svgpathtoolss/test/test_groups.py

from __future__ import division, absolute_import, print_function
import unittest
from svgpathtools import *
from os.path import join, dirname
import numpy as np


def get_desired_path(name, paths):
    return next(p for p in paths if p.element.get('{some://testuri}name') == name)


def column_vector(values):
    input = []
    for value in values:
        input.append([value])
    return np.matrix(input)


class TestGroups(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 check_line(self, tf, v_s_vals, v_e_relative_vals, name, paths):
        # Check that the endpoints of the line have been correctly transformed.
        # * tf is the transform that should have been applied.
        # * v_s_vals is a 2D list of the values of the line's start point
        # * v_e_relative_vals is a 2D list of the values of the line's end point relative to the start point
        # * name is the path name (value of the test:name attribute in the SVG document)
        # * paths is the output of doc.flatten_all_paths()
        v_s_vals.append(1.0)
        v_e_relative_vals.append(0.0)
        v_s = column_vector(v_s_vals)
        v_e = v_s + column_vector(v_e_relative_vals)

        actual = get_desired_path(name, paths)

        self.check_values(tf.dot(v_s), actual.path.start)
        self.check_values(tf.dot(v_e), actual.path.end)

    def test_group_flatten(self):
        # Test the Document.flatten_all_paths() function against the groups.svg test file.
        # There are 12 paths in that file, with various levels of being nested inside of group transforms.
        # The check_line function is used to reduce the boilerplate, since all the tests are very similar.
        # This test covers each of the different types of transforms that are specified by the SVG standard.
        doc = Document(join(dirname(__file__), 'groups.svg'))

        result = doc.flatten_all_paths()
        self.assertEqual(12, len(result))

        tf_matrix_group = np.matrix([[1.5, 0.0, -40.0], [0.0, 0.5, 20.0], [0.0, 0.0, 1.0]])

        self.check_line(tf_matrix_group,
                        [183, 183], [0.0, -50],
                        'path00', result)

        tf_scale_group = np.matrix([[1.25, 0.0, 0.0], [0.0, 1.25, 0.0], [0.0, 0.0, 1.0]])

        self.check_line(tf_matrix_group.dot(tf_scale_group),
                        [122, 320], [-50.0, 0.0],
                        'path01', result)

        self.check_line(tf_matrix_group.dot(tf_scale_group),
                        [150, 200], [-50, 25],
                        'path02', result)

        self.check_line(tf_matrix_group.dot(tf_scale_group),
                        [150, 200], [-50, 25],
                        'path03', result)

        tf_nested_translate_group = np.matrix([[1, 0, 20], [0, 1, 0], [0, 0, 1]])

        self.check_line(tf_matrix_group.dot(tf_scale_group).dot(tf_nested_translate_group),
                        [150, 200], [-50, 25],
                        'path04', result)

        tf_nested_translate_xy_group = np.matrix([[1, 0, 20], [0, 1, 30], [0, 0, 1]])

        self.check_line(tf_matrix_group.dot(tf_scale_group).dot(tf_nested_translate_xy_group),
                        [150, 200], [-50, 25],
                        'path05', result)

        tf_scale_xy_group = np.matrix([[0.5, 0, 0], [0, 1.5, 0.0], [0, 0, 1]])

        self.check_line(tf_matrix_group.dot(tf_scale_xy_group),
                        [122, 320], [-50, 0],
                        'path06', result)

        a_07 = 20.0*np.pi/180.0
        tf_rotate_group = np.matrix([[np.cos(a_07), -np.sin(a_07), 0],
                                     [np.sin(a_07),  np.cos(a_07), 0],
                                     [0, 0, 1]])

        self.check_line(tf_matrix_group.dot(tf_rotate_group),
                        [183, 183], [0, 30],
                        'path07', result)

        a_08 = 45.0*np.pi/180.0
        tf_rotate_xy_group_R = np.matrix([[np.cos(a_08), -np.sin(a_08), 0],
                                          [np.sin(a_08),  np.cos(a_08), 0],
                                          [0, 0, 1]])
        tf_rotate_xy_group_T = np.matrix([[1, 0, 183], [0, 1, 183], [0, 0, 1]])
        tf_rotate_xy_group = tf_rotate_xy_group_T.dot(tf_rotate_xy_group_R).dot(np.linalg.inv(tf_rotate_xy_group_T))

        self.check_line(tf_matrix_group.dot(tf_rotate_xy_group),
                        [183, 183], [0, 30],
                        'path08', result)

        a_09 = 5.0*np.pi/180.0
        tf_skew_x_group = np.matrix([[1, np.tan(a_09), 0], [0, 1, 0], [0, 0, 1]])

        self.check_line(tf_matrix_group.dot(tf_skew_x_group),
                        [183, 183], [40, 40],
                        'path09', result)

        a_10 = 5.0*np.pi/180.0
        tf_skew_y_group = np.matrix([[1, 0, 0], [np.tan(a_10), 1, 0], [0, 0, 1]])

        self.check_line(tf_matrix_group.dot(tf_skew_y_group),
                        [183, 183], [40, 40],
                        'path10', result)

        # This last test is for handling transforms that are defined as attributes of a <path> element.
        a_11 = -40*np.pi/180.0
        tf_path11_R = np.matrix([[np.cos(a_11), -np.sin(a_11), 0],
                                 [np.sin(a_11),  np.cos(a_11), 0],
                                 [0, 0, 1]])
        tf_path11_T = np.matrix([[1, 0, 100], [0, 1, 100], [0, 0, 1]])
        tf_path11 = tf_path11_T.dot(tf_path11_R).dot(np.linalg.inv(tf_path11_T))

        self.check_line(tf_matrix_group.dot(tf_skew_y_group).dot(tf_path11),
                        [180, 20], [-70, 80],
                        'path11', result)

    def check_group_count(self, doc, expected_count):
        count = 0
        for group in doc.tree.getroot().iter('{{{0}}}g'.format(SVG_NAMESPACE['svg'])):
            count += 1

        self.assertEqual(expected_count, count)

    def test_add_group(self):
        # Test the Document.add_group() function and related Document functions.
        doc = Document(None)
        self.check_group_count(doc, 0)

        base_group = doc.add_group()
        base_group.set('id', 'base_group')
        self.assertTrue(doc.contains_group(base_group))
        self.check_group_count(doc, 1)

        child_group = doc.add_group(parent=base_group)
        child_group.set('id', 'child_group')
        self.assertTrue(doc.contains_group(child_group))
        self.check_group_count(doc, 2)

        grandchild_group = doc.add_group(parent=child_group)
        grandchild_group.set('id', 'grandchild_group')
        self.assertTrue(doc.contains_group(grandchild_group))
        self.check_group_count(doc, 3)

        sibling_group = doc.add_group(parent=base_group)
        sibling_group.set('id', 'sibling_group')
        self.assertTrue(doc.contains_group(sibling_group))
        self.check_group_count(doc, 4)

        # Test that we can retrieve each new group from the document
        self.assertEqual(base_group, doc.get_or_add_group(['base_group']))
        self.assertEqual(child_group, doc.get_or_add_group(['base_group', 'child_group']))
        self.assertEqual(grandchild_group, doc.get_or_add_group(['base_group', 'child_group', 'grandchild_group']))
        self.assertEqual(sibling_group, doc.get_or_add_group(['base_group', 'sibling_group']))

        # Create a new nested group
        new_child = doc.get_or_add_group(['base_group', 'new_parent', 'new_child'])
        self.check_group_count(doc, 6)
        self.assertEqual(new_child, doc.get_or_add_group(['base_group', 'new_parent', 'new_child']))

        new_leaf = doc.get_or_add_group(['base_group', 'new_parent', 'new_child', 'new_leaf'])
        self.assertEqual(new_leaf, doc.get_or_add_group(['base_group', 'new_parent', 'new_child', 'new_leaf']))
        self.check_group_count(doc, 7)

        path_d = 'M 206.07112,858.41289 L 206.07112,-2.02031 C -50.738,-81.14814 -20.36402,-105.87055 ' \
                 '52.52793,-101.01525 L 103.03556,0.0 L 0.0,111.11678'

        svg_path = doc.add_path(path_d, group=new_leaf)
        self.assertEqual(path_d, svg_path.get('d'))

        path = parse_path(path_d)
        svg_path = doc.add_path(path, group=new_leaf)
        self.assertEqual(path_d, svg_path.get('d'))