path: root/redist/linmath.c

// Copyright 2013,2016 <>< C. N. Lohr.  This file licensed under the terms of the MIT license.

#include "linmath.h"
#include <float.h>
#include <math.h>
#include <string.h>

inline void cross3d(FLT *out, const FLT *a, const FLT *b) {
	out[0] = a[1] * b[2] - a[2] * b[1];
	out[1] = a[2] * b[0] - a[0] * b[2];
	out[2] = a[0] * b[1] - a[1] * b[0];
}

inline void sub3d(FLT *out, const FLT *a, const FLT *b) {
	out[0] = a[0] - b[0];
	out[1] = a[1] - b[1];
	out[2] = a[2] - b[2];
}

inline void add3d(FLT *out, const FLT *a, const FLT *b) {
	out[0] = a[0] + b[0];
	out[1] = a[1] + b[1];
	out[2] = a[2] + b[2];
}

inline void scale3d(FLT *out, const FLT *a, FLT scalar) {
	out[0] = a[0] * scalar;
	out[1] = a[1] * scalar;
	out[2] = a[2] * scalar;
}

inline void normalize3d(FLT *out, const FLT *in) {
	FLT r = ((FLT)1.) / FLT_SQRT(in[0] * in[0] + in[1] * in[1] + in[2] * in[2]);
	out[0] = in[0] * r;
	out[1] = in[1] * r;
	out[2] = in[2] * r;
}

FLT dot3d(const FLT *a, const FLT *b) { return a[0] * b[0] + a[1] * b[1] + a[2] * b[2]; }

int compare3d(const FLT *a, const FLT *b, FLT epsilon) {
	if (!a || !b)
		return 0;
	if (a[2] - b[2] > epsilon)
		return 1;
	if (b[2] - a[2] > epsilon)
		return -1;
	if (a[1] - b[1] > epsilon)
		return 1;
	if (b[1] - a[1] > epsilon)
		return -1;
	if (a[0] - b[0] > epsilon)
		return 1;
	if (b[0] - a[0] > epsilon)
		return -1;
	return 0;
}

inline void copy3d(FLT *out, const FLT *in) {
	out[0] = in[0];
	out[1] = in[1];
	out[2] = in[2];
}

FLT magnitude3d(const FLT *a) { return FLT_SQRT(a[0] * a[0] + a[1] * a[1] + a[2] * a[2]); }
FLT dist3d(const FLT *a, const FLT *b) {
	LinmathPoint3d tmp;
	sub3d(tmp, a, b);
	return magnitude3d(tmp);
}

FLT anglebetween3d(FLT *a, FLT *b) {
	FLT an[3];
	FLT bn[3];
	normalize3d(an, a);
	normalize3d(bn, b);
	FLT dot = dot3d(an, bn);
	if (dot < -0.9999999)
		return LINMATHPI;
	if (dot > 0.9999999)
		return 0;
	return FLT_ACOS(dot);
}

// algorithm found here: http://inside.mines.edu/fs_home/gmurray/ArbitraryAxisRotation/
inline void rotatearoundaxis(FLT *outvec3, FLT *invec3, FLT *axis, FLT angle) {
	// TODO: this really should be external.
	normalize3d(axis, axis);

	FLT s = FLT_SIN(angle);
	FLT c = FLT_COS(angle);

	FLT u = axis[0];
	FLT v = axis[1];
	FLT w = axis[2];

	FLT x = invec3[0];
	FLT y = invec3[1];
	FLT z = invec3[2];

	outvec3[0] = u * (u * x + v * y + w * z) * (1 - c) + x * c + (-w * y + v * z) * s;
	outvec3[1] = v * (u * x + v * y + w * z) * (1 - c) + y * c + (w * x - u * z) * s;
	outvec3[2] = w * (u * x + v * y + w * z) * (1 - c) + z * c + (-v * x + u * y) * s;
}

inline void angleaxisfrom2vect(FLT *angle, FLT *axis, FLT *src, FLT *dest) {
	FLT v0[3];
	FLT v1[3];
	normalize3d(v0, src);
	normalize3d(v1, dest);

	FLT d = dot3d(v0, v1); // v0.dotProduct(v1);

	// If dot == 1, vectors are the same
	// If dot == -1, vectors are opposite
	if (FLT_FABS(d - 1) < DEFAULT_EPSILON) {
		axis[0] = 0;
		axis[1] = 1;
		axis[2] = 0;
		*angle = 0;
		return;
	} else if (FLT_FABS(d + 1) < DEFAULT_EPSILON) {
		axis[0] = 0;
		axis[1] = 1;
		axis[2] = 0;
		*angle = LINMATHPI;
		return;
	}

	FLT v0Len = magnitude3d(v0);
	FLT v1Len = magnitude3d(v1);

	*angle = FLT_ACOS(d / (v0Len * v1Len));

	// cross3d(c, v0, v1);
	cross3d(axis, v1, v0);
}

inline void axisanglefromquat(FLT *angle, FLT *axis, FLT *q) {
	// this way might be fine, too.
	// FLT dist = FLT_SQRT((q[1] * q[1]) + (q[2] * q[2]) + (q[3] * q[3]));
	//
	//*angle = 2 * FLT_ATAN2(dist, q[0]);

	// axis[0] = q[1] / dist;
	// axis[1] = q[2] / dist;
	// axis[2] = q[3] / dist;

	// Good mathematical foundation for this algorithm found here:
	// http://www.euclideanspace.com/maths/geometry/rotations/conversions/quaternionToAngle/index.htm

	FLT tmp[4] = {q[0], q[1], q[2], q[3]};

	quatnormalize(tmp, q);

	if (FLT_FABS(q[0] - 1) < FLT_EPSILON) {
		// we have a degenerate case where we're rotating approx. 0 degrees
		*angle = 0;
		axis[0] = 1;
		axis[1] = 0;
		axis[2] = 0;
		return;
	}

	axis[0] = tmp[1] / sqrt(1 - (tmp[0] * tmp[0]));
	axis[1] = tmp[2] / sqrt(1 - (tmp[0] * tmp[0]));
	axis[2] = tmp[3] / sqrt(1 - (tmp[0] * tmp[0]));

	*angle = 2 * FLT_ACOS(tmp[0]);
}

/////////////////////////////////////QUATERNIONS//////////////////////////////////////////
// Originally from Mercury (Copyright (C) 2009 by Joshua Allen, Charles Lohr, Adam Lowman)
// Under the mit/X11 license.

inline void quatset(LinmathQuat q, FLT w, FLT x, FLT y, FLT z) {
	q[0] = w;
	q[1] = x;
	q[2] = y;
	q[3] = z;
}

inline void quatsetnone(LinmathQuat q) {
	q[0] = 1;
	q[1] = 0;
	q[2] = 0;
	q[3] = 0;
}

inline void quatcopy(LinmathQuat qout, const LinmathQuat qin) {
	qout[0] = qin[0];
	qout[1] = qin[1];
	qout[2] = qin[2];
	qout[3] = qin[3];
}

inline void quatfromeuler(LinmathQuat q, const LinmathEulerAngle euler) {
	FLT X = euler[0] / 2.0f; // roll
	FLT Y = euler[1] / 2.0f; // pitch
	FLT Z = euler[2] / 2.0f; // yaw

	FLT cx = FLT_COS(X);
	FLT sx = FLT_SIN(X);
	FLT cy = FLT_COS(Y);
	FLT sy = FLT_SIN(Y);
	FLT cz = FLT_COS(Z);
	FLT sz = FLT_SIN(Z);

	// Correct according to
	// http://en.wikipedia.org/wiki/Conversion_between_MQuaternions_and_Euler_angles
	q[0] = cx * cy * cz + sx * sy * sz; // q1
	q[1] = sx * cy * cz - cx * sy * sz; // q2
	q[2] = cx * sy * cz + sx * cy * sz; // q3
	q[3] = cx * cy * sz - sx * sy * cz; // q4
	quatnormalize(q, q);
}

inline void quattoeuler(LinmathEulerAngle euler, const LinmathQuat q) {
	// According to http://en.wikipedia.org/wiki/Conversion_between_quaternions_and_Euler_angles (Oct 26, 2009)
	euler[0] = FLT_ATAN2(2 * (q[0] * q[1] + q[2] * q[3]), 1 - 2 * (q[1] * q[1] + q[2] * q[2]));
	euler[1] = FLT_ASIN(2 * (q[0] * q[2] - q[3] * q[1]));
	euler[2] = FLT_ATAN2(2 * (q[0] * q[3] + q[1] * q[2]), 1 - 2 * (q[2] * q[2] + q[3] * q[3]));
}

inline void quatfromaxisangle(LinmathQuat q, const FLT *axis, FLT radians) {
	FLT v[3];
	normalize3d(v, axis);

	FLT sn = FLT_SIN(radians / 2.0f);
	q[0] = FLT_COS(radians / 2.0f);
	q[1] = sn * v[0];
	q[2] = sn * v[1];
	q[3] = sn * v[2];

	quatnormalize(q, q);
}

FLT quatmagnitude(const LinmathQuat q) {
	return FLT_SQRT((q[0] * q[0]) + (q[1] * q[1]) + (q[2] * q[2]) + (q[3] * q[3]));
}

FLT quatinvsqmagnitude(const LinmathQuat q) {
	return ((FLT)1.) / FLT_SQRT((q[0] * q[0]) + (q[1] * q[1]) + (q[2] * q[2]) + (q[3] * q[3]));
}

inline void quatnormalize(LinmathQuat qout, const LinmathQuat qin) {
	FLT imag = quatinvsqmagnitude(qin);
	quatscale(qout, qin, imag);
}

inline void quattomatrix(FLT *matrix44, const LinmathQuat qin) {
	FLT q[4];
	quatnormalize(q, qin);

	// Reduced calulation for speed
	FLT xx = 2 * q[1] * q[1];
	FLT xy = 2 * q[1] * q[2];
	FLT xz = 2 * q[1] * q[3];
	FLT xw = 2 * q[1] * q[0];

	FLT yy = 2 * q[2] * q[2];
	FLT yz = 2 * q[2] * q[3];
	FLT yw = 2 * q[2] * q[0];

	FLT zz = 2 * q[3] * q[3];
	FLT zw = 2 * q[3] * q[0];

	// opengl major
	matrix44[0] = 1 - yy - zz;
	matrix44[1] = xy - zw;
	matrix44[2] = xz + yw;
	matrix44[3] = 0;

	matrix44[4] = xy + zw;
	matrix44[5] = 1 - xx - zz;
	matrix44[6] = yz - xw;
	matrix44[7] = 0;

	matrix44[8] = xz - yw;
	matrix44[9] = yz + xw;
	matrix44[10] = 1 - xx - yy;
	matrix44[11] = 0;

	matrix44[12] = 0;
	matrix44[13] = 0;
	matrix44[14] = 0;
	matrix44[15] = 1;
}

inline void quatfrommatrix33(FLT *q, const FLT *m) {
	FLT m00 = m[0], m01 = m[1], m02 = m[2], m10 = m[3], m11 = m[4], m12 = m[5], m20 = m[6], m21 = m[7], m22 = m[8];

	FLT tr = m00 + m11 + m22;

	if (tr > 0) {
		FLT S = sqrt(tr + 1.0) * 2; // S=4*qw
		q[0] = 0.25 * S;
		q[1] = (m21 - m12) / S;
		q[2] = (m02 - m20) / S;
		q[3] = (m10 - m01) / S;
	} else if ((m00 > m11) & (m00 > m22)) {
		FLT S = sqrt(1.0 + m00 - m11 - m22) * 2; // S=4*q[1]
		q[0] = (m21 - m12) / S;
		q[1] = 0.25 * S;
		q[2] = (m01 + m10) / S;
		q[3] = (m02 + m20) / S;
	} else if (m11 > m22) {
		FLT S = sqrt(1.0 + m11 - m00 - m22) * 2; // S=4*q[2]
		q[0] = (m02 - m20) / S;
		q[1] = (m01 + m10) / S;
		q[2] = 0.25 * S;
		q[3] = (m12 + m21) / S;
	} else {
		FLT S = sqrt(1.0 + m22 - m00 - m11) * 2; // S=4*q[3]
		q[0] = (m10 - m01) / S;
		q[1] = (m02 + m20) / S;
		q[2] = (m12 + m21) / S;
		q[3] = 0.25 * S;
	}
}

inline void quatfrommatrix(LinmathQuat q, const FLT *matrix44) {
	// Algorithm from http://www.euclideanspace.com/maths/geometry/rotations/conversions/matrixToQuaternion/
	FLT tr = matrix44[0] + matrix44[5] + matrix44[10];

	if (tr > 0) {
		FLT S = FLT_SQRT(tr + 1.0) * 2.; // S=4*qw
		q[0] = 0.25f * S;
		q[1] = (matrix44[9] - matrix44[6]) / S;
		q[2] = (matrix44[2] - matrix44[8]) / S;
		q[3] = (matrix44[4] - matrix44[1]) / S;
	} else if ((matrix44[0] > matrix44[5]) && (matrix44[0] > matrix44[10])) {
		FLT S = FLT_SQRT(1.0 + matrix44[0] - matrix44[5] - matrix44[10]) * 2.; // S=4*qx
		q[0] = (matrix44[9] - matrix44[6]) / S;
		q[1] = 0.25f * S;
		q[2] = (matrix44[1] + matrix44[4]) / S;
		q[3] = (matrix44[2] + matrix44[8]) / S;
	} else if (matrix44[5] > matrix44[10]) {
		FLT S = FLT_SQRT(1.0 + matrix44[5] - matrix44[0] - matrix44[10]) * 2.; // S=4*qy
		q[0] = (matrix44[2] - matrix44[8]) / S;
		q[1] = (matrix44[1] + matrix44[4]) / S;
		q[2] = 0.25f * S;
		q[3] = (matrix44[6] + matrix44[9]) / S;
	} else {
		FLT S = FLT_SQRT(1.0 + matrix44[10] - matrix44[0] - matrix44[5]) * 2.; // S=4*qz
		q[0] = (matrix44[4] - matrix44[1]) / S;
		q[1] = (matrix44[2] + matrix44[8]) / S;
		q[2] = (matrix44[6] + matrix44[9]) / S;
		q[3] = 0.25 * S;
	}
}

// Algorithm from http://www.euclideanspace.com/maths/geometry/rotations/conversions/quaternionToMatrix/
inline void quattomatrix33(FLT *matrix33, const LinmathQuat qin) {
	FLT q[4];
	quatnormalize(q, qin);

	// Reduced calulation for speed
	FLT xx = 2 * q[1] * q[1];
	FLT xy = 2 * q[1] * q[2];
	FLT xz = 2 * q[1] * q[3];
	FLT xw = 2 * q[1] * q[0];

	FLT yy = 2 * q[2] * q[2];
	FLT yz = 2 * q[2] * q[3];
	FLT yw = 2 * q[2] * q[0];

	FLT zz = 2 * q[3] * q[3];
	FLT zw = 2 * q[3] * q[0];

	// opengl major
	matrix33[0] = 1 - yy - zz;
	matrix33[1] = xy + zw;
	matrix33[2] = xz - yw;

	matrix33[3] = xy - zw;
	matrix33[4] = 1 - xx - zz;
	matrix33[5] = yz + xw;

	matrix33[6] = xz + yw;
	matrix33[7] = yz - xw;
	matrix33[8] = 1 - xx - yy;
}

inline void quatgetconjugate(LinmathQuat qout, const LinmathQuat qin) {
	qout[0] = qin[0];
	qout[1] = -qin[1];
	qout[2] = -qin[2];
	qout[3] = -qin[3];
}

inline void quatgetreciprocal(LinmathQuat qout, const LinmathQuat qin) {
	FLT m = quatinvsqmagnitude(qin);
	quatgetconjugate(qout, qin);
	quatscale(qout, qout, m);
}

inline void quatsub(LinmathQuat qout, const FLT *a, const FLT *b) {
	qout[0] = a[0] - b[0];
	qout[1] = a[1] - b[1];
	qout[2] = a[2] - b[2];
	qout[3] = a[3] - b[3];
}

inline void quatadd(LinmathQuat qout, const FLT *a, const FLT *b) {
	qout[0] = a[0] + b[0];
	qout[1] = a[1] + b[1];
	qout[2] = a[2] + b[2];
	qout[3] = a[3] + b[3];
}

inline void quatrotateabout(LinmathQuat qout, const LinmathQuat q1, const LinmathQuat q2) {
	// NOTE: Does not normalize
	qout[0] = (q1[0] * q2[0]) - (q1[1] * q2[1]) - (q1[2] * q2[2]) - (q1[3] * q2[3]);
	qout[1] = (q1[0] * q2[1]) + (q1[1] * q2[0]) + (q1[2] * q2[3]) - (q1[3] * q2[2]);
	qout[2] = (q1[0] * q2[2]) - (q1[1] * q2[3]) + (q1[2] * q2[0]) + (q1[3] * q2[1]);
	qout[3] = (q1[0] * q2[3]) + (q1[1] * q2[2]) - (q1[2] * q2[1]) + (q1[3] * q2[0]);
}

inline void quatscale(LinmathQuat qout, const LinmathQuat qin, FLT s) {
	qout[0] = qin[0] * s;
	qout[1] = qin[1] * s;
	qout[2] = qin[2] * s;
	qout[3] = qin[3] * s;
}

FLT quatinnerproduct(const LinmathQuat qa, const LinmathQuat qb) {
	return (qa[0] * qb[0]) + (qa[1] * qb[1]) + (qa[2] * qb[2]) + (qa[3] * qb[3]);
}

inline void quatouterproduct(FLT *outvec3, LinmathQuat qa, LinmathQuat qb) {
	outvec3[0] = (qa[0] * qb[1]) - (qa[1] * qb[0]) - (qa[2] * qb[3]) + (qa[3] * qb[2]);
	outvec3[1] = (qa[0] * qb[2]) + (qa[1] * qb[3]) - (qa[2] * qb[0]) - (qa[3] * qb[1]);
	outvec3[2] = (qa[0] * qb[3]) - (qa[1] * qb[2]) + (qa[2] * qb[1]) - (qa[3] * qb[0]);
}

inline void quatevenproduct(LinmathQuat q, LinmathQuat qa, LinmathQuat qb) {
	q[0] = (qa[0] * qb[0]) - (qa[1] * qb[1]) - (qa[2] * qb[2]) - (qa[3] * qb[3]);
	q[1] = (qa[0] * qb[1]) + (qa[1] * qb[0]);
	q[2] = (qa[0] * qb[2]) + (qa[2] * qb[0]);
	q[3] = (qa[0] * qb[3]) + (qa[3] * qb[0]);
}

inline void quatoddproduct(FLT *outvec3, LinmathQuat qa, LinmathQuat qb) {
	outvec3[0] = (qa[2] * qb[3]) - (qa[3] * qb[2]);
	outvec3[1] = (qa[3] * qb[1]) - (qa[1] * qb[3]);
	outvec3[2] = (qa[1] * qb[2]) - (qa[2] * qb[1]);
}

inline void quatslerp(LinmathQuat q, const LinmathQuat qa, const LinmathQuat qb, FLT t) {
	FLT an[4];
	FLT bn[4];
	quatnormalize(an, qa);
	quatnormalize(bn, qb);
	FLT cosTheta = quatinnerproduct(an, bn);
	FLT sinTheta;

	// Careful: If cosTheta is exactly one, or even if it's infinitesimally over, it'll
	// cause SQRT to produce not a number, and screw everything up.
	if (1 - (cosTheta * cosTheta) <= 0)
		sinTheta = 0;
	else
		sinTheta = FLT_SQRT(1 - (cosTheta * cosTheta));

	FLT Theta = FLT_ACOS(cosTheta); // Theta is half the angle between the 2 MQuaternions

	if (FLT_FABS(Theta) < DEFAULT_EPSILON)
		quatcopy(q, qa);
	else if (FLT_FABS(sinTheta) < DEFAULT_EPSILON) {
		quatadd(q, qa, qb);
		quatscale(q, q, 0.5);
	} else {
		FLT aside[4];
		FLT bside[4];
		quatscale(bside, qb, FLT_SIN(t * Theta));
		quatscale(aside, qa, FLT_SIN((1 - t) * Theta));
		quatadd(q, aside, bside);
		quatscale(q, q, ((FLT)1.) / sinTheta);
	}
}

inline void quatrotatevector(FLT *vec3out, const LinmathQuat quat, const FLT *vec3in) {
	// See: http://www.geeks3d.com/20141201/how-to-rotate-a-vertex-by-a-quaternion-in-glsl/

	FLT tmp[3];
	FLT tmp2[3];
	cross3d(tmp, &quat[1], vec3in);
	tmp[0] += vec3in[0] * quat[0];
	tmp[1] += vec3in[1] * quat[0];
	tmp[2] += vec3in[2] * quat[0];
	cross3d(tmp2, &quat[1], tmp);
	vec3out[0] = vec3in[0] + 2 * tmp2[0];
	vec3out[1] = vec3in[1] + 2 * tmp2[1];
	vec3out[2] = vec3in[2] + 2 * tmp2[2];
}

// Matrix Stuff

Matrix3x3 inverseM33(const Matrix3x3 mat) {
	Matrix3x3 newMat;
	for (int a = 0; a < 3; a++) {
		for (int b = 0; b < 3; b++) {
			newMat.val[a][b] = mat.val[a][b];
		}
	}

	for (int i = 0; i < 3; i++) {
		for (int j = i + 1; j < 3; j++) {
			FLT tmp = newMat.val[i][j];
			newMat.val[i][j] = newMat.val[j][i];
			newMat.val[j][i] = tmp;
		}
	}

	return newMat;
}

inline void rotation_between_vecs_to_m3(Matrix3x3 *m, const FLT v1[3], const FLT v2[3]) {
	FLT q[4];

	quatfrom2vectors(q, v1, v2);

	quattomatrix33(&(m->val[0][0]), q);
}

inline void rotate_vec(FLT *out, const FLT *in, Matrix3x3 rot) {
	out[0] = rot.val[0][0] * in[0] + rot.val[1][0] * in[1] + rot.val[2][0] * in[2];
	out[1] = rot.val[0][1] * in[0] + rot.val[1][1] * in[1] + rot.val[2][1] * in[2];
	out[2] = rot.val[0][2] * in[0] + rot.val[1][2] * in[1] + rot.val[2][2] * in[2];

	return;
}

// This function based on code from Object-oriented Graphics Rendering Engine
// Copyright(c) 2000 - 2012 Torus Knot Software Ltd
// under MIT license
// http://www.ogre3d.org/docs/api/1.9/_ogre_vector3_8h_source.html

/** Gets the shortest arc quaternion to rotate this vector to the destination
vector.
@remarks
If you call this with a dest vector that is close to the inverse
of this vector, we will rotate 180 degrees around a generated axis if
since in this case ANY axis of rotation is valid.
*/
inline void quatfrom2vectors(FLT *q, const FLT *src, const FLT *dest) {
	// Based on Stan Melax's article in Game Programming Gems

	// Copy, since cannot modify local
	FLT v0[3];
	FLT v1[3];
	normalize3d(v0, src);
	normalize3d(v1, dest);

	FLT d = dot3d(v0, v1); // v0.dotProduct(v1);
	// If dot == 1, vectors are the same
	if (d >= 1.0f) {
		quatsetnone(q);
		return;
	}
	if (d < (1e-6f - 1.0f)) {
		// Generate an axis
		FLT unitX[3] = {1, 0, 0};
		FLT unitY[3] = {0, 1, 0};

		FLT axis[3];
		cross3d(axis, unitX, src);												  // pick an angle
		if ((axis[0] < 1.0e-35f) && (axis[1] < 1.0e-35f) && (axis[2] < 1.0e-35f)) // pick another if colinear
		{
			cross3d(axis, unitY, src);
		}
		normalize3d(axis, axis);
		quatfromaxisangle(q, axis, LINMATHPI);
	} else {
		FLT s = FLT_SQRT((1 + d) * 2);
		FLT invs = 1 / s;

		FLT c[3];
		cross3d(c, v0, v1);

		q[0] = s * 0.5f;
		q[1] = c[0] * invs;
		q[2] = c[1] * invs;
		q[3] = c[2] * invs;

		quatnormalize(q, q);
	}
}

inline void matrix44copy(FLT *mout, const FLT *minm) { memcpy(mout, minm, sizeof(FLT) * 16); }

inline void matrix44transpose(FLT *mout, const FLT *minm) {
	mout[0] = minm[0];
	mout[1] = minm[4];
	mout[2] = minm[8];
	mout[3] = minm[12];

	mout[4] = minm[1];
	mout[5] = minm[5];
	mout[6] = minm[9];
	mout[7] = minm[13];

	mout[8] = minm[2];
	mout[9] = minm[6];
	mout[10] = minm[10];
	mout[11] = minm[14];

	mout[12] = minm[3];
	mout[13] = minm[7];
	mout[14] = minm[11];
	mout[15] = minm[15];
}

inline void ApplyPoseToPoint(LinmathPoint3d pout, const LinmathPose *pose, const LinmathPoint3d pin) {
	quatrotatevector(pout, pose->Rot, pin);
	add3d(pout, pout, pose->Pos);
}

inline void ApplyPoseToPose(LinmathPose *pout, const LinmathPose *lhs_pose, const LinmathPose *rhs_pose) {
	ApplyPoseToPoint(pout->Pos, lhs_pose, rhs_pose->Pos);
	quatrotateabout(pout->Rot, lhs_pose->Rot, rhs_pose->Rot);
}

inline void InvertPose(LinmathPose *poseout, const LinmathPose *pose) {
	quatgetreciprocal(poseout->Rot, pose->Rot);

	quatrotatevector(poseout->Pos, poseout->Rot, pose->Pos);
	scale3d(poseout->Pos, poseout->Pos, -1);
}

inline void PoseToMatrix(FLT *matrix44, const LinmathPose *pose_in) {
	quattomatrix(matrix44, pose_in->Rot);

	/*
	matrix44[12] = pose_in->Pos[0];
	matrix44[13] = pose_in->Pos[1];
	matrix44[14] = pose_in->Pos[2];
	*/
	matrix44[3] = pose_in->Pos[0];
	matrix44[7] = pose_in->Pos[1];
	matrix44[11] = pose_in->Pos[2];
}

LinmathQuat LinmathQuat_Identity = {1.0};
LinmathPose LinmathPose_Identity = {.Rot = {1.0}};