Python pen.Pen类代码示例

def test_mode_error():
    p = Pen()
    # Don't set a mode.
    assert_raises(
        AttributeError,
        lambda: p.line_forward(1)
    )

def test_circle_degenerate():
    p = Pen()
    p.stroke_mode(2.0)
    p.circle(1)
    assert_equal(
        p.paper.svg_elements(0),
        ['<path d="M2,0 A 2,2 0 0 0 -2,0 A 2,2 0 0 0 2,0 z" fill="#000000" />']
    )

def test_circle():
    p = Pen()
    p.fill_mode()
    p.circle(1)

    assert_equal(
        p.paper.svg_elements(0),
        ['<path d="M1,0 A 1,1 0 0 0 -1,0 A 1,1 0 0 0 1,0 z" fill="#000000" />']
    )

def test_color_formats():
    for color, output in [
        (
            (1.0, 0.0, 0.0),
            '#ff0000',
        ),
        (
            Color.NewFromHtml('red'),
            '#ff0000',
        ),
        (
            'green',
            '#008000',
        ),
        (
            '#123456',
            '#123456',
        ),
    ]:
        p = Pen()
        p.stroke_mode(2.0, color)
        p.move_to((0, 0))
        p.turn_to(0)
        p.line_forward(5)

        assert_equal(
            p.paper.svg_elements(0)[0],
            '<path d="M0,-1 L0,1 L5,1 L5,-1 L0,-1 z" fill="{}" />'.format(output)
        )

 def draw(offset):
     p = Pen()
     p.stroke_mode(1.0)
     p.move_to((0, 0))
     p.turn_to(0)
     p.line_forward(0.5 + offset, end_slant=45)
     return p

def test_straight_joint_headings():
    # The math in calculating joint geometry can get numerically unstable
    # very close to straight joints at various headings.
    for heading_angle in range(0, 45):
        p = Pen()
        p.stroke_mode(1.0)
        p.move_to((0, 0))
        p.turn_to(heading_angle)
        p.line_forward(10)
        p.line_forward(10)

        path = p.paper.paths[0]
        path.render_path(2)  # Doesn't crash.

        # Check that the joint angle is 90 degrees from the heading.
        assert_equal(len(p.paper.paths), 1)
        segments = p.paper.paths[0].segments
        assert_equal(len(segments), 2)
        s0, s1 = segments

        target_angle = (heading_angle + 90) % 180

        joint_angle = math.degrees(vec.heading(vec.vfrom(s0.b_right, s0.b_left)))
        assert_almost_equal(joint_angle % 180, target_angle)

        joint_angle = math.degrees(vec.heading(vec.vfrom(s1.a_right, s1.a_left)))
        assert_almost_equal(joint_angle % 180, target_angle)

def test_arc_error():
    # Don't allow drawing an arc without a center or radius.
    p = Pen()
    assert_raises(
        TypeError,
        lambda: p.arc_left(90)
    )
    assert_raises(
        TypeError,
        lambda: p.arc_right(90)
    )

def test_line():
    p = Pen()
    p.fill_mode()
    p.move_to((0, 0))
    p.turn_to(0)
    p.line_forward(5)

    assert_path_data(
        p, 0,
        'M0,0 L5,0'
    )

def test_degenerate_arc():
    p = Pen()
    p.stroke_mode(2.0)

    p.move_to((-5, 0))
    p.turn_to(0)
    p.arc_to(
        (5, 0),
        center=(0, -200),
        start_slant=-5,
        end_slant=5,
    )
    seg = p.last_segment()
    assert seg.start_joint_illegal
    assert seg.end_joint_illegal

def test_line_segments():
    p = Pen()
    p.fill_mode()

    p.move_to((0, 0))
    p.turn_to(45)
    p.line_forward(2.0)

    assert_points_equal(p.position, (sqrt2, sqrt2))
    assert_equal(len(p.paper.paths), 1)
    segments = p.last_path().segments
    for actual, target in zip(segments, [
        ((0, 0), (sqrt2, sqrt2)),
    ]):
        assert_segments_equal(actual, target)

def test_straight_joint():
    p = Pen()
    p.stroke_mode(2.0)
    p.move_to((0, 0))
    p.turn_to(0)
    p.line_forward(3)
    p.line_forward(3)

    assert_path_data(
        p, 0,
        'M0,-1 L0,1 L3,1 L6,1 L6,-1 L3,-1 L0,-1 z'
    )

def test_arc_sweep_bug():
    p = Pen()
    p.stroke_mode(2.0)

    p.move_to((3, 0))
    p.turn_to(90)
    p.arc_left(270, 3)

    assert_path_data(
        p, 0,
        'M2,0 L4,0 A 4,4 0 1 0 0,4 L0,2 A 2,2 0 1 1 2,0 z'
    )

def test_arc_normalize():
    # Arc angles larger than 360 behave correctly.
    p = Pen()
    p.fill_mode()
    p.move_to((-5, 0))
    p.turn_to(0)
    p.arc_left(360 + 90, radius=5)

    assert_path_data(
        p, 0,
        'M-5,0 A 5,5 0 0 0 0,-5'
    )

def test_arc_pie_slice():
    # Draw a "pie slice" arc that is wide enough to reach all the way to the
    # arc center.
    p = Pen()
    p.stroke_mode(1.0)
    p.move_to((0.5, 0))
    p.turn_to(90)
    p.arc_left(90, 0.5)

    assert_path_data(
        p, 0,
        'M0,0 L1,0 A 1,1 0 0 0 0,-1 L0,0 z'
    )

def test_zero_length_side():
    # It is possible and legal to create a segment that just barely goes to
    # zero on one side.
    p = Pen()
    p.stroke_mode(2.0)
    p.move_to((0, 0))
    p.turn_to(0)
    p.line_forward(1.0, end_slant=45)

    assert_path_data(
        p, 0,
        'M0,-1 L0,1 L2,-1 L0,-1 z',
    )