libcruft-util/matrix.cpp

278 lines
7.2 KiB
C++

/*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*
* Copyright 2011-2015 Danny Robson <danny@nerdcruft.net>
*/
#include "matrix.hpp"
#include "debug/assert.hpp"
#include "iterator/infix.hpp"
#include "point.hpp"
#include <cstring>
#include <cmath>
using cruft::matrix;
///////////////////////////////////////////////////////////////////////////////
template <std::size_t Rows, std::size_t Cols, typename T>
T
cruft::matrix<Rows,Cols,T>::determinant (void) const
{
return cruft::determinant (*this);
}
//-----------------------------------------------------------------------------
template <std::size_t Rows, std::size_t Cols, typename T>
cruft::matrix<Rows,Cols,T>
cruft::matrix<Rows,Cols,T>::inverse (void) const
{
return cruft::inverse (*this);
}
///////////////////////////////////////////////////////////////////////////////
template <std::size_t Rows, std::size_t Cols, typename T>
matrix<Cols,Rows,T>
cruft::transposed (const matrix<Rows,Cols,T> &m)
{
cruft::matrix<Cols,Rows,T> res;
for (std::size_t y = 0; y < Rows; ++y)
for (std::size_t x = 0; x < Cols; ++x)
res[y][x] = m[x][y];
return res;
}
//-----------------------------------------------------------------------------
template cruft::matrix3f cruft::transposed (const matrix3f&);
template cruft::matrix4f cruft::transposed (const matrix4f&);
///////////////////////////////////////////////////////////////////////////////
template <std::size_t Rows, std::size_t Cols, typename T>
bool
matrix<Rows,Cols,T>::is_affine (void) const
{
if (Rows != Cols)
return false;
for (std::size_t i = 0; i < Rows - 1; ++i)
if (!exactly_zero (values[Rows-1][i]))
return false;
return equal (values[Rows-1][Rows-1], T{1});
}
//-----------------------------------------------------------------------------
template <typename T>
cruft::matrix4<T>
cruft::ortho (T l, T r, // left, right
T b, T t, // bottom, top
T n, T f) // near, far
{
CHECK_GT (f, n);
T tx = - (r + l) / (r - l);
T ty = - (t + b) / (t - b);
T tz = - (f + n) / (f - n);
T rl = 2 / (r - l);
T tb = 2 / (t - b);
T fn = -2 / (f - n);
return {{
{ rl, 0, 0, tx },
{ 0, tb, 0, ty },
{ 0, 0, fn, tz },
{ 0, 0, 0, 1 },
}};
}
template cruft::matrix4f cruft::ortho (float, float, float, float, float, float);
//-----------------------------------------------------------------------------
template <typename T>
cruft::matrix4<T>
cruft::ortho2D (T left, T right,
T bottom, T top)
{
return ortho (left, right, bottom, top, T{-1}, T{1});
}
template cruft::matrix4f cruft::ortho2D (float, float, float, float);
//-----------------------------------------------------------------------------
template <typename T>
cruft::matrix4<T>
cruft::perspective (T fov, T aspect, range<T> Z)
{
CHECK_INCLUSIVE (fov, 0, 2 * cruft::pi<T>);
CHECK_GE (Z.lo, 0);
CHECK_GE (Z.hi, 0);
T f = cos (T{0.5} * fov) / sin (T{0.5} * fov);
T x = f / aspect;
T y = f;
T z1 = (Z.hi + Z.lo) / (Z.lo - Z.hi);
T z2 = (2 * Z.hi * Z.lo) / (Z.lo - Z.hi);
return { {
{ x, 0, 0, 0 },
{ 0, y, 0, 0 },
{ 0, 0, z1, z2 },
{ 0, 0, -1, 0 }
} };
}
template cruft::matrix4f cruft::perspective<float> (float, float, range<float>);
//-----------------------------------------------------------------------------
// Emulates gluLookAt
//
// Translates the viewpoint to the origin, then rotates the world to point
// along eye to centre (negative-Z).
// Implemented for right handed world coordinates.
//
// Assumes 'up' is normalised.
template <typename T>
cruft::matrix4<T>
cruft::look_at (const cruft::point<3,T> eye,
const cruft::point<3,T> centre,
const cruft::vector<3,T> up)
{
CHECK (is_normalised (up));
const auto forward = normalised (centre - eye);
const auto side = normalised (cross (forward, up));
const auto newup = cross (side, forward);
const auto &f = forward, &s = side, &u = newup;
const cruft::matrix4<T> rot {{
{ s.x, s.y, s.z, 0 },
{ u.x, u.y, u.z, 0 },
{-f.x,-f.y,-f.z, 0 },
{ 0, 0, 0, 1 },
}};
return rot * cruft::translation (0-eye);
}
template cruft::matrix4f cruft::look_at (cruft::point3f, cruft::point3f, cruft::vector3f);
///////////////////////////////////////////////////////////////////////////////
template <typename T>
cruft::matrix4<T>
cruft::rotation (T angle, cruft::vector<3,T> about)
{
CHECK (is_normalised (about));
T c = std::cos (angle);
T s = std::sin (angle);
T x = about.x,
y = about.y,
z = about.z;
return { {
{ x * x * (1 - c) + c,
x * y * (1 - c) - z * s,
x * z * (1 - c) + y * s,
0
},
{ y * x * (1 - c) + z * s,
y * y * (1 - c) + c,
y * z * (1 - c) - x * s,
0
},
{ z * x * (1 - c) - y * s,
z * y * (1 - c) + x * s,
z * z * (1 - c) + c,
0
},
{ 0, 0, 0, 1 }
} };
}
template cruft::matrix4f cruft::rotation (float, cruft::vector3f);
//-----------------------------------------------------------------------------
template struct cruft::matrix<2,2,float>;
template struct cruft::matrix<2,2,double>;
template struct cruft::matrix<3,3,float>;
template struct cruft::matrix<3,3,double>;
template struct cruft::matrix<4,4,float>;
template struct cruft::matrix<4,4,double>;
///////////////////////////////////////////////////////////////////////////////
// Uses the algorithm from:
// "Extracting Euler Angles from a Rotation Matrix" by
// Mike Day, Insomniac Games.
template <std::size_t Rows, std::size_t Cols, typename T>
cruft::vector<3,T>
cruft::to_euler (const matrix<Rows,Cols,T> &m)
{
static_assert (Rows == Cols && (Rows == 3 || Rows == 4),
"only defined for 3d affine transforms");
const auto theta0 = std::atan2 (m[2][1], m[2][2]);
const auto c1 = std::hypot (m[0][0], m[1][0]);
const auto theta1 = std::atan2 (-m[2][0], c1);
const auto s0 = std::sin(theta0);
const auto c0 = std::cos(theta0);
const auto theta2 = std::atan2(
s0 * m[0][2] - c0 * m[0][1],
c0 * m[1][1] - s0 * m[1][2]
);
return { theta0, theta1, theta2 };
}
//-----------------------------------------------------------------------------
template cruft::vector<3,float> cruft::to_euler (const matrix<3,3,float>&);
template cruft::vector<3,float> cruft::to_euler (const matrix<4,4,float>&);
///////////////////////////////////////////////////////////////////////////////
#include "iterator/infix.hpp"
#include "coord/iostream.hpp"
#include <ostream>
template <std::size_t Rows, std::size_t Cols, typename T>
std::ostream&
cruft::operator<< (std::ostream &os, matrix<Rows,Cols,T> const &m)
{
os << '[';
std::copy (
std::cbegin (m),
std::cend (m),
iterator::infix_iterator<decltype(m[0])> (os, ", ")
);
return os << ']';
}
template std::ostream& cruft::operator<< (std::ostream&, matrix<4,4,f32> const&);