def calculateUpVXfo(self, boneXfos, endXfo):
"""Calculates the transform for the UpV control.
Args:
boneXfos (list): Bone transforms.
endXfo (Xfo): Transform for the end of the chain.
Returns:
Xfo: Up Vector transform.
"""
# Calculate FW
toFirst = boneXfos[1].tr.subtract(boneXfos[0].tr).unit()
toTip = endXfo.tr.subtract(boneXfos[0].tr).unit()
fw = toTip.cross(toFirst).unit()
chainNormal = fw.cross(toTip).unit()
chainZAxis = toTip.cross(chainNormal).unit()
chainXfo = Xfo()
chainXfo.setFromVectors(toTip.unit(), chainNormal, chainZAxis,
boneXfos[0].tr)
rootToTip = endXfo.tr.subtract(boneXfos[0].tr).length()
upVXfo = Xfo()
upVXfo.tr = chainXfo.transformVector(
Vec3(rootToTip / 2.0, rootToTip / 2.0, 0.0))
return upVXfo
def calculateUpVXfo(self, boneXfos, endXfo):
"""Calculates the transform for the UpV control.
Args:
boneXfos (list): Bone transforms.
endXfo (Xfo): Transform for the end of the chain.
Returns:
Xfo: Up Vector transform.
"""
# Calculate FW
toFirst = boneXfos[1].tr.subtract(boneXfos[0].tr).unit()
toTip = endXfo.tr.subtract(boneXfos[0].tr).unit()
fw = toTip.cross(toFirst).unit()
chainNormal = fw.cross(toTip).unit()
chainZAxis = toTip.cross(chainNormal).unit()
chainXfo = Xfo()
chainXfo.setFromVectors(toTip.unit(), chainNormal, chainZAxis, boneXfos[0].tr)
rootToTip = endXfo.tr.subtract(boneXfos[0].tr).length()
upVXfo = Xfo()
upVXfo.tr = chainXfo.transformVector(Vec3(rootToTip / 2.0, rootToTip / 2.0, 0.0))
return upVXfo
