1 files changed, 139 insertions, 0 deletions
diff --git a/share/extensions/pdflatex.py b/share/extensions/pdflatex.py
new file mode 100755
index 0000000..f989191
--- /dev/null
+++ b/share/extensions/pdflatex.py
@@ -0,0 +1,139 @@
+#!/usr/bin/env python
+# coding=utf-8
+#
+# Copyright (C) 2019 Marc Jeanmougin
+#
+# 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 2 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, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
+#
+"""
+Generate Latex via a PDF using pdflatex
+"""
+
+import os
+
+import inkex
+from inkex.base import TempDirMixin
+from inkex.command import ProgramRunError, call, inkscape
+from inkex import load_svg, ShapeElement, Defs
+from inkex.units import convert_unit
+from inkex.localization import inkex_gettext as _
+
+
+class PdfLatex(TempDirMixin, inkex.GenerateExtension):
+    """
+    Use pdflatex to generate LaTeX, this whole hack is required because
+    we don't want to open a LaTeX document as a document, but as a
+    generated fragment (like import, but done manually).
+    """
+
+    def add_arguments(self, pars):
+        pars.add_argument(
+            "--formule",
+            type=str,
+            default=r"\(\displaystyle\frac{\pi^2}{6}=\lim_{n \to \infty}\sum_{k=1}^n \frac{1}{k^2}\)",
+        )
+        pars.add_argument(
+            "--preamble",
+            type=str,
+            default="".join(
+                f"\\usepackage{{ams{i}}}" for i in ["math", "symb", "fonts"]
+            ),
+        )
+        pars.add_argument("--font_size", type=int, default=10)
+        pars.add_argument("--page", choices=["basic", "advanced"])
+        pars.add_argument("--standalone", type=inkex.Boolean, default=True)
+
+    def generate(self):
+        tex_file = os.path.join(self.tempdir, "input.tex")
+        pdf_file = os.path.join(self.tempdir, "input.pdf")  # Auto-generate by pdflatex
+        svg_file = os.path.join(self.tempdir, "output.svg")
+
+        with open(tex_file, "w") as fhl:
+            self.write_latex(fhl)
+
+        try:
+            call(
+                "pdflatex",
+                tex_file,
+                output_directory=self.tempdir,
+                halt_on_error=True,
+                oldie=True,
+            )
+        except ProgramRunError as err:
+            inkex.errormsg(_("An exception occurred during LaTeX compilation: ") + "\n")
+            inkex.errormsg(err.stdout.decode("utf8").replace("\r\n", "\n"))
+            raise inkex.AbortExtension()
+
+        inkscape(
+            pdf_file,
+            export_filename=svg_file,
+            pdf_page=1,
+            pdf_poppler=True,
+            export_type="svg",
+            actions=(
+                "select-all;page-fit-to-selection;"
+                "clone-unlink-recursively;vacuum-defs"
+            ),
+        )
+
+        if not os.path.isfile(svg_file):
+            fn = os.path.basename(svg_file)
+            if os.path.isfile(fn):
+                # Inkscape bug detected, file got saved wrong
+                svg_file = fn
+
+        with open(svg_file, "r") as fhl:
+            svg: inkex.SvgDocumentElement = load_svg(fhl).getroot()
+
+            scale = convert_unit("1pt", "px") / self.svg.scale
+            if not self.options.standalone:
+                scale *= self.options.font_size / 10
+
+            for child in svg:
+                if isinstance(child, ShapeElement):
+                    child.transform = inkex.Transform(scale=scale) @ child.transform
+                    yield child
+                elif isinstance(child, Defs):
+                    for def_child in child:
+                        # The ids of both the imported and the target document should
+                        # be off-limits
+                        def_child.set_random_ids(
+                            backlinks=True, blacklist=self.svg.get_ids()
+                        )
+                        self.svg.defs.append(def_child)
+
+    def write_latex(self, stream):
+        """Takes a formula and wraps it in latex"""
+        if self.options.standalone:
+            docclass = (
+                f"\\documentclass[fontsize={self.options.font_size}pt, "
+                + "class=scrreprt, preview]{standalone}"
+            )
+        else:
+            docclass = r"\documentclass{minimal}"
+        stream.write(
+            f"""%% processed with pdflatex.py
+{docclass}
+{self.options.preamble}
+\\begin{{document}}
+{self.options.formule}
+\\end{{document}}
+"""
+        )
+        stream.flush()
+
+
+if __name__ == "__main__":
+    PdfLatex().run()