def rotations_global(anim):
"""
Global Animation Rotations
This relies on joint ordering
being incremental. That means a joint
J1 must not be a ancestor of J0 if
J0 appears before J1 in the joint
ordering.
Parameters
----------
anim : Animation
Input animation
Returns
-------
points : (F, J) Quaternions
global rotations for every frame F
and joint J
"""
joints = np.arange(anim.shape[1])
parents = np.arange(anim.shape[1])
locals = anim.rotations
globals = Quaternions.id(anim.shape)
globals[:, 0] = locals[:, 0]
for i in range(1, anim.shape[1]):
globals[:, i] = globals[:, anim.parents[i]] * locals[:, i]
return globals
def orients_global(anim):
joints = np.arange(anim.shape[1])
parents = np.arange(anim.shape[1])
locals = anim.orients
globals = Quaternions.id(anim.shape[1])
globals[:, 0] = locals[:, 0]
for i in range(1, anim.shape[1]):
globals[:, i] = globals[:, anim.parents[i]] * locals[:, i]
return globals
def jacobian(self, x, fp, fr, goal, weights, des_r, des_t):
""" Find parent rotations """
prs = fr[:, self.animation.parents]
prs[:, 0] = Quaternions.id((1))
""" Get partial rotations """
qys = Quaternions.from_angle_axis(x[:, 1:prs.shape[1] * 3:3],
np.array([[[0, 1, 0]]]))
qzs = Quaternions.from_angle_axis(x[:, 2:prs.shape[1] * 3:3],
np.array([[[0, 0, 1]]]))
""" Find axis of rotations """
es = np.empty((len(x), fr.shape[1] * 3, 3))
es[:, 0::3] = ((prs * qzs) * qys) * np.array([[[1, 0, 0]]])
es[:, 1::3] = ((prs * qzs) * np.array([[[0, 1, 0]]]))
es[:, 2::3] = ((prs * np.array([[[0, 0, 1]]])))
""" Construct Jacobian """
j = fp.repeat(3, axis=1)
j = des_r[np.newaxis, :, :, :,
np.newaxis] * (goal[:, np.newaxis, :, np.newaxis] -
j[:, :, np.newaxis, np.newaxis])
j = np.sum(j * weights[np.newaxis, np.newaxis, :, :, np.newaxis], 3)
j = self.cross(es[:, :, np.newaxis, :], j)
j = np.swapaxes(
j.reshape((len(x), fr.shape[1] * 3, goal.shape[1] * 3)), 1, 2)
if self.translate:
es = np.empty((len(x), fr.shape[1] * 3, 3))
es[:, 0::3] = prs * np.array([[[1, 0, 0]]])
es[:, 1::3] = prs * np.array([[[0, 1, 0]]])
es[:, 2::3] = prs * np.array([[[0, 0, 1]]])
jt = des_t[np.newaxis, :, :, :,
np.newaxis] * es[:, :, np.newaxis,
np.newaxis, :].repeat(goal.shape[1],
axis=2)
jt = np.sum(jt * weights[np.newaxis, np.newaxis, :, :, np.newaxis],
3)
jt = np.swapaxes(
jt.reshape((len(x), fr.shape[1] * 3, goal.shape[1] * 3)), 1, 2)
j = np.concatenate([j, jt], axis=-1)
return j
def jacobian(self, x, fp, fr, ts, dsc, tdsc):
""" Find parent rotations """
prs = fr[:, self.animation.parents]
prs[:, 0] = Quaternions.id((1))
""" Find global positions of target joints """
tps = fp[:, np.array(list(ts.keys()))]
""" Get partial rotations """
qys = Quaternions.from_angle_axis(x[:, 1:prs.shape[1] * 3:3],
np.array([[[0, 1, 0]]]))
qzs = Quaternions.from_angle_axis(x[:, 2:prs.shape[1] * 3:3],
np.array([[[0, 0, 1]]]))
""" Find axis of rotations """
es = np.empty((len(x), fr.shape[1] * 3, 3))
es[:, 0::3] = ((prs * qzs) * qys) * np.array([[[1, 0, 0]]])
es[:, 1::3] = ((prs * qzs) * np.array([[[0, 1, 0]]]))
es[:, 2::3] = ((prs * np.array([[[0, 0, 1]]])))
""" Construct Jacobian """
j = fp.repeat(3, axis=1)
j = dsc[np.newaxis, :, :,
np.newaxis] * (tps[:, np.newaxis, :] - j[:, :, np.newaxis])
j = self.cross(es[:, :, np.newaxis, :], j)
j = np.swapaxes(j.reshape((len(x), fr.shape[1] * 3, len(ts) * 3)), 1,
2)
if self.translate:
es = np.empty((len(x), fr.shape[1] * 3, 3))
es[:, 0::3] = prs * np.array([[[1, 0, 0]]])
es[:, 1::3] = prs * np.array([[[0, 1, 0]]])
es[:, 2::3] = prs * np.array([[[0, 0, 1]]])
jt = tdsc[np.newaxis, :, :,
np.newaxis] * es[:, :, np.newaxis, :].repeat(
tps.shape[1], axis=2)
jt = np.swapaxes(
jt.reshape((len(x), fr.shape[1] * 3, len(ts) * 3)), 1, 2)
j = np.concatenate([j, jt], axis=-1)
return j
def load(filename, start=None, end=None, order=None, world=False):
"""
Reads a BVH file and constructs an animation
Parameters
----------
filename: str
File to be opened
start : int
Optional Starting Frame
end : int
Optional Ending Frame
order : str
Optional Specifier for joint order.
Given as string E.G 'xyz', 'zxy'
world : bool
If set to true euler angles are applied
together in world space rather than local
space
Returns
-------
(animation, joint_names, frametime)
Tuple of loaded animation and joint names
"""
f = open(filename, "r")
i = 0
active = -1
end_site = False
names = []
orients = Quaternions.id(0)
offsets = np.array([]).reshape((0, 3))
parents = np.array([], dtype=int)
for line in f:
if "HIERARCHY" in line: continue
if "MOTION" in line: continue
rmatch = re.match(r"ROOT (\w+)", line)
if rmatch:
names.append(rmatch.group(1))
offsets = np.append(offsets, np.array([[0, 0, 0]]), axis=0)
orients.qs = np.append(orients.qs,
np.array([[1, 0, 0, 0]]),
axis=0)
parents = np.append(parents, active)
active = (len(parents) - 1)
continue
if "{" in line: continue
if "}" in line:
if end_site: end_site = False
else: active = parents[active]
continue
offmatch = re.match(
r"\s*OFFSET\s+([\-\d\.e]+)\s+([\-\d\.e]+)\s+([\-\d\.e]+)", line)
if offmatch:
if not end_site:
offsets[active] = np.array(
[list(map(float, offmatch.groups()))])
continue
chanmatch = re.match(r"\s*CHANNELS\s+(\d+)", line)
if chanmatch:
channels = int(chanmatch.group(1))
if order is None:
channelis = 0 if channels == 3 else 3
channelie = 3 if channels == 3 else 6
parts = line.split()[2 + channelis:2 + channelie]
if any([p not in channelmap for p in parts]):
continue
order = "".join([channelmap[p] for p in parts])
continue
jmatch = re.match("\s*JOINT\s+(\w+)", line)
if jmatch:
names.append(jmatch.group(1))
offsets = np.append(offsets, np.array([[0, 0, 0]]), axis=0)
orients.qs = np.append(orients.qs,
np.array([[1, 0, 0, 0]]),
axis=0)
parents = np.append(parents, active)
active = (len(parents) - 1)
continue
if "End Site" in line:
end_site = True
continue
fmatch = re.match("\s*Frames:\s+(\d+)", line)
if fmatch:
if start and end:
fnum = (end - start) - 1
else:
fnum = int(fmatch.group(1))
jnum = len(parents)
# result: [fnum, J, 3]
positions = offsets[np.newaxis].repeat(fnum, axis=0)
# result: [fnum, len(orients), 3]
rotations = np.zeros((fnum, len(orients), 3))
continue
fmatch = re.match("\s*Frame Time:\s+([\d\.]+)", line)
if fmatch:
frametime = float(fmatch.group(1))
continue
if (start and end) and (i < start or i >= end - 1):
i += 1
continue
dmatch = line.strip().split()
if dmatch:
data_block = np.array(list(map(float, dmatch)))
N = len(parents)
fi = i - start if start else i
if channels == 3:
# This should be root positions[0:1] & all rotations
positions[fi, 0:1] = data_block[0:3]
rotations[fi, :] = data_block[3:].reshape(N, 3)
elif channels == 6:
data_block = data_block.reshape(N, 6)
# fill in all positions
positions[fi, :] = data_block[:, 0:3]
rotations[fi, :] = data_block[:, 3:6]
elif channels == 9:
positions[fi, 0] = data_block[0:3]
data_block = data_block[3:].reshape(N - 1, 9)
rotations[fi, 1:] = data_block[:, 3:6]
positions[fi, 1:] += data_block[:, 0:3] * data_block[:, 6:9]
else:
raise Exception("Too many channels! %i" % channels)
i += 1
f.close()
rotations = Quaternions.from_euler(np.radians(rotations),
order=order,
world=world)
return (Animation(rotations, positions, orients, offsets,
parents), names, frametime)
def rotations_parents_global(anim):
rotations = rotations_global(anim)
rotations = rotations[:, anim.parents]
rotations[:, 0] = Quaternions.id(len(anim))
return rotations
def load_from_maya(root, start, end):
"""
Load Animation Object from Maya Joint Skeleton
Parameters
----------
root : PyNode
Root Joint of Maya Skeleton
start, end : int, int
Start and End frame index of Maya Animation
Returns
-------
animation : Animation
Loaded animation from maya
names : [str]
Joint names from maya
"""
import pymel.core as pm
original_time = pm.currentTime(q=True)
pm.currentTime(start)
""" Build Structure """
names, parents = AnimationStructure.load_from_maya(root)
descendants = AnimationStructure.descendants_list(parents)
orients = Quaternions.id(len(names))
offsets = np.array([pm.xform(j, q=True, translation=True) for j in names])
for j, name in enumerate(names):
scale = pm.xform(pm.PyNode(name), q=True, scale=True, relative=True)
if len(descendants[j]) == 0: continue
offsets[descendants[j]] *= scale
""" Load Animation """
eulers = np.zeros((end - start, len(names), 3))
positions = np.zeros((end - start, len(names), 3))
rotations = Quaternions.id((end - start, len(names)))
for i in range(end - start):
pm.currentTime(start + i + 1, u=True)
scales = {}
for j, name, parent in zip(range(len(names)), names, parents):
node = pm.PyNode(name)
if i == 0 and pm.hasAttr(node, 'jointOrient'):
ort = node.getOrientation()
orients[j] = Quaternions(
np.array([ort[3], ort[0], ort[1], ort[2]]))
if pm.hasAttr(node, 'rotate'):
eulers[i, j] = np.radians(pm.xform(node, q=True,
rotation=True))
if pm.hasAttr(node, 'translate'):
positions[i, j] = pm.xform(node, q=True, translation=True)
if pm.hasAttr(node, 'scale'):
scales[j] = pm.xform(node, q=True, scale=True, relative=True)
for j in scales:
if len(descendants[j]) == 0: continue
positions[i, descendants[j]] *= scales[j]
positions[i, 0] = pm.xform(root,
q=True,
translation=True,
worldSpace=True)
rotations = orients[np.newaxis] * Quaternions.from_euler(
eulers, order='xyz', world=True)
""" Done """
pm.currentTime(original_time)
return Animation(rotations, positions, orients, offsets, parents), names