%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% Copyright (C) 2018 Theodore Chang
%%
%% This program is free software: you can redistribute it and/or modify
%% it under the terms of the GNU General Public License as published by
%% the Free Software Foundation, either version 3 of the License, or
%% (at your option) any later version.
%%
%% This program is distributed in the hope that it will be useful,
%% but WITHOUT ANY WARRANTY; without even the implied warranty of
%% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
%% GNU General Public License for more details.
%%
%% You should have received a copy of the GNU General Public License
%% along with this program.  If not, see <http://www.gnu.org/licenses/>.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% structmech: A TikZ command set for structural mechanics drawings
%                                           v0.1   by   tlc
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\NeedsTeXFormat{LaTeX2e}
\ProvidesPackage{structmech}[2018/04/07 structmech: A TikZ command set for structural mechanics drawings]
\RequirePackage{tikz}
\RequirePackage{tikz-3dplot}
\RequirePackage{ifthen}
\RequirePackage{xparse}
\RequirePackage{xstring}
\RequirePackage{kvoptions}
\RequirePackage{xkeyval}
\usetikzlibrary{backgrounds,calc,positioning,arrows.meta,decorations.pathreplacing,decorations.pathmorphing,shapes.arrows}
\definecolor{0066CC}{RGB}{0,102,204}
\definecolor{00CC66}{RGB}{0,204,102}
\definecolor{CC0066}{RGB}{204,0,102}
\definecolor{CC6600}{RGB}{204,102,0}
\DeclareOptionX<structmech>{axial}[CC0066]{\def\axialColor{#1}}
\DeclareOptionX<structmech>{rotation}[00CC66]{\def\rotColor{#1}}
\DeclareOptionX<structmech>{node}[0066CC]{\def\nodalColor{#1}}
\DeclareOptionX<structmech>{fill}[CC0066]{\def\fillColor{#1}}
\DeclareOptionX<structmech>{convention}[sign]{\IfStrEq{#1}{sign}{\def\convention{#1}}{}\IfStrEq{#1}{direction}{\def\convention{#1}}{}}
\ExecuteOptionsX<structmech>{axial,rotation,node,convention,fill}
\ProcessOptionsX<structmech>
\tikzset{
     BMD/.style={draw=0066CC,fill=0066CC,fill opacity=.4},
  NOFILL/.style={fill=none,fill opacity=1},
RotBasic/.style={\rotColor,line width=.4mm,->},
   FIXED/.style={postaction={draw,decorate,decoration={border,pre length=1mm,post length=1mm,angle=-60,amplitude=1mm,segment length=1mm}}}
}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%     Command Zero: Set options.
% \setstructmech{1}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\NewDocumentCommand{\setstructmech}{m}{\ExecuteOptionsX<structmech>{#1}}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%     Command 1: Label All Nodal Forces.
% \NodalForce[1]{2}[3][4][5]{6}[7]
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\NewDocumentCommand{\NodalForce}{O{\nodalColor} m O{} O{} O{} G{0} O{1}}{
\begin{scope}[rotate around={#6:(#2)},shift={(#2)},scale=#7]
\IfEq{#3}{}
	{\draw[#1,line width=.4mm,->](-1,0)--(-.2,0);}
	{\IfEq{#3}{N}
		{}
		{\IfStrEq{\convention}{sign}
			{\draw[#1,line width=.4mm,->](-1,0)--(-.2,0);\node[fill=none,#1]at(-1.4,0){\footnotesize$#3$};}
			{\StrLeft{#3}{1}[\SS]\IfStrEq{\SS}{-}
				{\draw[#1,line width=.4mm,->](-.2,0)--(-1,0);\node[fill=none,#1]at(-1.4,0){\footnotesize$\StrDel[1]{#3}{-}$};}
				{\draw[#1,line width=.4mm,->](-1,0)--(-.2,0);\node[fill=none,#1]at(-1.4,0){\footnotesize$#3$};}
			}
		}
	}
\IfEq{#4}{}
	{\draw[#1,line width=.4mm,->](0,-1)--(0,-.2);}
	{\IfEq{#4}{N}
		{}
		{\IfStrEq{\convention}{sign}
			{\draw[#1,line width=.4mm,->](0,-1)--(0,-.2);\node[fill=none,#1]at(0,-1.4){\footnotesize$#4$};}
			{\StrLeft{#4}{1}[\SS]\IfStrEq{\SS}{-}
				{\draw[#1,line width=.4mm,->](0,-.2)--(0,-1);\node[fill=none,#1]at(0,-1.4){\footnotesize$\StrDel[1]{#4}{-}$};}
				{\draw[#1,line width=.4mm,->](0,-1)--(0,-.2);\node[fill=none,#1]at(0,-1.4){\footnotesize$#4$};}
			}
		}
	}
\IfEq{#5}{}
	{\draw[#1,line width=.4mm,->](.2121,-.2121)arc[#1,start angle=-45,end angle=135,radius=3mm];}
	{\IfEq{#5}{N}
		{}
		{\IfStrEq{\convention}{sign}
			{\draw[#1,line width=.4mm,->](.2121,-.2121)arc[#1,start angle=-45,end angle=135,radius=3mm];\node[#1,fill=none]at(-.5303,.5303){\footnotesize$#5$};}
			{\StrLeft{#5}{1}[\SS]\IfStrEq{\SS}{-}
				{\draw[#1,line width=.4mm,<-](.2121,-.2121)arc[#1,start angle=-45,end angle=135,radius=3mm];\node[#1,fill=none]at(-.5303,.5303){\footnotesize$\StrDel[1]{#5}{-}$};}
				{\draw[#1,line width=.4mm,->](.2121,-.2121)arc[#1,start angle=-45,end angle=135,radius=3mm];\node[#1,fill=none]at(-.5303,.5303){\footnotesize$#5$};}
			}
		}
	}
\end{scope}
}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%     Command 2: Label Element Forces.
% \BasicForce[1]{2}{3}{4}{5}[6][7][8]
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\NewDocumentCommand{\BasicForce}{O{3} m m m G{above=2mm} o o o}{
\coordinate(A)at(#2);
\coordinate(B)at(#3);
\pgfmathanglebetweenpoints{\pgfpointanchor{A}{center}}{\pgfpointanchor{B}{center}}
\let\Angle\pgfmathresult
\tikzset{
EndRotA/.style={start angle=\Angle+90,end angle=\Angle+270,radius=3mm},
EndRotB/.style={start angle=\Angle-90,end angle=\Angle+90,radius=3mm},
EndRotC/.style={start angle=\Angle+270,end angle=\Angle+90,radius=3mm},
EndRotD/.style={start angle=\Angle+90,end angle=\Angle-90,radius=3mm},
}
\IfEq{#1}{1}
	{
	\IfNoValueTF{#6}
		{\draw[\axialColor,line width=.4mm,<->](#2)--(#3)node[midway,fill=none,#5]{$#4$};}
		{\IfStrEq{\convention}{sign}
			{\draw[\axialColor,line width=.4mm,<->](#2)--(#3)node[midway,fill=none,#5]{$#4$}node[midway,fill=white]{\footnotesize$#6$};}
			{\StrLeft{#6}{1}[\SS]\IfStrEq{\SS}{-}
				{\draw[\axialColor,line width=.4mm,>-<](#2)--(#3)node[midway,fill=none,#5]{$#4$}node[midway,fill=white]{\footnotesize$\StrDel[1]{#6}{-}$};}
				{\draw[\axialColor,line width=.4mm,<->](#2)--(#3)node[midway,fill=none,#5]{$#4$}node[midway,fill=white]{\footnotesize$#6$};}
			}
		}
	}
	{}
\IfEq{#1}{2L}
	{
	\draw[\axialColor,draw=none](#2)--(#3)node[midway,fill=none,#5]{$#4$};
	\IfNoValueTF{#6}
		{\draw[RotBasic]($(#2)+(\Angle+90:.3)$)arc[EndRotA];}
		{\IfStrEq{\convention}{sign}
			{\node[fill=none,\rotColor]at($(#2)+(\Angle+90:.6)$){\footnotesize$#6$};\draw[RotBasic]($(#2)+(\Angle+90:.3)$)arc[EndRotA];}
			{\StrLeft{#6}{1}[\SS]\IfStrEq{\SS}{-}
				{\node[fill=none,\rotColor]at($(#2)+(\Angle-90:.6)$){\footnotesize$\StrDel[1]{#6}{-}$};\draw[RotBasic]($(#2)+(\Angle-90:.3)$)arc[EndRotC];}
				{\node[fill=none,\rotColor]at($(#2)+(\Angle+90:.6)$){\footnotesize$#6$};\draw[RotBasic]($(#2)+(\Angle+90:.3)$)arc[EndRotA];}
			}
		}
	}
	{}
\IfEq{#1}{2H}
	{
	\draw[\axialColor,draw=none](#2)--(#3)node[midway,fill=none,#5]{$#4$};
	\IfNoValueTF{#6}
		{\draw[RotBasic]($(#3)+(\Angle-90:.3)$)arc[EndRotB];}
		{\IfStrEq{\convention}{sign}
			{\node[fill=none,\rotColor]at($(#3)+(\Angle-90:.6)$){\footnotesize$#6$};\draw[RotBasic]($(#3)+(\Angle-90:.3)$)arc[EndRotB];}
			{\StrLeft{#6}{1}[\SS]\IfStrEq{\SS}{-}
				{\node[fill=none,\rotColor]at($(#3)+(\Angle+90:.6)$){\footnotesize$\StrDel[1]{#6}{-}$};\draw[RotBasic]($(#3)+(\Angle+90:.3)$)arc[EndRotD];}
				{\node[fill=none,\rotColor]at($(#3)+(\Angle-90:.6)$){\footnotesize$#6$};\draw[RotBasic]($(#3)+(\Angle-90:.3)$)arc[EndRotB];}
			}
		}
	}
	{}
\IfEq{#1}{2}
	{
	\draw[\axialColor,draw=none](#2)--(#3)node[midway,fill=none,#5]{$#4$};
	\IfNoValueTF{#6}
		{\draw[RotBasic]($(#2)+(\Angle+90:.3)$)arc[EndRotA];}
		{\IfStrEq{\convention}{sign}
			{\node[fill=none,\rotColor]at($(#2)+(\Angle+90:.6)$){\footnotesize$#6$};\draw[RotBasic]($(#2)+(\Angle+90:.3)$)arc[EndRotA];}
			{\StrLeft{#6}{1}[\SS]\IfStrEq{\SS}{-}
				{\node[fill=none,\rotColor]at($(#2)+(\Angle-90:.6)$){\footnotesize$\StrDel[1]{#6}{-}$};\draw[RotBasic]($(#2)+(\Angle-90:.3)$)arc[EndRotC];}
				{\node[fill=none,\rotColor]at($(#2)+(\Angle+90:.6)$){\footnotesize$#6$};\draw[RotBasic]($(#2)+(\Angle+90:.3)$)arc[EndRotA];}
			}
		}
	\IfNoValueTF{#7}
		{\draw[RotBasic]($(#3)+(\Angle-90:.3)$)arc[EndRotB];}
		{\IfStrEq{\convention}{sign}
			{\node[fill=none,\rotColor]at($(#3)+(\Angle-90:.6)$){\footnotesize$#7$};\draw[RotBasic]($(#3)+(\Angle-90:.3)$)arc[EndRotB];}
			{\StrLeft{#7}{1}[\SS]\IfStrEq{\SS}{-}
				{\node[fill=none,\rotColor]at($(#3)+(\Angle+90:.6)$){\footnotesize$\StrDel[1]{#7}{-}$};\draw[RotBasic]($(#3)+(\Angle+90:.3)$)arc[EndRotD];}
				{\node[fill=none,\rotColor]at($(#3)+(\Angle-90:.6)$){\footnotesize$#7$};\draw[RotBasic]($(#3)+(\Angle-90:.3)$)arc[EndRotB];}
			}
		}
	}
	{}
\IfEq{#1}{3}
	{
	\IfNoValueTF{#6}
		{\draw[\axialColor,line width=.4mm,<->](#2)--(#3)node[midway,fill=none,#5]{$#4$};}
		{\IfStrEq{\convention}{sign}
			{\draw[\axialColor,line width=.4mm,<->](#2)--(#3)node[midway,fill=none,#5]{$#4$}node[midway,fill=white]{\footnotesize$#6$};}
			{\StrLeft{#6}{1}[\SS]\IfStrEq{\SS}{-}
				{\draw[\axialColor,line width=.4mm,>-<](#2)--(#3)node[midway,fill=none,#5]{$#4$}node[midway,fill=white]{\footnotesize$\StrDel[1]{#6}{-}$};}
				{\draw[\axialColor,line width=.4mm,<->](#2)--(#3)node[midway,fill=none,#5]{$#4$}node[midway,fill=white]{\footnotesize$#6$};}
			}
		}
	\IfNoValueTF{#7}
		{\draw[RotBasic]($(#2)+(\Angle+90:.3)$)arc[EndRotA];}
		{\IfStrEq{\convention}{sign}
			{\node[fill=none,\rotColor]at($(#2)+(\Angle+90:.6)$){\footnotesize$#7$};\draw[RotBasic]($(#2)+(\Angle+90:.3)$)arc[EndRotA];}
			{\StrLeft{#7}{1}[\SS]\IfStrEq{\SS}{-}
				{\node[fill=none,\rotColor]at($(#2)+(\Angle-90:.6)$){\footnotesize$\StrDel[1]{#7}{-}$};\draw[RotBasic]($(#2)+(\Angle-90:.3)$)arc[EndRotC];}
				{\node[fill=none,\rotColor]at($(#2)+(\Angle+90:.6)$){\footnotesize$#7$};\draw[RotBasic]($(#2)+(\Angle+90:.3)$)arc[EndRotA];}
			}
		}
	\IfNoValueTF{#8}
		{\draw[RotBasic]($(#3)+(\Angle-90:.3)$)arc[EndRotB];}
		{\IfStrEq{\convention}{sign}
			{\node[fill=none,\rotColor]at($(#3)+(\Angle-90:.6)$){\footnotesize$#8$};\draw[RotBasic]($(#3)+(\Angle-90:.3)$)arc[EndRotB];}
			{\StrLeft{#8}{1}[\SS]\IfStrEq{\SS}{-}
				{\node[fill=none,\rotColor]at($(#3)+(\Angle+90:.6)$){\footnotesize$\StrDel[1]{#8}{-}$};\draw[RotBasic]($(#3)+(\Angle+90:.3)$)arc[EndRotD];}
				{\node[fill=none,\rotColor]at($(#3)+(\Angle-90:.6)$){\footnotesize$#8$};\draw[RotBasic]($(#3)+(\Angle-90:.3)$)arc[EndRotB];}
			}
		}
	}
	{}
}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%     Command 3: Hinge support
% \HingeSupport[1]{2}{3}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\NewDocumentCommand{\HingeSupport}{O{0} m G{1}}{
\begin{scope}[rotate around={#1:(#2)},shift={(#2)},scale=#3]
\draw[line width=.2mm](0,0)--++(-.25,-.4)--++(.5,0)--cycle;
\draw[line width=.2mm,FIXED](-.4,-.4)--++(.8,0);
\end{scope}
}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%     Command 4: UDL
% \UDL[1]{2}{3}[4]{5}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\makeatletter
\NewDocumentCommand{\UDL}{O{N} m m O{} G{1}}{
\IfEq{#1}{F}{\def\FAC{-1}}{\def\FAC{1}}
\coordinate(A)at(#2);
\coordinate(B)at(#3);
\pgfmathanglebetweenpoints{\pgfpointanchor{A}{center}}{\pgfpointanchor{B}{center}}
\let\Angle\pgfmathresult
\pgfpointdiff{\pgfpointanchor{A}{center}}{\pgfpointanchor{B}{center}}
\pgfmathparse{veclen(\pgf@x,\pgf@y)/28.45274}
\let\Length\pgfmathresult
\draw[\fillColor,fill=\fillColor,fill opacity=.4](#2)--(#3)--($(#3)+(\Angle+\FAC*90:\Length/10*#5)$)--($(#2)+(\Angle+\FAC*90:\Length/10*#5)$)--cycle;
\IfNoValueTF{#4}
	{}
	{\IfStrEq{\convention}{sign}
		{\node[NOFILL]at($(#2)!.5!(#3)+(\Angle+\FAC*90:\Length/5*#5)$)[rotate=\Angle]{$#4$};}
		{\StrLeft{#4}{1}[\SS]\IfStrEq{\SS}{-}
			{\node[NOFILL]at($(#2)!.5!(#3)+(\Angle+\FAC*90:\Length/5*#5)$)[rotate=\Angle]{$\StrDel[1]{#4}{-}$};}
			{\node[NOFILL]at($(#2)!.5!(#3)+(\Angle+\FAC*90:\Length/5*#5)$)[rotate=\Angle]{$#4$};}
		}
	}
\foreach\x in{0,.1,.2,...,1}{
\coordinate(C)at($(#2)!\x!(#3)$);
\IfNoValueTF{#4}
	{\draw[<-](C)--++($(\Angle+\FAC*90:\Length/10*#5)$);}
	{\IfStrEq{\convention}{sign}
		{\draw[<-](C)--++($(\Angle+\FAC*90:\Length/10*#5)$);}
		{\StrLeft{#4}{1}[\SS]\IfStrEq{\SS}{-}
			{\draw[->](C)--++($(\Angle+\FAC*90:\Length/10*#5)$);}
			{\draw[<-](C)--++($(\Angle+\FAC*90:\Length/10*#5)$);}
		}
	}
};
}
\makeatother
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%     Command 5: Fixed support
% \FixedSupport[1]{2}{3}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\NewDocumentCommand{\FixedSupport}{O{0} m G{1}}{
\begin{scope}[rotate around={#1:(#2)},shift={(#2)},scale=#3]
\draw[line width=.2mm,FIXED](-.4,0)--++(.8,0);
\end{scope}
}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%     Command 6: Roller support
% \RollerSupport[1]{2}{3}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\NewDocumentCommand{\RollerSupport}{O{0} m G{1}}{
\begin{scope}[rotate around={#1:(#2)},shift={(#2)},scale=#3]
\draw[line width=.2mm]
	(0,0)--++(-.25,-.3)--++(.5,0)--cycle
	(-.15,-.35)circle(.05)
	(+.15,-.35)circle(.05);
\draw[line width=.2mm,FIXED]
	(-.4,-.4)--++(.8,0);
\end{scope}
}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%     Command 7: Slider support
% \SliderSupport[1]{2}{3}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\NewDocumentCommand{\SliderSupport}{O{0} m G{1}}{
\begin{scope}[rotate around={#1:(#2)},shift={(#2)},scale=#3]
\draw[line width=.2mm]
	(-.25,-.1/#3)--++(.5,0)
	(-.15,-.14/#3)--++(0,-.22)
	(+.15,-.14/#3)--++(0,-.22);
\draw[line width=.2mm,fill=white]
	(-.15,-.14/#3)circle(.04)++(0,-.22)circle(.04)
	(+.15,-.14/#3)circle(.04)++(0,-.22)circle(.04);
\draw[line width=.2mm,FIXED]
	(-.4,-.14/#3-.26)--++(.8,0);
\end{scope}
}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%     Command 8: Sleeve support
% \SleeveSupport[1]{2}{3}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\NewDocumentCommand{\SleeveSupport}{O{0} m O{.4} G{1}}{
\begin{scope}[rotate around={#1:(#2)},shift={(#2)},scale=#4]
\draw[line width=.2mm,FIXED](#3/2,-.4)--++(0,.8);
\draw[line width=.2mm,FIXED](-#3/2,.4)--++(0,-.8);
\end{scope}
}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%     Command 9: Coordinate system frame
% \CoorOrigin[1]{2}{3}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\NewDocumentCommand{\CoorOrigin}{O{0} m G{1}}{
\begin{scope}[rotate around={#1:(#2)},shift={(#2)},scale=#3]
\draw[line width=.2mm,->](-.2,0)--++(1,0);\node[fill=none,draw=none]at(1.1,0){\footnotesize$x$};
\draw[line width=.2mm,->](0,-.2)--++(0,1);\node[fill=none,draw=none]at(0,1.1){\footnotesize$y$};
\end{scope}
}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%     Command 10: Rigid constraint
% \Rigid[1]{2}{3}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\NewDocumentCommand{\Rigid}{O{0} m G{1}}{
\begin{scope}[rotate around={#1:(#2)},shift={(#2)},scale=#3]
\draw[fill=black,rounded corners=.2mm](0,0)--(.25,.4)--(.4,.25)--cycle;
\end{scope}
}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%     Command 11: Linear Internal Force
% \IForceA[1]{2}{3}{4}{5}{6}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\makeatletter
\NewDocumentCommand{\IForceA}{O{\fillColor} m m m m G{1}}{
\coordinate(A)at(#2);
\coordinate(B)at(#3);
\pgfmathanglebetweenpoints{\pgfpointanchor{A}{center}}{\pgfpointanchor{B}{center}}
\let\Angle\pgfmathresult
\coordinate(C)at($(A)+(\Angle+90:#4*#6)$);
\coordinate(D)at($(B)+(\Angle-90:#5*#6)$);
\draw[#1,fill=#1,fill opacity=.3](A)--(C)--(D)--(B)--cycle;
\pgfpointdiff{\pgfpointanchor{A}{center}}{\pgfpointanchor{B}{center}}
\pgfmathparse{veclen(\pgf@x,\pgf@y)/28.45274}
\let\Length\pgfmathresult
\StrLeft{#4}{1}[\SA]
\IfStrEq{\SA}{-}
	{\node[NOFILL]at($(C)+(\Angle-90:\Length/8)$)[rotate=\Angle]{$#4$};}
	{\node[NOFILL]at($(C)+(\Angle+90:\Length/8)$)[rotate=\Angle]{$#4$};}
\StrLeft{#5}{1}[\SB]
\IfStrEq{\SB}{-}
	{\node[NOFILL]at($(D)+(\Angle+90:\Length/8)$)[rotate=\Angle]{$#5$};}
	{\node[NOFILL]at($(D)+(\Angle-90:\Length/8)$)[rotate=\Angle]{$#5$};}
}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%     Command 12: Parabolic Internal Force
% \IForceB[1]{2}{3}{4}{5}{6}{7}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\NewDocumentCommand{\IForceB}{O{\fillColor} m m m m m G{1}}{
\coordinate(A)at(#2);
\coordinate(B)at(#3);
% original cord
\pgfmathanglebetweenpoints{\pgfpointanchor{A}{center}}{\pgfpointanchor{B}{center}}
\let\Angle\pgfmathresult
\coordinate(C)at($(A)+(\Angle+90:#4*#7)$);
\coordinate(D)at($(B)+(\Angle-90:#5*#7)$);
% shape cord
\pgfmathanglebetweenpoints{\pgfpointanchor{C}{center}}{\pgfpointanchor{D}{center}}
\let\AngleB\pgfmathresult
% original length
\pgfpointdiff{\pgfpointanchor{A}{center}}{\pgfpointanchor{B}{center}}
\pgfmathparse{veclen(\pgf@x,\pgf@y)/28.45274}
\let\Length\pgfmathresult
% inclined length
\pgfpointdiff{\pgfpointanchor{C}{center}}{\pgfpointanchor{D}{center}}
\pgfmathparse{veclen(\pgf@x,\pgf@y)/28.45274}
\let\LengthB\pgfmathresult
% center of inclined cord
\coordinate(G)at($(C)+(\AngleB:\LengthB/2)$);
\pgfmathsetmacro\height{#6*#7};
\begin{scope}[rotate around={\AngleB:(G)},shift={(G)}]
\draw[#1,fill=#1,fill opacity=.3](-.5*\LengthB,0)parabola bend(0,\height)(.5*\LengthB,0)--++(\Angle-\AngleB+90:#5*#7)--($(-.5*\LengthB,0)+(\Angle-\AngleB-90:#4*#7)$)--cycle;
\end{scope}

\StrLeft{#4}{1}[\SA]
\IfStrEq{\SA}{-}
	{\node[NOFILL]at($(C)+(\Angle-90:\Length/8)$)[rotate=\Angle]{$#4$};}
	{\node[NOFILL]at($(C)+(\Angle+90:\Length/8)$)[rotate=\Angle]{$#4$};}
\StrLeft{#5}{1}[\SB]
\IfStrEq{\SB}{-}
	{\node[NOFILL]at($(D)+(\Angle+90:\Length/8)$)[rotate=\Angle]{$#5$};}
	{\node[NOFILL]at($(D)+(\Angle-90:\Length/8)$)[rotate=\Angle]{$#5$};}
}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%     Command 13: Beam Deformation (perpendicular)
% \BeamDeformP[1]{2}{3}{4}[5]{6}[7]{8}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\NewDocumentCommand{\BeamDeformP}{O{\fillColor} m m m O{0} m O{0} G{1}}{
\coordinate(A)at(#2);
\coordinate(B)at(#3);
% original cord
\pgfmathanglebetweenpoints{\pgfpointanchor{A}{center}}{\pgfpointanchor{B}{center}}
\let\Angle\pgfmathresult
\coordinate(C)at($(A)+(\Angle+90:#4*#8)$);
\coordinate(D)at($(B)+(\Angle-90:#6*#8)$);
\pgfmathanglebetweenpoints{\pgfpointanchor{C}{center}}{\pgfpointanchor{D}{center}}
\let\AngleB\pgfmathresult
\draw[#1,line width=.8mm](C)to[out=\AngleB+#5*#8,in=180+\AngleB+#7*#8](D);
}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%     Command 13: Beam Deformation (Rotation Only)
% \BeamDeformR[1]{2}{3}[4][5]{6}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\NewDocumentCommand{\BeamDeformR}{O{\fillColor} m m O{0} O{0} G{1}}{
\coordinate(A)at(#2);
\coordinate(B)at(#3);
% original cord
\pgfmathanglebetweenpoints{\pgfpointanchor{A}{center}}{\pgfpointanchor{B}{center}}
\let\Angle\pgfmathresult
\draw[#1,line width=.8mm](A)to[out=\Angle+#4*#6,in=180+\Angle+#5*#6](B);
}
\makeatother