144    float *r0, *r1, *r2, *r3;  in util_invert_mat4x4()  local
154    r0 = wtmp[0], r1 = wtmp[1], r2 = wtmp[2], r3 = wtmp[3];  in util_invert_mat4x4()
159    r1[0] = MAT(m, 1, 0), r1[1] = MAT(m, 1, 1), r1[2] = MAT(m, 1, 2), r1[3] = MAT(m, 1, 3),  in util_invert_mat4x4()
160    r1[5] = 1.0, r1[4] = r1[6] = r1[7] = 0.0,  in util_invert_mat4x4()
171    if (fabsf(r2[0]) > fabsf(r1[0]))  in util_invert_mat4x4()
172       SWAP_ROWS(r2, r1);  in util_invert_mat4x4()
173    if (fabsf(r1[0]) > fabsf(r0[0]))  in util_invert_mat4x4()
174       SWAP_ROWS(r1, r0);  in util_invert_mat4x4()
179    m1 = r1[0] / r0[0];  in util_invert_mat4x4()
183    r1[1] -= m1 * s;  in util_invert_mat4x4()
187    r1[2] -= m1 * s;  in util_invert_mat4x4()
191    r1[3] -= m1 * s;  in util_invert_mat4x4()
196       r1[4] -= m1 * s;  in util_invert_mat4x4()
202       r1[5] -= m1 * s;  in util_invert_mat4x4()
208       r1[6] -= m1 * s;  in util_invert_mat4x4()
214       r1[7] -= m1 * s;  in util_invert_mat4x4()
222    if (fabsf(r2[1]) > fabsf(r1[1]))  in util_invert_mat4x4()
223       SWAP_ROWS(r2, r1);  in util_invert_mat4x4()
224    if (0.0F == r1[1])  in util_invert_mat4x4()
228    m2 = r2[1] / r1[1];  in util_invert_mat4x4()
229    m3 = r3[1] / r1[1];  in util_invert_mat4x4()
230    r2[2] -= m2 * r1[2];  in util_invert_mat4x4()
231    r3[2] -= m3 * r1[2];  in util_invert_mat4x4()
232    r2[3] -= m2 * r1[3];  in util_invert_mat4x4()
233    r3[3] -= m3 * r1[3];  in util_invert_mat4x4()
234    s = r1[4];  in util_invert_mat4x4()
239    s = r1[5];  in util_invert_mat4x4()
244    s = r1[6];  in util_invert_mat4x4()
249    s = r1[7];  in util_invert_mat4x4()
280    m1 = r1[3];  in util_invert_mat4x4()
281    r1[4] -= r3[4] * m1, r1[5] -= r3[5] * m1, r1[6] -= r3[6] * m1, r1[7] -= r3[7] * m1;  in util_invert_mat4x4()
285    m1 = r1[2]; /* now back substitute row 1 */  in util_invert_mat4x4()
286    s = 1.0F / r1[1];  in util_invert_mat4x4()
287    r1[4] = s * (r1[4] - r2[4] * m1), r1[5] = s * (r1[5] - r2[5] * m1),  in util_invert_mat4x4()
288    r1[6] = s * (r1[6] - r2[6] * m1), r1[7] = s * (r1[7] - r2[7] * m1);  in util_invert_mat4x4()
294    r0[4] = s * (r0[4] - r1[4] * m0), r0[5] = s * (r0[5] - r1[5] * m0),  in util_invert_mat4x4()
295    r0[6] = s * (r0[6] - r1[6] * m0), r0[7] = s * (r0[7] - r1[7] * m0);  in util_invert_mat4x4()
299    MAT(out, 0, 3) = r0[7], MAT(out, 1, 0) = r1[4];  in util_invert_mat4x4()
300    MAT(out, 1, 1) = r1[5], MAT(out, 1, 2) = r1[6];  in util_invert_mat4x4()
301    MAT(out, 1, 3) = r1[7], MAT(out, 2, 0) = r2[4];  in util_invert_mat4x4()