// David Eberly, Geometric Tools, Redmond WA 98052
// Copyright (c) 1998-2020
// Distributed under the Boost Software License, Version 1.0.
// https://www.boost.org/LICENSE_1_0.txt
// https://www.geometrictools.com/License/Boost/LICENSE_1_0.txt
// Version: 4.0.2019.08.13
#pragma once
#include <Mathematics/Matrix.h>
#include <Mathematics/Vector4.h>
namespace WwiseGTE
{
// Template alias for convenience.
template <typename Real>
using Matrix4x4 = Matrix<4, 4, Real>;
// Geometric operations.
template <typename Real>
Matrix4x4<Real> Inverse(Matrix4x4<Real> const& M, bool* reportInvertibility = nullptr)
{
Matrix4x4<Real> inverse;
bool invertible;
Real a0 = M(0, 0) * M(1, 1) - M(0, 1) * M(1, 0);
Real a1 = M(0, 0) * M(1, 2) - M(0, 2) * M(1, 0);
Real a2 = M(0, 0) * M(1, 3) - M(0, 3) * M(1, 0);
Real a3 = M(0, 1) * M(1, 2) - M(0, 2) * M(1, 1);
Real a4 = M(0, 1) * M(1, 3) - M(0, 3) * M(1, 1);
Real a5 = M(0, 2) * M(1, 3) - M(0, 3) * M(1, 2);
Real b0 = M(2, 0) * M(3, 1) - M(2, 1) * M(3, 0);
Real b1 = M(2, 0) * M(3, 2) - M(2, 2) * M(3, 0);
Real b2 = M(2, 0) * M(3, 3) - M(2, 3) * M(3, 0);
Real b3 = M(2, 1) * M(3, 2) - M(2, 2) * M(3, 1);
Real b4 = M(2, 1) * M(3, 3) - M(2, 3) * M(3, 1);
Real b5 = M(2, 2) * M(3, 3) - M(2, 3) * M(3, 2);
Real det = a0 * b5 - a1 * b4 + a2 * b3 + a3 * b2 - a4 * b1 + a5 * b0;
if (det != (Real)0)
{
Real invDet = (Real)1 / det;
inverse = Matrix4x4<Real>
{
(+M(1, 1) * b5 - M(1, 2) * b4 + M(1, 3) * b3) * invDet,
(-M(0, 1) * b5 + M(0, 2) * b4 - M(0, 3) * b3) * invDet,
(+M(3, 1) * a5 - M(3, 2) * a4 + M(3, 3) * a3) * invDet,
(-M(2, 1) * a5 + M(2, 2) * a4 - M(2, 3) * a3) * invDet,
(-M(1, 0) * b5 + M(1, 2) * b2 - M(1, 3) * b1) * invDet,
(+M(0, 0) * b5 - M(0, 2) * b2 + M(0, 3) * b1) * invDet,
(-M(3, 0) * a5 + M(3, 2) * a2 - M(3, 3) * a1) * invDet,
(+M(2, 0) * a5 - M(2, 2) * a2 + M(2, 3) * a1) * invDet,
(+M(1, 0) * b4 - M(1, 1) * b2 + M(1, 3) * b0) * invDet,
(-M(0, 0) * b4 + M(0, 1) * b2 - M(0, 3) * b0) * invDet,
(+M(3, 0) * a4 - M(3, 1) * a2 + M(3, 3) * a0) * invDet,
(-M(2, 0) * a4 + M(2, 1) * a2 - M(2, 3) * a0) * invDet,
(-M(1, 0) * b3 + M(1, 1) * b1 - M(1, 2) * b0) * invDet,
(+M(0, 0) * b3 - M(0, 1) * b1 + M(0, 2) * b0) * invDet,
(-M(3, 0) * a3 + M(3, 1) * a1 - M(3, 2) * a0) * invDet,
(+M(2, 0) * a3 - M(2, 1) * a1 + M(2, 2) * a0) * invDet
};
invertible = true;
}
else
{
inverse.MakeZero();
invertible = false;
}
if (reportInvertibility)
{
*reportInvertibility = invertible;
}
return inverse;
}
template <typename Real>
Matrix4x4<Real> Adjoint(Matrix4x4<Real> const& M)
{
Real a0 = M(0, 0) * M(1, 1) - M(0, 1) * M(1, 0);
Real a1 = M(0, 0) * M(1, 2) - M(0, 2) * M(1, 0);
Real a2 = M(0, 0) * M(1, 3) - M(0, 3) * M(1, 0);
Real a3 = M(0, 1) * M(1, 2) - M(0, 2) * M(1, 1);
Real a4 = M(0, 1) * M(1, 3) - M(0, 3) * M(1, 1);
Real a5 = M(0, 2) * M(1, 3) - M(0, 3) * M(1, 2);
Real b0 = M(2, 0) * M(3, 1) - M(2, 1) * M(3, 0);
Real b1 = M(2, 0) * M(3, 2) - M(2, 2) * M(3, 0);
Real b2 = M(2, 0) * M(3, 3) - M(2, 3) * M(3, 0);
Real b3 = M(2, 1) * M(3, 2) - M(2, 2) * M(3, 1);
Real b4 = M(2, 1) * M(3, 3) - M(2, 3) * M(3, 1);
Real b5 = M(2, 2) * M(3, 3) - M(2, 3) * M(3, 2);
return Matrix4x4<Real>
{
+M(1, 1) * b5 - M(1, 2) * b4 + M(1, 3) * b3,
-M(0, 1) * b5 + M(0, 2) * b4 - M(0, 3) * b3,
+M(3, 1) * a5 - M(3, 2) * a4 + M(3, 3) * a3,
-M(2, 1) * a5 + M(2, 2) * a4 - M(2, 3) * a3,
-M(1, 0) * b5 + M(1, 2) * b2 - M(1, 3) * b1,
+M(0, 0) * b5 - M(0, 2) * b2 + M(0, 3) * b1,
-M(3, 0) * a5 + M(3, 2) * a2 - M(3, 3) * a1,
+M(2, 0) * a5 - M(2, 2) * a2 + M(2, 3) * a1,
+M(1, 0) * b4 - M(1, 1) * b2 + M(1, 3) * b0,
-M(0, 0) * b4 + M(0, 1) * b2 - M(0, 3) * b0,
+M(3, 0) * a4 - M(3, 1) * a2 + M(3, 3) * a0,
-M(2, 0) * a4 + M(2, 1) * a2 - M(2, 3) * a0,
-M(1, 0) * b3 + M(1, 1) * b1 - M(1, 2) * b0,
+M(0, 0) * b3 - M(0, 1) * b1 + M(0, 2) * b0,
-M(3, 0) * a3 + M(3, 1) * a1 - M(3, 2) * a0,
+M(2, 0) * a3 - M(2, 1) * a1 + M(2, 2) * a0
};
}
template <typename Real>
Real Determinant(Matrix4x4<Real> const& M)
{
Real a0 = M(0, 0) * M(1, 1) - M(0, 1) * M(1, 0);
Real a1 = M(0, 0) * M(1, 2) - M(0, 2) * M(1, 0);
Real a2 = M(0, 0) * M(1, 3) - M(0, 3) * M(1, 0);
Real a3 = M(0, 1) * M(1, 2) - M(0, 2) * M(1, 1);
Real a4 = M(0, 1) * M(1, 3) - M(0, 3) * M(1, 1);
Real a5 = M(0, 2) * M(1, 3) - M(0, 3) * M(1, 2);
Real b0 = M(2, 0) * M(3, 1) - M(2, 1) * M(3, 0);
Real b1 = M(2, 0) * M(3, 2) - M(2, 2) * M(3, 0);
Real b2 = M(2, 0) * M(3, 3) - M(2, 3) * M(3, 0);
Real b3 = M(2, 1) * M(3, 2) - M(2, 2) * M(3, 1);
Real b4 = M(2, 1) * M(3, 3) - M(2, 3) * M(3, 1);
Real b5 = M(2, 2) * M(3, 3) - M(2, 3) * M(3, 2);
Real det = a0 * b5 - a1 * b4 + a2 * b3 + a3 * b2 - a4 * b1 + a5 * b0;
return det;
}
template <typename Real>
Real Trace(Matrix4x4<Real> const& M)
{
Real trace = M(0, 0) + M(1, 1) + M(2, 2) + M(3, 3);
return trace;
}
// Multiply M and V according to the user-selected convention. If it is
// GTE_USE_MAT_VEC, the function returns M*V. If it is GTE_USE_VEC_MAT,
// the function returns V*M. This function is provided to hide the
// preprocessor symbols in the GTEngine sample applications.
template <typename Real>
Vector4<Real> DoTransform(Matrix4x4<Real> const& M, Vector4<Real> const& V)
{
#if defined(GTE_USE_MAT_VEC)
return M * V;
#else
return V * M;
#endif
}
template <typename Real>
Matrix4x4<Real> DoTransform(Matrix4x4<Real> const& A, Matrix4x4<Real> const& B)
{
#if defined(GTE_USE_MAT_VEC)
return A * B;
#else
return B * A;
#endif
}
// For GTE_USE_MAT_VEC, the columns of an invertible matrix form a basis
// for the range of the matrix. For GTE_USE_VEC_MAT, the rows of an
// invertible matrix form a basis for the range of the matrix. These
// functions allow you to access the basis vectors. The caller is
// responsible for ensuring that the matrix is invertible (although the
// inverse is not calculated by these functions).
template <typename Real>
void SetBasis(Matrix4x4<Real>& M, int i, Vector4<Real> const& V)
{
#if defined(GTE_USE_MAT_VEC)
return M.SetCol(i, V);
#else
return M.SetRow(i, V);
#endif
}
template <typename Real>
Vector4<Real> GetBasis(Matrix4x4<Real> const& M, int i)
{
#if defined(GTE_USE_MAT_VEC)
return M.GetCol(i);
#else
return M.GetRow(i);
#endif
}
// Special matrices. In the comments, the matrices are shown using the
// GTE_USE_MAT_VEC multiplication convention.
// The projection plane is Dot(N,X-P) = 0 where N is a 3-by-1 unit-length
// normal vector and P is a 3-by-1 point on the plane. The projection is
// oblique to the plane, in the direction of the 3-by-1 vector D.
// Necessarily Dot(N,D) is not zero for this projection to make sense.
// Given a 3-by-1 point U, compute the intersection of the line U+t*D with
// the plane to obtain t = -Dot(N,U-P)/Dot(N,D); then
//
// projection(U) = P + [I - D*N^T/Dot(N,D)]*(U-P)
//
// A 4-by-4 homogeneous transformation representing the projection is
//
// +- -+
// M = | D*N^T - Dot(N,D)*I -Dot(N,P)D |
// | 0^T -Dot(N,D) |
// +- -+
//
// where M applies to [U^T 1]^T by M*[U^T 1]^T. The matrix is chosen so
// that M[3][3] > 0 whenever Dot(N,D) < 0; the projection is onto the
// "positive side" of the plane.
template <typename Real>
Matrix4x4<Real> MakeObliqueProjection(Vector4<Real> const& origin,
Vector4<Real> const& normal, Vector4<Real> const& direction)
{
Matrix4x4<Real> M;
Real const zero = (Real)0;
Real dotND = Dot(normal, direction);
Real dotNO = Dot(origin, normal);
#if defined(GTE_USE_MAT_VEC)
M(0, 0) = direction[0] * normal[0] - dotND;
M(0, 1) = direction[0] * normal[1];
M(0, 2) = direction[0] * normal[2];
M(0, 3) = -dotNO * direction[0];
M(1, 0) = direction[1] * normal[0];
M(1, 1) = direction[1] * normal[1] - dotND;
M(1, 2) = direction[1] * normal[2];
M(1, 3) = -dotNO * direction[1];
M(2, 0) = direction[2] * normal[0];
M(2, 1) = direction[2] * normal[1];
M(2, 2) = direction[2] * normal[2] - dotND;
M(2, 3) = -dotNO * direction[2];
M(3, 0) = zero;
M(3, 1) = zero;
M(3, 2) = zero;
M(3, 3) = -dotND;
#else
M(0, 0) = direction[0] * normal[0] - dotND;
M(1, 0) = direction[0] * normal[1];
M(2, 0) = direction[0] * normal[2];
M(3, 0) = -dotNO * direction[0];
M(0, 1) = direction[1] * normal[0];
M(1, 1) = direction[1] * normal[1] - dotND;
M(2, 1) = direction[1] * normal[2];
M(3, 1) = -dotNO * direction[1];
M(0, 2) = direction[2] * normal[0];
M(1, 2) = direction[2] * normal[1];
M(2, 2) = direction[2] * normal[2] - dotND;
M(3, 2) = -dotNO * direction[2];
M(0, 2) = zero;
M(1, 3) = zero;
M(2, 3) = zero;
M(3, 3) = -dotND;
#endif
return M;
}
// The perspective projection of a point onto a plane is
//
// +- -+
// M = | Dot(N,E-P)*I - E*N^T -(Dot(N,E-P)*I - E*N^T)*E |
// | -N^t Dot(N,E) |
// +- -+
//
// where E is the eye point, P is a point on the plane, and N is a
// unit-length plane normal.
template <typename Real>
Matrix4x4<Real> MakePerspectiveProjection(Vector4<Real> const& origin,
Vector4<Real> const& normal, Vector4<Real> const& eye)
{
Matrix4x4<Real> M;
Real dotND = Dot(normal, eye - origin);
#if defined(GTE_USE_MAT_VEC)
M(0, 0) = dotND - eye[0] * normal[0];
M(0, 1) = -eye[0] * normal[1];
M(0, 2) = -eye[0] * normal[2];
M(0, 3) = -(M(0, 0) * eye[0] + M(0, 1) * eye[1] + M(0, 2) * eye[2]);
M(1, 0) = -eye[1] * normal[0];
M(1, 1) = dotND - eye[1] * normal[1];
M(1, 2) = -eye[1] * normal[2];
M(1, 3) = -(M(1, 0) * eye[0] + M(1, 1) * eye[1] + M(1, 2) * eye[2]);
M(2, 0) = -eye[2] * normal[0];
M(2, 1) = -eye[2] * normal[1];
M(2, 2) = dotND - eye[2] * normal[2];
M(2, 3) = -(M(2, 0) * eye[0] + M(2, 1) * eye[1] + M(2, 2) * eye[2]);
M(3, 0) = -normal[0];
M(3, 1) = -normal[1];
M(3, 2) = -normal[2];
M(3, 3) = Dot(eye, normal);
#else
M(0, 0) = dotND - eye[0] * normal[0];
M(1, 0) = -eye[0] * normal[1];
M(2, 0) = -eye[0] * normal[2];
M(3, 0) = -(M(0, 0) * eye[0] + M(0, 1) * eye[1] + M(0, 2) * eye[2]);
M(0, 1) = -eye[1] * normal[0];
M(1, 1) = dotND - eye[1] * normal[1];
M(2, 1) = -eye[1] * normal[2];
M(3, 1) = -(M(1, 0) * eye[0] + M(1, 1) * eye[1] + M(1, 2) * eye[2]);
M(0, 2) = -eye[2] * normal[0];
M(1, 2) = -eye[2] * normal[1];
M(2, 2) = dotND - eye[2] * normal[2];
M(3, 2) = -(M(2, 0) * eye[0] + M(2, 1) * eye[1] + M(2, 2) * eye[2]);
M(0, 3) = -normal[0];
M(1, 3) = -normal[1];
M(2, 3) = -normal[2];
M(3, 3) = Dot(eye, normal);
#endif
return M;
}
// The reflection of a point through a plane is
// +- -+
// M = | I-2*N*N^T 2*Dot(N,P)*N |
// | 0^T 1 |
// +- -+
//
// where P is a point on the plane and N is a unit-length plane normal.
template <typename Real>
Matrix4x4<Real> MakeReflection(Vector4<Real> const& origin,
Vector4<Real> const& normal)
{
Matrix4x4<Real> M;
Real const zero = (Real)0, one = (Real)1, two = (Real)2;
Real twoDotNO = two * Dot(origin, normal);
#if defined(GTE_USE_MAT_VEC)
M(0, 0) = one - two * normal[0] * normal[0];
M(0, 1) = -two * normal[0] * normal[1];
M(0, 2) = -two * normal[0] * normal[2];
M(0, 3) = twoDotNO * normal[0];
M(1, 0) = M(0, 1);
M(1, 1) = one - two * normal[1] * normal[1];
M(1, 2) = -two * normal[1] * normal[2];
M(1, 3) = twoDotNO * normal[1];
M(2, 0) = M(0, 2);
M(2, 1) = M(1, 2);
M(2, 2) = one - two * normal[2] * normal[2];
M(2, 3) = twoDotNO * normal[2];
M(3, 0) = zero;
M(3, 1) = zero;
M(3, 2) = zero;
M(3, 3) = one;
#else
M(0, 0) = one - two * normal[0] * normal[0];
M(1, 0) = -two * normal[0] * normal[1];
M(2, 0) = -two * normal[0] * normal[2];
M(3, 0) = twoDotNO * normal[0];
M(0, 1) = M(1, 0);
M(1, 1) = one - two * normal[1] * normal[1];
M(2, 1) = -two * normal[1] * normal[2];
M(3, 1) = twoDotNO * normal[1];
M(0, 2) = M(2, 0);
M(1, 2) = M(2, 1);
M(2, 2) = one - two * normal[2] * normal[2];
M(3, 2) = twoDotNO * normal[2];
M(0, 3) = zero;
M(1, 3) = zero;
M(2, 3) = zero;
M(3, 3) = one;
#endif
return M;
}
}