public bool Compare(ref idMat2 a)
{
idVec2[] a_mat = a.mat;
return(
mat[0].Compare(ref a_mat[0]) &&
mat[1].Compare(ref a_mat[1]));
}
public bool Compare(ref idMat2 a, float epsilon)
{
idVec2[] a_mat = a.mat;
return(
mat[0].Compare(ref a_mat[0], epsilon) &&
mat[1].Compare(ref a_mat[1], epsilon));
}
public idMat2 opAdd(idMat2 a)
{
idVec2[] a_mat = a.mat;
mat[0].x += a_mat[0].x; mat[0].y += a_mat[0].y;
mat[1].x += a_mat[1].x; mat[1].y += a_mat[1].y;
return(this);
}
public idMat2 opSub(idMat2 a)
{
idVec2[] a_mat = a.mat;
mat[0].x -= a_mat[0].x; mat[0].y -= a_mat[0].y;
mat[1].x -= a_mat[1].x; mat[1].y -= a_mat[1].y;
return(this);
}
public idMat2 InverseFast()
{
idMat2 invMat = this;
bool r = invMat.InverseFastSelf();
Debug.Assert(r);
return(invMat);
}
public idMat2 opMul(idMat2 a)
{
idVec2[] a_mat = a.mat;
float x, y;
x = mat[0].x; y = mat[0].y;
mat[0].x = x * a_mat[0].x + y * a_mat[1].x;
mat[0].y = x * a_mat[0].y + y * a_mat[1].y;
x = mat[1].x; y = mat[1].y;
mat[1].x = x * a_mat[0].x + y * a_mat[1].x;
mat[1].y = x * a_mat[0].y + y * a_mat[1].y;
return(this);
}
public bool InverseFastSelf()
{
#if false
// 84+4+16 = 104 multiplications
// 1 division
// 2x2 sub-determinants required to calculate 4x4 determinant
float det2_01_01 = mat[0].x * mat[1].y - mat[0].y * mat[1].x;
float det2_01_02 = mat[0].x * mat[1].z - mat[0].z * mat[1].x;
float det2_01_03 = mat[0].x * mat[1].w - mat[0].w * mat[1].x;
float det2_01_12 = mat[0].y * mat[1].z - mat[0].z * mat[1].y;
float det2_01_13 = mat[0].y * mat[1].w - mat[0].w * mat[1].y;
float det2_01_23 = mat[0].z * mat[1].w - mat[0].w * mat[1].z;
// 3x3 sub-determinants required to calculate 4x4 determinant
float det3_201_012 = mat[2].x * det2_01_12 - mat[2].y * det2_01_02 + mat[2].z * det2_01_01;
float det3_201_013 = mat[2].x * det2_01_13 - mat[2].y * det2_01_03 + mat[2].w * det2_01_01;
float det3_201_023 = mat[2].x * det2_01_23 - mat[2].z * det2_01_03 + mat[2].w * det2_01_02;
float det3_201_123 = mat[2].y * det2_01_23 - mat[2].z * det2_01_13 + mat[2].w * det2_01_12;
double det = (-det3_201_123 * mat[3].x + det3_201_023 * mat[3].y - det3_201_013 * mat[3].z + det3_201_012 * mat[3].w);
if (idMath.Fabs(det) < MATRIX_INVERSE_EPSILON)
{
return(false);
}
double invDet = 1.0f / det;
// remaining 2x2 sub-determinants
float det2_03_01 = mat[0].x * mat[3].y - mat[0].y * mat[3].x;
float det2_03_02 = mat[0].x * mat[3].z - mat[0].z * mat[3].x;
float det2_03_03 = mat[0].x * mat[3].w - mat[0].w * mat[3].x;
float det2_03_12 = mat[0].y * mat[3].z - mat[0].z * mat[3].y;
float det2_03_13 = mat[0].y * mat[3].w - mat[0].w * mat[3].y;
float det2_03_23 = mat[0].z * mat[3].w - mat[0].w * mat[3].z;
//
float det2_13_01 = mat[1].x * mat[3].y - mat[1].y * mat[3].x;
float det2_13_02 = mat[1].x * mat[3].z - mat[1].z * mat[3].x;
float det2_13_03 = mat[1].x * mat[3].w - mat[1].w * mat[3].x;
float det2_13_12 = mat[1].y * mat[3].z - mat[1].z * mat[3].y;
float det2_13_13 = mat[1].y * mat[3].w - mat[1].w * mat[3].y;
float det2_13_23 = mat[1].z * mat[3].w - mat[1].w * mat[3].z;
// remaining 3x3 sub-determinants
float det3_203_012 = mat[2].x * det2_03_12 - mat[2].y * det2_03_02 + mat[2].z * det2_03_01;
float det3_203_013 = mat[2].x * det2_03_13 - mat[2].y * det2_03_03 + mat[2].w * det2_03_01;
float det3_203_023 = mat[2].x * det2_03_23 - mat[2].z * det2_03_03 + mat[2].w * det2_03_02;
float det3_203_123 = mat[2].y * det2_03_23 - mat[2].z * det2_03_13 + mat[2].w * det2_03_12;
//
float det3_213_012 = mat[2].x * det2_13_12 - mat[2].y * det2_13_02 + mat[2].z * det2_13_01;
float det3_213_013 = mat[2].x * det2_13_13 - mat[2].y * det2_13_03 + mat[2].w * det2_13_01;
float det3_213_023 = mat[2].x * det2_13_23 - mat[2].z * det2_13_03 + mat[2].w * det2_13_02;
float det3_213_123 = mat[2].y * det2_13_23 - mat[2].z * det2_13_13 + mat[2].w * det2_13_12;
//
float det3_301_012 = mat[3].x * det2_01_12 - mat[3].y * det2_01_02 + mat[3].z * det2_01_01;
float det3_301_013 = mat[3].x * det2_01_13 - mat[3].y * det2_01_03 + mat[3].w * det2_01_01;
float det3_301_023 = mat[3].x * det2_01_23 - mat[3].z * det2_01_03 + mat[3].w * det2_01_02;
float det3_301_123 = mat[3].y * det2_01_23 - mat[3].z * det2_01_13 + mat[3].w * det2_01_12;
//
mat[0].x = (float)(-det3_213_123 * invDet);
mat[1].x = (float)(+det3_213_023 * invDet);
mat[2].x = (float)(-det3_213_013 * invDet);
mat[3].x = (float)(+det3_213_012 * invDet);
//
mat[0].y = (float)(+det3_203_123 * invDet);
mat[1].y = (float)(-det3_203_023 * invDet);
mat[2].y = (float)(+det3_203_013 * invDet);
mat[3].y = (float)(-det3_203_012 * invDet);
//
mat[0].z = (float)(+det3_301_123 * invDet);
mat[1].z = (float)(-det3_301_023 * invDet);
mat[2].z = (float)(+det3_301_013 * invDet);
mat[3].z = (float)(-det3_301_012 * invDet);
//
mat[0].w = (float)(-det3_201_123 * invDet);
mat[1].w = (float)(+det3_201_023 * invDet);
mat[2].w = (float)(-det3_201_013 * invDet);
mat[3].w = (float)(+det3_201_012 * invDet);
return(true);
#elif false
// 4*18 = 72 multiplications
// 4 divisions
float *mat = reinterpret_cast <float *>(this);
float s;
double d, di;
di = mat[0];
s = di;
mat[0] = d = 1.0f / di;
mat[1] *= d;
mat[2] *= d;
mat[3] *= d;
d = -d;
mat[4] *= d;
mat[8] *= d;
mat[12] *= d;
d = mat[4] * di;
mat[5] += mat[1] * d;
mat[6] += mat[2] * d;
mat[7] += mat[3] * d;
d = mat[8] * di;
mat[9] += mat[1] * d;
mat[10] += mat[2] * d;
mat[11] += mat[3] * d;
d = mat[12] * di;
mat[13] += mat[1] * d;
mat[14] += mat[2] * d;
mat[15] += mat[3] * d;
di = mat[5];
s *= di;
mat[5] = d = 1.0f / di;
mat[4] *= d;
mat[6] *= d;
mat[7] *= d;
d = -d;
mat[1] *= d;
mat[9] *= d;
mat[13] *= d;
d = mat[1] * di;
mat[0] += mat[4] * d;
mat[2] += mat[6] * d;
mat[3] += mat[7] * d;
d = mat[9] * di;
mat[8] += mat[4] * d;
mat[10] += mat[6] * d;
mat[11] += mat[7] * d;
d = mat[13] * di;
mat[12] += mat[4] * d;
mat[14] += mat[6] * d;
mat[15] += mat[7] * d;
di = mat[10];
s *= di;
mat[10] = d = 1.0f / di;
mat[8] *= d;
mat[9] *= d;
mat[11] *= d;
d = -d;
mat[2] *= d;
mat[6] *= d;
mat[14] *= d;
d = mat[2] * di;
mat[0] += mat[8] * d;
mat[1] += mat[9] * d;
mat[3] += mat[11] * d;
d = mat[6] * di;
mat[4] += mat[8] * d;
mat[5] += mat[9] * d;
mat[7] += mat[11] * d;
d = mat[14] * di;
mat[12] += mat[8] * d;
mat[13] += mat[9] * d;
mat[15] += mat[11] * d;
di = mat[15];
s *= di;
mat[15] = d = 1.0f / di;
mat[12] *= d;
mat[13] *= d;
mat[14] *= d;
d = -d;
mat[3] *= d;
mat[7] *= d;
mat[11] *= d;
d = mat[3] * di;
mat[0] += mat[12] * d;
mat[1] += mat[13] * d;
mat[2] += mat[14] * d;
d = mat[7] * di;
mat[4] += mat[12] * d;
mat[5] += mat[13] * d;
mat[6] += mat[14] * d;
d = mat[11] * di;
mat[8] += mat[12] * d;
mat[9] += mat[13] * d;
mat[10] += mat[14] * d;
return(s != 0.0f && !FLOAT_IS_NAN(s));
#else
// 6*8+2*6 = 60 multiplications
// 2*1 = 2 divisions
float[] mat = this;
// r0 = m0.Inverse();
float det = mat[0 * 4 + 0] * mat[1 * 4 + 1] - mat[0 * 4 + 1] * mat[1 * 4 + 0];
if (idMath.Fabs(det) < MATRIX_INVERSE_EPSILON)
{
return(false);
}
float invDet = 1.0f / det;
idMat2 r0 = new idMat2(); idVec2[] r0_mat = r0.mat;
r0_mat[0].x = mat[1 * 4 + 1] * invDet;
r0_mat[0].y = -mat[0 * 4 + 1] * invDet;
r0_mat[1].x = -mat[1 * 4 + 0] * invDet;
r0_mat[1].y = mat[0 * 4 + 0] * invDet;
// r1 = r0 * m1;
idMat2 r1 = new idMat2(); idVec2[] r1_mat = r1.mat;
r1_mat[0].x = r0_mat[0].x * mat[0 * 4 + 2] + r0_mat[0].y * mat[1 * 4 + 2];
r1_mat[0].y = r0_mat[0].x * mat[0 * 4 + 3] + r0_mat[0].y * mat[1 * 4 + 3];
r1_mat[1].x = r0_mat[1].x * mat[0 * 4 + 2] + r0_mat[1].y * mat[1 * 4 + 2];
r1_mat[1].y = r0_mat[1].x * mat[0 * 4 + 3] + r0_mat[1].y * mat[1 * 4 + 3];
// r2 = m2 * r1;
idMat2 r2 = new idMat2(); idVec2[] r2_mat = r2.mat;
r2_mat[0].x = mat[2 * 4 + 0] * r1_mat[0].x + mat[2 * 4 + 1] * r1_mat[1].x;
r2_mat[0].y = mat[2 * 4 + 0] * r1_mat[0].y + mat[2 * 4 + 1] * r1_mat[1].y;
r2_mat[1].x = mat[3 * 4 + 0] * r1_mat[0].x + mat[3 * 4 + 1] * r1_mat[1].x;
r2_mat[1].y = mat[3 * 4 + 0] * r1_mat[0].y + mat[3 * 4 + 1] * r1_mat[1].y;
// r3 = r2 - m3;
idMat2 r3 = new idMat2(); idVec2[] r3_mat = r3.mat;
r3_mat[0].x = r2_mat[0].x - mat[2 * 4 + 2];
r3_mat[0].y = r2_mat[0].y - mat[2 * 4 + 3];
r3_mat[1].x = r2_mat[1].x - mat[3 * 4 + 2];
r3_mat[1].y = r2_mat[1].y - mat[3 * 4 + 3];
// r3.InverseSelf();
det = r3_mat[0].x * r3_mat[1].y - r3_mat[0].y * r3_mat[1].x;
if (idMath.Fabs(det) < MATRIX_INVERSE_EPSILON)
{
return(false);
}
invDet = 1.0f / det;
float a = r3_mat[0].x;
r3_mat[0].x = r3_mat[1].y * invDet;
r3_mat[0].y = -r3_mat[0].y * invDet;
r3_mat[1].x = -r3_mat[1].x * invDet;
r3_mat[1].y = a * invDet;
// r2 = m2 * r0;
r2_mat[0].x = mat[2 * 4 + 0] * r0_mat[0].x + mat[2 * 4 + 1] * r0_mat[1].x;
r2_mat[0].y = mat[2 * 4 + 0] * r0_mat[0].y + mat[2 * 4 + 1] * r0_mat[1].y;
r2_mat[1].x = mat[3 * 4 + 0] * r0_mat[0].x + mat[3 * 4 + 1] * r0_mat[1].x;
r2_mat[1].y = mat[3 * 4 + 0] * r0_mat[0].y + mat[3 * 4 + 1] * r0_mat[1].y;
// m2 = r3 * r2;
mat[2 * 4 + 0] = r3_mat[0].x * r2_mat[0].x + r3_mat[0].y * r2_mat[1].x;
mat[2 * 4 + 1] = r3_mat[0].x * r2_mat[0].y + r3_mat[0].y * r2_mat[1].y;
mat[3 * 4 + 0] = r3_mat[1].x * r2_mat[0].x + r3_mat[1].y * r2_mat[1].x;
mat[3 * 4 + 1] = r3_mat[1].x * r2_mat[0].y + r3_mat[1].y * r2_mat[1].y;
// m0 = r0 - r1 * m2;
mat[0 * 4 + 0] = r0_mat[0].x - r1_mat[0].x * mat[2 * 4 + 0] - r1_mat[0].y * mat[3 * 4 + 0];
mat[0 * 4 + 1] = r0_mat[0].y - r1_mat[0].x * mat[2 * 4 + 1] - r1_mat[0].y * mat[3 * 4 + 1];
mat[1 * 4 + 0] = r0_mat[1].x - r1_mat[1].x * mat[2 * 4 + 0] - r1_mat[1].y * mat[3 * 4 + 0];
mat[1 * 4 + 1] = r0_mat[1].y - r1_mat[1].x * mat[2 * 4 + 1] - r1_mat[1].y * mat[3 * 4 + 1];
// m1 = r1 * r3;
mat[0 * 4 + 2] = r1_mat[0].x * r3_mat[0].x + r1_mat[0].x * r3_mat[1].x;
mat[0 * 4 + 3] = r1_mat[0].x * r3_mat[0].y + r1_mat[0].x * r3_mat[1].y;
mat[1 * 4 + 2] = r1_mat[1].x * r3_mat[0].x + r1_mat[1].x * r3_mat[1].x;
mat[1 * 4 + 3] = r1_mat[1].x * r3_mat[0].y + r1_mat[1].x * r3_mat[1].y;
// m3 = -r3;
mat[2 * 4 + 2] = -r3_mat[0].x;
mat[2 * 4 + 3] = -r3_mat[0].y;
mat[3 * 4 + 2] = -r3_mat[1].x;
mat[3 * 4 + 3] = -r3_mat[1].y;
return(true);
#endif
}
public idMat2 opMul(idMat2 a)
{
idVec2[] a_mat = a.mat;
float x, y;
x = mat[0].x; y = mat[0].y;
mat[0].x = x * a_mat[0].x + y * a_mat[1].x;
mat[0].y = x * a_mat[0].y + y * a_mat[1].y;
x = mat[1].x; y = mat[1].y;
mat[1].x = x * a_mat[0].x + y * a_mat[1].x;
mat[1].y = x * a_mat[0].y + y * a_mat[1].y;
return this;
}
public bool Compare(ref idMat2 a, float epsilon)
{
idVec2[] a_mat = a.mat;
return (
mat[0].Compare(ref a_mat[0], epsilon) &&
mat[1].Compare(ref a_mat[1], epsilon));
}
public bool Compare(ref idMat2 a)
{
idVec2[] a_mat = a.mat;
return (
mat[0].Compare(ref a_mat[0]) &&
mat[1].Compare(ref a_mat[1]));
}
public idMat2 opSub(idMat2 a)
{
idVec2[] a_mat = a.mat;
mat[0].x -= a_mat[0].x; mat[0].y -= a_mat[0].y;
mat[1].x -= a_mat[1].x; mat[1].y -= a_mat[1].y;
return this;
}
public idMat2 opAdd(idMat2 a)
{
idVec2[] a_mat = a.mat;
mat[0].x += a_mat[0].x; mat[0].y += a_mat[0].y;
mat[1].x += a_mat[1].x; mat[1].y += a_mat[1].y;
return this;
}
public bool InverseFastSelf()
{
#if false
// 84+4+16 = 104 multiplications
// 1 division
// 2x2 sub-determinants required to calculate 4x4 determinant
float det2_01_01 = mat[0].x * mat[1].y - mat[0].y * mat[1].x;
float det2_01_02 = mat[0].x * mat[1].z - mat[0].z * mat[1].x;
float det2_01_03 = mat[0].x * mat[1].w - mat[0].w * mat[1].x;
float det2_01_12 = mat[0].y * mat[1].z - mat[0].z * mat[1].y;
float det2_01_13 = mat[0].y * mat[1].w - mat[0].w * mat[1].y;
float det2_01_23 = mat[0].z * mat[1].w - mat[0].w * mat[1].z;
// 3x3 sub-determinants required to calculate 4x4 determinant
float det3_201_012 = mat[2].x * det2_01_12 - mat[2].y * det2_01_02 + mat[2].z * det2_01_01;
float det3_201_013 = mat[2].x * det2_01_13 - mat[2].y * det2_01_03 + mat[2].w * det2_01_01;
float det3_201_023 = mat[2].x * det2_01_23 - mat[2].z * det2_01_03 + mat[2].w * det2_01_02;
float det3_201_123 = mat[2].y * det2_01_23 - mat[2].z * det2_01_13 + mat[2].w * det2_01_12;
double det = (-det3_201_123 * mat[3].x + det3_201_023 * mat[3].y - det3_201_013 * mat[3].z + det3_201_012 * mat[3].w);
if (idMath.Fabs(det) < MATRIX_INVERSE_EPSILON)
return false;
double invDet = 1.0f / det;
// remaining 2x2 sub-determinants
float det2_03_01 = mat[0].x * mat[3].y - mat[0].y * mat[3].x;
float det2_03_02 = mat[0].x * mat[3].z - mat[0].z * mat[3].x;
float det2_03_03 = mat[0].x * mat[3].w - mat[0].w * mat[3].x;
float det2_03_12 = mat[0].y * mat[3].z - mat[0].z * mat[3].y;
float det2_03_13 = mat[0].y * mat[3].w - mat[0].w * mat[3].y;
float det2_03_23 = mat[0].z * mat[3].w - mat[0].w * mat[3].z;
//
float det2_13_01 = mat[1].x * mat[3].y - mat[1].y * mat[3].x;
float det2_13_02 = mat[1].x * mat[3].z - mat[1].z * mat[3].x;
float det2_13_03 = mat[1].x * mat[3].w - mat[1].w * mat[3].x;
float det2_13_12 = mat[1].y * mat[3].z - mat[1].z * mat[3].y;
float det2_13_13 = mat[1].y * mat[3].w - mat[1].w * mat[3].y;
float det2_13_23 = mat[1].z * mat[3].w - mat[1].w * mat[3].z;
// remaining 3x3 sub-determinants
float det3_203_012 = mat[2].x * det2_03_12 - mat[2].y * det2_03_02 + mat[2].z * det2_03_01;
float det3_203_013 = mat[2].x * det2_03_13 - mat[2].y * det2_03_03 + mat[2].w * det2_03_01;
float det3_203_023 = mat[2].x * det2_03_23 - mat[2].z * det2_03_03 + mat[2].w * det2_03_02;
float det3_203_123 = mat[2].y * det2_03_23 - mat[2].z * det2_03_13 + mat[2].w * det2_03_12;
//
float det3_213_012 = mat[2].x * det2_13_12 - mat[2].y * det2_13_02 + mat[2].z * det2_13_01;
float det3_213_013 = mat[2].x * det2_13_13 - mat[2].y * det2_13_03 + mat[2].w * det2_13_01;
float det3_213_023 = mat[2].x * det2_13_23 - mat[2].z * det2_13_03 + mat[2].w * det2_13_02;
float det3_213_123 = mat[2].y * det2_13_23 - mat[2].z * det2_13_13 + mat[2].w * det2_13_12;
//
float det3_301_012 = mat[3].x * det2_01_12 - mat[3].y * det2_01_02 + mat[3].z * det2_01_01;
float det3_301_013 = mat[3].x * det2_01_13 - mat[3].y * det2_01_03 + mat[3].w * det2_01_01;
float det3_301_023 = mat[3].x * det2_01_23 - mat[3].z * det2_01_03 + mat[3].w * det2_01_02;
float det3_301_123 = mat[3].y * det2_01_23 - mat[3].z * det2_01_13 + mat[3].w * det2_01_12;
//
mat[0].x = (float)(-det3_213_123 * invDet);
mat[1].x = (float)(+det3_213_023 * invDet);
mat[2].x = (float)(-det3_213_013 * invDet);
mat[3].x = (float)(+det3_213_012 * invDet);
//
mat[0].y = (float)(+det3_203_123 * invDet);
mat[1].y = (float)(-det3_203_023 * invDet);
mat[2].y = (float)(+det3_203_013 * invDet);
mat[3].y = (float)(-det3_203_012 * invDet);
//
mat[0].z = (float)(+det3_301_123 * invDet);
mat[1].z = (float)(-det3_301_023 * invDet);
mat[2].z = (float)(+det3_301_013 * invDet);
mat[3].z = (float)(-det3_301_012 * invDet);
//
mat[0].w = (float)(-det3_201_123 * invDet);
mat[1].w = (float)(+det3_201_023 * invDet);
mat[2].w = (float)(-det3_201_013 * invDet);
mat[3].w = (float)(+det3_201_012 * invDet);
return true;
#elif false
// 4*18 = 72 multiplications
// 4 divisions
float *mat = reinterpret_cast<float *>(this);
float s;
double d, di;
di = mat[0];
s = di;
mat[0] = d = 1.0f / di;
mat[1] *= d;
mat[2] *= d;
mat[3] *= d;
d = -d;
mat[4] *= d;
mat[8] *= d;
mat[12] *= d;
d = mat[4] * di;
mat[5] += mat[1] * d;
mat[6] += mat[2] * d;
mat[7] += mat[3] * d;
d = mat[8] * di;
mat[9] += mat[1] * d;
mat[10] += mat[2] * d;
mat[11] += mat[3] * d;
d = mat[12] * di;
mat[13] += mat[1] * d;
mat[14] += mat[2] * d;
mat[15] += mat[3] * d;
di = mat[5];
s *= di;
mat[5] = d = 1.0f / di;
mat[4] *= d;
mat[6] *= d;
mat[7] *= d;
d = -d;
mat[1] *= d;
mat[9] *= d;
mat[13] *= d;
d = mat[1] * di;
mat[0] += mat[4] * d;
mat[2] += mat[6] * d;
mat[3] += mat[7] * d;
d = mat[9] * di;
mat[8] += mat[4] * d;
mat[10] += mat[6] * d;
mat[11] += mat[7] * d;
d = mat[13] * di;
mat[12] += mat[4] * d;
mat[14] += mat[6] * d;
mat[15] += mat[7] * d;
di = mat[10];
s *= di;
mat[10] = d = 1.0f / di;
mat[8] *= d;
mat[9] *= d;
mat[11] *= d;
d = -d;
mat[2] *= d;
mat[6] *= d;
mat[14] *= d;
d = mat[2] * di;
mat[0] += mat[8] * d;
mat[1] += mat[9] * d;
mat[3] += mat[11] * d;
d = mat[6] * di;
mat[4] += mat[8] * d;
mat[5] += mat[9] * d;
mat[7] += mat[11] * d;
d = mat[14] * di;
mat[12] += mat[8] * d;
mat[13] += mat[9] * d;
mat[15] += mat[11] * d;
di = mat[15];
s *= di;
mat[15] = d = 1.0f / di;
mat[12] *= d;
mat[13] *= d;
mat[14] *= d;
d = -d;
mat[3] *= d;
mat[7] *= d;
mat[11] *= d;
d = mat[3] * di;
mat[0] += mat[12] * d;
mat[1] += mat[13] * d;
mat[2] += mat[14] * d;
d = mat[7] * di;
mat[4] += mat[12] * d;
mat[5] += mat[13] * d;
mat[6] += mat[14] * d;
d = mat[11] * di;
mat[8] += mat[12] * d;
mat[9] += mat[13] * d;
mat[10] += mat[14] * d;
return ( s != 0.0f && !FLOAT_IS_NAN( s ) );
#else
// 6*8+2*6 = 60 multiplications
// 2*1 = 2 divisions
float[] mat = this;
// r0 = m0.Inverse();
float det = mat[0 * 4 + 0] * mat[1 * 4 + 1] - mat[0 * 4 + 1] * mat[1 * 4 + 0];
if (idMath.Fabs(det) < MATRIX_INVERSE_EPSILON)
return false;
float invDet = 1.0f / det;
idMat2 r0 = new idMat2(); idVec2[] r0_mat = r0.mat;
r0_mat[0].x = mat[1 * 4 + 1] * invDet;
r0_mat[0].y = -mat[0 * 4 + 1] * invDet;
r0_mat[1].x = -mat[1 * 4 + 0] * invDet;
r0_mat[1].y = mat[0 * 4 + 0] * invDet;
// r1 = r0 * m1;
idMat2 r1 = new idMat2(); idVec2[] r1_mat = r1.mat;
r1_mat[0].x = r0_mat[0].x * mat[0 * 4 + 2] + r0_mat[0].y * mat[1 * 4 + 2];
r1_mat[0].y = r0_mat[0].x * mat[0 * 4 + 3] + r0_mat[0].y * mat[1 * 4 + 3];
r1_mat[1].x = r0_mat[1].x * mat[0 * 4 + 2] + r0_mat[1].y * mat[1 * 4 + 2];
r1_mat[1].y = r0_mat[1].x * mat[0 * 4 + 3] + r0_mat[1].y * mat[1 * 4 + 3];
// r2 = m2 * r1;
idMat2 r2 = new idMat2(); idVec2[] r2_mat = r2.mat;
r2_mat[0].x = mat[2 * 4 + 0] * r1_mat[0].x + mat[2 * 4 + 1] * r1_mat[1].x;
r2_mat[0].y = mat[2 * 4 + 0] * r1_mat[0].y + mat[2 * 4 + 1] * r1_mat[1].y;
r2_mat[1].x = mat[3 * 4 + 0] * r1_mat[0].x + mat[3 * 4 + 1] * r1_mat[1].x;
r2_mat[1].y = mat[3 * 4 + 0] * r1_mat[0].y + mat[3 * 4 + 1] * r1_mat[1].y;
// r3 = r2 - m3;
idMat2 r3 = new idMat2(); idVec2[] r3_mat = r3.mat;
r3_mat[0].x = r2_mat[0].x - mat[2 * 4 + 2];
r3_mat[0].y = r2_mat[0].y - mat[2 * 4 + 3];
r3_mat[1].x = r2_mat[1].x - mat[3 * 4 + 2];
r3_mat[1].y = r2_mat[1].y - mat[3 * 4 + 3];
// r3.InverseSelf();
det = r3_mat[0].x * r3_mat[1].y - r3_mat[0].y * r3_mat[1].x;
if (idMath.Fabs(det) < MATRIX_INVERSE_EPSILON)
return false;
invDet = 1.0f / det;
float a = r3_mat[0].x;
r3_mat[0].x = r3_mat[1].y * invDet;
r3_mat[0].y = -r3_mat[0].y * invDet;
r3_mat[1].x = -r3_mat[1].x * invDet;
r3_mat[1].y = a * invDet;
// r2 = m2 * r0;
r2_mat[0].x = mat[2 * 4 + 0] * r0_mat[0].x + mat[2 * 4 + 1] * r0_mat[1].x;
r2_mat[0].y = mat[2 * 4 + 0] * r0_mat[0].y + mat[2 * 4 + 1] * r0_mat[1].y;
r2_mat[1].x = mat[3 * 4 + 0] * r0_mat[0].x + mat[3 * 4 + 1] * r0_mat[1].x;
r2_mat[1].y = mat[3 * 4 + 0] * r0_mat[0].y + mat[3 * 4 + 1] * r0_mat[1].y;
// m2 = r3 * r2;
mat[2 * 4 + 0] = r3_mat[0].x * r2_mat[0].x + r3_mat[0].y * r2_mat[1].x;
mat[2 * 4 + 1] = r3_mat[0].x * r2_mat[0].y + r3_mat[0].y * r2_mat[1].y;
mat[3 * 4 + 0] = r3_mat[1].x * r2_mat[0].x + r3_mat[1].y * r2_mat[1].x;
mat[3 * 4 + 1] = r3_mat[1].x * r2_mat[0].y + r3_mat[1].y * r2_mat[1].y;
// m0 = r0 - r1 * m2;
mat[0 * 4 + 0] = r0_mat[0].x - r1_mat[0].x * mat[2 * 4 + 0] - r1_mat[0].y * mat[3 * 4 + 0];
mat[0 * 4 + 1] = r0_mat[0].y - r1_mat[0].x * mat[2 * 4 + 1] - r1_mat[0].y * mat[3 * 4 + 1];
mat[1 * 4 + 0] = r0_mat[1].x - r1_mat[1].x * mat[2 * 4 + 0] - r1_mat[1].y * mat[3 * 4 + 0];
mat[1 * 4 + 1] = r0_mat[1].y - r1_mat[1].x * mat[2 * 4 + 1] - r1_mat[1].y * mat[3 * 4 + 1];
// m1 = r1 * r3;
mat[0 * 4 + 2] = r1_mat[0].x * r3_mat[0].x + r1_mat[0].x * r3_mat[1].x;
mat[0 * 4 + 3] = r1_mat[0].x * r3_mat[0].y + r1_mat[0].x * r3_mat[1].y;
mat[1 * 4 + 2] = r1_mat[1].x * r3_mat[0].x + r1_mat[1].x * r3_mat[1].x;
mat[1 * 4 + 3] = r1_mat[1].x * r3_mat[0].y + r1_mat[1].x * r3_mat[1].y;
// m3 = -r3;
mat[2 * 4 + 2] = -r3_mat[0].x;
mat[2 * 4 + 3] = -r3_mat[0].y;
mat[3 * 4 + 2] = -r3_mat[1].x;
mat[3 * 4 + 3] = -r3_mat[1].y;
return true;
#endif
}
