Upstream svgpathtools improvement - v2.1

svgpathtools/svg_to_paths.py

@@ -27,7 +27,7 @@ def path2pathd(path):
     return path.get('d', '')
 
 
-def ellipse2pathd(ellipse):
+def ellipse2pathd(ellipse, use_cubics=False):
     """converts the parameters from an ellipse or a circle to a string for a 
     Path object d-attribute"""
 
@@ -46,10 +46,32 @@ def ellipse2pathd(ellipse):
     cx = float(cx)
     cy = float(cy)
 
-    d = ''
-    d += 'M' + str(cx - rx) + ',' + str(cy)
-    d += 'a' + str(rx) + ',' + str(ry) + ' 0 1,0 ' + str(2 * rx) + ',0'
-    d += 'a' + str(rx) + ',' + str(ry) + ' 0 1,0 ' + str(-2 * rx) + ',0'
+    if use_cubics:
+        # Modified by NXP 2024, 2025
+        PATH_KAPPA = 0.552284
+        rxKappa = rx * PATH_KAPPA;
+        ryKappa = ry * PATH_KAPPA;
+
+        #According to the SVG specification (https://lists.w3.org/Archives/Public/www-archive/2005May/att-0005/SVGT12_Main.pdf),
+        #Section 9.4, "The 'ellipse' element": "The arc of an 'ellipse' element begins at the "3 o'clock" point on
+        #the radius and progresses towards the "9 o'clock". Therefore, the ellipse begins at the rightmost point
+        #and progresses clockwise.
+        d = ''
+        # Move to the rightmost point
+        d += 'M' + str(cx + rx) + ' ' + str(cy)
+        # Draw bottom-right quadrant
+        d += 'C' + str(cx + rx) + ' ' + str(cy + ryKappa) + ' ' + str(cx + rxKappa) + ' ' + str(cy + ry) + ' ' + str(cx) + ' ' + str(cy + ry)
+        # Draw bottom-left quadrant
+        d += 'C' + str(cx - rxKappa) + ' ' + str(cy + ry) + ' ' + str(cx - rx) + ' ' + str(cy + ryKappa) + ' ' + str(cx - rx) + ' ' + str(cy)
+        # Draw top-left quadrant
+        d += 'C' + str(cx - rx) + ' ' + str(cy - ryKappa) + ' ' + str(cx - rxKappa) + ' ' + str(cy - ry) + ' ' + str(cx) + ' ' + str(cy - ry)
+        # Draw top-right quadrant
+        d += 'C' + str(cx + rxKappa) + ' ' + str(cy - ry) + ' ' + str(cx + rx) + ' ' + str(cy - ryKappa) + ' ' + str(cx + rx) + ' ' + str(cy)
+    else:
+        d = ''
+        d += 'M' + str(cx - rx) + ',' + str(cy)
+        d += 'a' + str(rx) + ',' + str(ry) + ' 0 1,0 ' + str(2 * rx) + ',0'
+        d += 'a' + str(rx) + ',' + str(ry) + ' 0 1,0 ' + str(-2 * rx) + ',0'
 
     return d + 'z'
 
@@ -62,6 +84,9 @@ def polyline2pathd(polyline, is_polygon=False):
     else:
         points = COORD_PAIR_TMPLT.findall(polyline.get('points', ''))
 
+    if len(points) == 0:
+        return ''
+
     closed = (float(points[0][0]) == float(points[-1][0]) and
               float(points[0][1]) == float(points[-1][1]))
 
@@ -77,13 +102,13 @@ def polyline2pathd(polyline, is_polygon=False):
     return d
 
 
-def polygon2pathd(polyline):
+def polygon2pathd(polyline, is_polygon=True):
     """converts the string from a polygon points-attribute to a string 
     for a Path object d-attribute.
     Note:  For a polygon made from n points, the resulting path will be
     composed of n lines (even if some of these lines have length zero).
     """
-    return polyline2pathd(polyline, True)
+    return polyline2pathd(polyline, is_polygon)
 
 
 def rect2pathd(rect):
@@ -205,7 +230,7 @@ def dom2dict(element):
     # path strings, add to list
     if convert_polygons_to_paths:
         pgons = [dom2dict(el) for el in doc.getElementsByTagName('polygon')]
-        d_strings += [polygon2pathd(pg) for pg in pgons]
+        d_strings += [polygon2pathd(pg, True) for pg in pgons]
         attribute_dictionary_list += pgons
 
     if convert_lines_to_paths:

test/test_svg2paths.py

@@ -168,6 +168,44 @@ def test_from_string(self):
 
             self.assertEqual(len(paths), 2)
 
+    def test_svg2paths_polygon_no_points(self):
+
+        paths, _ = svg2paths(join(dirname(__file__), 'polygons_no_points.svg'))
+
+        path = paths[0]
+        path_correct = Path()
+        self.assertTrue(len(path)==0)
+        self.assertTrue(path==path_correct)
+
+        path = paths[1]
+        self.assertTrue(len(path)==0)
+        self.assertTrue(path==path_correct)
+
+    def test_svg2paths_polyline_tests(self):
+
+        paths, _ = svg2paths(join(dirname(__file__), 'polyline.svg'))
+
+        path = paths[0]
+        path_correct = Path(Line(59+185j, 98+203j),
+                            Line(98+203j, 108+245j),
+                            Line(108+245j, 82+279j),
+                            Line(82+279j, 39+280j),
+                            Line(39+280j, 11+247j),
+                            Line(11+247j, 19+205j))
+        self.assertFalse(path.isclosed())
+        self.assertTrue(len(path)==6)
+        self.assertTrue(path==path_correct)
+
+        path = paths[1]
+        path_correct = Path(Line(220+50j, 267+84j),
+                            Line(267+84j, 249+140j),
+                            Line(249+140j, 190+140j),
+                            Line(190+140j, 172+84j),
+                            Line(172+84j, 220+50j))
+        self.assertTrue(path.isclosed())
+        self.assertTrue(len(path)==5)
+        self.assertTrue(path==path_correct)
+
 
 if __name__ == '__main__':
     unittest.main()