build local list of IK targets every frame

This commit is contained in:
Andrew Meadows 2015-09-16 12:10:22 -07:00
parent 089c719612
commit 9a86fc2e62
3 changed files with 85 additions and 55 deletions

View file

@ -55,7 +55,20 @@ void AnimInverseKinematics::computeAbsolutePoses(AnimPoseVec& absolutePoses) con
void AnimInverseKinematics::setTargetVars(const QString& jointName, const QString& positionVar, const QString& rotationVar) {
// if there are dups, last one wins.
_targetVarVec.push_back(IKTargetVar(jointName, positionVar.toStdString(), rotationVar.toStdString()));
bool found = false;
for (auto& targetVar: _targetVarVec) {
if (targetVar.jointName == jointName) {
// update existing targetVar
targetVar.positionVar = positionVar.toStdString();
targetVar.rotationVar = rotationVar.toStdString();
found = true;
break;
}
}
if (!found) {
// create a new entry
_targetVarVec.push_back(IKTargetVar(jointName, positionVar.toStdString(), rotationVar.toStdString()));
}
}
static int findRootJointInSkeleton(AnimSkeleton::ConstPointer skeleton, int index) {
@ -69,6 +82,12 @@ static int findRootJointInSkeleton(AnimSkeleton::ConstPointer skeleton, int inde
return rootIndex;
}
struct IKTarget {
AnimPose pose;
int index;
int rootIndex;
};
//virtual
const AnimPoseVec& AnimInverseKinematics::evaluate(const AnimVariantMap& animVars, float dt, AnimNode::Triggers& triggersOut) {
@ -77,40 +96,53 @@ const AnimPoseVec& AnimInverseKinematics::evaluate(const AnimVariantMap& animVar
return _relativePoses;
}
// evaluate target vars
// build a list of targets from _targetVarVec
std::vector<IKTarget> targets;
bool removeUnfoundJoints = false;
for (auto& targetVar : _targetVarVec) {
// lazy look up of jointIndices and insertion into _absoluteTargets map
if (!targetVar.hasPerformedJointLookup) {
targetVar.jointIndex = _skeleton->nameToJointIndex(targetVar.jointName);
if (targetVar.jointIndex >= 0) {
// insert into _absoluteTargets map
IKTarget target;
target.pose = AnimPose::identity;
target.rootIndex = findRootJointInSkeleton(_skeleton, targetVar.jointIndex);
_absoluteTargets[targetVar.jointIndex] = target;
if (targetVar.jointIndex > _maxTargetIndex) {
_maxTargetIndex = targetVar.jointIndex;
}
if (targetVar.jointIndex == -1) {
// this targetVar hasn't been validated yet...
int jointIndex = _skeleton->nameToJointIndex(targetVar.jointName);
if (jointIndex >= 0) {
// this targetVar has a valid joint --> cache the indices
targetVar.jointIndex = jointIndex;
targetVar.rootIndex = findRootJointInSkeleton(_skeleton, jointIndex);
} else {
qCWarning(animation) << "AnimInverseKinematics could not find jointName" << targetVar.jointName << "in skeleton";
removeUnfoundJoints = true;
}
targetVar.hasPerformedJointLookup = true;
}
if (targetVar.jointIndex >= 0) {
// update pose in _absoluteTargets map
auto iter = _absoluteTargets.find(targetVar.jointIndex);
if (iter != _absoluteTargets.end()) {
} else {
// TODO: get this done without a double-lookup of each var in animVars
if (animVars.hasKey(targetVar.positionVar) || animVars.hasKey(targetVar.rotationVar)) {
IKTarget target;
AnimPose defaultPose = _skeleton->getAbsolutePose(targetVar.jointIndex, _relativePoses);
iter->second.pose.trans = animVars.lookup(targetVar.positionVar, defaultPose.trans);
iter->second.pose.rot = animVars.lookup(targetVar.rotationVar, defaultPose.rot);
target.pose.trans = animVars.lookup(targetVar.positionVar, defaultPose.trans);
target.pose.rot = animVars.lookup(targetVar.rotationVar, defaultPose.rot);
target.rootIndex = targetVar.rootIndex;
target.index = targetVar.jointIndex;
targets.push_back(target);
}
}
}
if (_absoluteTargets.empty()) {
if (removeUnfoundJoints) {
int numVars = _targetVarVec.size();
int i = 0;
while (i < numVars) {
if (_targetVarVec[i].jointIndex == -1) {
if (numVars > 1) {
// swap i for last element
_targetVarVec[i] = _targetVarVec[numVars - 1];
}
_targetVarVec.pop_back();
--numVars;
} else {
++i;
}
}
}
if (targets.empty()) {
// no IK targets but still need to enforce constraints
std::map<int, RotationConstraint*>::iterator constraintItr = _constraints.begin();
while (constraintItr != _constraints.end()) {
@ -133,11 +165,11 @@ const AnimPoseVec& AnimInverseKinematics::evaluate(const AnimVariantMap& animVar
quint64 expiry = usecTimestampNow() + MAX_IK_TIME;
do {
largestError = 0.0f;
for (auto& targetPair: _absoluteTargets) {
for (auto& target: targets) {
int lowestMovedIndex = _relativePoses.size() - 1;
int tipIndex = targetPair.first;
AnimPose targetPose = targetPair.second.pose;
int rootIndex = targetPair.second.rootIndex;
int tipIndex = target.index;
AnimPose targetPose = target.pose;
int rootIndex = target.rootIndex;
if (rootIndex != -1) {
// transform targetPose into skeleton's absolute frame
AnimPose& rootPose = _relativePoses[rootIndex];
@ -148,11 +180,11 @@ const AnimPoseVec& AnimInverseKinematics::evaluate(const AnimVariantMap& animVar
glm::vec3 tip = absolutePoses[tipIndex].trans;
float error = glm::length(targetPose.trans - tip);
// descend toward root, rotating each joint to get tip closer to target
int index = _skeleton->getParentIndex(tipIndex);
while (index != -1 && error > ACCEPTABLE_RELATIVE_ERROR) {
// descend toward root, pivoting each joint to get tip closer to target
int pivotIndex = _skeleton->getParentIndex(tipIndex);
while (pivotIndex != -1 && error > ACCEPTABLE_RELATIVE_ERROR) {
// compute the two lines that should be aligned
glm::vec3 jointPosition = absolutePoses[index].trans;
glm::vec3 jointPosition = absolutePoses[pivotIndex].trans;
glm::vec3 leverArm = tip - jointPosition;
glm::vec3 targetLine = targetPose.trans - jointPosition;
@ -171,29 +203,34 @@ const AnimPoseVec& AnimInverseKinematics::evaluate(const AnimVariantMap& animVar
angle = 0.5f * angle;
glm::quat deltaRotation = glm::angleAxis(angle, axis);
int parentIndex = _skeleton->getParentIndex(index);
int parentIndex = _skeleton->getParentIndex(pivotIndex);
if (parentIndex == -1) {
// TODO? apply constraints to root?
// TODO? harvest the root's transform as movement of entire skeleton?
} else {
// compute joint's new parent-relative rotation
// Q' = dQ * Q and Q = Qp * q --> q' = Qp^ * dQ * Q
glm::quat newRot = glm::normalize(glm::inverse(absolutePoses[parentIndex].rot) * deltaRotation * absolutePoses[index].rot);
RotationConstraint* constraint = getConstraint(index);
glm::quat newRot = glm::normalize(glm::inverse(
absolutePoses[parentIndex].rot) *
deltaRotation *
absolutePoses[pivotIndex].rot);
RotationConstraint* constraint = getConstraint(pivotIndex);
if (constraint) {
bool constrained = constraint->apply(newRot);
if (constrained) {
// the constraint will modify the movement of the tip so we have to compute the modified
// model-frame deltaRotation
// Q' = Qp^ * dQ * Q --> dQ = Qp * Q' * Q^
deltaRotation = absolutePoses[parentIndex].rot * newRot * glm::inverse(absolutePoses[index].rot);
deltaRotation = absolutePoses[parentIndex].rot *
newRot *
glm::inverse(absolutePoses[pivotIndex].rot);
}
}
_relativePoses[index].rot = newRot;
_relativePoses[pivotIndex].rot = newRot;
}
// this joint has been changed so we check to see if it has the lowest index
if (index < lowestMovedIndex) {
lowestMovedIndex = index;
if (pivotIndex < lowestMovedIndex) {
lowestMovedIndex = pivotIndex;
}
// keep track of tip's new position as we descend towards root
@ -201,7 +238,7 @@ const AnimPoseVec& AnimInverseKinematics::evaluate(const AnimVariantMap& animVar
error = glm::length(targetPose.trans - tip);
}
}
index = _skeleton->getParentIndex(index);
pivotIndex = _skeleton->getParentIndex(pivotIndex);
}
if (largestError < error) {
largestError = error;
@ -581,13 +618,10 @@ void AnimInverseKinematics::setSkeletonInternal(AnimSkeleton::ConstPointer skele
AnimNode::setSkeletonInternal(skeleton);
// invalidate all targetVars
for (auto& targetVar : _targetVarVec) {
targetVar.hasPerformedJointLookup = false;
for (auto& targetVar: _targetVarVec) {
targetVar.jointIndex = -1;
}
// invalidate all targets
_absoluteTargets.clear();
_maxTargetIndex = 0;
if (skeleton) {

View file

@ -50,23 +50,17 @@ protected:
rotationVar(rotationVarIn),
jointName(jointNameIn),
jointIndex(-1),
hasPerformedJointLookup(false) {}
rootIndex(-1) {}
std::string positionVar;
std::string rotationVar;
QString jointName;
int jointIndex; // cached joint index
bool hasPerformedJointLookup = false;
};
struct IKTarget {
AnimPose pose;
int rootIndex;
int rootIndex; // cached root index
};
std::map<int, RotationConstraint*> _constraints;
std::vector<IKTargetVar> _targetVarVec;
std::map<int, IKTarget> _absoluteTargets; // IK targets of end-points
AnimPoseVec _defaultRelativePoses; // poses of the relaxed state
AnimPoseVec _relativePoses; // current relative poses

View file

@ -154,6 +154,8 @@ public:
void setTrigger(const std::string& key) { _triggers.insert(key); }
void clearTriggers() { _triggers.clear(); }
bool hasKey(const std::string& key) const { return _map.find(key) != _map.end(); }
protected:
std::map<std::string, AnimVariant> _map;
std::set<std::string> _triggers;