Add new file rebased away during cleanup of previous patchset

boxes/svgutil.py

@@ -0,0 +1,91 @@
+#!/usr/bin/python3
+# Copyright (C) 2016 Florian Festi
+#
+#   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 3 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, see <http://www.gnu.org/licenses/>.
+
+import xml.parsers.expat
+import re
+
+class SVGFile(object):
+
+    pathre = re.compile(r"[MCL]? *((-?\d+\.\d+) (-?\d+\.\d+) *)+")
+    transformre = re.compile(r"matrix\(" + ",".join([r"(-?\d+(\.\d+)?)"] * 6) + "\)")
+
+    def __init__(self, filename):
+        self.filename = filename
+        self.minx = self.maxx = self.miny = self.maxy = None
+
+    def handleStartElement(self, name, attrs):
+        self.tags.append(name)
+        if name == "path" and "symbol" not in self.tags:
+            minx = maxx = miny = maxy = None
+            m = self.transformre.match(attrs.get("transform", ""))
+            if m:
+                matrix = [float(m.group(i)) for i in range(1, 12, 2)]
+            else:
+                matrix = [1,0,0,
+                          0,1,0]
+            for m in self.pathre.findall(attrs.get("d", "")):
+                x = float(m[1])
+                y = float(m[2])
+                tx = matrix[0]*x+matrix[2]*y+matrix[4]
+                ty = matrix[1]*x+matrix[3]*y+matrix[5]
+
+                if self.minx is None or self.minx > tx:
+                    self.minx = tx
+                if self.maxx is None or self.maxx < tx:
+                    self.maxx = tx
+                if self.miny is None or self.miny > ty:
+                    self.miny = ty
+                if self.maxy is None or self.maxy < ty:
+                    self.maxy = ty
+
+    def handleEndElement(self, name):
+        last = self.tags.pop()
+        if last != name:
+            raise ValueError("Got </%s> expected </%s>" % (name, last))
+
+    def getEnvelope(self):
+        self.tags = []
+        p = xml.parsers.expat.ParserCreate()
+        p.StartElementHandler = self.handleStartElement
+        p.EndElementHandler = self.handleEndElement
+        p.ParseFile(open(self.filename, "rb"))
+
+    def rewriteViewPort(self):
+        f = open(self.filename, "r+")
+        s = f.read(1024)
+
+        m = re.search(r"""<svg[^>]*width="(\d+pt)" height="(\d+pt)" viewBox="0 (0 (\d+) (\d+))" version="1.1">""", s)
+
+        minx = 10*int(self.minx//10)-10
+        maxx = 10*int(self.maxx//10)+10
+        miny = 10*int(self.miny//10)-10
+        maxy = 10*int(self.maxy//10)+10
+
+        if m:
+            f.seek(m.start(1))
+            f.write("%4imm" % (maxx-minx))
+            f.seek(m.start(2))
+            f.write("%4imm" % (maxy-miny))
+            f.seek(m.start(3))
+            f.write("%3i %3i %3i" % (miny, maxx, maxy-miny))
+        else:
+            raiseValueError("Could not understand SVG file")
+        
+
+if __name__ == "__main__":
+    svg = SVGFile("examples/box.svg")
+    svg.getEnvelope()
+    svg.rewriteViewPort()