def goal(ts, *xs):
n3 = len(xs)
n = n3 // 3
control_points = np.array(xs).reshape((n, 3))
curve = SvBezierCurve(control_points)
pts = curve.evaluate_array(ts)
return np.ravel(pts)
def process(self):
if not any(socket.is_linked for socket in self.outputs):
return
vertices_s = self.inputs['Vertices'].sv_get()
degree_s = self.inputs['Degree'].sv_get()
vertices_s = ensure_nesting_level(vertices_s, 3)
degree_s = ensure_nesting_level(degree_s, 2)
curve_out = []
points_out = []
for vertices, degree in zip_long_repeat(vertices_s, degree_s):
if isinstance(degree, (tuple, list)):
degree = degree[0]
n = len(vertices)
npoints = degree + 1
vertices = np.array(vertices)
#xdata = np.linspace(0, 1, num=n)
xdata = Spline.create_knots(vertices, metric=self.metric)
ydata = np.ravel(vertices)
p0 = init_guess(vertices, npoints)
popt, pcov = curve_fit(goal, xdata, ydata, p0)
control_points = popt.reshape((npoints, 3))
curve = SvBezierCurve(control_points)
curve_out.append(curve)
points_out.append(control_points.tolist())
self.outputs['Curve'].sv_set(curve_out)
self.outputs['ControlPoints'].sv_set(points_out)
def test_third_derivs_equal(self):
ts = np.linspace(0.0, 1.0, num=10)
points = cubic_control_points()
cubic = SvCubicBezierCurve(*points)
generic = SvBezierCurve(points)
cubic_points = cubic.third_derivative_array(ts)
generic_points = generic.third_derivative_array(ts)
self.assert_numpy_arrays_equal(cubic_points, generic_points, precision=6)
def test_cubic_equals_generic(self):
ts = np.linspace(0.0, 1.0, num=10)
points = cubic_control_points()
cubic = SvCubicBezierCurve(*points)
generic = SvBezierCurve(points)
cubic_points = cubic.evaluate_array(ts)
generic_points = generic.evaluate_array(ts)
self.assert_numpy_arrays_equal(cubic_points, generic_points, precision=6)
def interpret(self, interpreter, variables):
vec = lambda v: Vector((v[0], v[1], 0))
interpreter.assert_not_closed()
interpreter.start_new_segment()
v0 = interpreter.position
if interpreter.has_last_vertex:
v0_index = interpreter.get_last_vertex()
else:
v0_index = interpreter.new_vertex(*v0)
knot1 = None
for i, segment in enumerate(self.segments):
# For first segment, knot1 is initial pen position;
# for the following, knot1 is knot2 of previous segment.
if knot1 is None:
knot1 = interpreter.position
else:
knot1 = knot2
handle = interpreter.calc_vertex(self.is_abs, segment.control[0],
segment.control[1], variables)
knot2 = interpreter.calc_vertex(self.is_abs, segment.knot2[0],
segment.knot2[1], variables)
interpreter.position = knot2
if self.num_segments is not None:
r = interpreter.eval_(self.num_segments, variables)
else:
r = interpreter.dflt_num_verts
curve = SvBezierCurve([vec(knot1), vec(handle), vec(knot2)])
interpreter.curves.append(curve)
points = interpolate_quadratic_bezier(vec(knot1), vec(handle),
vec(knot2), r)
interpreter.new_knot("Q#.{}.h".format(i), *handle)
interpreter.new_knot("Q#.{}.k".format(i), *knot2)
interpreter.prev_quad_bezier_knot = handle
for point in points[1:]:
v1_index = interpreter.new_vertex(point.x, point.y)
interpreter.new_edge(v0_index, v1_index)
v0_index = v1_index
if self.close:
interpreter.close_segment(v1_index)
interpreter.has_last_vertex = True
def process(self):
if not any(socket.is_linked for socket in self.outputs):
return
start_s = self.inputs['Start'].sv_get()
end_s = self.inputs['End'].sv_get()
knot1_s = self.inputs[CONTROL1_SOCKET].sv_get()
knot2_s = self.inputs[CONTROL2_SOCKET].sv_get()
controls_s = self.inputs['ControlPoints'].sv_get(default=[[[[]]]])
start_s = ensure_nesting_level(start_s, 3)
end_s = ensure_nesting_level(end_s, 3)
knot1_s = ensure_nesting_level(knot1_s, 3)
knot2_s = ensure_nesting_level(knot2_s, 3)
controls_s = ensure_nesting_level(controls_s, 4)
curves_out = []
controls_out = []
for starts, ends, knot1s, knot2s, controls_i in zip_long_repeat(
start_s, end_s, knot1_s, knot2_s, controls_s):
new_curves = []
new_controls = []
for start, end, knot1, knot2, controls in zip_long_repeat(
starts, ends, knot1s, knot2s, controls_i):
start, end = np.array(start), np.array(end)
knot1, knot2 = np.array(knot1), np.array(knot2)
if self.mode == CUBIC:
curve = SvCubicBezierCurve(start, knot1, knot2, end)
curve_controls = [
start.tolist(),
knot1.tolist(),
knot2.tolist(),
end.tolist()
]
elif self.mode == CUBIC_TANGENT:
curve = SvBezierCurve.from_points_and_tangents(
start, knot1, knot2, end)
curve_controls = [
curve.p0.tolist(),
curve.p1.tolist(),
curve.p2.tolist(),
curve.p3.tolist()
]
elif self.mode == CUBIC_4PT:
curve = SvCubicBezierCurve.from_four_points(
start, knot1, knot2, end)
curve_controls = [
curve.p0.tolist(),
curve.p1.tolist(),
curve.p2.tolist(),
curve.p3.tolist()
]
elif self.mode == QUADRATIC:
curve = SvBezierCurve([start, knot1, end])
curve_controls = [p.tolist() for p in curve.points]
else: # GENERIC
if not controls:
raise SvNoDataError(
socket=self.inputs['ControlPoints'], node=self)
if len(controls) < 2:
raise Exception(
"At least two control points are required to build a Bezier spline!"
)
if self.is_cyclic:
controls = controls + [controls[0]]
curve = SvBezierCurve(controls)
curve_controls = controls
new_curves.append(curve)
new_controls.extend(curve_controls)
curves_out.append(new_curves)
controls_out.append(new_controls)
self.outputs['Curve'].sv_set(curves_out)
self.outputs['ControlPoints'].sv_set(controls_out)
def interpret(self, interpreter, variables):
vec = lambda v: Vector((v[0], v[1], 0))
interpreter.assert_not_closed()
interpreter.start_new_segment()
v0 = interpreter.position
if interpreter.has_last_vertex:
v0_index = interpreter.get_last_vertex()
else:
v0_index = interpreter.new_vertex(*v0)
knot1 = None
for i, segment in enumerate(self.segments):
# For first segment, knot1 is initial pen position;
# for the following, knot1 is knot2 of previous segment.
if knot1 is None:
knot1 = interpreter.position
else:
knot1 = knot2
if interpreter.prev_quad_bezier_knot is None:
# If there is no previous command or if the previous command was
# not a Q, q, T or t, assume the control point is coincident with
# the current point.
handle = knot1
else:
# The first control point is assumed to be the reflection of the
# second control point on the previous command relative to the
# current point.
prev_knot_x, prev_knot_y = interpreter.prev_quad_bezier_knot
x0, y0 = knot1
dx, dy = x0 - prev_knot_x, y0 - prev_knot_y
handle = x0 + dx, y0 + dy
knot2 = interpreter.calc_vertex(self.is_abs, segment.knot2[0], segment.knot2[1], variables)
interpreter.position = knot2
if self.num_segments is not None:
r = interpreter.eval_(self.num_segments, variables)
else:
r = interpreter.dflt_num_verts
curve = SvBezierCurve([vec(knot1), vec(handle), vec(knot2)])
interpreter.new_curve(curve, self)
points = interpolate_quadratic_bezier(vec(knot1), vec(handle), vec(knot2), r)
interpreter.new_knot("T#.{}.h".format(i), *handle)
interpreter.new_knot("T#.{}.k".format(i), *knot2)
interpreter.prev_quad_bezier_knot = handle
for point in points[1:]:
v1_index = interpreter.new_vertex(point.x, point.y)
interpreter.new_edge(v0_index, v1_index)
v0_index = v1_index
if self.close:
interpreter.close_segment(v1_index)
interpreter.has_last_vertex = True