/// compute interpolation parameters from keyframes and an iterator
/// to the next keyframe (the first with time > t)
static void
interParams(const KeyFrameSet &keyFrames,
double t,
const KeyFrameSet::const_iterator &itup,
double *tcur,
double *vcur,
double *vcurDerivRight,
Natron::KeyframeType *interp,
double *tnext,
double *vnext,
double *vnextDerivLeft,
Natron::KeyframeType *interpNext)
{
assert(itup == keyFrames.end() || t < itup->getTime());
if (itup == keyFrames.begin()) {
//if all keys have a greater time
// get the first keyframe
*tnext = itup->getTime();
*vnext = itup->getValue();
*vnextDerivLeft = itup->getLeftDerivative();
*interpNext = itup->getInterpolation();
*tcur = *tnext - 1.;
*vcur = *vnext;
*vcurDerivRight = 0.;
*interp = Natron::KEYFRAME_NONE;
} else if (itup == keyFrames.end()) {
//if we found no key that has a greater time
// get the last keyframe
KeyFrameSet::const_reverse_iterator itlast = keyFrames.rbegin();
*tcur = itlast->getTime();
*vcur = itlast->getValue();
*vcurDerivRight = itlast->getRightDerivative();
*interp = itlast->getInterpolation();
*tnext = *tcur + 1.;
*vnext = *vcur;
*vnextDerivLeft = 0.;
*interpNext = Natron::KEYFRAME_NONE;
} else {
// between two keyframes
// get the last keyframe with time <= t
KeyFrameSet::const_iterator itcur = itup;
--itcur;
assert(itcur->getTime() <= t);
*tcur = itcur->getTime();
*vcur = itcur->getValue();
*vcurDerivRight = itcur->getRightDerivative();
*interp = itcur->getInterpolation();
*tnext = itup->getTime();
*vnext = itup->getValue();
*vnextDerivLeft = itup->getLeftDerivative();
*interpNext = itup->getInterpolation();
}
}
KeyFrameSet::iterator Curve::refreshDerivatives(Curve::CurveChangedReason reason, KeyFrameSet::iterator key)
{
// PRIVATE - should not lock
double tcur = key->getTime();
double vcur = key->getValue();
double tprev, vprev, tnext, vnext, vprevDerivRight, vnextDerivLeft;
Natron::KeyframeType prevType, nextType;
if (key == _imp->keyFrames.begin()) {
tprev = tcur;
vprev = vcur;
vprevDerivRight = 0.;
prevType = Natron::KEYFRAME_NONE;
} else {
KeyFrameSet::const_iterator prev = key;
--prev;
tprev = prev->getTime();
vprev = prev->getValue();
vprevDerivRight = prev->getRightDerivative();
prevType = prev->getInterpolation();
//if prev is the first keyframe, and not edited by the user then interpolate linearly
if (prev == _imp->keyFrames.begin() && prevType != Natron::KEYFRAME_FREE &&
prevType != Natron::KEYFRAME_BROKEN) {
prevType = Natron::KEYFRAME_LINEAR;
}
}
KeyFrameSet::const_iterator next = key;
++next;
if (next == _imp->keyFrames.end()) {
tnext = tcur;
vnext = vcur;
vnextDerivLeft = 0.;
nextType = Natron::KEYFRAME_NONE;
} else {
tnext = next->getTime();
vnext = next->getValue();
vnextDerivLeft = next->getLeftDerivative();
nextType = next->getInterpolation();
KeyFrameSet::const_iterator nextnext = next;
++nextnext;
//if next is thelast keyframe, and not edited by the user then interpolate linearly
if (nextnext == _imp->keyFrames.end() && nextType != Natron::KEYFRAME_FREE &&
nextType != Natron::KEYFRAME_BROKEN) {
nextType = Natron::KEYFRAME_LINEAR;
}
}
double vcurDerivLeft,vcurDerivRight;
assert(key->getInterpolation() != Natron::KEYFRAME_NONE &&
key->getInterpolation() != Natron::KEYFRAME_BROKEN &&
key->getInterpolation() != Natron::KEYFRAME_FREE);
Natron::autoComputeDerivatives(prevType,
key->getInterpolation(),
nextType,
tprev, vprev,
tcur, vcur,
tnext, vnext,
vprevDerivRight,
vnextDerivLeft,
&vcurDerivLeft, &vcurDerivRight);
KeyFrame newKey(*key);
newKey.setLeftDerivative(vcurDerivLeft);
newKey.setRightDerivative(vcurDerivRight);
std::pair<KeyFrameSet::iterator,bool> newKeyIt = _imp->keyFrames.insert(newKey);
// keyframe at this time exists, erase and insert again
if (!newKeyIt.second) {
_imp->keyFrames.erase(newKeyIt.first);
newKeyIt = _imp->keyFrames.insert(newKey);
assert(newKeyIt.second);
}
key = newKeyIt.first;
if (reason != DERIVATIVES_CHANGED) {
key = evaluateCurveChanged(DERIVATIVES_CHANGED,key);
}
return key;
}