1 files changed, 97 insertions, 0 deletions
diff --git a/tex/context/modules/mkiv/m-gnuplot.mkxl b/tex/context/modules/mkiv/m-gnuplot.mkxl
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index 000000000..2077b1741
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+++ b/tex/context/modules/mkiv/m-gnuplot.mkxl
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+%D \module
+%D   [       file=m-gnuplot,
+%D        version=2020.02.10,
+%D          title=\CONTEXT\ Extra Modules,
+%D       subtitle=Gnuplot,
+%D         author=Hans Hagen,
+%D           date=\currentdate,
+%D      copyright={PRAGMA ADE \& \CONTEXT\ Development Team}]
+%C
+%C This module is part of the \CONTEXT\ macro||package and is
+%C therefore copyrighted by \PRAGMA. See mreadme.pdf for
+%C details.
+
+%D This is a variant on the \GNUPLOT\ terminal code. At some point (when there is a
+%D reason) I will make a proper environment that can be used for embedded code.
+
+\unexpanded\def\includegnuplotsvgfile[#1]%
+  {\hbox\bgroup
+     \ctxlua{metapost.startsvghashing()}%
+     \includesvgfile[#1]%
+     \ctxlua{metapost.stopsvghashing()}%
+   \egroup}
+
+\startluacode
+
+local modificationtime = lfs.modification
+local longtostring     = string.longtostring
+local formatters       = string.formatters
+local expandfilename   = dir.expandname
+local isfile           = lfs.isfile
+
+local runner = sandbox.registerrunner {
+    name     = "gnuplot to svg",
+    program  = "gnuplot",
+    template = longtostring [[
+        -e "set output '%newname%'; set terminal svg"
+        "%oldname%"
+    ]],
+    checkers = {
+        oldname = "readable",
+        newname = "writable",
+    },
+}
+
+figures.programs.gnuplot = {
+    runner = runner,
+}
+
+local function remap(specification)
+    local oldname = specification.fullname
+    if oldname then
+        local newname = file.replacesuffix(oldname,"svg")
+        local oldtime = modificationtime(oldname) or 0
+        local newtime = modificationtime(newname) or 0
+        if newtime == 0 or oldtime > newtime then
+            runner {
+                newname = expandfilename(newname),
+                oldname = expandfilename(oldname),
+            }
+        end
+        if isfile(newname) then
+            local only = file.nameonly(newname)
+            local name = formatters["svg-%s-inclusion"](only)
+            local code = formatters["\\includegnuplotsvgfile[%s]\\resetbuffer[%s]"](newname,name)
+            buffers.assign(name,code)
+            specification.format   = "buffer"
+            specification.fullname = name
+        end
+    end
+    return specification
+end
+
+figures.remappers.gp = { svg = remap }
+
+\stopluacode
+
+\continueifinputfile{m-gnuplot.mkxl}
+
+\startluacode
+io.savedata("m-gnuplot-demo.gp", [[
+set format xy "$%g$"
+
+set title  'This is a plot of $y=\\sin(x)$'
+set xlabel 'This is the $x$ axis'
+set ylabel 'This is the $y$ axis'
+
+plot [0:6.28] [0:1] sin(x)
+]])
+\stopluacode
+
+\starttext
+
+    \externalfigure[m-gnuplot-demo.gp][conversion=svg,width=4cm]
+
+    \externalfigure[m-gnuplot-demo.gp][conversion=svg,width=8cm]
+
+\stoptext