6-\xx-\ft-\fg-\ft);%
\draw[color=LPtgrey!55, line width=\flangesize*0.29] (5+\xx+\ft+\fg,6-\xx-\ft-\fg)--(5+\xx+\ft+\fg+\ft,6-\xx-\ft-\fg-\ft);%
\draw[color=LPtgrey!45, line width=\flangesize*0.25] (5+\xx+\ft+\fg,6-\xx-\ft-\fg)--(5+\xx+\ft+\fg+\ft,6-\xx-\ft-\fg-\ft);%
\draw[color=LPtgrey!35, line width=\flangesize*0.20] (5+\xx+\ft+\fg,6-\xx-\ft-\fg)--(5+\xx+\ft+\fg+\ft,6-\xx-\ft-\fg-\ft);%
%flange 10
\draw[color=LPtgrey!80!black, line width=\flangesize*0.4] (7-\xx-\ft-\fg-\ft,4+\xx+\ft+\fg+\ft)--(7-\xx-\ft-\fg,4+\xx+\ft+\fg);%
\draw[color=LPtgrey, line width=\flangesize*0.38] (7-\xx-\ft-\fg-\ft,4+\xx+\ft+\fg+\ft)--(7-\xx-\ft-\fg,4+\xx+\ft+\fg);%
\draw[color=LPtgrey!85, line width=\flangesize*0.35] (7-\xx-\ft-\fg-\ft,4+\xx+\ft+\fg+\ft)--(7-\xx-\ft-\fg,4+\xx+\ft+\fg);%
\draw[color=LPtgrey!70, line width=\flangesize*0.32] (7-\xx-\ft-\fg-\ft,4+\xx+\ft+\fg+\ft)--(7-\xx-\ft-\fg,4+\xx+\ft+\fg);%
\draw[color=LPtgrey!55, line width=\flangesize*0.29] (7-\xx-\ft-\fg-\ft,4+\xx+\ft+\fg+\ft)--(7-\xx-\ft-\fg,4+\xx+\ft+\fg);%
\draw[color=LPtgrey!45, line width=\flangesize*0.25] (7-\xx-\ft-\fg-\ft,4+\xx+\ft+\fg+\ft)--(7-\xx-\ft-\fg,4+\xx+\ft+\fg);%
\draw[color=LPtgrey!35, line width=\flangesize*0.20] (7-\xx-\ft-\fg-\ft,4+\xx+\ft+\fg+\ft)--(7-\xx-\ft-\fg,4+\xx+\ft+\fg);%
%flange 11
\draw[color=LPtgrey!80!black, line width=\flangesize*0.4] (7-\xx-\ft,4+\xx+\ft)--(7-\xx,4+\xx);%
\draw[color=LPtgrey, line width=\flangesize*0.38] (7-\xx-\ft,4+\xx+\ft)--(7-\xx,4+\xx);%
\draw[color=LPtgrey!85, line width=\flangesize*0.35] (7-\xx-\ft,4+\xx+\ft)--(7-\xx,4+\xx);%
\draw[color=LPtgrey!70, line width=\flangesize*0.32] (7-\xx-\ft,4+\xx+\ft)--(7-\xx,4+\xx);%
\draw[color=LPtgrey!55, line width=\flangesize*0.29] (7-\xx-\ft,4+\xx+\ft)--(7-\xx,4+\xx);%
\draw[color=LPtgrey!45, line width=\flangesize*0.25] (7-\xx-\ft,4+\xx+\ft)--(7-\xx,4+\xx);%
\draw[color=LPtgrey!35, line width=\flangesize*0.20] (7-\xx-\ft,4+\xx+\ft)--(7-\xx,4+\xx);%
%flange 12
\draw[color=LPtgrey!80!black, line width=\flangesize*0.4] (7+\xx,4)--(7+\xx+\ft,4);%
\draw[color=LPtgrey, line width=\flangesize*0.38] (7+\xx,4)--(7+\xx+\ft,4);%
\draw[color=LPtgrey!85, line width=\flangesize*0.35] (7+\xx,4)--(7+\xx+\ft,4);%
\draw[color=LPtgrey!70, line width=\flangesize*0.32] (7+\xx,4)--(7+\xx+\ft,4);%
\draw[color=LPtgrey!55, line width=\flangesize*0.29] (7+\xx,4)--(7+\xx+\ft,4);%
\draw[color=LPtgrey!45, line width=\flangesize*0.25] (7+\xx,4)--(7+\xx+\ft,4);%
\draw[color=LPtgrey!35, line width=\flangesize*0.20] (7+\xx,4)--(7+\xx+\ft,4);%
%flange 13
\draw[color=LPtgrey!80!black, line width=\flangesize*0.4] (7+\xx+\ft+\fg,4)--(7+\xx+\ft+\fg+\ft,4);%
\draw[color=LPtgrey, line width=\flangesize*0.38] (7+\xx+\ft+\fg,4)--(7+\xx+\ft+\fg+\ft,4);%
\draw[color=LPtgrey!85, line width=\flangesize*0.35] (7+\xx+\ft+\fg,4)--(7+\xx+\ft+\fg+\ft,4);%
\draw[color=LPtgrey!70, line width=\flangesize*0.32] (7+\xx+\ft+\fg,4)--(7+\xx+\ft+\fg+\ft,4);%
\draw[color=LPtgrey!55, line width=\flangesize*0.29] (7+\xx+\ft+\fg,4)--(7+\xx+\ft+\fg+\ft,4);%
\draw[color=LPtgrey!45, line width=\flangesize*0.25] (7+\xx+\ft+\fg,4)--(7+\xx+\ft+\fg+\ft,4);%
\draw[color=LPtgrey!35, line width=\flangesize*0.20] (7+\xx+\ft+\fg,4)--(7+\xx+\ft+\fg+\ft,4);%
%flange 14
\draw[color=LPtgrey!80!black, line width=\flangesize*0.4] (9-\ft,4)--(9,4);%
\draw[color=LPtgrey, line width=\flangesize*0.38] (9-\ft,4)--(9,4);%
\draw[color=LPtgrey!85, line width=\flangesize*0.35] (9-\ft,4)--(9,4);%
\draw[color=LPtgrey!70, line width=\flangesize*0.32] (9-\ft,4)--(9,4);%
\draw[color=LPtgrey!55, line width=\flangesize*0.29] (9-\ft,4)--(9,4);%
\draw[color=LPtgrey!45, line width=\flangesize*0.25] (9-\ft,4)--(9,4);%
\draw[color=LPtgrey!35, line width=\flangesize*0.20] (9-\ft,4)--(9,4);%
\end{tikzpicture}
\end{document}
o resultado é ok:
A força bruta funciona bem para curvas de 90 graus, mas ângulos de 45 graus têm flanges muito grossos. Outros ângulos requerem muita trigonometria para calcular as posições dos flanges.
Deve haver uma forma de definir um "estilo de linha" que é a combinação de 5 linhas sobrepostas (não sei como).
Deve haver uma maneira de definir uma decoração personalizada que termine cada linha (ou cada nó de uma polilinha) para obter o resultado desejado. A decoração giraria para ficar no mesmo ângulo da linha?
Idealmente, eu gostaria de usar código como:
\draw[pipe,style=flange,diameter=3cm](2,0)--(2,6)--(5,6);
e toda a matemática associada à colocação de flanges seria resolvida. Estarei desenhando MUITOS diagramas de tubos em um futuro próximo e agradeceria qualquer código útil que tornasse isso mais fácil.
Responder1
Duas abordagens são demonstradas aqui. Ambos usam repetidamente a preactionchave com diferentes larguras e cores de linha para desenhar o tubo (e também o flange). A primeira abordagem utiliza a markingsdecoração como forma postactionde posicionar as flanges. A segunda utiliza a show path constructiondecoração para posicionar flanges no início e no final dos segmentos linetoe curveto.
\documentclass[tikz,border=5]{standalone}
\usetikzlibrary{decorations.markings,decorations.pathreplacing,calc}
\makeatletter
\tikzset{every pipe/.code={%
\pgfmathloop
\ifnum\pgfmathcounter>20
\else
\pgfmathsetmacro\i{\pgfmathcounter}%
\pgfmathsetmacro\j{80-\pgfmathcounter*3}%
\tikzset{preaction/.expanded={line width=(\pipewidth)*(1-\i*\i/500),
draw=black!50!white!\j!white}}%
\repeatpgfmathloop
},
every flange/.style 2 args={insert path={
let \p1=(#1), \p2=(#2),\n1={atan2(\y2-\y1, \x2-\x1)} in
[shift={(\p1)}, rotate=\n1, pipe width={(\pipewidth)*4/3}, every pipe]
(0.01,0) -- (0.2,0)
}},
flanges/.style={postaction={%
/utils/exec={
\@for\pos:=#1\do{%
\tikzset{decoration/.expanded={markings,
mark=at position \pos\space with {
\noexpand\path [pipe width=\pipewidth*4/3, every pipe] (0.01,0) -- (0.2,0);
}}}}},
decorate}},
pipe width/.code=\pgfmathsetlengthmacro\pipewidth{#1},
pipes/.style={
every pipe,
postaction={decoration={show path construction,
lineto code={
\path [every flange={\tikzinputsegmentfirst}{\tikzinputsegmentlast}];
\path [every flange={\tikzinputsegmentlast}{\tikzinputsegmentfirst}];
},
curveto code={
\path [every flange={\tikzinputsegmentfirst}{\tikzinputsegmentsupporta}];
\path [every flange={\tikzinputsegmentlast}{\tikzinputsegmentsupportb}];
}
}, decorate}},
pipe/.style={
every pipe,
flanges={0, 1}
}}
\begin{document}
\begin{tikzpicture}[line join=round, pipe width=0.5cm]
\path [pipes] (0,4) -- (0,1) arc (180:330:1) (-1,3) -- (1,3);
\path [pipes] (3,-1/3) -- (3,2);
\path [pipes] (4,-1/3) -- (4,4);
\path [pipe] (11/2,3) -- (4,5/4) -- (11/2,0);
\path [pipe] (13/2,5/2) -- (8,5/2) -- (13/2,0) -- (8,0);
\path [pipes] (4,2) ellipse [x radius=6, y radius=4];
\end{tikzpicture}
\end{document}
