%
% CoDi: Commutative Diagrams for TeX
% Copyright (c) 2015-2024 Paolo Brasolin <
[email protected]>
% SPDX-License-Identifier: MIT
%
% This file is part of CoDi 1.1.2, released on 2024/04/22 under MIT license.
%
% διορθώνω • (diorthóno)
% 1. I correct
% 2. I mend
% 3. I repair
% Diorthono is a collection of bugfixes.
% Save catcode of @ to restore it at EOF.
\edef\kDAct{\catcode`@=\the\catcode`@\relax}
\catcode`@=11\relax
% The following code patches \pgfpathcurvebetweentime.
% See
http://tex.stackexchange.com/a/271024/82186 for reference.
% Original fix by Mark Wibrow.
\def\pgf@@pathcurvebetweentime#1#2#3#4#5#6{%
\pgfmathparse{#1}%
\let\pgf@time@s=\pgfmathresult%
\pgfmathparse{#2}%
\let\pgf@time@t=\pgfmathresult%
\ifdim\pgf@time@s pt>\pgf@time@t pt\relax%
\pgfmathsetmacro\pgf@time@s{1-#1}%
\pgfmathsetmacro\pgf@time@t{1-#2}%
\pgf@@@pathcurvebetweentime{#6}{#5}{#4}{#3}%
\else%
\pgf@@@pathcurvebetweentime{#3}{#4}{#5}{#6}%
\fi%
}
\def\pgf@@@pathcurvebetweentime#1#2#3#4{%
\begingroup%
% Get the curve Q from curve P for time 0 to t
\pgfextract@process\Pa{#1}%
\pgfextract@process\Pb{#2}%
\pgfextract@process\Pc{#3}%
\pgfextract@process\Pd{#4}%
% Qa = Pa
\pgfextract@process\Qa{\Pa}%
% Qb = Pa + t*(Pb-Pa).
\pgfextract@process\Qb{%
\pgfpointadd{\Pa}{\pgfpointscale{\pgf@time@t}{\pgfpointdiff{\Pa}{\Pb}}}%
}%
% Qc = Qb + t*((Pb + t*(Pc-Pb)) - Qb)
\pgfextract@process\Qc{%
\pgfpointadd{\Qb}{\pgfpointscale{\pgf@time@t}{\pgfpointdiff{\Qb}{\pgfpointadd{\Pb}{\pgfpointscale{\pgf@time@t}{\pgfpointdiff{\Pb}{\Pc}}}}}}%
}%
% Qd = (1-t)^3*Pa + 3*t(1-t)^2*Pb + 3*t^2(1-t)*Pc + t^3*Pd.
\pgfextract@process\Qd{\pgfpointcurveattime{\pgf@time@t}{\Pa}{\Pb}{\Pc}{\Pd}}%
%
% Now get the curve R from the reversed curve Q for time 0 to 1-s/t
\pgfmathdivide@{\pgf@time@s}{\pgf@time@t}%
\pgfmathadd@{-\pgfmathresult}{1.0}%
\let\pgf@time@s=\pgfmathresult%
% Rd = Qd
\pgfextract@process\Rd{\Qd}%
% Rc = Qd + s*(Qc-Qd).
\pgfextract@process\Rc{%
\pgfpointadd{\Qd}{\pgfpointscale{\pgf@time@s}{\pgfpointdiff{\Qd}{\Qc}}}%
}%
% Rb = Rc + s*((Qc + s*(Qb-Qc)) - Rc)
\pgfextract@process\Rb{%
\pgfpointadd{\Rc}{\pgfpointscale{\pgf@time@s}{\pgfpointdiff{\Rc}{\pgfpointadd{\Qc}{\pgfpointscale{\pgf@time@s}{\pgfpointdiff{\Qc}{\Qb}}}}}}%
}%
% Ra = (1-s)^3*Qd + 3*s(1-s)^2*Qc + 3*s^2(1-s)*Qb + s^3*Qa.
\pgfextract@process\Ra{\pgfpointcurveattime{\pgf@time@s}{\Qd}{\Qc}{\Qb}{\Qa}}%
\ifpgf@ignoremoveto\else\pgfpathmoveto{\Ra}\fi%
\pgfpathcurveto{\Rb}{\Rc}{\Rd}%
\endgroup%
}
% Restore catcode of @.
\kDAct
