Basic Svg_Io_Sax (#66)

* Basic Svg_Io_Sax

* Update to binary write

* Fixed SaxSvg Load, tweaked test.

* Couple tweaks.

* Couple tweaks to fit the dom parser api better

* Switch to iterparse for speed

* Used None matrix for identity in default case.

* Test Update for None Matrix

svgpathtools/__init__.py

@@ -13,6 +13,7 @@ from .polytools import polyroots, polyroots01, rational_limit, real, imag
 from .misctools import hex2rgb, rgb2hex
 from .smoothing import smoothed_path, smoothed_joint, is_differentiable, kinks
 from .document import Document, CONVERSIONS, CONVERT_ONLY_PATHS, SVG_GROUP_TAG, SVG_NAMESPACE
+from .svg_io_sax import SaxDocument
 
 try:
     from .svg_to_paths import svg2paths, svg2paths2

svgpathtools/svg_io_sax.py

@@ -0,0 +1,198 @@
+"""(Experimental) replacement for import/export functionality SAX
+
+"""
+
+# External dependencies
+from __future__ import division, absolute_import, print_function
+import os
+from xml.etree.ElementTree import iterparse, Element, ElementTree, SubElement
+
+# Internal dependencies
+from .parser import parse_path
+from .parser import parse_transform
+from .svg_to_paths import (path2pathd, ellipse2pathd, line2pathd,
+                           polyline2pathd, polygon2pathd, rect2pathd)
+from .misctools import open_in_browser
+from .path import *
+
+# To maintain forward/backward compatibility
+try:
+    str = basestring
+except NameError:
+    pass
+
+NAME_SVG = "svg"
+ATTR_VERSION = "version"
+VALUE_SVG_VERSION = "1.1"
+ATTR_XMLNS = "xmlns"
+VALUE_XMLNS = "http://www.w3.org/2000/svg"
+ATTR_XMLNS_LINK = "xmlns:xlink"
+VALUE_XLINK = "http://www.w3.org/1999/xlink"
+ATTR_XMLNS_EV = "xmlns:ev"
+VALUE_XMLNS_EV = "http://www.w3.org/2001/xml-events"
+ATTR_WIDTH = "width"
+ATTR_HEIGHT = "height"
+ATTR_VIEWBOX = "viewBox"
+NAME_PATH = "path"
+ATTR_DATA = "d"
+ATTR_FILL = "fill"
+ATTR_STROKE = "stroke"
+ATTR_STROKE_WIDTH = "stroke-width"
+ATTR_TRANSFORM = "transform"
+VALUE_NONE = "none"
+
+
+class SaxDocument:
+    def __init__(self, filename):
+        """A container for a SAX SVG light tree objects document.
+
+        This class provides functions for extracting SVG data into Path objects.
+
+        Args:
+            filename (str): The filename of the SVG file
+        """
+        self.root_values = {}
+        self.tree = []
+        # remember location of original svg file
+        if filename is not None and os.path.dirname(filename) == '':
+            self.original_filename = os.path.join(os.getcwd(), filename)
+        else:
+            self.original_filename = filename
+
+        if filename is not None:
+            self.sax_parse(filename)
+
+    def sax_parse(self, filename):
+        self.root_values = {}
+        self.tree = []
+        stack = []
+        values = {}
+        matrix = None
+        for event, elem in iterparse(filename, events=('start', 'end')):
+            if event == 'start':
+                stack.append((values, matrix))
+                if matrix is not None:
+                    matrix = matrix.copy()  # copy of matrix
+                current_values = values
+                values = {}
+                values.update(current_values)  # copy of dictionary
+                attrs = elem.attrib
+                values.update(attrs)
+                name = elem.tag[28:]
+                if "style" in attrs:
+                    for equate in attrs["style"].split(";"):
+                        equal_item = equate.split(":")
+                        values[equal_item[0]] = equal_item[1]
+                if "transform" in attrs:
+                    transform_matrix = parse_transform(attrs["transform"])
+                    if matrix is None:
+                        matrix = np.identity(3)
+                    matrix = transform_matrix.dot(matrix)
+                if "svg" == name:
+                    current_values = values
+                    values = {}
+                    values.update(current_values)
+                    self.root_values = current_values
+                    continue
+                elif "g" == name:
+                    continue
+                elif 'path' == name:
+                    values['d'] = path2pathd(values)
+                elif 'circle' == name:
+                    values["d"] = ellipse2pathd(values)
+                elif 'ellipse' == name:
+                    values["d"] = ellipse2pathd(values)
+                elif 'line' == name:
+                    values["d"] = line2pathd(values)
+                elif 'polyline' == name:
+                    values["d"] = polyline2pathd(values['points'])
+                elif 'polygon' == name:
+                    values["d"] = polygon2pathd(values['points'])
+                elif 'rect' == name:
+                    values["d"] = rect2pathd(values)
+                else:
+                    continue
+                values["matrix"] = matrix
+                values["name"] = name
+                self.tree.append(values)
+            else:
+                v = stack.pop()
+                values = v[0]
+                matrix = v[1]
+
+    def flatten_all_paths(self):
+        flat = []
+        for values in self.tree:
+            pathd = values['d']
+            matrix = values['matrix']
+            parsed_path = parse_path(pathd)
+            if matrix is not None:
+                transform(parsed_path, matrix)
+            flat.append(parsed_path)
+        return flat
+
+    def get_pathd_and_matrix(self):
+        flat = []
+        for values in self.tree:
+            pathd = values['d']
+            matrix = values['matrix']
+            flat.append((pathd, matrix))
+        return flat
+
+    def generate_dom(self):
+        root = Element(NAME_SVG)
+        root.set(ATTR_VERSION, VALUE_SVG_VERSION)
+        root.set(ATTR_XMLNS, VALUE_XMLNS)
+        root.set(ATTR_XMLNS_LINK, VALUE_XLINK)
+        root.set(ATTR_XMLNS_EV, VALUE_XMLNS_EV)
+        width = self.root_values.get(ATTR_WIDTH, None)
+        height = self.root_values.get(ATTR_HEIGHT, None)
+        if width is not None:
+            root.set(ATTR_WIDTH, width)
+        if height is not None:
+            root.set(ATTR_HEIGHT, height)
+        viewbox = self.root_values.get(ATTR_VIEWBOX, None)
+        if viewbox is not None:
+            root.set(ATTR_VIEWBOX, viewbox)
+        identity = np.identity(3)
+        for values in self.tree:
+            pathd = values.get('d', '')
+            matrix = values.get('matrix', None)
+            # path_value = parse_path(pathd)
+
+            path = SubElement(root, NAME_PATH)
+            if matrix is not None and not np.all(np.equal(matrix, identity)):
+                matrix_string = "matrix("
+                matrix_string += " "
+                matrix_string += str(matrix[0][0])
+                matrix_string += " "
+                matrix_string += str(matrix[1][0])
+                matrix_string += " "
+                matrix_string += str(matrix[0][1])
+                matrix_string += " "
+                matrix_string += str(matrix[1][1])
+                matrix_string += " "
+                matrix_string += str(matrix[0][2])
+                matrix_string += " "
+                matrix_string += str(matrix[1][2])
+                matrix_string += ")"
+                path.set(ATTR_TRANSFORM, matrix_string)
+            if ATTR_DATA in values:
+                path.set(ATTR_DATA, values[ATTR_DATA])
+            if ATTR_FILL in values:
+                path.set(ATTR_FILL, values[ATTR_FILL])
+            if ATTR_STROKE in values:
+                path.set(ATTR_STROKE, values[ATTR_STROKE])
+        return ElementTree(root)
+
+    def save(self, filename):
+        with open(filename, 'wb') as output_svg:
+            dom_tree = self.generate_dom()
+            dom_tree.write(output_svg)
+
+    def display(self, filename=None):
+        """Displays/opens the doc using the OS's default application."""
+        if filename is None:
+            filename = 'display_temp.svg'
+        self.save(filename)
+        open_in_browser(filename)

test/display_temp.svg

@@ -0,0 +1 @@
+<svg height="100%" version="1.1" viewBox="0 0 365 365" width="100%" xmlns="http://www.w3.org/2000/svg" xmlns:ev="http://www.w3.org/2001/xml-events" xmlns:xlink="http://www.w3.org/1999/xlink"><path d="M10.0,50.0a40.0,40.0 0 1,0 80.0,0a40.0,40.0 0 1,0 -80.0,0" fill="red" stroke="black" transform="matrix( 1.5 0.0 0.0 0.5 -40.0 20.0)" /><path d="M 150,200 l -50,25" fill="black" stroke="black" transform="matrix( 1.5 0.0 0.0 0.5 -40.0 20.0)" /><path d="M 100 350 l 150 -300" fill="none" stroke="red" /><path d="M 250 50 l 150 300" fill="none" stroke="red" /><path d="M 175 200 l 150 0" fill="none" stroke="green" /><path d="M 100 350 q 150 -300 300 0" fill="none" stroke="blue" /><path d="M97.0,350.0a3.0,3.0 0 1,0 6.0,0a3.0,3.0 0 1,0 -6.0,0" fill="black" stroke="black" /><path d="M247.0,50.0a3.0,3.0 0 1,0 6.0,0a3.0,3.0 0 1,0 -6.0,0" fill="black" stroke="black" /><path d="M397.0,350.0a3.0,3.0 0 1,0 6.0,0a3.0,3.0 0 1,0 -6.0,0" fill="black" stroke="black" /><path d="M200 10L250 190L160 210z" fill="lime" stroke="purple" transform="matrix( 0.1 0.0 0.0 0.1 0.0 0.0)" /></svg>

test/groups.svg

@@ -70,7 +70,8 @@
 
       <g
           id="nested group - translate xy"
-          transform="translate(20, 30)">
+          transform="
+          translate(20, 30)">
 
         <path
             d="M 150,200 l -50,25"

test/test_sax_groups.py

@@ -0,0 +1,30 @@
+from __future__ import division, absolute_import, print_function
+import unittest
+from svgpathtools import *
+from os.path import join, dirname
+import numpy as np
+
+
+class TestSaxGroups(unittest.TestCase):
+
+    def check_values(self, v, z):
+        # Check that the components of 2D vector v match the components
+        # of complex number z
+        self.assertAlmostEqual(v[0], z.real)
+        self.assertAlmostEqual(v[1], z.imag)
+
+    def test_parse_display(self):
+        doc = SaxDocument(join(dirname(__file__), 'transforms.svg'))
+        # doc.display()
+        for i, node in enumerate(doc.tree):
+            values = node
+            path_value = values['d']
+            matrix = values['matrix']
+            self.assertTrue(values is not None)
+            self.assertTrue(path_value is not None)
+            if i == 0:
+                self.assertEqual(values['fill'], 'red')
+            if i == 8 or i == 7:
+                self.assertEqual(matrix, None)
+            if i == 9:
+                self.assertEqual(values['fill'], 'lime')

test/transforms.svg

@@ -0,0 +1,49 @@
+<?xml version="1.0" ?>
+<svg
+    version="1.1"
+    viewBox="0 0 365 365"
+    height="100%"
+    width="100%"
+    xmlns="http://www.w3.org/2000/svg">
+  <g
+      id="matrix group"
+      transform="matrix(1.5 0.0 0.0 0.5 -40.0 20.0)" stroke="black" style="fill:red">
+	<circle cx="50" cy="50" r="40"  stroke-width="3"  />
+	<g id="scale group" transform="scale(1.25)"></g>
+
+      <g>
+        <path
+            d="M 150,200 l -50,25"
+            fill="black"
+            stroke="black"
+            stroke-width="3"
+            />
+      </g>
+  </g>
+  <path id="lineAB" d="M 100 350 l 150 -300" stroke="red"
+  stroke-width="3" fill="none" />
+  <path id="lineBC" d="M 250 50 l 150 300" stroke="red"
+  stroke-width="3" fill="none" />
+  <path d="M 175 200 l 150 0" stroke="green" stroke-width="3"
+  fill="none" />
+  <path d="M 100 350 q 150 -300 300 0" stroke="blue"
+  stroke-width="5" fill="none" />
+  <!-- Mark relevant points -->
+  <g stroke="black" stroke-width="3" fill="black">
+    <circle id="pointA" cx="100" cy="350" r="3" />
+    <circle id="pointB" cx="250" cy="50" r="3" />
+    <circle id="pointC" cx="400" cy="350" r="3" />
+  </g>
+  <!-- Label the points -->
+  <g font-size="30" font-family="sans-serif" fill="black" stroke="none"
+  text-anchor="middle">
+    <text x="100" y="350" dx="-30">A</text>
+    <text x="250" y="50" dy="-10">B</text>
+    <text x="400" y="350" dx="30">C</text>
+  </g>
+
+      <g transform="scale(0.1)">
+	<polygon points="200,10 250,190 160,210" style="fill:lime;stroke:purple;stroke-width:1" />
+      </g>
+
+</svg>