path: root/Tests/pens/cu2quPen_test.py

# Copyright 2016 Google Inc. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

import unittest

from fontTools.pens.cu2quPen import Cu2QuPen, Cu2QuPointPen
from . import CUBIC_GLYPHS, QUAD_GLYPHS
from .utils import DummyGlyph, DummyPointGlyph
from .utils import DummyPen, DummyPointPen
from fontTools.misc.loggingTools import CapturingLogHandler
from textwrap import dedent
import logging


MAX_ERR = 1.0


class _TestPenMixin(object):
    """Collection of tests that are shared by both the SegmentPen and the
    PointPen test cases, plus some helper methods.
    """

    maxDiff = None

    def diff(self, expected, actual):
        import difflib
        expected = str(self.Glyph(expected)).splitlines(True)
        actual = str(self.Glyph(actual)).splitlines(True)
        diff = difflib.unified_diff(
            expected, actual, fromfile='expected', tofile='actual')
        return "".join(diff)

    def convert_glyph(self, glyph, **kwargs):
        # draw source glyph onto a new glyph using a Cu2Qu pen and return it
        converted = self.Glyph()
        pen = getattr(converted, self.pen_getter_name)()
        quadpen = self.Cu2QuPen(pen, MAX_ERR, **kwargs)
        getattr(glyph, self.draw_method_name)(quadpen)
        return converted

    def expect_glyph(self, source, expected):
        converted = self.convert_glyph(source)
        self.assertNotEqual(converted, source)
        if not converted.approx(expected):
            print(self.diff(expected, converted))
            self.fail("converted glyph is different from expected")

    def test_convert_simple_glyph(self):
        self.expect_glyph(CUBIC_GLYPHS['a'], QUAD_GLYPHS['a'])
        self.expect_glyph(CUBIC_GLYPHS['A'], QUAD_GLYPHS['A'])

    def test_convert_composite_glyph(self):
        source = CUBIC_GLYPHS['Aacute']
        converted = self.convert_glyph(source)
        # components don't change after quadratic conversion
        self.assertEqual(converted, source)

    def test_convert_mixed_glyph(self):
        # this contains a mix of contours and components
        self.expect_glyph(CUBIC_GLYPHS['Eacute'], QUAD_GLYPHS['Eacute'])

    def test_reverse_direction(self):
        for name in ('a', 'A', 'Eacute'):
            source = CUBIC_GLYPHS[name]
            normal_glyph = self.convert_glyph(source)
            reversed_glyph = self.convert_glyph(source, reverse_direction=True)

            # the number of commands is the same, just their order is iverted
            self.assertTrue(
                len(normal_glyph.outline), len(reversed_glyph.outline))
            self.assertNotEqual(normal_glyph, reversed_glyph)

    def test_stats(self):
        stats = {}
        for name in CUBIC_GLYPHS.keys():
            source = CUBIC_GLYPHS[name]
            self.convert_glyph(source, stats=stats)

        self.assertTrue(stats)
        self.assertTrue('1' in stats)
        self.assertEqual(type(stats['1']), int)

    def test_addComponent(self):
        pen = self.Pen()
        quadpen = self.Cu2QuPen(pen, MAX_ERR)
        quadpen.addComponent("a", (1, 2, 3, 4, 5.0, 6.0))

        # components are passed through without changes
        self.assertEqual(str(pen).splitlines(), [
            "pen.addComponent('a', (1, 2, 3, 4, 5.0, 6.0))",
        ])


class TestCu2QuPen(unittest.TestCase, _TestPenMixin):

    def __init__(self, *args, **kwargs):
        super(TestCu2QuPen, self).__init__(*args, **kwargs)
        self.Glyph = DummyGlyph
        self.Pen = DummyPen
        self.Cu2QuPen = Cu2QuPen
        self.pen_getter_name = 'getPen'
        self.draw_method_name = 'draw'

    def test__check_contour_is_open(self):
        msg = "moveTo is required"
        quadpen = Cu2QuPen(DummyPen(), MAX_ERR)

        with self.assertRaisesRegex(AssertionError, msg):
            quadpen.lineTo((0, 0))
        with self.assertRaisesRegex(AssertionError, msg):
            quadpen.qCurveTo((0, 0), (1, 1))
        with self.assertRaisesRegex(AssertionError, msg):
            quadpen.curveTo((0, 0), (1, 1), (2, 2))
        with self.assertRaisesRegex(AssertionError, msg):
            quadpen.closePath()
        with self.assertRaisesRegex(AssertionError, msg):
            quadpen.endPath()

        quadpen.moveTo((0, 0))  # now it works
        quadpen.lineTo((1, 1))
        quadpen.qCurveTo((2, 2), (3, 3))
        quadpen.curveTo((4, 4), (5, 5), (6, 6))
        quadpen.closePath()

    def test__check_contour_closed(self):
        msg = "closePath or endPath is required"
        quadpen = Cu2QuPen(DummyPen(), MAX_ERR)
        quadpen.moveTo((0, 0))

        with self.assertRaisesRegex(AssertionError, msg):
            quadpen.moveTo((1, 1))
        with self.assertRaisesRegex(AssertionError, msg):
            quadpen.addComponent("a", (1, 0, 0, 1, 0, 0))

        # it works if contour is closed
        quadpen.closePath()
        quadpen.moveTo((1, 1))
        quadpen.endPath()
        quadpen.addComponent("a", (1, 0, 0, 1, 0, 0))

    def test_qCurveTo_no_points(self):
        quadpen = Cu2QuPen(DummyPen(), MAX_ERR)
        quadpen.moveTo((0, 0))

        with self.assertRaisesRegex(
                AssertionError, "illegal qcurve segment point count: 0"):
            quadpen.qCurveTo()

    def test_qCurveTo_1_point(self):
        pen = DummyPen()
        quadpen = Cu2QuPen(pen, MAX_ERR)
        quadpen.moveTo((0, 0))
        quadpen.qCurveTo((1, 1))

        self.assertEqual(str(pen).splitlines(), [
            "pen.moveTo((0, 0))",
            "pen.lineTo((1, 1))",
        ])

    def test_qCurveTo_more_than_1_point(self):
        pen = DummyPen()
        quadpen = Cu2QuPen(pen, MAX_ERR)
        quadpen.moveTo((0, 0))
        quadpen.qCurveTo((1, 1), (2, 2))

        self.assertEqual(str(pen).splitlines(), [
            "pen.moveTo((0, 0))",
            "pen.qCurveTo((1, 1), (2, 2))",
        ])

    def test_curveTo_no_points(self):
        quadpen = Cu2QuPen(DummyPen(), MAX_ERR)
        quadpen.moveTo((0, 0))

        with self.assertRaisesRegex(
                AssertionError, "illegal curve segment point count: 0"):
            quadpen.curveTo()

    def test_curveTo_1_point(self):
        pen = DummyPen()
        quadpen = Cu2QuPen(pen, MAX_ERR)
        quadpen.moveTo((0, 0))
        quadpen.curveTo((1, 1))

        self.assertEqual(str(pen).splitlines(), [
            "pen.moveTo((0, 0))",
            "pen.lineTo((1, 1))",
        ])

    def test_curveTo_2_points(self):
        pen = DummyPen()
        quadpen = Cu2QuPen(pen, MAX_ERR)
        quadpen.moveTo((0, 0))
        quadpen.curveTo((1, 1), (2, 2))

        self.assertEqual(str(pen).splitlines(), [
            "pen.moveTo((0, 0))",
            "pen.qCurveTo((1, 1), (2, 2))",
        ])

    def test_curveTo_3_points(self):
        pen = DummyPen()
        quadpen = Cu2QuPen(pen, MAX_ERR)
        quadpen.moveTo((0, 0))
        quadpen.curveTo((1, 1), (2, 2), (3, 3))

        self.assertEqual(str(pen).splitlines(), [
            "pen.moveTo((0, 0))",
            "pen.qCurveTo((0.75, 0.75), (2.25, 2.25), (3, 3))",
        ])

    def test_curveTo_more_than_3_points(self):
        # a 'SuperBezier' as described in fontTools.basePen.AbstractPen
        pen = DummyPen()
        quadpen = Cu2QuPen(pen, MAX_ERR)
        quadpen.moveTo((0, 0))
        quadpen.curveTo((1, 1), (2, 2), (3, 3), (4, 4))

        self.assertEqual(str(pen).splitlines(), [
            "pen.moveTo((0, 0))",
            "pen.qCurveTo((0.75, 0.75), (1.625, 1.625), (2, 2))",
            "pen.qCurveTo((2.375, 2.375), (3.25, 3.25), (4, 4))",
        ])

    def test_addComponent(self):
        pen = DummyPen()
        quadpen = Cu2QuPen(pen, MAX_ERR)
        quadpen.addComponent("a", (1, 2, 3, 4, 5.0, 6.0))

        # components are passed through without changes
        self.assertEqual(str(pen).splitlines(), [
            "pen.addComponent('a', (1, 2, 3, 4, 5.0, 6.0))",
        ])

    def test_ignore_single_points(self):
        pen = DummyPen()
        try:
            logging.captureWarnings(True)
            with CapturingLogHandler("py.warnings", level="WARNING") as log:
                quadpen = Cu2QuPen(pen, MAX_ERR, ignore_single_points=True)
        finally:
            logging.captureWarnings(False)
        quadpen.moveTo((0, 0))
        quadpen.endPath()
        quadpen.moveTo((1, 1))
        quadpen.closePath()

        self.assertGreaterEqual(len(log.records), 1)
        self.assertIn("ignore_single_points is deprecated",
                      log.records[0].args[0])

        # single-point contours were ignored, so the pen commands are empty
        self.assertFalse(pen.commands)

        # redraw without ignoring single points
        quadpen.ignore_single_points = False
        quadpen.moveTo((0, 0))
        quadpen.endPath()
        quadpen.moveTo((1, 1))
        quadpen.closePath()

        self.assertTrue(pen.commands)
        self.assertEqual(str(pen).splitlines(), [
            "pen.moveTo((0, 0))",
            "pen.endPath()",
            "pen.moveTo((1, 1))",
            "pen.closePath()"
        ])


class TestCu2QuPointPen(unittest.TestCase, _TestPenMixin):

    def __init__(self, *args, **kwargs):
        super(TestCu2QuPointPen, self).__init__(*args, **kwargs)
        self.Glyph = DummyPointGlyph
        self.Pen = DummyPointPen
        self.Cu2QuPen = Cu2QuPointPen
        self.pen_getter_name = 'getPointPen'
        self.draw_method_name = 'drawPoints'

    def test_super_bezier_curve(self):
        pen = DummyPointPen()
        quadpen = Cu2QuPointPen(pen, MAX_ERR)
        quadpen.beginPath()
        quadpen.addPoint((0, 0), segmentType="move")
        quadpen.addPoint((1, 1))
        quadpen.addPoint((2, 2))
        quadpen.addPoint((3, 3))
        quadpen.addPoint(
            (4, 4), segmentType="curve", smooth=False, name="up", selected=1)
        quadpen.endPath()

        self.assertEqual(str(pen).splitlines(), """\
pen.beginPath()
pen.addPoint((0, 0), name=None, segmentType='move', smooth=False)
pen.addPoint((0.75, 0.75), name=None, segmentType=None, smooth=False)
pen.addPoint((1.625, 1.625), name=None, segmentType=None, smooth=False)
pen.addPoint((2, 2), name=None, segmentType='qcurve', smooth=True)
pen.addPoint((2.375, 2.375), name=None, segmentType=None, smooth=False)
pen.addPoint((3.25, 3.25), name=None, segmentType=None, smooth=False)
pen.addPoint((4, 4), name='up', segmentType='qcurve', selected=1, smooth=False)
pen.endPath()""".splitlines())

    def test__flushContour_restore_starting_point(self):
        pen = DummyPointPen()
        quadpen = Cu2QuPointPen(pen, MAX_ERR)

        # collect the output of _flushContour before it's sent to _drawPoints
        new_segments = []
        def _drawPoints(segments):
            new_segments.extend(segments)
            Cu2QuPointPen._drawPoints(quadpen, segments)
        quadpen._drawPoints = _drawPoints

        # a closed path (ie. no "move" segmentType)
        quadpen._flushContour([
            ("curve", [
                ((2, 2), False, None, {}),
                ((1, 1), False, None, {}),
                ((0, 0), False, None, {}),
            ]),
            ("curve", [
                ((1, 1), False, None, {}),
                ((2, 2), False, None, {}),
                ((3, 3), False, None, {}),
            ]),
        ])

        # the original starting point is restored: the last segment has become
        # the first
        self.assertEqual(new_segments[0][1][-1][0], (3, 3))
        self.assertEqual(new_segments[-1][1][-1][0], (0, 0))

        new_segments = []
        # an open path (ie. starting with "move")
        quadpen._flushContour([
            ("move", [
                ((0, 0), False, None, {}),
            ]),
            ("curve", [
                ((1, 1), False, None, {}),
                ((2, 2), False, None, {}),
                ((3, 3), False, None, {}),
            ]),
        ])

        # the segment order stays the same before and after _flushContour
        self.assertEqual(new_segments[0][1][-1][0], (0, 0))
        self.assertEqual(new_segments[-1][1][-1][0], (3, 3))

    def test_quad_no_oncurve(self):
        """When passed a contour which has no on-curve points, the
        Cu2QuPointPen will treat it as a special quadratic contour whose
        first point has 'None' coordinates.
        """
        self.maxDiff = None
        pen = DummyPointPen()
        quadpen = Cu2QuPointPen(pen, MAX_ERR)
        quadpen.beginPath()
        quadpen.addPoint((1, 1))
        quadpen.addPoint((2, 2))
        quadpen.addPoint((3, 3))
        quadpen.endPath()

        self.assertEqual(
            str(pen),
            dedent(
                """\
                pen.beginPath()
                pen.addPoint((1, 1), name=None, segmentType=None, smooth=False)
                pen.addPoint((2, 2), name=None, segmentType=None, smooth=False)
                pen.addPoint((3, 3), name=None, segmentType=None, smooth=False)
                pen.endPath()"""
            )
        )


if __name__ == "__main__":
    unittest.main()