/// <summary>Attempts to invert the given matrix. If the operation succeeds, the inverted matrix is stored in the result parameter.</summary>
/// <param name="matrix">The source matrix.</param>
/// <param name="result">The output matrix.</param>
/// <returns>True if the operation succeeded, False otherwise.</returns>
public static bool Invert <T>(Matrix3X2 <T> matrix, out Matrix3X2 <T> result)
where T : unmanaged, IFormattable, IEquatable <T>, IComparable <T>
{
T det = Scalar.Subtract(Scalar.Multiply(matrix.M11, matrix.M22), Scalar.Multiply(matrix.M21, matrix.M12));
if (!Scalar.GreaterThanOrEqual(Scalar.Abs(det), Scalar <T> .Epsilon))
{
result = new(Scalar <T> .NaN, Scalar <T> .NaN, Scalar <T> .NaN, Scalar <T> .NaN, Scalar <T> .NaN, Scalar <T> .NaN);
return(false);
}
T invDet = Scalar.Reciprocal(det);
result = default;
result.M11 = Scalar.Multiply(matrix.M22, invDet);
result.M12 = Scalar.Negate(Scalar.Multiply(matrix.M12, invDet));
result.M21 = Scalar.Negate(Scalar.Multiply(matrix.M21, invDet));
result.M22 = Scalar.Multiply(matrix.M11, invDet);
result.M31 = Scalar.Multiply(Scalar.Subtract(Scalar.Multiply(matrix.M21, matrix.M32), Scalar.Multiply(matrix.M31, matrix.M22)), invDet);
result.M32 = Scalar.Multiply(Scalar.Subtract(Scalar.Multiply(matrix.M31, matrix.M12), Scalar.Multiply(matrix.M11, matrix.M32)), invDet);
return(true);
}
/// <summary>Creates a skew matrix from the given angles in radians and a center point.</summary>
/// <param name="radiansX">The X angle, in radians.</param>
/// <param name="radiansY">The Y angle, in radians.</param>
/// <param name="centerPoint">The center point.</param>
/// <returns>A skew matrix.</returns>
public static Matrix3X2 <T> CreateSkew <T>(T radiansX, T radiansY, Vector2D <T> centerPoint)
where T : unmanaged, IFormattable, IEquatable <T>, IComparable <T>
{
Matrix3X2 <T> result = Matrix3X2 <T> .Identity;
T xTan = Scalar.Tan(radiansX);
T yTan = Scalar.Tan(radiansY);
T tx = Scalar.Negate(Scalar.Multiply(centerPoint.Y, xTan));
T ty = Scalar.Negate(Scalar.Multiply(centerPoint.X, yTan));
result.M12 = yTan;
result.M21 = xTan;
result.M31 = tx;
result.M32 = ty;
return(result);
}
/// <summary>Creates a matrix for rotating points around the Z-axis.</summary>
/// <param name="radians">The amount, in radians, by which to rotate around the Z-axis.</param>
/// <returns>The rotation matrix.</returns>
public static Matrix3X3 <T> CreateRotationZ <T>(T radians)
where T : unmanaged, IFormattable, IEquatable <T>, IComparable <T>
{
Matrix3X3 <T> result = Matrix3X3 <T> .Identity;
T c = Scalar.Cos(radians);
T s = Scalar.Sin(radians);
// [ c s 0 0 ]
// [ -s c 0 0 ]
// [ 0 0 1 0 ]
// [ 0 0 0 1 ]
result.M11 = c;
result.M12 = s;
result.M21 = Scalar.Negate(s);
result.M22 = c;
return(result);
}
/// <summary>Creates a matrix for rotating points around the Y-axis.</summary>
/// <param name="radians">The amount, in radians, by which to rotate around the Y-axis.</param>
/// <returns>The rotation matrix.</returns>
public static Matrix3X3 <T> CreateRotationY <T>(T radians)
where T : unmanaged, IFormattable, IEquatable <T>, IComparable <T>
{
Matrix3X3 <T> result = Matrix3X3 <T> .Identity;
T c = Scalar.Cos(radians);
T s = Scalar.Sin(radians);
// [ c 0 -s 0 ]
// [ 0 1 0 0 ]
// [ s 0 c 0 ]
// [ 0 0 0 1 ]
result.M11 = c;
result.M13 = Scalar.Negate(s);
result.M31 = s;
result.M33 = c;
return(result);
}
public static Plane <T> CreateFromVertices <T>(Vector3D <T> point1, Vector3D <T> point2, Vector3D <T> point3)
where T : unmanaged, IFormattable, IEquatable <T>, IComparable <T>
{
var a = point1;
var b = point2;
var c = point3;
var ab = b - a;
var ac = c - a;
var cross = Vector3D.Cross(ab, ac);
Plane <T> p;
p.Normal = cross;
p.Distance = Scalar.Negate(Scalar.Add(
Scalar.Add(Scalar.Multiply(p.Normal.X, a.X), Scalar.Multiply(p.Normal.Y, a.Y)),
Scalar.Multiply(p.Normal.Z, a.Z)));
return(p);
/*if (Vector.IsHardwareAccelerated)
* {
* Vector3D<T> a = point2 - point1;
* Vector3D<T> b = point3 - point1;
*
* // N = Cross(a, b)
* Vector3D<T> n = Vector3D.Cross(a, b);
* Vector3D<T> normal = Vector3D.Normalize(n);
*
* // D = - Dot(N, point1)
* T d = Scalar.Negate(Vector3D.Dot(normal, point1));
*
* return new Plane<T>(normal, d);
* }
* else
* {
* T ax = Scalar.Subtract(point2.X, point1.X);
* T ay = Scalar.Subtract(point2.Y, point1.Y);
* T az = Scalar.Subtract(point2.Z, point1.Z);
*
* T bx = Scalar.Subtract(point3.X, point1.X);
* T by = Scalar.Subtract(point3.Y, point1.Y);
* T bz = Scalar.Subtract(point3.Z, point1.Z);
*
* // N=Cross(a,b)
* T nx = Scalar.Subtract(Scalar.Multiply(ay, bz), Scalar.Multiply(az, by));
* T ny = Scalar.Subtract(Scalar.Multiply(az, bx), Scalar.Multiply(ax, bz));
* T nz = Scalar.Subtract(Scalar.Multiply(ax, by), Scalar.Multiply(ay, bx));
*
* // Normalize(N)
* T ls = Scalar.Add(Scalar.Add(Scalar.Multiply(nx, nx), Scalar.Multiply(ny, ny)), Scalar.Multiply(nz, nz));
* T invNorm = Scalar.Inverse(Scalar.Sqrt(ls));
*
* Vector3D<T> normal = new Vector3D<T>(
* Scalar.Multiply(nx, invNorm),
* Scalar.Multiply(ny, invNorm),
* Scalar.Multiply(nz, invNorm));
*
* return new(normal,
* Scalar.Negate(Scalar.Add(
* Scalar.Add(Scalar.Multiply(normal.X, point1.X),
* Scalar.Multiply(normal.Y, point1.Y)), Scalar.Multiply(normal.Z, point1.Z))));
* }*/
}
/// <summary>Creates a rotation matrix using the given rotation in radians.</summary>
/// <param name="radians">The amount of rotation, in radians.</param>
/// <returns>A rotation matrix.</returns>
public static Matrix3X2 <T> CreateRotation <T>(T radians)
where T : unmanaged, IFormattable, IEquatable <T>, IComparable <T>
{
radians = Scalar.IEEERemainder(radians, Scalar <T> .Tau);
T c, s;
if (Scalar.GreaterThan(radians, Scalar.As <float, T>(-RotationEpsilon)) && !Scalar.GreaterThanOrEqual(radians, Scalar.As <float, T>(RotationEpsilon)))
{
// Exact case for zero rotation.
c = Scalar <T> .One;
s = Scalar <T> .Zero;
}
else if (Scalar.GreaterThan(radians, Scalar.As <float, T>(
#if MATHF
MathF.PI
#else
((float)Math.PI)
#endif
/ 2 - RotationEpsilon)) && !Scalar.GreaterThanOrEqual(radians, Scalar.As <float, T>(
#if MATHF
MathF.PI
#else
((float)Math.PI)
#endif
/ 2 + RotationEpsilon)))
{
// Exact case for 90 degree rotation.
c = Scalar <T> .Zero;
s = Scalar <T> .One;
}
else if (!Scalar.GreaterThanOrEqual(radians, Scalar.As <float, T>(-
#if MATHF
MathF.PI
#else
((float)Math.PI)
#endif
+ RotationEpsilon)) || Scalar.GreaterThan(radians, Scalar.As <float, T>(
#if MATHF
MathF.PI
#else
((float)Math.PI)
#endif
- RotationEpsilon)))
{
// Exact case for 180 degree rotation.
c = Scalar <T> .MinusOne;
s = Scalar <T> .Zero;
}
else if (Scalar.GreaterThan(radians, Scalar.As <float, T>(-
#if MATHF
MathF.PI
#else
((float)Math.PI)
#endif
/ 2 - RotationEpsilon)) && !Scalar.GreaterThanOrEqual(radians, Scalar.As <float, T>(-
#if MATHF
MathF.PI
#else
((float)Math.PI)
#endif
/ 2 + RotationEpsilon)))
{
// Exact case for 270 degree rotation.
c = Scalar <T> .Zero;
s = Scalar <T> .MinusOne;
}
else
{
// Arbitrary rotation.
c = Scalar.Cos(radians);
s = Scalar.Sin(radians);
}
// [ c s ]
// [ -s c ]
// [ 0 0 ]
Matrix3X2 <T> result = Matrix3X2 <T> .Identity;
result.M11 = c;
result.M12 = s;
result.M21 = Scalar.Negate(s);
result.M22 = c;
return(result);
}
/// <summary>Creates a rotation matrix using the given rotation in radians and a center point.</summary>
/// <param name="radians">The amount of rotation, in radians.</param>
/// <param name="centerPoint">The center point.</param>
/// <returns>A rotation matrix.</returns>
public static Matrix3X2 <T> CreateRotation <T>(T radians, Vector2D <T> centerPoint)
where T : unmanaged, IFormattable, IEquatable <T>, IComparable <T>
{
radians = Scalar.IEEERemainder(radians, Scalar <T> .Tau);
T c, s;
if (Scalar.GreaterThan(radians, Scalar.As <float, T>(-RotationEpsilon)) && !Scalar.GreaterThanOrEqual(radians, Scalar.As <float, T>(RotationEpsilon)))
{
// Exact case for zero rotation.
c = Scalar <T> .One;
s = Scalar <T> .Zero;
}
else if (Scalar.GreaterThan(radians, Scalar.As <float, T>(
#if MATHF
MathF.PI
#else
((float)Math.PI)
#endif
/ 2 - RotationEpsilon)) && !Scalar.GreaterThanOrEqual(radians, Scalar.As <float, T>(
#if MATHF
MathF.PI
#else
((float)Math.PI)
#endif
/ 2 + RotationEpsilon)))
{
// Exact case for 90 degree rotation.
c = Scalar <T> .Zero;
s = Scalar <T> .One;
}
else if (!Scalar.GreaterThanOrEqual(radians, Scalar.As <float, T>(-
#if MATHF
MathF.PI
#else
((float)Math.PI)
#endif
+ RotationEpsilon)) || Scalar.GreaterThan(radians, Scalar.As <float, T>(
#if MATHF
MathF.PI
#else
((float)Math.PI)
#endif
- RotationEpsilon)))
{
// Exact case for 180 degree rotation.
c = Scalar <T> .MinusOne;
s = Scalar <T> .Zero;
}
else if (Scalar.GreaterThan(radians, Scalar.As <float, T>(-
#if MATHF
MathF.PI
#else
((float)Math.PI)
#endif
/ 2 - RotationEpsilon)) && !Scalar.GreaterThanOrEqual(radians, Scalar.As <float, T>(-
#if MATHF
MathF.PI
#else
((float)Math.PI)
#endif
/ 2 + RotationEpsilon)))
{
// Exact case for 270 degree rotation.
c = Scalar <T> .Zero;
s = Scalar <T> .MinusOne;
}
else
{
// Arbitrary rotation.
c = Scalar.Cos(radians);
s = Scalar.Sin(radians);
}
T x = Scalar.Add(Scalar.Multiply(centerPoint.X, Scalar.Subtract(Scalar <T> .One, c)), Scalar.Multiply(centerPoint.Y, s));
T y = Scalar.Subtract(Scalar.Multiply(centerPoint.Y, Scalar.Subtract(Scalar <T> .One, c)), Scalar.Multiply(centerPoint.X, s));
// [ c s ]
// [ -s c ]
// [ x y ]
return(new(
new(c, s),
new(Scalar.Negate(s), c),
new(x, y)));
}
/// <summary>Attempts to extract the scale, translation, and rotation components from the given scale/rotation/translation matrix.
/// If successful, the out parameters will contained the extracted values.</summary>
/// <param name="matrix">The source matrix.</param>
/// <param name="scale">The scaling component of the transformation matrix.</param>
/// <param name="rotation">The rotation component of the transformation matrix.</param>
/// <returns>True if the source matrix was successfully decomposed; False otherwise.</returns>
public static bool Decompose <T>(Matrix3X3 <T> matrix, out Vector3D <T> scale, out Quaternion <T> rotation)
where T : unmanaged, IFormattable, IEquatable <T>, IComparable <T>
{
bool result = true;
unsafe
{
fixed(Vector3D <T> *scaleBase = &scale)
{
T *pfScales = (T *)scaleBase;
T det;
VectorBasis <T> vectorBasis;
Vector3D <T> ** pVectorBasis = (Vector3D <T> **) & vectorBasis;
Matrix3X3 <T> matTemp = Matrix3X3 <T> .Identity;
CanonicalBasis <T> canonicalBasis = default;
Vector3D <T> * pCanonicalBasis = &canonicalBasis.Row0;
canonicalBasis.Row0 = new Vector3D <T>(Scalar <T> .One, Scalar <T> .Zero, Scalar <T> .Zero);
canonicalBasis.Row1 = new Vector3D <T>(Scalar <T> .Zero, Scalar <T> .One, Scalar <T> .Zero);
canonicalBasis.Row2 = new Vector3D <T>(Scalar <T> .Zero, Scalar <T> .Zero, Scalar <T> .One);
pVectorBasis[0] = &matTemp.Row1;
pVectorBasis[1] = &matTemp.Row2;
pVectorBasis[2] = &matTemp.Row3;
*(pVectorBasis[0]) = new Vector3D <T>(matrix.M11, matrix.M12, matrix.M13);
*(pVectorBasis[1]) = new Vector3D <T>(matrix.M21, matrix.M22, matrix.M23);
*(pVectorBasis[2]) = new Vector3D <T>(matrix.M31, matrix.M32, matrix.M33);
scale.X = pVectorBasis[0]->Length;
scale.Y = pVectorBasis[1]->Length;
scale.Z = pVectorBasis[2]->Length;
uint a, b, c;
#region Ranking
T x = pfScales[0], y = pfScales[1], z = pfScales[2];
if (!Scalar.GreaterThanOrEqual(x, y))
{
if (!Scalar.GreaterThanOrEqual(y, z))
{
a = 2;
b = 1;
c = 0;
}
else
{
a = 1;
if (!Scalar.GreaterThanOrEqual(x, z))
{
b = 2;
c = 0;
}
else
{
b = 0;
c = 2;
}
}
}
else
{
if (!Scalar.GreaterThanOrEqual(x, z))
{
a = 2;
b = 0;
c = 1;
}
else
{
a = 0;
if (!Scalar.GreaterThanOrEqual(y, z))
{
b = 2;
c = 1;
}
else
{
b = 1;
c = 2;
}
}
}
#endregion
if (!Scalar.GreaterThanOrEqual(pfScales[a], Scalar.As <float, T>(DecomposeEpsilon)))
{
*(pVectorBasis[a]) = pCanonicalBasis[a];
}
*pVectorBasis[a] = Vector3D.Normalize(*pVectorBasis[a]);
if (!Scalar.GreaterThanOrEqual(pfScales[b], Scalar.As <float, T>(DecomposeEpsilon)))
{
uint cc;
T fAbsX, fAbsY, fAbsZ;
fAbsX = Scalar.Abs(pVectorBasis[a]->X);
fAbsY = Scalar.Abs(pVectorBasis[a]->Y);
fAbsZ = Scalar.Abs(pVectorBasis[a]->Z);
#region Ranking
if (!Scalar.GreaterThanOrEqual(fAbsX, fAbsY))
{
if (!Scalar.GreaterThanOrEqual(fAbsY, fAbsZ))
{
cc = 0;
}
else
{
if (!Scalar.GreaterThanOrEqual(fAbsX, fAbsZ))
{
cc = 0;
}
else
{
cc = 2;
}
}
}
else
{
if (!Scalar.GreaterThanOrEqual(fAbsX, fAbsZ))
{
cc = 1;
}
else
{
if (!Scalar.GreaterThanOrEqual(fAbsY, fAbsZ))
{
cc = 1;
}
else
{
cc = 2;
}
}
}
#endregion
*pVectorBasis[b] = Vector3D.Cross(*pVectorBasis[a], *(pCanonicalBasis + cc));
}
*pVectorBasis[b] = Vector3D.Normalize(*pVectorBasis[b]);
if (!Scalar.GreaterThanOrEqual(pfScales[c], Scalar.As <float, T>(DecomposeEpsilon)))
{
*pVectorBasis[c] = Vector3D.Cross(*pVectorBasis[a], *pVectorBasis[b]);
}
*pVectorBasis[c] = Vector3D.Normalize(*pVectorBasis[c]);
det = matTemp.GetDeterminant();
// use Kramer's rule to check for handedness of coordinate system
if (!Scalar.GreaterThanOrEqual(det, Scalar <T> .Zero))
{
// switch coordinate system by negating the scale and inverting the basis vector on the x-axis
pfScales[a] = Scalar.Negate(pfScales[a]);
*pVectorBasis[a] = -(*pVectorBasis[a]);
det = Scalar.Negate(det);
}
det = Scalar.Subtract(det, Scalar <T> .One);
det = Scalar.Multiply(det, det);
if (!Scalar.GreaterThanOrEqual(Scalar.As <float, T>(DecomposeEpsilon), det))
{
// Non-SRT matrix encountered
rotation = Quaternion <T> .Identity;
result = false;
}
else
{
// generate the quaternion from the matrix
rotation = Quaternion <T> .CreateFromRotationMatrix(matTemp);
}
}
}
return(result);
}
