crown-engine/engine/core/math/Mat3.cpp

/*
Copyright (c) 2013 Daniele Bartolini, Michele Rossi
Copyright (c) 2012 Daniele Bartolini, Simone Boscaratto

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 "Assert.h"
#include "Mat3.h"
#include "Types.h"
#include "Mat4.h"
#include "MathUtils.h"
#include "Quat.h"
#include "Vec3.h"

namespace crown
{

const Mat3 Mat3::IDENTITY = Mat3(1.0, 0.0, 0.0, 0.0, 1.0, 0.0, 0.0, 0.0, 1.0);

//-----------------------------------------------------------------------------
Mat3::Mat3()
{
}

//-----------------------------------------------------------------------------
Mat3::Mat3(float r1c1, float r2c1, float r3c1, float r1c2, float r2c2, float r3c2,
	float r1c3, float r2c3, float r3c3)
{
	m[0] = r1c1;
	m[1] = r2c1;
	m[2] = r3c1;
	m[3] = r1c2;
	m[4] = r2c2;
	m[5] = r3c2;
	m[6] = r1c3;
	m[7] = r2c3;
	m[8] = r3c3;
}

//-----------------------------------------------------------------------------
Mat3::Mat3(const float v[9])
{
	m[0] = v[0];
	m[1] = v[1];
	m[2] = v[2];
	m[3] = v[3];
	m[4] = v[4];
	m[5] = v[5];
	m[6] = v[6];
	m[7] = v[7];
	m[8] = v[8];
}

//-----------------------------------------------------------------------------
Mat3::Mat3(const Mat3& a)
{
	m[0] = a.m[0];
	m[1] = a.m[1];
	m[2] = a.m[2];
	m[3] = a.m[3];
	m[4] = a.m[4];
	m[5] = a.m[5];
	m[6] = a.m[6];
	m[7] = a.m[7];
	m[8] = a.m[8];
}

//-----------------------------------------------------------------------------
Mat3& Mat3::operator=(const Mat3& a)
{
	m[0] = a.m[0];
	m[1] = a.m[1];
	m[2] = a.m[2];
	m[3] = a.m[3];
	m[4] = a.m[4];
	m[5] = a.m[5];
	m[6] = a.m[6];
	m[7] = a.m[7];
	m[8] = a.m[8];

	return *this;
}

//-----------------------------------------------------------------------------
float Mat3::operator[](uint32_t i) const
{
	CE_ASSERT(i < 9, "Index must be < 9");

	return m[i];
}

//-----------------------------------------------------------------------------
float& Mat3::operator[](uint32_t i)
{
	CE_ASSERT(i < 9, "Index must be < 9");

	return m[i];
}

//-----------------------------------------------------------------------------
float Mat3::operator()(uint32_t row, uint32_t column) const
{
	CE_ASSERT(row < 3 && column < 3, "Row and column must be < 3");

	return m[row + column * 3];
}

//-----------------------------------------------------------------------------
Mat3 Mat3::operator+(const Mat3& a) const
{
	Mat3 tmp;

	tmp.m[0] = m[0] + a.m[0];
	tmp.m[1] = m[1] + a.m[1];
	tmp.m[2] = m[2] + a.m[2];
	tmp.m[3] = m[3] + a.m[3];
	tmp.m[4] = m[4] + a.m[4];
	tmp.m[5] = m[5] + a.m[5];
	tmp.m[6] = m[6] + a.m[6];
	tmp.m[7] = m[7] + a.m[7];
	tmp.m[8] = m[8] + a.m[8];

	return tmp;
}

//-----------------------------------------------------------------------------
Mat3& Mat3::operator+=(const Mat3& a)
{
	m[0] = m[0] + a.m[0];
	m[1] = m[1] + a.m[1];
	m[2] = m[2] + a.m[2];
	m[3] = m[3] + a.m[3];
	m[4] = m[4] + a.m[4];
	m[5] = m[5] + a.m[5];
	m[6] = m[6] + a.m[6];
	m[7] = m[7] + a.m[7];
	m[8] = m[8] + a.m[8];

	return *this;
}

//-----------------------------------------------------------------------------
Mat3 Mat3::operator-(const Mat3& a) const
{
	Mat3 tmp;

	tmp.m[0] = m[0] - a.m[0];
	tmp.m[1] = m[1] - a.m[1];
	tmp.m[2] = m[2] - a.m[2];
	tmp.m[3] = m[3] - a.m[3];
	tmp.m[4] = m[4] - a.m[4];
	tmp.m[5] = m[5] - a.m[5];
	tmp.m[6] = m[6] - a.m[6];
	tmp.m[7] = m[7] - a.m[7];
	tmp.m[8] = m[8] - a.m[8];

	return tmp;
}

//-----------------------------------------------------------------------------
Mat3& Mat3::operator-=(const Mat3& a)
{
	m[0] = m[0] - a.m[0];
	m[1] = m[1] - a.m[1];
	m[2] = m[2] - a.m[2];
	m[3] = m[3] - a.m[3];
	m[4] = m[4] - a.m[4];
	m[5] = m[5] - a.m[5];
	m[6] = m[6] - a.m[6];
	m[7] = m[7] - a.m[7];
	m[8] = m[8] - a.m[8];

	return *this;
}

//-----------------------------------------------------------------------------
Mat3 Mat3::operator*(float k) const
{
	Mat3 tmp;

	tmp.m[0] = m[0] * k;
	tmp.m[1] = m[1] * k;
	tmp.m[2] = m[2] * k;
	tmp.m[3] = m[3] * k;
	tmp.m[4] = m[4] * k;
	tmp.m[5] = m[5] * k;
	tmp.m[6] = m[6] * k;
	tmp.m[7] = m[7] * k;
	tmp.m[8] = m[8] * k;

	return tmp;
}

//-----------------------------------------------------------------------------
Mat3& Mat3::operator*=(float k)
{
	m[0] *= k;
	m[1] *= k;
	m[2] *= k;
	m[3] *= k;
	m[4] *= k;
	m[5] *= k;
	m[6] *= k;
	m[7] *= k;
	m[8] *= k;

	return *this;
}

//-----------------------------------------------------------------------------
Mat3 Mat3::operator/(float k) const
{
	Mat3 tmp;

	k = (float)1.0 / k;

	tmp.m[0] = m[0] * k;
	tmp.m[1] = m[1] * k;
	tmp.m[2] = m[2] * k;
	tmp.m[3] = m[3] * k;
	tmp.m[4] = m[4] * k;
	tmp.m[5] = m[5] * k;
	tmp.m[6] = m[6] * k;
	tmp.m[7] = m[7] * k;
	tmp.m[8] = m[8] * k;

	return tmp;
}

//-----------------------------------------------------------------------------
Mat3& Mat3::operator/=(float k)
{
	k = (float)1.0 / k;

	m[0] *= k;
	m[1] *= k;
	m[2] *= k;
	m[3] *= k;
	m[4] *= k;
	m[5] *= k;
	m[6] *= k;
	m[7] *= k;
	m[8] *= k;

	return *this;
}

//-----------------------------------------------------------------------------
Vec3 Mat3::operator*(const Vec3& v) const
{
	Vec3 tmp;

	tmp.x = m[0] * v.x + m[3] * v.y + m[6] * v.z;
	tmp.y = m[1] * v.x + m[4] * v.y + m[7] * v.z;
	tmp.z = m[2] * v.x + m[5] * v.y + m[8] * v.z;

	return tmp;
}

//-----------------------------------------------------------------------------
Mat3 Mat3::operator*(const Mat3& a) const
{
	Mat3 tmp;

	tmp.m[0] = m[0] * a.m[0] + m[3] * a.m[1] + m[6] * a.m[2];
	tmp.m[1] = m[1] * a.m[0] + m[4] * a.m[1] + m[7] * a.m[2];
	tmp.m[2] = m[2] * a.m[0] + m[5] * a.m[1] + m[8] * a.m[2];

	tmp.m[3] = m[0] * a.m[3] + m[3] * a.m[4] + m[6] * a.m[5];
	tmp.m[4] = m[1] * a.m[3] + m[4] * a.m[4] + m[7] * a.m[5];
	tmp.m[5] = m[2] * a.m[3] + m[5] * a.m[4] + m[8] * a.m[5];

	tmp.m[6] = m[0] * a.m[6] + m[3] * a.m[7] + m[6] * a.m[8];
	tmp.m[7] = m[1] * a.m[6] + m[4] * a.m[7] + m[7] * a.m[8];
	tmp.m[8] = m[2] * a.m[6] + m[5] * a.m[7] + m[8] * a.m[8];

	return tmp;
}

//-----------------------------------------------------------------------------
Mat3& Mat3::operator*=(const Mat3& a)
{
	Mat3 tmp;

	tmp.m[0] = m[0] * a.m[0] + m[3] * a.m[1] + m[6] * a.m[2];
	tmp.m[1] = m[1] * a.m[0] + m[4] * a.m[1] + m[7] * a.m[2];
	tmp.m[2] = m[2] * a.m[0] + m[5] * a.m[1] + m[8] * a.m[2];

	tmp.m[3] = m[0] * a.m[3] + m[3] * a.m[4] + m[6] * a.m[5];
	tmp.m[4] = m[1] * a.m[3] + m[4] * a.m[4] + m[7] * a.m[5];
	tmp.m[5] = m[2] * a.m[3] + m[5] * a.m[4] + m[8] * a.m[5];

	tmp.m[6] = m[0] * a.m[6] + m[3] * a.m[7] + m[6] * a.m[8];
	tmp.m[7] = m[1] * a.m[6] + m[4] * a.m[7] + m[7] * a.m[8];
	tmp.m[8] = m[2] * a.m[6] + m[5] * a.m[7] + m[8] * a.m[8];

	*this = tmp;

	return *this;
}

//-----------------------------------------------------------------------------
Mat3 operator*(float k, const Mat3& a)
{
	return a * k;
}

//-----------------------------------------------------------------------------
void Mat3::build_rotation_x(float radians)
{
	m[0] = 1.0;
	m[1] = 0.0;
	m[2] = 0.0;
	m[3] = 0.0;
	m[4] = math::cos(radians);
	m[5] = math::sin(radians);
	m[6] = 0.0;
	m[7] = -math::sin(radians);
	m[8] = math::cos(radians);
}

//-----------------------------------------------------------------------------
void Mat3::build_rotation_y(float radians)
{
	m[0] = math::cos(radians);
	m[1] = 0.0;
	m[2] = -math::sin(radians);
	m[3] = 0.0;
	m[4] = 1.0;
	m[5] = 0.0;
	m[6] = math::sin(radians);
	m[7] = 0.0;
	m[8] = math::cos(radians);
}

//-----------------------------------------------------------------------------
void Mat3::build_rotation_z(float radians)
{
	m[0] = math::cos(radians);
	m[1] = math::sin(radians);
	m[2] = 0.0;
	m[3] = -math::sin(radians);
	m[4] = math::cos(radians);
	m[5] = 0.0;
	m[6] = 0.0;
	m[7] = 0.0;
	m[8] = 1.0;
}

//-----------------------------------------------------------------------------
void Mat3::build_rotation(const Vec3& n, float radians)
{
	float a = (float)1.0 - math::cos(radians);
	float sin_a = math::sin(radians);
	float cos_a = math::cos(radians);

	m[0] = n.x * n.x * a + cos_a;
	m[1] = n.x * n.y * a + n.z * sin_a;
	m[2] = n.x * n.z * a - n.y * sin_a;
	m[3] = n.x * n.y * a - n.z * sin_a;
	m[4] = n.y * n.y * a + cos_a;
	m[5] = n.y * n.z * a + n.x * sin_a;
	m[6] = n.x * n.z * a + n.y * sin_a;
	m[7] = n.y * n.z * a - n.x * sin_a;
	m[8] = n.z * n.z * a + cos_a;
}

//-----------------------------------------------------------------------------
Mat3& Mat3::transpose()
{
	float tmp;

	tmp = m[1];
	m[1] = m[3];
	m[3] = tmp;

	tmp = m[2];
	m[2] = m[6];
	m[6] = tmp;

	tmp = m[5];
	m[5] = m[7];
	m[7] = tmp;

	return *this;
}

//-----------------------------------------------------------------------------
Mat3 Mat3::get_transposed() const
{
	Mat3 tmp;

	tmp.m[0] = m[0];
	tmp.m[1] = m[3];
	tmp.m[2] = m[6];
	tmp.m[3] = m[1];
	tmp.m[4] = m[4];
	tmp.m[5] = m[7];
	tmp.m[6] = m[2];
	tmp.m[7] = m[5];
	tmp.m[8] = m[8];

	return tmp;
}

//-----------------------------------------------------------------------------
float Mat3::get_determinant() const
{
	float det;

	det =	m[0] * (m[4] * m[8] - m[7] * m[5]) -
			m[3] * (m[1] * m[8] - m[7] * m[2]) +
			m[6] * (m[1] * m[5] - m[4] * m[2]);

	return det;
}

//-----------------------------------------------------------------------------
Mat3& Mat3::invert()
{
	Mat3 mat;
	float det;

	mat.m[0] = (m[4] * m[8] - m[7] * m[5]);
	mat.m[1] = (m[1] * m[8] - m[7] * m[2]);
	mat.m[2] = (m[1] * m[5] - m[4] * m[2]);

	det = m[0] * mat.m[0] - m[3] * mat.m[1] + m[6] * mat.m[2];
	det = (float)1.0 / det;

	mat.m[3] = (m[3] * m[8] - m[6] * m[5]);
	mat.m[4] = (m[0] * m[8] - m[6] * m[2]);
	mat.m[5] = (m[0] * m[5] - m[3] * m[2]);
	mat.m[6] = (m[3] * m[7] - m[6] * m[4]);
	mat.m[7] = (m[0] * m[7] - m[6] * m[1]);
	mat.m[8] = (m[0] * m[4] - m[3] * m[1]);

	m[0] = + mat.m[0] * det;
	m[1] = - mat.m[1] * det;
	m[2] = + mat.m[2] * det;
	m[3] = - mat.m[3] * det;
	m[4] = + mat.m[4] * det;
	m[5] = - mat.m[5] * det;
	m[6] = + mat.m[6] * det;
	m[7] = - mat.m[7] * det;
	m[8] = + mat.m[8] * det;

	return *this;
}

//-----------------------------------------------------------------------------
inline Mat3 Mat3::get_inverted() const
{
	Mat3 tmp(*this);

	return tmp.invert();
}

//-----------------------------------------------------------------------------
void Mat3::load_identity()
{
	m[0] = m[4] = m[8] = 1.0;
	m[1] = m[2] = m[3] = m[5] = m[6] = m[7] = 0.0;
}

//-----------------------------------------------------------------------------
Vec3 Mat3::get_scale() const
{
	Vec3 tmp;

	tmp.x = m[0];
	tmp.y = m[4];
	tmp.z = m[8];

	return tmp;
}

//-----------------------------------------------------------------------------
void Mat3::set_scale(const Vec3& scale)
{
	m[0] = scale.x;
	m[4] = scale.y;
	m[8] = scale.z;
}

//-----------------------------------------------------------------------------
float* Mat3::to_float_ptr()
{
	return &m[0];
}

//-----------------------------------------------------------------------------
const float* Mat3::to_float_ptr() const
{
	return &m[0];
}

//-----------------------------------------------------------------------------
Mat4 Mat3::to_mat4() const
{
	Mat4 tmp;

	tmp.m[0] = m[0];
	tmp.m[1] = m[1];
	tmp.m[2] = m[2];
	tmp.m[3] = 0.0;
	tmp.m[4] = m[3];
	tmp.m[5] = m[4];
	tmp.m[6] = m[5];
	tmp.m[7] = 0.0;
	tmp.m[8] = m[6];
	tmp.m[9] = m[7];
	tmp.m[10] = m[8];
	tmp.m[11] = 0.0;
	tmp.m[12] = 0.0;
	tmp.m[13] = 0.0;
	tmp.m[14] = 0.0;
	tmp.m[15] = 1.0;

	return tmp;
}

//-----------------------------------------------------------------------------
Quat Mat3::to_quat() const
{
	Quat tmp;

	float fourWSquaredMinusOne = m[0] + m[4] + m[8];
	float fourXSquaredMinusOne = m[0] - m[4] - m[8];
	float fourYSquaredMinusOne = -m[0] + m[4] - m[8];
	float fourZSquaredMinusOne = -m[0] - m[4] + m[8];
	float fourMaxSquaredMinusOne = fourWSquaredMinusOne;
	uint32_t index = 0;

	if (fourXSquaredMinusOne > fourMaxSquaredMinusOne)
	{
		fourMaxSquaredMinusOne = fourXSquaredMinusOne;
		index = 1;
	}

	if (fourYSquaredMinusOne > fourMaxSquaredMinusOne)
	{
		fourMaxSquaredMinusOne = fourYSquaredMinusOne;
		index = 2;
	}

	if (fourZSquaredMinusOne > fourMaxSquaredMinusOne)
	{
		fourMaxSquaredMinusOne = fourZSquaredMinusOne;
		index = 3;
	}

	float biggest = math::sqrt(fourMaxSquaredMinusOne + (float)1.0) * (float)0.5;
	float mult = (float)0.25 / biggest;

	switch (index)
	{
		case 0:
			tmp.w = biggest;
			tmp.v.x = (-m[7] + m[5]) * mult;
			tmp.v.y = (-m[2] + m[6]) * mult;
			tmp.v.z = (-m[3] + m[1]) * mult;
			break;
		case 1:
			tmp.v.x = biggest;
			tmp.w = (-m[7] + m[5]) * mult;
			tmp.v.y = (-m[3] - m[1]) * mult;
			tmp.v.z = (-m[2] - m[6]) * mult;
			break;
		case 2:
			tmp.v.y = biggest;
			tmp.w = (-m[2] + m[6]) * mult;
			tmp.v.x = (-m[3] - m[1]) * mult;
			tmp.v.z = (-m[7] - m[5]) * mult;
			break;
		case 3:
			tmp.v.z = biggest;
			tmp.w = (-m[3] + m[1]) * mult;
			tmp.v.x = (-m[2] - m[6]) * mult;
			tmp.v.y = (-m[7] - m[5]) * mult;
			break;
	}

	return tmp;
}

} // namespace crown