Fix sorting of intersections #480

CAVEAT: Breaking change! The order of intersection will change if you are using the \pgfintersectionsortby... commands or the "sort by=" key in TikZ.
pgf-tikz · Nov 29, 2019 · acd2ca3 · acd2ca3
1 parent 0092d3a
commit acd2ca3
Showing 1 changed file with 8 additions and 1 deletion.
diff --git a/tex/generic/pgf/libraries/pgflibraryintersections.code.tex b/tex/generic/pgf/libraries/pgflibraryintersections.code.tex
@@ -361,23 +361,30 @@
             \global\advance\pgf@intersect@solutions by1\relax%
             \expandafter\global\expandafter\let\csname pgfpoint@g@intersect@solution@\the\pgf@intersect@solutions\endcsname=\pgf@intersect@solution@candidate
             \ifpgf@intersect@sort%
+                % save coordinates of the intersection
+                \pgf@process{\pgf@intersect@solution@candidate}%
                 \pgf@xc=\pgf@x%
                 \pgf@yc=\pgf@y%
+                % determine length of path
                 \pgf@process{\pgfpointdiff{\pgfpoint@intersect@start@a}{\pgfpoint@intersect@end@a}}%
                 \edef\pgf@marshal{%
-                    \noexpand\pgfmathveclen@{\pgfmath@tonumber{\pgf@xa}}{\pgfmath@tonumber{\pgf@ya}}%
+                    \noexpand\pgfmathveclen@{\pgfmath@tonumber{\pgf@x}}{\pgfmath@tonumber{\pgf@y}}%
                 }%
                 \pgf@marshal%
                 \let\pgf@intersect@length@a=\pgfmathresult%
+                % determine distance of intersection from start
                 \pgf@process{\pgfpointdiff{\pgfpoint@intersect@start@a}{\pgfqpoint{\pgf@xc}{\pgf@yc}}}%
                 \edef\pgf@marshal{%
                     \noexpand\pgfmathveclen@{\pgfmath@tonumber{\pgf@x}}{\pgfmath@tonumber{\pgf@y}}%
                 }%
                 \pgf@marshal%
+                % scale the distance to the path length (path time)
                 \pgfmathdivide@{\pgfmathresult}{\pgf@intersect@length@a}%
                 \pgf@x=\pgfmathresult pt\relax%
+                % advance by the path segment (see definition of \pgf@intersection@store@properties)
                 \advance\pgf@x by\pgf@intersect@time@offset pt\relax%
                 \edef\pgf@intersect@time@a{\pgfmath@tonumber{\pgf@x}}%
+                % save numbered
                 \expandafter\global\expandafter\let\csname pgf@g@intersect@solution@\the\pgf@intersect@solutions @time@a\endcsname=
                     \pgf@intersect@time@a
             \else