void updateArmPosition(GameObject myo, ArmTransform armSegment, Quaternion _antiYaw, float _referenceRoll)
{
ThalmicMyo thalmicMyo = myo.GetComponent<ThalmicMyo> ();
bool updateReference = false;
if (myo.Equals(myoLower)) {
// Update references when the pose becomes fingers spread or the q key is pressed.
if (thalmicMyo.pose != _lastPose) {
_lastPose = thalmicMyo.pose;
if (thalmicMyo.pose == Pose.Fist) {
updateReference = true;
ExtendUnlockAndNotifyUserAction (thalmicMyo);
}
}
if (Input.GetKeyDown ("r")) {
updateReference = true;
}
}
// Update references. This anchors the joint on-screen such that it faces forward away
// from the viewer when the Myo armband is oriented the way it is when these references are taken.
if (updateReference) {
_antiYawUpper = Quaternion.FromToRotation (
new Vector3 (myoUpper.transform.forward.x, myoUpper.transform.forward.y, myoUpper.transform.forward.z),
new Vector3 (1, 0, 0)
);
// _referenceRoll represents how many degrees the Myo armband is rotated clockwise
// about its forward axis (when looking down the wearer's arm towards their hand) from the reference zero
// roll direction. This direction is calculated and explained below. When this reference is
// taken, the joint will be rotated about its forward axis such that it faces upwards when
// the roll value matches the reference.
Vector3 referenceZeroRoll = computeZeroRollVector (myoUpper.transform.forward, myoUpper);
_referenceRollUpper = rollFromZero (referenceZeroRoll, myoUpper.transform.forward, myoUpper.transform.up);
// _antiYaw represents a rotation of the Myo armband about the Y axis (up) which aligns the forward
// vector of the rotation with Z = 1 when the wearer's arm is pointing in the reference direction.
_antiYawLower = Quaternion.FromToRotation (
new Vector3 (myoLower.transform.forward.x, 0, myoLower.transform.forward.z),
new Vector3 (1,0,0)
);
_antiYaw = _antiYawLower;
// _referenceRoll represents how many degrees the Myo armband is rotated clockwise
// about its forward axis (when looking down the wearer's arm towards their hand) from the reference zero
// roll direction. This direction is calculated and explained below. When this reference is
// taken, the joint will be rotated about its forward axis such that it faces upwards when
// the roll value matches the reference.
referenceZeroRoll = computeZeroRollVector (myoLower.transform.forward, myoLower);
_referenceRollLower = rollFromZero (referenceZeroRoll, myoLower.transform.forward, myoLower.transform.up);
_referenceRoll = _referenceRollLower;
}
// Current zero roll vector and roll value.
Vector3 zeroRoll = computeZeroRollVector (myo.transform.forward, myo);
float roll = rollFromZero (zeroRoll, myo.transform.forward, myo.transform.up);
// The relative roll is simply how much the current roll has changed relative to the reference roll.
// adjustAngle simply keeps the resultant value within -180 to 180 degrees.
float relativeRoll = normalizeAngle (roll - _referenceRoll);
// antiRoll represents a rotation about the myo Armband's forward axis adjusting for reference roll.
Quaternion antiRoll = Quaternion.AngleAxis (relativeRoll, myo.transform.forward);
// Here the anti-roll and yaw rotations are applied to the myo Armband's forward direction to yield
// the orientation of the joint.
armSegment.transform.rotation = _antiYaw * antiRoll * Quaternion.LookRotation (myo.transform.forward);
// The above calculations were done assuming the Myo armbands's +x direction, in its own coordinate system,
// was facing toward the wearer's elbow. If the Myo armband is worn with its +x direction facing the other way,
// the rotation needs to be updated to compensate.
if (thalmicMyo.xDirection == Thalmic.Myo.XDirection.TowardWrist) {
// Mirror the rotation around the XZ plane in Unity's coordinate system (XY plane in Myo's coordinate
// system). This makes the rotation reflect the arm's orientation, rather than that of the Myo armband.
armSegment.transform.rotation = new Quaternion(armSegment.transform.localRotation.x,
-armSegment.transform.localRotation.y,
armSegment.transform.localRotation.z,
-armSegment.transform.localRotation.w);
}
}
void updateArmPosition(GameObject myo, ArmTransform armSegment, Quaternion _antiYaw, float _referenceRoll)
{
ThalmicMyo thalmicMyo = myo.GetComponent <ThalmicMyo> ();
bool updateReference = false;
if (myo.Equals(myoLower))
{
// Update references when the pose becomes fingers spread or the q key is pressed.
if (thalmicMyo.pose != _lastPose)
{
_lastPose = thalmicMyo.pose;
if (thalmicMyo.pose == Pose.Fist)
{
updateReference = true;
ExtendUnlockAndNotifyUserAction(thalmicMyo);
}
}
if (Input.GetKeyDown("r"))
{
updateReference = true;
}
}
// Update references. This anchors the joint on-screen such that it faces forward away
// from the viewer when the Myo armband is oriented the way it is when these references are taken.
if (updateReference)
{
_antiYawUpper = Quaternion.FromToRotation(
new Vector3(myoUpper.transform.forward.x, myoUpper.transform.forward.y, myoUpper.transform.forward.z),
new Vector3(1, 0, 0)
);
// _referenceRoll represents how many degrees the Myo armband is rotated clockwise
// about its forward axis (when looking down the wearer's arm towards their hand) from the reference zero
// roll direction. This direction is calculated and explained below. When this reference is
// taken, the joint will be rotated about its forward axis such that it faces upwards when
// the roll value matches the reference.
Vector3 referenceZeroRoll = computeZeroRollVector(myoUpper.transform.forward, myoUpper);
_referenceRollUpper = rollFromZero(referenceZeroRoll, myoUpper.transform.forward, myoUpper.transform.up);
// _antiYaw represents a rotation of the Myo armband about the Y axis (up) which aligns the forward
// vector of the rotation with Z = 1 when the wearer's arm is pointing in the reference direction.
_antiYawLower = Quaternion.FromToRotation(
new Vector3(myoLower.transform.forward.x, 0, myoLower.transform.forward.z),
new Vector3(1, 0, 0)
);
_antiYaw = _antiYawLower;
// _referenceRoll represents how many degrees the Myo armband is rotated clockwise
// about its forward axis (when looking down the wearer's arm towards their hand) from the reference zero
// roll direction. This direction is calculated and explained below. When this reference is
// taken, the joint will be rotated about its forward axis such that it faces upwards when
// the roll value matches the reference.
referenceZeroRoll = computeZeroRollVector(myoLower.transform.forward, myoLower);
_referenceRollLower = rollFromZero(referenceZeroRoll, myoLower.transform.forward, myoLower.transform.up);
_referenceRoll = _referenceRollLower;
}
// Current zero roll vector and roll value.
Vector3 zeroRoll = computeZeroRollVector(myo.transform.forward, myo);
float roll = rollFromZero(zeroRoll, myo.transform.forward, myo.transform.up);
// The relative roll is simply how much the current roll has changed relative to the reference roll.
// adjustAngle simply keeps the resultant value within -180 to 180 degrees.
float relativeRoll = normalizeAngle(roll - _referenceRoll);
// antiRoll represents a rotation about the myo Armband's forward axis adjusting for reference roll.
Quaternion antiRoll = Quaternion.AngleAxis(relativeRoll, myo.transform.forward);
// Here the anti-roll and yaw rotations are applied to the myo Armband's forward direction to yield
// the orientation of the joint.
armSegment.transform.rotation = _antiYaw * antiRoll * Quaternion.LookRotation(myo.transform.forward);
// The above calculations were done assuming the Myo armbands's +x direction, in its own coordinate system,
// was facing toward the wearer's elbow. If the Myo armband is worn with its +x direction facing the other way,
// the rotation needs to be updated to compensate.
if (thalmicMyo.xDirection == Thalmic.Myo.XDirection.TowardWrist)
{
// Mirror the rotation around the XZ plane in Unity's coordinate system (XY plane in Myo's coordinate
// system). This makes the rotation reflect the arm's orientation, rather than that of the Myo armband.
armSegment.transform.rotation = new Quaternion(armSegment.transform.localRotation.x,
-armSegment.transform.localRotation.y,
armSegment.transform.localRotation.z,
-armSegment.transform.localRotation.w);
}
}
