Wtransf
compute_xf(CARRAY<Wvec>& v)
{
WMat3 A;
// build the symmetric matrix:
double s = 0;
for (int i=0; i<3; i++) {
for (int j=i; j<3; j++) {
A[i][j] = A[j][i] = cross_mult(i,j,v);
s = max(s, fabs(A[i][j]));
}
}
// divide by largest value:
if (s > 1e-5)
A = A/s;
cerr << "A: "
<< endl
<< A
<< endl;
WMat3 V = sym_mat_eigenvectors(A);
// this just handles the rotation...
return Wtransf(V.row(0),V.row(1),V.row(2)).transpose();
}
void
SKY_BOX::update_position() //centers the sky box around the camera
{
Wpt eye = VIEW::eye();
if (eye.dist_sqrd(xform().origin()) > 0) { //only update when really needed
set_xform(Wtransf(eye));
err_adv(debug, "SKY_BOX::update_position: updated skybox");
}
}
