mathutils_Quaternion.c

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/*
 * $Id: mathutils_Quaternion.c 38674 2011-07-25 01:44:19Z campbellbarton $
 *
 * ***** BEGIN GPL LICENSE BLOCK *****
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * The Original Code is Copyright (C) 2001-2002 by NaN Holding BV.
 * All rights reserved.
 *
 *
 * Contributor(s): Joseph Gilbert
 *
 * ***** END GPL LICENSE BLOCK *****
 */

#include <Python.h>

#include "mathutils.h"

#include "BLI_math.h"
#include "BLI_utildefines.h"

#define QUAT_SIZE 4

static PyObject *quat__apply_to_copy(PyNoArgsFunction quat_func, QuaternionObject *self);
static PyObject *Quaternion_copy(QuaternionObject *self);

//-----------------------------METHODS------------------------------

/* note: BaseMath_ReadCallback must be called beforehand */
static PyObject *Quaternion_to_tuple_ext(QuaternionObject *self, int ndigits)
{
        PyObject *ret;
        int i;

        ret= PyTuple_New(QUAT_SIZE);

        if(ndigits >= 0) {
                for(i= 0; i < QUAT_SIZE; i++) {
                        PyTuple_SET_ITEM(ret, i, PyFloat_FromDouble(double_round((double)self->quat[i], ndigits)));
                }
        }
        else {
                for(i= 0; i < QUAT_SIZE; i++) {
                        PyTuple_SET_ITEM(ret, i, PyFloat_FromDouble(self->quat[i]));
                }
        }

        return ret;
}

PyDoc_STRVAR(Quaternion_to_euler_doc,
".. method:: to_euler(order, euler_compat)\n"
"\n"
"   Return Euler representation of the quaternion.\n"
"\n"
"   :arg order: Optional rotation order argument in\n"
"      ['XYZ', 'XZY', 'YXZ', 'YZX', 'ZXY', 'ZYX'].\n"
"   :type order: string\n"
"   :arg euler_compat: Optional euler argument the new euler will be made\n"
"      compatible with (no axis flipping between them).\n"
"      Useful for converting a series of matrices to animation curves.\n"
"   :type euler_compat: :class:`Euler`\n"
"   :return: Euler representation of the quaternion.\n"
"   :rtype: :class:`Euler`\n"
);
static PyObject *Quaternion_to_euler(QuaternionObject *self, PyObject *args)
{
        float tquat[4];
        float eul[3];
        const char *order_str= NULL;
        short order= EULER_ORDER_XYZ;
        EulerObject *eul_compat = NULL;

        if(!PyArg_ParseTuple(args, "|sO!:to_euler", &order_str, &euler_Type, &eul_compat))
                return NULL;

        if(BaseMath_ReadCallback(self) == -1)
                return NULL;

        if(order_str) {
                order= euler_order_from_string(order_str, "Matrix.to_euler()");

                if(order == -1)
                        return NULL;
        }

        normalize_qt_qt(tquat, self->quat);

        if(eul_compat) {
                float mat[3][3];

                if(BaseMath_ReadCallback(eul_compat) == -1)
                        return NULL;

                quat_to_mat3(mat, tquat);

                if(order == EULER_ORDER_XYZ)    mat3_to_compatible_eul(eul, eul_compat->eul, mat);
                else                                                    mat3_to_compatible_eulO(eul, eul_compat->eul, order, mat);
        }
        else {
                if(order == EULER_ORDER_XYZ)    quat_to_eul(eul, tquat);
                else                                                    quat_to_eulO(eul, order, tquat);
        }

        return newEulerObject(eul, order, Py_NEW, NULL);
}
//----------------------------Quaternion.toMatrix()------------------
PyDoc_STRVAR(Quaternion_to_matrix_doc,
".. method:: to_matrix()\n"
"\n"
"   Return a matrix representation of the quaternion.\n"
"\n"
"   :return: A 3x3 rotation matrix representation of the quaternion.\n"
"   :rtype: :class:`Matrix`\n"
);
static PyObject *Quaternion_to_matrix(QuaternionObject *self)
{
        float mat[9]; /* all values are set */

        if(BaseMath_ReadCallback(self) == -1)
                return NULL;

        quat_to_mat3((float (*)[3])mat, self->quat);
        return newMatrixObject(mat, 3, 3, Py_NEW, NULL);
}

//----------------------------Quaternion.cross(other)------------------
PyDoc_STRVAR(Quaternion_cross_doc,
".. method:: cross(other)\n"
"\n"
"   Return the cross product of this quaternion and another.\n"
"\n"
"   :arg other: The other quaternion to perform the cross product with.\n"
"   :type other: :class:`Quaternion`\n"
"   :return: The cross product.\n"
"   :rtype: :class:`Quaternion`\n"
);
static PyObject *Quaternion_cross(QuaternionObject *self, PyObject *value)
{
        float quat[QUAT_SIZE], tquat[QUAT_SIZE];

        if(BaseMath_ReadCallback(self) == -1)
                return NULL;

        if(mathutils_array_parse(tquat, QUAT_SIZE, QUAT_SIZE, value, "quaternion.cross(other), invalid 'other' arg") == -1)
                return NULL;

        mul_qt_qtqt(quat, self->quat, tquat);
        return newQuaternionObject(quat, Py_NEW, Py_TYPE(self));
}

//----------------------------Quaternion.dot(other)------------------
PyDoc_STRVAR(Quaternion_dot_doc,
".. method:: dot(other)\n"
"\n"
"   Return the dot product of this quaternion and another.\n"
"\n"
"   :arg other: The other quaternion to perform the dot product with.\n"
"   :type other: :class:`Quaternion`\n"
"   :return: The dot product.\n"
"   :rtype: :class:`Quaternion`\n"
);
static PyObject *Quaternion_dot(QuaternionObject *self, PyObject *value)
{
        float tquat[QUAT_SIZE];

        if(BaseMath_ReadCallback(self) == -1)
                return NULL;

        if(mathutils_array_parse(tquat, QUAT_SIZE, QUAT_SIZE, value, "quaternion.dot(other), invalid 'other' arg") == -1)
                return NULL;

        return PyFloat_FromDouble(dot_qtqt(self->quat, tquat));
}

PyDoc_STRVAR(Quaternion_rotation_difference_doc,
".. function:: difference(other)\n"
"\n"
"   Returns a quaternion representing the rotational difference.\n"
"\n"
"   :arg other: second quaternion.\n"
"   :type other: :class:`Quaternion`\n"
"   :return: the rotational difference between the two quat rotations.\n"
"   :rtype: :class:`Quaternion`\n"
);
static PyObject *Quaternion_rotation_difference(QuaternionObject *self, PyObject *value)
{
        float tquat[QUAT_SIZE], quat[QUAT_SIZE];

        if(BaseMath_ReadCallback(self) == -1)
                return NULL;

        if(mathutils_array_parse(tquat, QUAT_SIZE, QUAT_SIZE, value, "quaternion.difference(other), invalid 'other' arg") == -1)
                return NULL;

        rotation_between_quats_to_quat(quat, self->quat, tquat);

        return newQuaternionObject(quat, Py_NEW, Py_TYPE(self));
}

PyDoc_STRVAR(Quaternion_slerp_doc,
".. function:: slerp(other, factor)\n"
"\n"
"   Returns the interpolation of two quaternions.\n"
"\n"
"   :arg other: value to interpolate with.\n"
"   :type other: :class:`Quaternion`\n"
"   :arg factor: The interpolation value in [0.0, 1.0].\n"
"   :type factor: float\n"
"   :return: The interpolated rotation.\n"
"   :rtype: :class:`Quaternion`\n"
);
static PyObject *Quaternion_slerp(QuaternionObject *self, PyObject *args)
{
        PyObject *value;
        float tquat[QUAT_SIZE], quat[QUAT_SIZE], fac;

        if(!PyArg_ParseTuple(args, "Of:slerp", &value, &fac)) {
                PyErr_SetString(PyExc_TypeError,
                                "quat.slerp(): "
                                "expected Quaternion types and float");
                return NULL;
        }

        if(BaseMath_ReadCallback(self) == -1)
                return NULL;

        if(mathutils_array_parse(tquat, QUAT_SIZE, QUAT_SIZE, value, "quaternion.slerp(other), invalid 'other' arg") == -1)
                return NULL;

        if(fac > 1.0f || fac < 0.0f) {
                PyErr_SetString(PyExc_ValueError,
                                "quat.slerp(): "
                                "interpolation factor must be between 0.0 and 1.0");
                return NULL;
        }

        interp_qt_qtqt(quat, self->quat, tquat, fac);

        return newQuaternionObject(quat, Py_NEW, Py_TYPE(self));
}

PyDoc_STRVAR(Quaternion_rotate_doc,
".. method:: rotate(other)\n"
"\n"
"   Rotates the quaternion a by another mathutils value.\n"
"\n"
"   :arg other: rotation component of mathutils value\n"
"   :type other: :class:`Euler`, :class:`Quaternion` or :class:`Matrix`\n"
);
static PyObject *Quaternion_rotate(QuaternionObject *self, PyObject *value)
{
        float self_rmat[3][3], other_rmat[3][3], rmat[3][3];
        float tquat[4], length;

        if(BaseMath_ReadCallback(self) == -1)
                return NULL;

        if(mathutils_any_to_rotmat(other_rmat, value, "quaternion.rotate(value)") == -1)
                return NULL;

        length= normalize_qt_qt(tquat, self->quat);
        quat_to_mat3(self_rmat, tquat);
        mul_m3_m3m3(rmat, self_rmat, other_rmat);

        mat3_to_quat(self->quat, rmat);
        mul_qt_fl(self->quat, length); /* maintain length after rotating */

        (void)BaseMath_WriteCallback(self);
        Py_RETURN_NONE;
}

//----------------------------Quaternion.normalize()----------------
//normalize the axis of rotation of [theta, vector]
PyDoc_STRVAR(Quaternion_normalize_doc,
".. function:: normalize()\n"
"\n"
"   Normalize the quaternion.\n"
);
static PyObject *Quaternion_normalize(QuaternionObject *self)
{
        if(BaseMath_ReadCallback(self) == -1)
                return NULL;

        normalize_qt(self->quat);

        (void)BaseMath_WriteCallback(self);
        Py_RETURN_NONE;
}
PyDoc_STRVAR(Quaternion_normalized_doc,
".. function:: normalized()\n"
"\n"
"   Return a new normalized quaternion.\n"
"\n"
"   :return: a normalized copy.\n"
"   :rtype: :class:`Quaternion`\n"
);
static PyObject *Quaternion_normalized(QuaternionObject *self)
{
        return quat__apply_to_copy((PyNoArgsFunction)Quaternion_normalize, self);
}

//----------------------------Quaternion.invert()------------------
PyDoc_STRVAR(Quaternion_invert_doc,
".. function:: invert()\n"
"\n"
"   Set the quaternion to its inverse.\n"
);
static PyObject *Quaternion_invert(QuaternionObject *self)
{
        if(BaseMath_ReadCallback(self) == -1)
                return NULL;

        invert_qt(self->quat);

        (void)BaseMath_WriteCallback(self);
        Py_RETURN_NONE;
}
PyDoc_STRVAR(Quaternion_inverted_doc,
".. function:: inverted()\n"
"\n"
"   Return a new, inverted quaternion.\n"
"\n"
"   :return: the inverted value.\n"
"   :rtype: :class:`Quaternion`\n"
);
static PyObject *Quaternion_inverted(QuaternionObject *self)
{
        return quat__apply_to_copy((PyNoArgsFunction)Quaternion_invert, self);
}

//----------------------------Quaternion.identity()-----------------
PyDoc_STRVAR(Quaternion_identity_doc,
".. function:: identity()\n"
"\n"
"   Set the quaternion to an identity quaternion.\n"
"\n"
"   :return: an instance of itself.\n"
"   :rtype: :class:`Quaternion`\n"
);
static PyObject *Quaternion_identity(QuaternionObject *self)
{
        if(BaseMath_ReadCallback(self) == -1)
                return NULL;

        unit_qt(self->quat);

        (void)BaseMath_WriteCallback(self);
        Py_RETURN_NONE;
}
//----------------------------Quaternion.negate()-------------------
PyDoc_STRVAR(Quaternion_negate_doc,
".. function:: negate()\n"
"\n"
"   Set the quaternion to its negative.\n"
"\n"
"   :return: an instance of itself.\n"
"   :rtype: :class:`Quaternion`\n"
);
static PyObject *Quaternion_negate(QuaternionObject *self)
{
        if(BaseMath_ReadCallback(self) == -1)
                return NULL;

        mul_qt_fl(self->quat, -1.0f);

        (void)BaseMath_WriteCallback(self);
        Py_RETURN_NONE;
}
//----------------------------Quaternion.conjugate()----------------
PyDoc_STRVAR(Quaternion_conjugate_doc,
".. function:: conjugate()\n"
"\n"
"   Set the quaternion to its conjugate (negate x, y, z).\n"
);
static PyObject *Quaternion_conjugate(QuaternionObject *self)
{
        if(BaseMath_ReadCallback(self) == -1)
                return NULL;

        conjugate_qt(self->quat);

        (void)BaseMath_WriteCallback(self);
        Py_RETURN_NONE;
}
PyDoc_STRVAR(Quaternion_conjugated_doc,
".. function:: conjugated()\n"
"\n"
"   Return a new conjugated quaternion.\n"
"\n"
"   :return: a new quaternion.\n"
"   :rtype: :class:`Quaternion`\n"
);
static PyObject *Quaternion_conjugated(QuaternionObject *self)
{
        return quat__apply_to_copy((PyNoArgsFunction)Quaternion_conjugate, self);
}

//----------------------------Quaternion.copy()----------------
PyDoc_STRVAR(Quaternion_copy_doc,
".. function:: copy()\n"
"\n"
"   Returns a copy of this quaternion.\n"
"\n"
"   :return: A copy of the quaternion.\n"
"   :rtype: :class:`Quaternion`\n"
"\n"
"   .. note:: use this to get a copy of a wrapped quaternion with\n"
"      no reference to the original data.\n"
);
static PyObject *Quaternion_copy(QuaternionObject *self)
{
        if(BaseMath_ReadCallback(self) == -1)
                return NULL;

        return newQuaternionObject(self->quat, Py_NEW, Py_TYPE(self));
}

//----------------------------print object (internal)--------------
//print the object to screen
static PyObject *Quaternion_repr(QuaternionObject *self)
{
        PyObject *ret, *tuple;

        if(BaseMath_ReadCallback(self) == -1)
                return NULL;

        tuple= Quaternion_to_tuple_ext(self, -1);

        ret= PyUnicode_FromFormat("Quaternion(%R)", tuple);

        Py_DECREF(tuple);
        return ret;
}

static PyObject* Quaternion_richcmpr(PyObject *a, PyObject *b, int op)
{
        PyObject *res;
        int ok= -1; /* zero is true */

        if (QuaternionObject_Check(a) && QuaternionObject_Check(b)) {
                QuaternionObject *quatA= (QuaternionObject *)a;
                QuaternionObject *quatB= (QuaternionObject *)b;

                if(BaseMath_ReadCallback(quatA) == -1 || BaseMath_ReadCallback(quatB) == -1)
                        return NULL;

                ok= (EXPP_VectorsAreEqual(quatA->quat, quatB->quat, QUAT_SIZE, 1)) ? 0 : -1;
        }

        switch (op) {
        case Py_NE:
                ok = !ok; /* pass through */
        case Py_EQ:
                res = ok ? Py_False : Py_True;
                break;

        case Py_LT:
        case Py_LE:
        case Py_GT:
        case Py_GE:
                res = Py_NotImplemented;
                break;
        default:
                PyErr_BadArgument();
                return NULL;
        }

        return Py_INCREF(res), res;
}

//---------------------SEQUENCE PROTOCOLS------------------------
//----------------------------len(object)------------------------
//sequence length
static int Quaternion_len(QuaternionObject *UNUSED(self))
{
        return QUAT_SIZE;
}
//----------------------------object[]---------------------------
//sequence accessor (get)
static PyObject *Quaternion_item(QuaternionObject *self, int i)
{
        if(i<0) i= QUAT_SIZE-i;

        if(i < 0 || i >= QUAT_SIZE) {
                PyErr_SetString(PyExc_IndexError,
                                "quaternion[attribute]: "
                                "array index out of range");
                return NULL;
        }

        if(BaseMath_ReadIndexCallback(self, i) == -1)
                return NULL;

        return PyFloat_FromDouble(self->quat[i]);

}
//----------------------------object[]-------------------------
//sequence accessor (set)
static int Quaternion_ass_item(QuaternionObject *self, int i, PyObject *ob)
{
        float scalar= (float)PyFloat_AsDouble(ob);
        if(scalar==-1.0f && PyErr_Occurred()) { /* parsed item not a number */
                PyErr_SetString(PyExc_TypeError,
                                "quaternion[index] = x: "
                                "index argument not a number");
                return -1;
        }

        if(i<0) i= QUAT_SIZE-i;

        if(i < 0 || i >= QUAT_SIZE){
                PyErr_SetString(PyExc_IndexError,
                                "quaternion[attribute] = x: "
                                "array assignment index out of range");
                return -1;
        }
        self->quat[i] = scalar;

        if(BaseMath_WriteIndexCallback(self, i) == -1)
                return -1;

        return 0;
}
//----------------------------object[z:y]------------------------
//sequence slice (get)
static PyObject *Quaternion_slice(QuaternionObject *self, int begin, int end)
{
        PyObject *tuple;
        int count;

        if(BaseMath_ReadCallback(self) == -1)
                return NULL;

        CLAMP(begin, 0, QUAT_SIZE);
        if (end<0) end= (QUAT_SIZE + 1) + end;
        CLAMP(end, 0, QUAT_SIZE);
        begin= MIN2(begin, end);

        tuple= PyTuple_New(end - begin);
        for(count= begin; count < end; count++) {
                PyTuple_SET_ITEM(tuple, count - begin, PyFloat_FromDouble(self->quat[count]));
        }

        return tuple;
}
//----------------------------object[z:y]------------------------
//sequence slice (set)
static int Quaternion_ass_slice(QuaternionObject *self, int begin, int end, PyObject *seq)
{
        int i, size;
        float quat[QUAT_SIZE];

        if(BaseMath_ReadCallback(self) == -1)
                return -1;

        CLAMP(begin, 0, QUAT_SIZE);
        if (end<0) end= (QUAT_SIZE + 1) + end;
        CLAMP(end, 0, QUAT_SIZE);
        begin = MIN2(begin, end);

        if((size=mathutils_array_parse(quat, 0, QUAT_SIZE, seq, "mathutils.Quaternion[begin:end] = []")) == -1)
                return -1;

        if(size != (end - begin)){
                PyErr_SetString(PyExc_ValueError,
                                "quaternion[begin:end] = []: "
                                "size mismatch in slice assignment");
                return -1;
        }

        /* parsed well - now set in vector */
        for(i= 0; i < size; i++)
                self->quat[begin + i] = quat[i];

        (void)BaseMath_WriteCallback(self);
        return 0;
}


static PyObject *Quaternion_subscript(QuaternionObject *self, PyObject *item)
{
        if (PyIndex_Check(item)) {
                Py_ssize_t i;
                i = PyNumber_AsSsize_t(item, PyExc_IndexError);
                if (i == -1 && PyErr_Occurred())
                        return NULL;
                if (i < 0)
                        i += QUAT_SIZE;
                return Quaternion_item(self, i);
        } else if (PySlice_Check(item)) {
                Py_ssize_t start, stop, step, slicelength;

                if (PySlice_GetIndicesEx((void *)item, QUAT_SIZE, &start, &stop, &step, &slicelength) < 0)
                        return NULL;

                if (slicelength <= 0) {
                        return PyTuple_New(0);
                }
                else if (step == 1) {
                        return Quaternion_slice(self, start, stop);
                }
                else {
                        PyErr_SetString(PyExc_IndexError,
                                        "slice steps not supported with quaternions");
                        return NULL;
                }
        }
        else {
                PyErr_Format(PyExc_TypeError,
                             "quaternion indices must be integers, not %.200s",
                             Py_TYPE(item)->tp_name);
                return NULL;
        }
}


static int Quaternion_ass_subscript(QuaternionObject *self, PyObject *item, PyObject *value)
{
        if (PyIndex_Check(item)) {
                Py_ssize_t i = PyNumber_AsSsize_t(item, PyExc_IndexError);
                if (i == -1 && PyErr_Occurred())
                        return -1;
                if (i < 0)
                        i += QUAT_SIZE;
                return Quaternion_ass_item(self, i, value);
        }
        else if (PySlice_Check(item)) {
                Py_ssize_t start, stop, step, slicelength;

                if (PySlice_GetIndicesEx((void *)item, QUAT_SIZE, &start, &stop, &step, &slicelength) < 0)
                        return -1;

                if (step == 1)
                        return Quaternion_ass_slice(self, start, stop, value);
                else {
                        PyErr_SetString(PyExc_IndexError,
                                        "slice steps not supported with quaternion");
                        return -1;
                }
        }
        else {
                PyErr_Format(PyExc_TypeError,
                             "quaternion indices must be integers, not %.200s",
                             Py_TYPE(item)->tp_name);
                return -1;
        }
}

//------------------------NUMERIC PROTOCOLS----------------------
//------------------------obj + obj------------------------------
//addition
static PyObject *Quaternion_add(PyObject *q1, PyObject *q2)
{
        float quat[QUAT_SIZE];
        QuaternionObject *quat1 = NULL, *quat2 = NULL;

        if(!QuaternionObject_Check(q1) || !QuaternionObject_Check(q2)) {
                PyErr_SetString(PyExc_TypeError,
                                "Quaternion addition: "
                                "arguments not valid for this operation");
                return NULL;
        }
        quat1 = (QuaternionObject*)q1;
        quat2 = (QuaternionObject*)q2;

        if(BaseMath_ReadCallback(quat1) == -1 || BaseMath_ReadCallback(quat2) == -1)
                return NULL;

        add_qt_qtqt(quat, quat1->quat, quat2->quat, 1.0f);
        return newQuaternionObject(quat, Py_NEW, Py_TYPE(q1));
}
//------------------------obj - obj------------------------------
//subtraction
static PyObject *Quaternion_sub(PyObject *q1, PyObject *q2)
{
        int x;
        float quat[QUAT_SIZE];
        QuaternionObject *quat1 = NULL, *quat2 = NULL;

        if(!QuaternionObject_Check(q1) || !QuaternionObject_Check(q2)) {
                PyErr_SetString(PyExc_TypeError,
                                "Quaternion addition: "
                                "arguments not valid for this operation");
                return NULL;
        }

        quat1 = (QuaternionObject*)q1;
        quat2 = (QuaternionObject*)q2;

        if(BaseMath_ReadCallback(quat1) == -1 || BaseMath_ReadCallback(quat2) == -1)
                return NULL;

        for(x = 0; x < QUAT_SIZE; x++) {
                quat[x] = quat1->quat[x] - quat2->quat[x];
        }

        return newQuaternionObject(quat, Py_NEW, Py_TYPE(q1));
}

static PyObject *quat_mul_float(QuaternionObject *quat, const float scalar)
{
        float tquat[4];
        copy_qt_qt(tquat, quat->quat);
        mul_qt_fl(tquat, scalar);
        return newQuaternionObject(tquat, Py_NEW, Py_TYPE(quat));
}

//------------------------obj * obj------------------------------
//mulplication
static PyObject *Quaternion_mul(PyObject *q1, PyObject *q2)
{
        float quat[QUAT_SIZE], scalar;
        QuaternionObject *quat1 = NULL, *quat2 = NULL;

        if(QuaternionObject_Check(q1)) {
                quat1 = (QuaternionObject*)q1;
                if(BaseMath_ReadCallback(quat1) == -1)
                        return NULL;
        }
        if(QuaternionObject_Check(q2)) {
                quat2 = (QuaternionObject*)q2;
                if(BaseMath_ReadCallback(quat2) == -1)
                        return NULL;
        }

        if(quat1 && quat2) { /* QUAT*QUAT (cross product) */
                mul_qt_qtqt(quat, quat1->quat, quat2->quat);
                return newQuaternionObject(quat, Py_NEW, Py_TYPE(q1));
        }
        /* the only case this can happen (for a supported type is "FLOAT*QUAT") */
        else if(quat2) { /* FLOAT*QUAT */
                if(((scalar= PyFloat_AsDouble(q1)) == -1.0f && PyErr_Occurred())==0) {
                        return quat_mul_float(quat2, scalar);
                }
        }
        else if (quat1) {
                /* QUAT * VEC */
                if (VectorObject_Check(q2)) {
                        VectorObject *vec2 = (VectorObject *)q2;
                        float tvec[3];

                        if(vec2->size != 3) {
                                PyErr_SetString(PyExc_ValueError,
                                                                "Vector multiplication: "
                                                                "only 3D vector rotations (with quats) "
                                                "currently supported");
                                return NULL;
                        }
                        if(BaseMath_ReadCallback(vec2) == -1) {
                                return NULL;
                        }

                        copy_v3_v3(tvec, vec2->vec);
                        mul_qt_v3(quat1->quat, tvec);

                        return newVectorObject(tvec, 3, Py_NEW, Py_TYPE(vec2));
                }
                /* QUAT * FLOAT */
                else if((((scalar= PyFloat_AsDouble(q2)) == -1.0f && PyErr_Occurred())==0)) {
                        return quat_mul_float(quat1, scalar);
                }
        }
        else {
                BLI_assert(!"internal error");
        }

        PyErr_Format(PyExc_TypeError,
                     "Quaternion multiplication: "
                     "not supported between '%.200s' and '%.200s' types",
                     Py_TYPE(q1)->tp_name, Py_TYPE(q2)->tp_name);
        return NULL;
}

/* -obj
  returns the negative of this object*/
static PyObject *Quaternion_neg(QuaternionObject *self)
{
        float tquat[QUAT_SIZE];

        if(BaseMath_ReadCallback(self) == -1)
                return NULL;

        negate_v4_v4(tquat, self->quat);
        return newQuaternionObject(tquat, Py_NEW, Py_TYPE(self));
}


//-----------------PROTOCOL DECLARATIONS--------------------------
static PySequenceMethods Quaternion_SeqMethods = {
        (lenfunc) Quaternion_len,                               /* sq_length */
        (binaryfunc) NULL,                                              /* sq_concat */
        (ssizeargfunc) NULL,                                    /* sq_repeat */
        (ssizeargfunc) Quaternion_item,                 /* sq_item */
        (ssizessizeargfunc) NULL,                               /* sq_slice, deprecated */
        (ssizeobjargproc) Quaternion_ass_item,  /* sq_ass_item */
        (ssizessizeobjargproc) NULL,                    /* sq_ass_slice, deprecated */
        (objobjproc) NULL,                                              /* sq_contains */
        (binaryfunc) NULL,                                              /* sq_inplace_concat */
        (ssizeargfunc) NULL,                                    /* sq_inplace_repeat */
};

static PyMappingMethods Quaternion_AsMapping = {
        (lenfunc)Quaternion_len,
        (binaryfunc)Quaternion_subscript,
        (objobjargproc)Quaternion_ass_subscript
};

static PyNumberMethods Quaternion_NumMethods = {
        (binaryfunc)    Quaternion_add, /*nb_add*/
        (binaryfunc)    Quaternion_sub, /*nb_subtract*/
        (binaryfunc)    Quaternion_mul, /*nb_multiply*/
        NULL,                                                   /*nb_remainder*/
        NULL,                                                   /*nb_divmod*/
        NULL,                                                   /*nb_power*/
        (unaryfunc)     Quaternion_neg, /*nb_negative*/
        (unaryfunc)     0,      /*tp_positive*/
        (unaryfunc)     0,      /*tp_absolute*/
        (inquiry)       0,      /*tp_bool*/
        (unaryfunc)     0,      /*nb_invert*/
        NULL,                           /*nb_lshift*/
        (binaryfunc)0,  /*nb_rshift*/
        NULL,                           /*nb_and*/
        NULL,                           /*nb_xor*/
        NULL,                           /*nb_or*/
        NULL,                           /*nb_int*/
        NULL,                           /*nb_reserved*/
        NULL,                           /*nb_float*/
        NULL,                           /* nb_inplace_add */
        NULL,                           /* nb_inplace_subtract */
        NULL,                           /* nb_inplace_multiply */
        NULL,                           /* nb_inplace_remainder */
        NULL,                           /* nb_inplace_power */
        NULL,                           /* nb_inplace_lshift */
        NULL,                           /* nb_inplace_rshift */
        NULL,                           /* nb_inplace_and */
        NULL,                           /* nb_inplace_xor */
        NULL,                           /* nb_inplace_or */
        NULL,                           /* nb_floor_divide */
        NULL,                           /* nb_true_divide */
        NULL,                           /* nb_inplace_floor_divide */
        NULL,                           /* nb_inplace_true_divide */
        NULL,                           /* nb_index */
};

static PyObject *Quaternion_getAxis(QuaternionObject *self, void *type)
{
        return Quaternion_item(self, GET_INT_FROM_POINTER(type));
}

static int Quaternion_setAxis(QuaternionObject *self, PyObject *value, void *type)
{
        return Quaternion_ass_item(self, GET_INT_FROM_POINTER(type), value);
}

static PyObject *Quaternion_getMagnitude(QuaternionObject *self, void *UNUSED(closure))
{
        if(BaseMath_ReadCallback(self) == -1)
                return NULL;

        return PyFloat_FromDouble(sqrt(dot_qtqt(self->quat, self->quat)));
}

static PyObject *Quaternion_getAngle(QuaternionObject *self, void *UNUSED(closure))
{
        float tquat[4];

        if(BaseMath_ReadCallback(self) == -1)
                return NULL;

        normalize_qt_qt(tquat, self->quat);
        return PyFloat_FromDouble(2.0f * (saacos(tquat[0])));
}

static int Quaternion_setAngle(QuaternionObject *self, PyObject *value, void *UNUSED(closure))
{
        float tquat[4];
        float len;

        float axis[3], angle_dummy;
        double angle;

        if(BaseMath_ReadCallback(self) == -1)
                return -1;

        len= normalize_qt_qt(tquat, self->quat);
        quat_to_axis_angle(axis, &angle_dummy, tquat);

        angle= PyFloat_AsDouble(value);

        if(angle==-1.0 && PyErr_Occurred()) { /* parsed item not a number */
                PyErr_SetString(PyExc_TypeError,
                                "quaternion.angle = value: float expected");
                return -1;
        }

        angle= angle_wrap_rad(angle);

        /* If the axis of rotation is 0,0,0 set it to 1,0,0 - for zero-degree rotations */
        if(     EXPP_FloatsAreEqual(axis[0], 0.0f, 10) &&
                EXPP_FloatsAreEqual(axis[1], 0.0f, 10) &&
                EXPP_FloatsAreEqual(axis[2], 0.0f, 10)
        ) {
                axis[0] = 1.0f;
        }

        axis_angle_to_quat(self->quat, axis, angle);
        mul_qt_fl(self->quat, len);

        if(BaseMath_WriteCallback(self) == -1)
                return -1;

        return 0;
}

static PyObject *Quaternion_getAxisVec(QuaternionObject *self, void *UNUSED(closure))
{
        float tquat[4];

        float axis[3];
        float angle;

        if(BaseMath_ReadCallback(self) == -1)
                return NULL;

        normalize_qt_qt(tquat, self->quat);
        quat_to_axis_angle(axis, &angle, tquat);

        /* If the axis of rotation is 0,0,0 set it to 1,0,0 - for zero-degree rotations */
        if(     EXPP_FloatsAreEqual(axis[0], 0.0f, 10) &&
                EXPP_FloatsAreEqual(axis[1], 0.0f, 10) &&
                EXPP_FloatsAreEqual(axis[2], 0.0f, 10)
        ) {
                axis[0] = 1.0f;
        }

        return (PyObject *) newVectorObject(axis, 3, Py_NEW, NULL);
}

static int Quaternion_setAxisVec(QuaternionObject *self, PyObject *value, void *UNUSED(closure))
{
        float tquat[4];
        float len;

        float axis[3];
        float angle;

        if(BaseMath_ReadCallback(self) == -1)
                return -1;

        len= normalize_qt_qt(tquat, self->quat);
        quat_to_axis_angle(axis, &angle, tquat); /* axis value is unused */

        if (mathutils_array_parse(axis, 3, 3, value, "quat.axis = other") == -1)
                return -1;

        axis_angle_to_quat(self->quat, axis, angle);
        mul_qt_fl(self->quat, len);

        if(BaseMath_WriteCallback(self) == -1)
                return -1;

        return 0;
}

//----------------------------------mathutils.Quaternion() --------------
static PyObject *Quaternion_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
{
        PyObject *seq= NULL;
        double angle = 0.0f;
        float quat[QUAT_SIZE]= {0.0f, 0.0f, 0.0f, 0.0f};

        if(kwds && PyDict_Size(kwds)) {
                PyErr_SetString(PyExc_TypeError,
                                "mathutils.Quaternion(): "
                                "takes no keyword args");
                return NULL;
        }

        if(!PyArg_ParseTuple(args, "|Od:mathutils.Quaternion", &seq, &angle))
                return NULL;

        switch(PyTuple_GET_SIZE(args)) {
        case 0:
                break;
        case 1:
                if (mathutils_array_parse(quat, QUAT_SIZE, QUAT_SIZE, seq, "mathutils.Quaternion()") == -1)
                        return NULL;
                break;
        case 2:
                if (mathutils_array_parse(quat, 3, 3, seq, "mathutils.Quaternion()") == -1)
                        return NULL;
                angle= angle_wrap_rad(angle); /* clamp because of precision issues */
                axis_angle_to_quat(quat, quat, angle);
                break;
        /* PyArg_ParseTuple assures no more then 2 */
        }
        return newQuaternionObject(quat, Py_NEW, type);
}

static PyObject *quat__apply_to_copy(PyNoArgsFunction quat_func, QuaternionObject *self)
{
        PyObject *ret= Quaternion_copy(self);
        PyObject *ret_dummy= quat_func(ret);
        if(ret_dummy) {
                Py_DECREF(ret_dummy);
                return (PyObject *)ret;
        }
        else { /* error */
                Py_DECREF(ret);
                return NULL;
        }
}

//-----------------------METHOD DEFINITIONS ----------------------
static struct PyMethodDef Quaternion_methods[] = {
        /* in place only */
        {"identity", (PyCFunction) Quaternion_identity, METH_NOARGS, Quaternion_identity_doc},
        {"negate", (PyCFunction) Quaternion_negate, METH_NOARGS, Quaternion_negate_doc},

        /* operate on original or copy */
        {"conjugate", (PyCFunction) Quaternion_conjugate, METH_NOARGS, Quaternion_conjugate_doc},
        {"conjugated", (PyCFunction) Quaternion_conjugated, METH_NOARGS, Quaternion_conjugated_doc},

        {"invert", (PyCFunction) Quaternion_invert, METH_NOARGS, Quaternion_invert_doc},
        {"inverted", (PyCFunction) Quaternion_inverted, METH_NOARGS, Quaternion_inverted_doc},

        {"normalize", (PyCFunction) Quaternion_normalize, METH_NOARGS, Quaternion_normalize_doc},
        {"normalized", (PyCFunction) Quaternion_normalized, METH_NOARGS, Quaternion_normalized_doc},

        /* return converted representation */
        {"to_euler", (PyCFunction) Quaternion_to_euler, METH_VARARGS, Quaternion_to_euler_doc},
        {"to_matrix", (PyCFunction) Quaternion_to_matrix, METH_NOARGS, Quaternion_to_matrix_doc},

        /* operation between 2 or more types  */
        {"cross", (PyCFunction) Quaternion_cross, METH_O, Quaternion_cross_doc},
        {"dot", (PyCFunction) Quaternion_dot, METH_O, Quaternion_dot_doc},
        {"rotation_difference", (PyCFunction) Quaternion_rotation_difference, METH_O, Quaternion_rotation_difference_doc},
        {"slerp", (PyCFunction) Quaternion_slerp, METH_VARARGS, Quaternion_slerp_doc},
        {"rotate", (PyCFunction) Quaternion_rotate, METH_O, Quaternion_rotate_doc},

        {"__copy__", (PyCFunction) Quaternion_copy, METH_NOARGS, Quaternion_copy_doc},
        {"copy", (PyCFunction) Quaternion_copy, METH_NOARGS, Quaternion_copy_doc},
        {NULL, NULL, 0, NULL}
};

/*****************************************************************************/
/* Python attributes get/set structure:                                      */
/*****************************************************************************/
static PyGetSetDef Quaternion_getseters[] = {
        {(char *)"w", (getter)Quaternion_getAxis, (setter)Quaternion_setAxis, (char *)"Quaternion W value.\n\n:type: float", (void *)0},
        {(char *)"x", (getter)Quaternion_getAxis, (setter)Quaternion_setAxis, (char *)"Quaternion X axis.\n\n:type: float", (void *)1},
        {(char *)"y", (getter)Quaternion_getAxis, (setter)Quaternion_setAxis, (char *)"Quaternion Y axis.\n\n:type: float", (void *)2},
        {(char *)"z", (getter)Quaternion_getAxis, (setter)Quaternion_setAxis, (char *)"Quaternion Z axis.\n\n:type: float", (void *)3},
        {(char *)"magnitude", (getter)Quaternion_getMagnitude, (setter)NULL, (char *)"Size of the quaternion (readonly).\n\n:type: float", NULL},
        {(char *)"angle", (getter)Quaternion_getAngle, (setter)Quaternion_setAngle, (char *)"angle of the quaternion.\n\n:type: float", NULL},
        {(char *)"axis",(getter)Quaternion_getAxisVec, (setter)Quaternion_setAxisVec, (char *)"quaternion axis as a vector.\n\n:type: :class:`Vector`", NULL},
        {(char *)"is_wrapped", (getter)BaseMathObject_getWrapped, (setter)NULL, (char *)BaseMathObject_Wrapped_doc, NULL},
        {(char *)"owner", (getter)BaseMathObject_getOwner, (setter)NULL, (char *)BaseMathObject_Owner_doc, NULL},
        {NULL, NULL, NULL, NULL, NULL}  /* Sentinel */
};

//------------------PY_OBECT DEFINITION--------------------------
PyDoc_STRVAR(quaternion_doc,
"This object gives access to Quaternions in Blender."
);
PyTypeObject quaternion_Type = {
        PyVarObject_HEAD_INIT(NULL, 0)
        "mathutils.Quaternion",                                         //tp_name
        sizeof(QuaternionObject),                       //tp_basicsize
        0,                                                              //tp_itemsize
        (destructor)BaseMathObject_dealloc,             //tp_dealloc
        NULL,                                                           //tp_print
        NULL,                                                           //tp_getattr
        NULL,                                                           //tp_setattr
        NULL,                                                           //tp_compare
        (reprfunc) Quaternion_repr,             //tp_repr
        &Quaternion_NumMethods,                 //tp_as_number
        &Quaternion_SeqMethods,                 //tp_as_sequence
        &Quaternion_AsMapping,                  //tp_as_mapping
        NULL,                                                           //tp_hash
        NULL,                                                           //tp_call
        NULL,                                                           //tp_str
        NULL,                                                           //tp_getattro
        NULL,                                                           //tp_setattro
        NULL,                                                           //tp_as_buffer
        Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE | Py_TPFLAGS_HAVE_GC, //tp_flags
        quaternion_doc, //tp_doc
        (traverseproc)BaseMathObject_traverse,  //tp_traverse
        (inquiry)BaseMathObject_clear,  //tp_clear
        (richcmpfunc)Quaternion_richcmpr,       //tp_richcompare
        0,                                                              //tp_weaklistoffset
        NULL,                                                           //tp_iter
        NULL,                                                           //tp_iternext
        Quaternion_methods,                             //tp_methods
        NULL,                                                           //tp_members
        Quaternion_getseters,                   //tp_getset
        NULL,                                                           //tp_base
        NULL,                                                           //tp_dict
        NULL,                                                           //tp_descr_get
        NULL,                                                           //tp_descr_set
        0,                                                              //tp_dictoffset
        NULL,                                                           //tp_init
        NULL,                                                           //tp_alloc
        Quaternion_new,                                 //tp_new
        NULL,                                                           //tp_free
        NULL,                                                           //tp_is_gc
        NULL,                                                           //tp_bases
        NULL,                                                           //tp_mro
        NULL,                                                           //tp_cache
        NULL,                                                           //tp_subclasses
        NULL,                                                           //tp_weaklist
        NULL,                                                           //tp_del
};
//------------------------newQuaternionObject (internal)-------------
//creates a new quaternion object
/*pass Py_WRAP - if vector is a WRAPPER for data allocated by BLENDER
 (i.e. it was allocated elsewhere by MEM_mallocN())
  pass Py_NEW - if vector is not a WRAPPER and managed by PYTHON
 (i.e. it must be created here with PyMEM_malloc())*/
PyObject *newQuaternionObject(float *quat, int type, PyTypeObject *base_type)
{
        QuaternionObject *self;

        self= base_type ?       (QuaternionObject *)base_type->tp_alloc(base_type, 0) :
                                                (QuaternionObject *)PyObject_GC_New(QuaternionObject, &quaternion_Type);

        if(self) {
                /* init callbacks as NULL */
                self->cb_user= NULL;
                self->cb_type= self->cb_subtype= 0;

                if(type == Py_WRAP){
                        self->quat = quat;
                        self->wrapped = Py_WRAP;
                }
                else if (type == Py_NEW){
                        self->quat = PyMem_Malloc(QUAT_SIZE * sizeof(float));
                        if(!quat) { //new empty
                                unit_qt(self->quat);
                        }
                        else {
                                QUATCOPY(self->quat, quat);
                        }
                        self->wrapped = Py_NEW;
                }
                else {
                        Py_FatalError("Quaternion(): invalid type!");
                }
        }
        return (PyObject *) self;
}

PyObject *newQuaternionObject_cb(PyObject *cb_user, int cb_type, int cb_subtype)
{
        QuaternionObject *self= (QuaternionObject *)newQuaternionObject(NULL, Py_NEW, NULL);
        if(self) {
                Py_INCREF(cb_user);
                self->cb_user=                  cb_user;
                self->cb_type=                  (unsigned char)cb_type;
                self->cb_subtype=               (unsigned char)cb_subtype;
                PyObject_GC_Track(self);
        }

        return (PyObject *)self;
}