/* Add BSDF data point */
void
add_bsdf_data(double theta_out, double phi_out, double val, int isDSF)
{
FVECT ovec;
int pos[2];
if (!output_orient) /* check output orientation */
output_orient = 1 - 2*(theta_out > 90.);
else if (output_orient > 0 ^ theta_out < 90.) {
fputs("Cannot handle output angles on both sides of surface\n",
stderr);
exit(1);
}
ovec[2] = sin((M_PI/180.)*theta_out);
ovec[0] = cos((M_PI/180.)*phi_out) * ovec[2];
ovec[1] = sin((M_PI/180.)*phi_out) * ovec[2];
ovec[2] = sqrt(1. - ovec[2]*ovec[2]);
if (!isDSF)
val *= ovec[2]; /* convert from BSDF to DSF */
/* update BSDF histogram */
if (val < BSDF2BIG*ovec[2] && val > BSDF2SML*ovec[2])
++bsdf_hist[histndx(val/ovec[2])];
pos_from_vec(pos, ovec);
dsf_grid[pos[0]][pos[1]].vsum += val;
dsf_grid[pos[0]][pos[1]].nval++;
}
/* Rotate RBF to correspond to given incident vector */
void
rotate_rbf(RBFNODE *rbf, const FVECT invec)
{
static const FVECT vnorm = {.0, .0, 1.};
const double phi = atan2(invec[1],invec[0]) -
atan2(rbf->invec[1],rbf->invec[0]);
FVECT outvec;
int pos[2];
int n;
for (n = ((-.01 > phi) | (phi > .01))*rbf->nrbf; n-- > 0; ) {
ovec_from_pos(outvec, rbf->rbfa[n].gx, rbf->rbfa[n].gy);
spinvector(outvec, outvec, vnorm, phi);
pos_from_vec(pos, outvec);
rbf->rbfa[n].gx = pos[0];
rbf->rbfa[n].gy = pos[1];
}
VCOPY(rbf->invec, invec);
}
