void n_tentacle::computeSlerp(const MMatrix &matrix1, const MMatrix &matrix2, const MFnNurbsCurve &curve, double parameter, double blendRot, double iniLength, double curveLength, double stretch, double globalScale, int tangentAxis, MVector &outPos, MVector &outRot) { //curveLength = curve.length() double lenRatio = iniLength / curveLength; MQuaternion quat1; quat1 = matrix1; MQuaternion quat2; quat2 = matrix2; this->bipolarityCheck(quat1, quat2); //need to adjust the parameter in order to maintain the length between elements, also for the stretch MVector tangent; MPoint pointAtParam; MPoint finaPos; double p = lenRatio * parameter * globalScale; double finalParam = p + (parameter - p) * stretch; if(curveLength * finalParam > curveLength) { double lengthDiff = curveLength - (iniLength * parameter); double param = curve.knot(curve.numKnots() - 1); tangent = curve.tangent(param, MSpace::kWorld); tangent.normalize(); curve.getPointAtParam(param, pointAtParam, MSpace::kWorld); finaPos = pointAtParam; pointAtParam += (- tangent) * lengthDiff; //MGlobal::displayInfo("sdf"); } else { double param = curve.findParamFromLength(curveLength * finalParam); tangent = curve.tangent(param, MSpace::kWorld); tangent.normalize(); curve.getPointAtParam(param, pointAtParam, MSpace::kWorld); } MQuaternion slerpQuat = slerp(quat1, quat2, blendRot); MMatrix slerpMatrix = slerpQuat.asMatrix(); int axisId = abs(tangentAxis) - 1; MVector slerpMatrixYAxis = MVector(slerpMatrix(axisId, 0), slerpMatrix(axisId, 1), slerpMatrix(axisId, 2)); slerpMatrixYAxis.normalize(); if(tangentAxis < 0) slerpMatrixYAxis = - slerpMatrixYAxis; double angle = tangent.angle(slerpMatrixYAxis); MVector axis = slerpMatrixYAxis ^ tangent; axis.normalize(); MQuaternion rotationToSnapOnCurve(angle, axis); MQuaternion finalQuat = slerpQuat * rotationToSnapOnCurve; MEulerRotation finalEuler = finalQuat.asEulerRotation(); outRot.x = finalEuler.x; outRot.y = finalEuler.y; outRot.z = finalEuler.z; outPos = pointAtParam; }