Method transmute

lib/matplotlib/patches.py:3922–3987

(self, path, mutation_size, linewidth)

            super().__init__()

        def transmute(self, path, mutation_size, linewidth):
            # docstring inherited
            x0, y0, x1, y1, x2, y2 = self.ensure_quadratic_bezier(path)

            # divide the path into a head and a tail
            head_length = self.head_length * mutation_size
            arrow_path = [(x0, y0), (x1, y1), (x2, y2)]

            # path for head
            in_f = inside_circle(x2, y2, head_length)
            try:
                path_out, path_in = split_bezier_intersecting_with_closedpath(
                    arrow_path, in_f)
            except NonIntersectingPathException:
                # if this happens, make a straight line of the head_length
                # long.
                x0, y0 = _point_along_a_line(x2, y2, x1, y1, head_length)
                x1n, y1n = 0.5 * (x0 + x2), 0.5 * (y0 + y2)
                arrow_path = [(x0, y0), (x1n, y1n), (x2, y2)]
                path_head = arrow_path
            else:
                path_head = path_in

            # path for head
            in_f = inside_circle(x2, y2, head_length * .8)
            path_out, path_in = split_bezier_intersecting_with_closedpath(
                arrow_path, in_f)
            path_tail = path_out

            # head
            head_width = self.head_width * mutation_size
            head_l, head_r = make_wedged_bezier2(path_head,
                                                 head_width / 2.,
                                                 wm=.6)

            # tail
            tail_width = self.tail_width * mutation_size
            tail_left, tail_right = make_wedged_bezier2(path_tail,
                                                        tail_width * .5,
                                                        w1=1., wm=0.6, w2=0.3)

            # path for head
            in_f = inside_circle(x0, y0, tail_width * .3)
            path_in, path_out = split_bezier_intersecting_with_closedpath(
                arrow_path, in_f)
            tail_start = path_in[-1]

            head_right, head_left = head_r, head_l
            patch_path = [(Path.MOVETO, tail_start),
                          (Path.LINETO, tail_right[0]),
                          (Path.CURVE3, tail_right[1]),
                          (Path.CURVE3, tail_right[2]),
                          (Path.LINETO, head_right[0]),
                          (Path.CURVE3, head_right[1]),
                          (Path.CURVE3, head_right[2]),
                          (Path.CURVE3, head_left[1]),
                          (Path.CURVE3, head_left[0]),
                          (Path.LINETO, tail_left[2]),