[intersections] "Sort by" resulting in wrong order of intersections

[pgf-tikz-bot]

Migrated from SourceForge
Author: icyd
Timestamp: 2018-05-02 09:51:08.169000

Using the following MWE, the direction of the blue arrow is opposite to the black one:

\documentclass{standalone}    
\usepackage{tikz}  
\usetikzlibrary{intersections}
\begin{document}  
\begin{tikzpicture}
    \draw [name path=base] (-1,-1) rectangle (1,1);
    \draw [->, name path=line] (0.5,-2) -- (1.8,2);
    \draw [color=blue, thick, ->, name intersections={of=line and base, sort by=line}] (intersection-1) -- (intersection-2);
\end{tikzpicture}  
\end{document}

[hmenke]

Pure PGF reproducer.

\documentclass{standalone}    
\usepackage{tikz}  
\usepgflibrary{intersections}
\begin{document}  
\begin{pgfpicture}
  \pgfpathrectangle{\pgfqpoint{-1cm}{-1cm}}{\pgfqpoint{2cm}{2cm}}
  \pgfusepath{stroke}
  \pgfsetarrowsend{>}
  \pgfpathmoveto{\pgfqpoint{0.5cm}{-2cm}}
  \pgfpathlineto{\pgfqpoint{1.8cm}{2cm}}
  \pgfusepath{stroke}

  \pgfintersectionsortbyfirstpath
  \pgfintersectionofpaths{
    \pgfpathmoveto{\pgfqpoint{0.5cm}{-2cm}}
    \pgfpathlineto{\pgfqpoint{1.8cm}{2cm}}
  }{
    \pgfpathrectangle{\pgfqpoint{-1cm}{-1cm}}{\pgfqpoint{2cm}{2cm}}
  }

  \color{blue}
  \pgfsetarrowsend{>}
  \pgfpathmoveto{\pgfpointintersectionsolution{1}}
  \pgfpathlineto{\pgfpointintersectionsolution{2}}
  \pgfusepath{stroke}
\end{pgfpicture}  
\end{document}