def __init__(self, bandgap=555, origin=(0, 0, 0), size=(1, 1, 1), shape="box"):
super(Channel, self).__init__()
self.origin = np.array(origin)
self.size = np.array(size)
self.volume = 1
if shape == "box":
self.shape = Box(origin=origin, extent=np.array(origin) + np.array(size))
for coord in size:
self.volume *= coord
elif shape == "cylinder": # takes radius, length
# The following is a little workaround to convert origin, size into cylinder (radius, length) descriptors
# Axis is based on the longest direction among the size (x,y,z)
axis = np.argmax(size)
# Length is the value of the longest axis of size
length = np.amax(size)
# Radius is the average of the other two coordinates divided by two (radius, not diameter!)
radius = np.average(np.delete(size, axis)) / 2 # Div. by 2 cause what's given it's the diameter
# Cylinder volume formula
self.volume = math.pi * radius ** 2 * length
self.shape = Cylinder(radius=radius, length=length)
# For CSG first rotation then translation (assuming scaling is not needed)
if axis == 0: # Z to X Rotation needed
self.shape.append_transform(tf.rotation_matrix(math.pi / 2.0, [0, 1, 0]))
elif axis == 1: # Z to Y Rotation needed
self.shape.append_transform(tf.rotation_matrix(-math.pi / 2.0, [1, 0, 0]))
self.shape.append_transform(tf.translation_matrix(origin))
else:
self.logger.warn("The channel shape is invalid (neither box nor cylinder. It was " + str(shape))
raise Exception("Channel has invalid shape")
self.material = SimpleMaterial(bandgap)
self.name = "Channel"
def __init__(self, bandgap=555, base=1, alpha=np.pi / 3, beta=np.pi / 3, length=1):
super(Prism, self).__init__()
h = base * (1 / np.tan(alpha) + 1 / np.tan(alpha))
box0 = Box(origin=(0, 0, 0), extent=(base, h, length))
box1 = Box(origin=(0, 0, 0), extent=(h / np.sin(alpha), h, length))
box1.append_transform(tf.rotation_matrix(alpha, (0, 0, 1)))
box2 = Box(origin=(base, 0, 0), extent=(base + h, h / np.sin(beta), h, length))
box2.append_transform(tf.rotation_matrix(np.pi / 2 - beta, (0, 0, 1)))
step1 = CSGsub(box0, box1)
step2 = CSGsub(step1, box2)
self.shape = step2
self.material = SimpleMaterial(bandgap)
def transform_direction(direction, transform):
angle, axis, point = tf.rotation_from_matrix(transform)
rotation_transform = tf.rotation_matrix(angle, axis)
return np.array(
np.dot(rotation_transform,
np.matrix(np.concatenate(
(direction,
[1.]))).transpose()).transpose()[0, 0:3]).squeeze()
def transform_direction(direction, transform):
try:
rotation_angle, rotation_axis, point = tf.rotation_from_matrix(transform)
except ValueError:
if tf.is_same_transform(tf.identity_matrix() * -1, transform):
# The ray direction needs to be reversed
return np.array(direction) * -1.
rotation_transform = tf.rotation_matrix(rotation_angle, rotation_axis)
return np.array(np.dot(rotation_transform,
np.matrix(np.concatenate((direction, [1.]))).transpose()).transpose()[0,0:3]).squeeze()
def rotation_matrix_from_vector_alignment(before, after):
"""
:param before: vector before rotation
:param after: vector after rotation
:return: rotation matrix
"""
"""
>>> # General input/output test
>>> V1 = norm(np.random.random(3))
>>> V2 = norm([1, 1, 1])
>>> R = rotation_matrix_from_vector_alignment(V1, V2)
>>> V3 = transform_direction(V1, R)
>>> cmp_points(V2, V3)
True
>>> # Catch the special case in which we cannot take the cross product
>>> V1 = [0, 0, 1]
>>> V2 = [0, 0, 1]
>>> R = rotation_matrix_from_vector_alignment(V1, V2)
>>> V3 = transform_direction(V1, R)
>>> cmp_points(V2, V3)
True
>>> # Catch the special case in which we cannot take the cross product
>>> V1 = [0, 0, 1]
>>> V2 = [0, 0, -1]
>>> R = rotation_matrix_from_vector_alignment(V1, V2)
>>> V3 = transform_direction(V1, R)
>>> cmp_points(V2, V3)
True
"""
# The angle between the vectors must not be 0 or 180 (i.e. so we can take a cross product)
# import pdb; pdb.set_trace()
the_dot = np.dot(before, after)
if cmp_floats(the_dot, 1.):
# Vectors are parallel
return tf.identity_matrix()
if cmp_floats(the_dot, -1.):
# Vectors are anti-parallel
# print "Vectors are anti-parallel this might crash."
return tf.identity_matrix() * -1.
rotation_axis = np.cross(before, after) # get the axis of rotation
rotation_angle = np.arccos(np.dot(before, after)) # get the rotation angle
return rotation_matrix(rotation_angle, rotation_axis)
def rotate(self, angle, axis):
self.shape.append_transform(tf.rotation_matrix(angle, axis))
def rotate(self, angle, axis):
self.shape.append_transform(tf.rotation_matrix(angle, axis))
def transform_direction(direction, transform):
angle, axis, point = tf.rotation_from_matrix(transform)
rotation_transform = tf.rotation_matrix(angle, axis)
return np.array(np.dot(rotation_transform,
np.matrix(np.concatenate((direction, [1.]))).transpose()).transpose()[0, 0:3]).squeeze()
