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-rw-r--r--src/glu/sgi/libutil/project.c115
1 files changed, 49 insertions, 66 deletions
diff --git a/src/glu/sgi/libutil/project.c b/src/glu/sgi/libutil/project.c
index 2b20ad4fb3..d22989c385 100644
--- a/src/glu/sgi/libutil/project.c
+++ b/src/glu/sgi/libutil/project.c
@@ -168,74 +168,57 @@ static void __gluMultMatrixVecd(const GLdouble matrix[16], const GLdouble in[4],
}
/*
-** inverse = invert(src)
-** New, faster implementation by Shan Hao Bo, April 2006.
+** Invert 4x4 matrix.
+** Contributed by David Moore (See Mesa bug #6748)
*/
-static int __gluInvertMatrixd(const GLdouble src[16], GLdouble inverse[16])
+static int __gluInvertMatrixd(const GLdouble m[16], GLdouble inv[16])
{
- int i, j, k;
- double t;
- GLdouble temp[4][4];
-
- for (i=0; i<4; i++) {
- for (j=0; j<4; j++) {
- temp[i][j] = src[i*4+j];
- }
- }
- __gluMakeIdentityd(inverse);
-
- for (i = 0; i < 4; i++) {
- if (temp[i][i] == 0.0f) {
- /*
- ** Look for non-zero element in column
- */
- for (j = i + 1; j < 4; j++) {
- if (temp[j][i] != 0.0f) {
- break;
- }
- }
-
- if (j != 4) {
- /*
- ** Swap rows.
- */
- for (k = 0; k < 4; k++) {
- t = temp[i][k];
- temp[i][k] = temp[j][k];
- temp[j][k] = t;
-
- t = inverse[i*4+k];
- inverse[i*4+k] = inverse[j*4+k];
- inverse[j*4+k] = t;
- }
- }
- else {
- /*
- ** No non-zero pivot. The matrix is singular,
-which shouldn't
- ** happen. This means the user gave us a bad
-matrix.
- */
- return GL_FALSE;
- }
- }
-
- t = 1.0f / temp[i][i];
- for (k = 0; k < 4; k++) {
- temp[i][k] *= t;
- inverse[i*4+k] *= t;
- }
- for (j = 0; j < 4; j++) {
- if (j != i) {
- t = temp[j][i];
- for (k = 0; k < 4; k++) {
- temp[j][k] -= temp[i][k]*t;
- inverse[j*4+k] -= inverse[i*4+k]*t;
- }
- }
- }
- }
- return GL_TRUE;
+ double det;
+ int i;
+
+ inv[0] = m[5]*m[10]*m[15] - m[5]*m[11]*m[14] - m[9]*m[6]*m[15]
+ + m[9]*m[7]*m[14] + m[13]*m[6]*m[11] - m[13]*m[7]*m[10];
+ inv[4] = -m[4]*m[10]*m[15] + m[4]*m[11]*m[14] + m[8]*m[6]*m[15]
+ - m[8]*m[7]*m[14] - m[12]*m[6]*m[11] + m[12]*m[7]*m[10];
+ inv[8] = m[4]*m[9]*m[15] - m[4]*m[11]*m[13] - m[8]*m[5]*m[15]
+ + m[8]*m[7]*m[13] + m[12]*m[5]*m[11] - m[12]*m[7]*m[9];
+ inv[12] = -m[4]*m[9]*m[14] + m[4]*m[10]*m[13] + m[8]*m[5]*m[14]
+ - m[8]*m[6]*m[13] - m[12]*m[5]*m[10] + m[12]*m[6]*m[9];
+ inv[1] = -m[1]*m[10]*m[15] + m[1]*m[11]*m[14] + m[9]*m[2]*m[15]
+ - m[9]*m[3]*m[14] - m[13]*m[2]*m[11] + m[13]*m[3]*m[10];
+ inv[5] = m[0]*m[10]*m[15] - m[0]*m[11]*m[14] - m[8]*m[2]*m[15]
+ + m[8]*m[3]*m[14] + m[12]*m[2]*m[11] - m[12]*m[3]*m[10];
+ inv[9] = -m[0]*m[9]*m[15] + m[0]*m[11]*m[13] + m[8]*m[1]*m[15]
+ - m[8]*m[3]*m[13] - m[12]*m[1]*m[11] + m[12]*m[3]*m[9];
+ inv[13] = m[0]*m[9]*m[14] - m[0]*m[10]*m[13] - m[8]*m[1]*m[14]
+ + m[8]*m[2]*m[13] + m[12]*m[1]*m[10] - m[12]*m[2]*m[9];
+ inv[2] = m[1]*m[6]*m[15] - m[1]*m[7]*m[14] - m[5]*m[2]*m[15]
+ + m[5]*m[3]*m[14] + m[13]*m[2]*m[7] - m[13]*m[3]*m[6];
+ inv[6] = -m[0]*m[6]*m[15] + m[0]*m[7]*m[14] + m[4]*m[2]*m[15]
+ - m[4]*m[3]*m[14] - m[12]*m[2]*m[7] + m[12]*m[3]*m[6];
+ inv[10] = m[0]*m[5]*m[15] - m[0]*m[7]*m[13] - m[4]*m[1]*m[15]
+ + m[4]*m[3]*m[13] + m[12]*m[1]*m[7] - m[12]*m[3]*m[5];
+ inv[14] = -m[0]*m[5]*m[14] + m[0]*m[6]*m[13] + m[4]*m[1]*m[14]
+ - m[4]*m[2]*m[13] - m[12]*m[1]*m[6] + m[12]*m[2]*m[5];
+ inv[3] = -m[1]*m[6]*m[11] + m[1]*m[7]*m[10] + m[5]*m[2]*m[11]
+ - m[5]*m[3]*m[10] - m[9]*m[2]*m[7] + m[9]*m[3]*m[6];
+ inv[7] = m[0]*m[6]*m[11] - m[0]*m[7]*m[10] - m[4]*m[2]*m[11]
+ + m[4]*m[3]*m[10] + m[8]*m[2]*m[7] - m[8]*m[3]*m[6];
+ inv[11] = -m[0]*m[5]*m[11] + m[0]*m[7]*m[9] + m[4]*m[1]*m[11]
+ - m[4]*m[3]*m[9] - m[8]*m[1]*m[7] + m[8]*m[3]*m[5];
+ inv[15] = m[0]*m[5]*m[10] - m[0]*m[6]*m[9] - m[4]*m[1]*m[10]
+ + m[4]*m[2]*m[9] + m[8]*m[1]*m[6] - m[8]*m[2]*m[5];
+
+ det = m[0]*inv[0] + m[1]*inv[4] + m[2]*inv[8] + m[3]*inv[12];
+ if (det == 0)
+ return GL_FALSE;
+
+ det = 1.0 / det;
+
+ for (i = 0; i < 16; i++)
+ inv[i] *= det;
+
+ return GL_TRUE;
}
static void __gluMultMatricesd(const GLdouble a[16], const GLdouble b[16],