godot/core/math/matrix3.cpp
2017-04-08 00:45:24 +02:00

450 lines
13 KiB
C++

/*************************************************************************/
/* matrix3.cpp */
/*************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* http://www.godotengine.org */
/*************************************************************************/
/* Copyright (c) 2007-2017 Juan Linietsky, Ariel Manzur. */
/* Copyright (c) 2014-2017 Godot Engine contributors (cf. AUTHORS.md) */
/* */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the */
/* "Software"), to deal in the Software without restriction, including */
/* without limitation the rights to use, copy, modify, merge, publish, */
/* distribute, sublicense, and/or sell copies of the Software, and to */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions: */
/* */
/* The above copyright notice and this permission notice shall be */
/* included in all copies or substantial portions of the Software. */
/* */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
/*************************************************************************/
#include "matrix3.h"
#include "math_funcs.h"
#include "os/copymem.h"
#define cofac(row1, col1, row2, col2) \
(elements[row1][col1] * elements[row2][col2] - elements[row1][col2] * elements[row2][col1])
void Matrix3::from_z(const Vector3 &p_z) {
if (Math::abs(p_z.z) > Math_SQRT12) {
// choose p in y-z plane
real_t a = p_z[1] * p_z[1] + p_z[2] * p_z[2];
real_t k = 1.0 / Math::sqrt(a);
elements[0] = Vector3(0, -p_z[2] * k, p_z[1] * k);
elements[1] = Vector3(a * k, -p_z[0] * elements[0][2], p_z[0] * elements[0][1]);
} else {
// choose p in x-y plane
real_t a = p_z.x * p_z.x + p_z.y * p_z.y;
real_t k = 1.0 / Math::sqrt(a);
elements[0] = Vector3(-p_z.y * k, p_z.x * k, 0);
elements[1] = Vector3(-p_z.z * elements[0].y, p_z.z * elements[0].x, a * k);
}
elements[2] = p_z;
}
void Matrix3::invert() {
real_t co[3] = {
cofac(1, 1, 2, 2), cofac(1, 2, 2, 0), cofac(1, 0, 2, 1)
};
real_t det = elements[0][0] * co[0] +
elements[0][1] * co[1] +
elements[0][2] * co[2];
ERR_FAIL_COND(det == 0);
real_t s = 1.0 / det;
set(co[0] * s, cofac(0, 2, 2, 1) * s, cofac(0, 1, 1, 2) * s,
co[1] * s, cofac(0, 0, 2, 2) * s, cofac(0, 2, 1, 0) * s,
co[2] * s, cofac(0, 1, 2, 0) * s, cofac(0, 0, 1, 1) * s);
}
void Matrix3::orthonormalize() {
// Gram-Schmidt Process
Vector3 x = get_axis(0);
Vector3 y = get_axis(1);
Vector3 z = get_axis(2);
x.normalize();
y = (y - x * (x.dot(y)));
y.normalize();
z = (z - x * (x.dot(z)) - y * (y.dot(z)));
z.normalize();
set_axis(0, x);
set_axis(1, y);
set_axis(2, z);
}
Matrix3 Matrix3::orthonormalized() const {
Matrix3 c = *this;
c.orthonormalize();
return c;
}
Matrix3 Matrix3::inverse() const {
Matrix3 inv = *this;
inv.invert();
return inv;
}
void Matrix3::transpose() {
SWAP(elements[0][1], elements[1][0]);
SWAP(elements[0][2], elements[2][0]);
SWAP(elements[1][2], elements[2][1]);
}
Matrix3 Matrix3::transposed() const {
Matrix3 tr = *this;
tr.transpose();
return tr;
}
void Matrix3::scale(const Vector3 &p_scale) {
elements[0][0] *= p_scale.x;
elements[1][0] *= p_scale.x;
elements[2][0] *= p_scale.x;
elements[0][1] *= p_scale.y;
elements[1][1] *= p_scale.y;
elements[2][1] *= p_scale.y;
elements[0][2] *= p_scale.z;
elements[1][2] *= p_scale.z;
elements[2][2] *= p_scale.z;
}
Matrix3 Matrix3::scaled(const Vector3 &p_scale) const {
Matrix3 m = *this;
m.scale(p_scale);
return m;
}
Vector3 Matrix3::get_scale() const {
return Vector3(
Vector3(elements[0][0], elements[1][0], elements[2][0]).length(),
Vector3(elements[0][1], elements[1][1], elements[2][1]).length(),
Vector3(elements[0][2], elements[1][2], elements[2][2]).length());
}
void Matrix3::rotate(const Vector3 &p_axis, real_t p_phi) {
*this = *this * Matrix3(p_axis, p_phi);
}
Matrix3 Matrix3::rotated(const Vector3 &p_axis, real_t p_phi) const {
return *this * Matrix3(p_axis, p_phi);
}
Vector3 Matrix3::get_euler() const {
// rot = cy*cz -cy*sz sy
// cz*sx*sy+cx*sz cx*cz-sx*sy*sz -cy*sx
// -cx*cz*sy+sx*sz cz*sx+cx*sy*sz cx*cy
Matrix3 m = *this;
m.orthonormalize();
Vector3 euler;
euler.y = Math::asin(m[0][2]);
if (euler.y < Math_PI * 0.5) {
if (euler.y > -Math_PI * 0.5) {
euler.x = Math::atan2(-m[1][2], m[2][2]);
euler.z = Math::atan2(-m[0][1], m[0][0]);
} else {
real_t r = Math::atan2(m[1][0], m[1][1]);
euler.z = 0.0;
euler.x = euler.z - r;
}
} else {
real_t r = Math::atan2(m[0][1], m[1][1]);
euler.z = 0;
euler.x = r - euler.z;
}
return euler;
}
void Matrix3::set_euler(const Vector3 &p_euler) {
real_t c, s;
c = Math::cos(p_euler.x);
s = Math::sin(p_euler.x);
Matrix3 xmat(1.0, 0.0, 0.0, 0.0, c, -s, 0.0, s, c);
c = Math::cos(p_euler.y);
s = Math::sin(p_euler.y);
Matrix3 ymat(c, 0.0, s, 0.0, 1.0, 0.0, -s, 0.0, c);
c = Math::cos(p_euler.z);
s = Math::sin(p_euler.z);
Matrix3 zmat(c, -s, 0.0, s, c, 0.0, 0.0, 0.0, 1.0);
//optimizer will optimize away all this anyway
*this = xmat * (ymat * zmat);
}
bool Matrix3::operator==(const Matrix3 &p_matrix) const {
for (int i = 0; i < 3; i++) {
for (int j = 0; j < 3; j++) {
if (elements[i][j] != p_matrix.elements[i][j])
return false;
}
}
return true;
}
bool Matrix3::operator!=(const Matrix3 &p_matrix) const {
return (!(*this == p_matrix));
}
Matrix3::operator String() const {
String mtx;
for (int i = 0; i < 3; i++) {
for (int j = 0; j < 3; j++) {
if (i != 0 || j != 0)
mtx += ", ";
mtx += rtos(elements[i][j]);
}
}
return mtx;
}
Matrix3::operator Quat() const {
Matrix3 m = *this;
m.orthonormalize();
real_t trace = m.elements[0][0] + m.elements[1][1] + m.elements[2][2];
real_t temp[4];
if (trace > 0.0) {
real_t s = Math::sqrt(trace + 1.0);
temp[3] = (s * 0.5);
s = 0.5 / s;
temp[0] = ((m.elements[2][1] - m.elements[1][2]) * s);
temp[1] = ((m.elements[0][2] - m.elements[2][0]) * s);
temp[2] = ((m.elements[1][0] - m.elements[0][1]) * s);
} else {
int i = m.elements[0][0] < m.elements[1][1] ?
(m.elements[1][1] < m.elements[2][2] ? 2 : 1) :
(m.elements[0][0] < m.elements[2][2] ? 2 : 0);
int j = (i + 1) % 3;
int k = (i + 2) % 3;
real_t s = Math::sqrt(m.elements[i][i] - m.elements[j][j] - m.elements[k][k] + 1.0);
temp[i] = s * 0.5;
s = 0.5 / s;
temp[3] = (m.elements[k][j] - m.elements[j][k]) * s;
temp[j] = (m.elements[j][i] + m.elements[i][j]) * s;
temp[k] = (m.elements[k][i] + m.elements[i][k]) * s;
}
return Quat(temp[0], temp[1], temp[2], temp[3]);
}
static const Matrix3 _ortho_bases[24] = {
Matrix3(1, 0, 0, 0, 1, 0, 0, 0, 1),
Matrix3(0, -1, 0, 1, 0, 0, 0, 0, 1),
Matrix3(-1, 0, 0, 0, -1, 0, 0, 0, 1),
Matrix3(0, 1, 0, -1, 0, 0, 0, 0, 1),
Matrix3(1, 0, 0, 0, 0, -1, 0, 1, 0),
Matrix3(0, 0, 1, 1, 0, 0, 0, 1, 0),
Matrix3(-1, 0, 0, 0, 0, 1, 0, 1, 0),
Matrix3(0, 0, -1, -1, 0, 0, 0, 1, 0),
Matrix3(1, 0, 0, 0, -1, 0, 0, 0, -1),
Matrix3(0, 1, 0, 1, 0, 0, 0, 0, -1),
Matrix3(-1, 0, 0, 0, 1, 0, 0, 0, -1),
Matrix3(0, -1, 0, -1, 0, 0, 0, 0, -1),
Matrix3(1, 0, 0, 0, 0, 1, 0, -1, 0),
Matrix3(0, 0, -1, 1, 0, 0, 0, -1, 0),
Matrix3(-1, 0, 0, 0, 0, -1, 0, -1, 0),
Matrix3(0, 0, 1, -1, 0, 0, 0, -1, 0),
Matrix3(0, 0, 1, 0, 1, 0, -1, 0, 0),
Matrix3(0, -1, 0, 0, 0, 1, -1, 0, 0),
Matrix3(0, 0, -1, 0, -1, 0, -1, 0, 0),
Matrix3(0, 1, 0, 0, 0, -1, -1, 0, 0),
Matrix3(0, 0, 1, 0, -1, 0, 1, 0, 0),
Matrix3(0, 1, 0, 0, 0, 1, 1, 0, 0),
Matrix3(0, 0, -1, 0, 1, 0, 1, 0, 0),
Matrix3(0, -1, 0, 0, 0, -1, 1, 0, 0)
};
int Matrix3::get_orthogonal_index() const {
//could be sped up if i come up with a way
Matrix3 orth = *this;
for (int i = 0; i < 3; i++) {
for (int j = 0; j < 3; j++) {
float v = orth[i][j];
if (v > 0.5)
v = 1.0;
else if (v < -0.5)
v = -1.0;
else
v = 0;
orth[i][j] = v;
}
}
for (int i = 0; i < 24; i++) {
if (_ortho_bases[i] == orth)
return i;
}
return 0;
}
void Matrix3::set_orthogonal_index(int p_index) {
//there only exist 24 orthogonal bases in r3
ERR_FAIL_INDEX(p_index, 24);
*this = _ortho_bases[p_index];
}
void Matrix3::get_axis_and_angle(Vector3 &r_axis, real_t &r_angle) const {
double angle, x, y, z; // variables for result
double epsilon = 0.01; // margin to allow for rounding errors
double epsilon2 = 0.1; // margin to distinguish between 0 and 180 degrees
if ((Math::abs(elements[1][0] - elements[0][1]) < epsilon) && (Math::abs(elements[2][0] - elements[0][2]) < epsilon) && (Math::abs(elements[2][1] - elements[1][2]) < epsilon)) {
// singularity found
// first check for identity matrix which must have +1 for all terms
// in leading diagonaland zero in other terms
if ((Math::abs(elements[1][0] + elements[0][1]) < epsilon2) && (Math::abs(elements[2][0] + elements[0][2]) < epsilon2) && (Math::abs(elements[2][1] + elements[1][2]) < epsilon2) && (Math::abs(elements[0][0] + elements[1][1] + elements[2][2] - 3) < epsilon2)) {
// this singularity is identity matrix so angle = 0
r_axis = Vector3(0, 1, 0);
r_angle = 0;
return;
}
// otherwise this singularity is angle = 180
angle = Math_PI;
double xx = (elements[0][0] + 1) / 2;
double yy = (elements[1][1] + 1) / 2;
double zz = (elements[2][2] + 1) / 2;
double xy = (elements[1][0] + elements[0][1]) / 4;
double xz = (elements[2][0] + elements[0][2]) / 4;
double yz = (elements[2][1] + elements[1][2]) / 4;
if ((xx > yy) && (xx > zz)) { // elements[0][0] is the largest diagonal term
if (xx < epsilon) {
x = 0;
y = 0.7071;
z = 0.7071;
} else {
x = Math::sqrt(xx);
y = xy / x;
z = xz / x;
}
} else if (yy > zz) { // elements[1][1] is the largest diagonal term
if (yy < epsilon) {
x = 0.7071;
y = 0;
z = 0.7071;
} else {
y = Math::sqrt(yy);
x = xy / y;
z = yz / y;
}
} else { // elements[2][2] is the largest diagonal term so base result on this
if (zz < epsilon) {
x = 0.7071;
y = 0.7071;
z = 0;
} else {
z = Math::sqrt(zz);
x = xz / z;
y = yz / z;
}
}
r_axis = Vector3(x, y, z);
r_angle = angle;
return;
}
// as we have reached here there are no singularities so we can handle normally
double s = Math::sqrt((elements[1][2] - elements[2][1]) * (elements[1][2] - elements[2][1]) + (elements[2][0] - elements[0][2]) * (elements[2][0] - elements[0][2]) + (elements[0][1] - elements[1][0]) * (elements[0][1] - elements[1][0])); // used to normalise
if (Math::abs(s) < 0.001) s = 1;
// prevent divide by zero, should not happen if matrix is orthogonal and should be
// caught by singularity test above, but I've left it in just in case
angle = Math::acos((elements[0][0] + elements[1][1] + elements[2][2] - 1) / 2);
x = (elements[1][2] - elements[2][1]) / s;
y = (elements[2][0] - elements[0][2]) / s;
z = (elements[0][1] - elements[1][0]) / s;
r_axis = Vector3(x, y, z);
r_angle = angle;
}
Matrix3::Matrix3(const Vector3 &p_euler) {
set_euler(p_euler);
}
Matrix3::Matrix3(const Quat &p_quat) {
real_t d = p_quat.length_squared();
real_t s = 2.0 / d;
real_t xs = p_quat.x * s, ys = p_quat.y * s, zs = p_quat.z * s;
real_t wx = p_quat.w * xs, wy = p_quat.w * ys, wz = p_quat.w * zs;
real_t xx = p_quat.x * xs, xy = p_quat.x * ys, xz = p_quat.x * zs;
real_t yy = p_quat.y * ys, yz = p_quat.y * zs, zz = p_quat.z * zs;
set(1.0 - (yy + zz), xy - wz, xz + wy,
xy + wz, 1.0 - (xx + zz), yz - wx,
xz - wy, yz + wx, 1.0 - (xx + yy));
}
Matrix3::Matrix3(const Vector3 &p_axis, real_t p_phi) {
Vector3 axis_sq(p_axis.x * p_axis.x, p_axis.y * p_axis.y, p_axis.z * p_axis.z);
real_t cosine = Math::cos(p_phi);
real_t sine = Math::sin(p_phi);
elements[0][0] = axis_sq.x + cosine * (1.0 - axis_sq.x);
elements[0][1] = p_axis.x * p_axis.y * (1.0 - cosine) + p_axis.z * sine;
elements[0][2] = p_axis.z * p_axis.x * (1.0 - cosine) - p_axis.y * sine;
elements[1][0] = p_axis.x * p_axis.y * (1.0 - cosine) - p_axis.z * sine;
elements[1][1] = axis_sq.y + cosine * (1.0 - axis_sq.y);
elements[1][2] = p_axis.y * p_axis.z * (1.0 - cosine) + p_axis.x * sine;
elements[2][0] = p_axis.z * p_axis.x * (1.0 - cosine) + p_axis.y * sine;
elements[2][1] = p_axis.y * p_axis.z * (1.0 - cosine) - p_axis.x * sine;
elements[2][2] = axis_sq.z + cosine * (1.0 - axis_sq.z);
}