src/cv/bsdfrep.c

#ifndef lint
static const char RCSid[] = "$Id: bsdfrep.c,v 2.34 2020/10/26 21:12:20 greg Exp $";
#endif
/*
 * Support BSDF representation as radial basis functions.
 *
 *      G. Ward
 */

#define _USE_MATH_DEFINES
#include <stdlib.h>
#include <math.h>
#include "rtio.h"
#include "resolu.h"
#include "bsdfrep.h"
#include "random.h"
                                /* name and manufacturer if known */
char                    bsdf_name[256];
char                    bsdf_manuf[256];
                                /* active grid resolution */
int                     grid_res = GRIDRES;

                                /* coverage/symmetry using INP_QUAD? flags */
int                     inp_coverage = 0;
                                /* all incident angles in-plane so far? */
int                     single_plane_incident = -1;

                                /* input/output orientations */
int                     input_orient = 0;
int                     output_orient = 0;

                                /* represented color space */
RBColor                 rbf_colorimetry = RBCunknown;

const char              *RBCident[] = {
                                "CIE-Y", "CIE-XYZ", "Spectral", "Unknown"
                        };

                                /* BSDF histogram */
unsigned long           bsdf_hist[HISTLEN];

                                /* BSDF value for boundary regions */
double                  bsdf_min = 0;
double                  bsdf_spec_val = 0;
double                  bsdf_spec_rad = 0;

                                /* processed incident DSF measurements */
RBFNODE                 *dsf_list = NULL;

                                /* RBF-linking matrices (edges) */
MIGRATION               *mig_list = NULL;

                                /* current input direction */
double                  theta_in_deg, phi_in_deg;

                                /* header line sharing callback */
int                     (*sir_headshare)(char *s) = NULL;

/* Register new input direction */
int
new_input_direction(double new_theta, double new_phi)
{
                                        /* normalize angle ranges */
        while (new_theta < -180.)
                new_theta += 360.;
        while (new_theta > 180.)
                new_theta -= 360.;
        if (new_theta < 0) {
                new_theta = -new_theta;
                new_phi += 180.;
        }
        while (new_phi < 0)
                new_phi += 360.;
        while (new_phi >= 360.)
                new_phi -= 360.;
                                        /* check input orientation */
        if (!input_orient)
                input_orient = 1 - 2*(new_theta > 90.);
        else if (input_orient > 0 ^ new_theta < 90.) {
                fprintf(stderr,
                "%s: Cannot handle input angles on both sides of surface\n",
                                progname);
                return(0);
        }
        if ((theta_in_deg = new_theta) < 1.0)
                return(1);              /* don't rely on phi near normal */
        if (single_plane_incident > 0)  /* check input coverage */
                single_plane_incident = (round(new_phi) == round(phi_in_deg));
        else if (single_plane_incident < 0)
                single_plane_incident = 1;
        phi_in_deg = new_phi;
        if ((1. < new_phi) & (new_phi < 89.))
                inp_coverage |= INP_QUAD1;
        else if ((91. < new_phi) & (new_phi < 179.))
                inp_coverage |= INP_QUAD2;
        else if ((181. < new_phi) & (new_phi < 269.))
                inp_coverage |= INP_QUAD3;
        else if ((271. < new_phi) & (new_phi < 359.))
                inp_coverage |= INP_QUAD4;
        return(1);
}

/* Apply symmetry to the given vector based on distribution */
int
use_symmetry(FVECT vec)
{
        const double    phi = get_phi360(vec);

        switch (inp_coverage) {
        case INP_QUAD1|INP_QUAD2|INP_QUAD3|INP_QUAD4:
                break;
        case INP_QUAD1|INP_QUAD2:
                if ((-FTINY > phi) | (phi > 180.+FTINY))
                        goto mir_y;
                break;
        case INP_QUAD2|INP_QUAD3:
                if ((90.-FTINY > phi) | (phi > 270.+FTINY))
                        goto mir_x;
                break;
        case INP_QUAD3|INP_QUAD4:
                if ((180.-FTINY > phi) | (phi > 360.+FTINY))
                        goto mir_y;
                break;
        case INP_QUAD4|INP_QUAD1:
                if ((270.-FTINY > phi) & (phi > 90.+FTINY))
                        goto mir_x;
                break;
        case INP_QUAD1:
                if ((-FTINY > phi) | (phi > 90.+FTINY))
                        switch ((int)(phi*(1./90.))) {
                        case 1: goto mir_x;
                        case 2: goto mir_xy;
                        case 3: goto mir_y;
                        }
                break;
        case INP_QUAD2:
                if ((90.-FTINY > phi) | (phi > 180.+FTINY))
                        switch ((int)(phi*(1./90.))) {
                        case 0: goto mir_x;
                        case 2: goto mir_y;
                        case 3: goto mir_xy;
                        }
                break;
        case INP_QUAD3:
                if ((180.-FTINY > phi) | (phi > 270.+FTINY))
                        switch ((int)(phi*(1./90.))) {
                        case 0: goto mir_xy;
                        case 1: goto mir_y;
                        case 3: goto mir_x;
                        }
                break;
        case INP_QUAD4:
                if ((270.-FTINY > phi) | (phi > 360.+FTINY))
                        switch ((int)(phi*(1./90.))) {
                        case 0: goto mir_y;
                        case 1: goto mir_xy;
                        case 2: goto mir_x;
                        }
                break;
        default:
                fprintf(stderr, "%s: Illegal input coverage (%d)\n",
                                        progname, inp_coverage);
                exit(1);
        }
        return(0);              /* in range */
mir_x:
        vec[0] = -vec[0];
        return(MIRROR_X);
mir_y:
        vec[1] = -vec[1];
        return(MIRROR_Y);
mir_xy:
        vec[0] = -vec[0];
        vec[1] = -vec[1];
        return(MIRROR_X|MIRROR_Y);
}

/* Reverse symmetry based on what was done before */
void
rev_symmetry(FVECT vec, int sym)
{
        if (sym & MIRROR_X)
                vec[0] = -vec[0];
        if (sym & MIRROR_Y)
                vec[1] = -vec[1];
}

/* Reverse symmetry for an RBF distribution */
void
rev_rbf_symmetry(RBFNODE *rbf, int sym)
{
        int     n;

        rev_symmetry(rbf->invec, sym);
        if (sym & MIRROR_X)
                for (n = rbf->nrbf; n-- > 0; )
                        rbf->rbfa[n].gx = grid_res-1 - rbf->rbfa[n].gx;
        if (sym & MIRROR_Y)
                for (n = rbf->nrbf; n-- > 0; )
                        rbf->rbfa[n].gy = grid_res-1 - rbf->rbfa[n].gy;
}

/* 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 = (cos(phi) < 1.-FTINY)*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);
}

/* Compute outgoing vector from grid position */
void
ovec_from_pos(FVECT vec, int xpos, int ypos)
{
        double  uv[2];
        double  r2;
        
        SDsquare2disk(uv, (xpos+.5)/grid_res, (ypos+.5)/grid_res);
                                /* uniform hemispherical projection */
        r2 = uv[0]*uv[0] + uv[1]*uv[1];
        vec[0] = vec[1] = sqrt(2. - r2);
        vec[0] *= uv[0];
        vec[1] *= uv[1];
        vec[2] = output_orient*(1. - r2);
}

/* Compute grid position from normalized input/output vector */
void
pos_from_vec(int pos[2], const FVECT vec)
{
        double  sq[2];          /* uniform hemispherical projection */
        double  norm = 1./sqrt(1. + fabs(vec[2]));

        SDdisk2square(sq, vec[0]*norm, vec[1]*norm);

        pos[0] = (int)(sq[0]*grid_res);
        pos[1] = (int)(sq[1]*grid_res);
}

/* Compute volume associated with Gaussian lobe */
double
rbf_volume(const RBFVAL *rbfp)
{
        double  rad = R2ANG(rbfp->crad);
        FVECT   odir;
        double  elev, integ;
                                /* infinite integral approximation */
        integ = (2.*M_PI) * rbfp->peak * rad*rad;
                                /* check if we're near horizon */
        ovec_from_pos(odir, rbfp->gx, rbfp->gy);
        elev = output_orient*odir[2];
                                /* apply cut-off correction if > 1% */
        if (elev < 2.8*rad) {
                /* elev = asin(elev);   /* this is so crude, anyway... */
                integ *= 1. - .5*exp(-.5*elev*elev/(rad*rad));
        }
        return(integ);
}

/* Evaluate BSDF at the given normalized outgoing direction in color */
SDError
eval_rbfcol(SDValue *sv, const RBFNODE *rp, const FVECT outvec)
{
        const double    rfact2 = (38./M_PI/M_PI)*(grid_res*grid_res);
        int             pos[2];
        double          res = 0;
        double          usum = 0, vsum = 0;
        const RBFVAL    *rbfp;
        FVECT           odir;
        double          rad2;
        int             n;
                                /* assign default value */
        sv->spec = c_dfcolor;
        sv->cieY = bsdf_min;
                                /* check for wrong side */
        if (outvec[2] > 0 ^ output_orient > 0) {
                strcpy(SDerrorDetail, "Wrong-side scattering query");
                return(SDEargument);
        }
        if (rp == NULL)         /* return minimum if no information avail. */
                return(SDEnone);
                                /* optimization for fast lobe culling */
        pos_from_vec(pos, outvec);
                                /* sum radial basis function */
        rbfp = rp->rbfa;
        for (n = rp->nrbf; n--; rbfp++) {
                int     d2 = (pos[0]-rbfp->gx)*(pos[0]-rbfp->gx) +
                                (pos[1]-rbfp->gy)*(pos[1]-rbfp->gy);
                double  val;
                rad2 = R2ANG(rbfp->crad);
                rad2 *= rad2;
                if (d2 > rad2*rfact2)
                        continue;
                ovec_from_pos(odir, rbfp->gx, rbfp->gy);
                val = rbfp->peak * exp((DOT(odir,outvec) - 1.) / rad2);
                if (rbf_colorimetry == RBCtristimulus) {
                        usum += val * (rbfp->chroma & 0xff);
                        vsum += val * (rbfp->chroma>>8 & 0xff);
                }
                res += val;
        }
        sv->cieY = res / COSF(outvec[2]);
        if (sv->cieY < bsdf_min) {      /* never return less than bsdf_min */
                sv->cieY = bsdf_min;
        } else if (rbf_colorimetry == RBCtristimulus) {
                C_CHROMA        cres = (int)(usum/res + frandom());
                cres |= (int)(vsum/res + frandom()) << 8;
                c_decodeChroma(&sv->spec, cres);
        }
        return(SDEnone);
}

/* Evaluate BSDF at the given normalized outgoing direction in Y */
double
eval_rbfrep(const RBFNODE *rp, const FVECT outvec)
{
        SDValue sv;

        if (eval_rbfcol(&sv, rp, outvec) == SDEnone)
                return(sv.cieY);

        return(0.0);
}

/* Insert a new directional scattering function in our global list */
int
insert_dsf(RBFNODE *newrbf)
{
        RBFNODE         *rbf, *rbf_last;
        int             pos;
                                        /* check for redundant meas. */
        for (rbf = dsf_list; rbf != NULL; rbf = rbf->next)
                if (DOT(rbf->invec, newrbf->invec) >= 1.-FTINY) {
                        fprintf(stderr,
                "%s: Duplicate incident measurement ignored at (%.1f,%.1f)\n",
                                        progname, get_theta180(newrbf->invec),
                                        get_phi360(newrbf->invec));
                        free(newrbf);
                        return(-1);
                }
                                        /* keep in ascending theta order */
        for (rbf_last = NULL, rbf = dsf_list; rbf != NULL;
                                        rbf_last = rbf, rbf = rbf->next)
                if (single_plane_incident && input_orient*rbf->invec[2] <
                                                input_orient*newrbf->invec[2])
                        break;
        if (rbf_last == NULL) {         /* insert new node in list */
                newrbf->ord = 0;
                newrbf->next = dsf_list;
                dsf_list = newrbf;
        } else {
                newrbf->ord = rbf_last->ord + 1;
                newrbf->next = rbf;
                rbf_last->next = newrbf;
        }
        rbf_last = newrbf;
        while (rbf != NULL) {           /* update ordinal positions */
                rbf->ord = rbf_last->ord + 1;
                rbf_last = rbf;
                rbf = rbf->next;
        }
        return(newrbf->ord);
}

/* Get the DSF indicated by its ordinal position */
RBFNODE *
get_dsf(int ord)
{
        RBFNODE         *rbf;

        for (rbf = dsf_list; rbf != NULL; rbf = rbf->next)
                if (rbf->ord == ord)
                        return(rbf);
        return(NULL);
}

/* Get triangle surface orientation (unnormalized) */
void
tri_orient(FVECT vres, const FVECT v1, const FVECT v2, const FVECT v3)
{
        FVECT   v2minus1, v3minus2;

        VSUB(v2minus1, v2, v1);
        VSUB(v3minus2, v3, v2);
        VCROSS(vres, v2minus1, v3minus2);
}

/* Determine if vertex order is reversed (inward normal) */
int
is_rev_tri(const FVECT v1, const FVECT v2, const FVECT v3)
{
        FVECT   tor;

        tri_orient(tor, v1, v2, v3);

        return(DOT(tor, v2) < 0.);
}

/* Find vertices completing triangles on either side of the given edge */
int
get_triangles(RBFNODE *rbfv[2], const MIGRATION *mig)
{
        const MIGRATION *ej1, *ej2;
        RBFNODE         *tv;

        rbfv[0] = rbfv[1] = NULL;
        if (mig == NULL)
                return(0);
        for (ej1 = mig->rbfv[0]->ejl; ej1 != NULL;
                                ej1 = nextedge(mig->rbfv[0],ej1)) {
                if (ej1 == mig)
                        continue;
                tv = opp_rbf(mig->rbfv[0],ej1);
                for (ej2 = tv->ejl; ej2 != NULL; ej2 = nextedge(tv,ej2))
                        if (opp_rbf(tv,ej2) == mig->rbfv[1]) {
                                rbfv[is_rev_tri(mig->rbfv[0]->invec,
                                                mig->rbfv[1]->invec,
                                                tv->invec)] = tv;
                                break;
                        }
        }
        return((rbfv[0] != NULL) + (rbfv[1] != NULL));
}

/* Return single-lobe specular RBF for the given incident direction */
RBFNODE *
def_rbf_spec(const FVECT invec)
{
        RBFNODE         *rbf;
        FVECT           ovec;
        int             pos[2];

        if (input_orient > 0 ^ invec[2] > 0)    /* wrong side? */
                return(NULL);
        if ((bsdf_spec_val <= bsdf_min) | (bsdf_spec_rad <= 0))
                return(NULL);                   /* nothing set */
        rbf = (RBFNODE *)malloc(sizeof(RBFNODE));
        if (rbf == NULL)
                return(NULL);
        ovec[0] = -invec[0];
        ovec[1] = -invec[1];
        ovec[2] = invec[2]*(2*(input_orient==output_orient) - 1);
        pos_from_vec(pos, ovec);
        rbf->ord = 0;
        rbf->next = NULL;
        rbf->ejl = NULL;
        VCOPY(rbf->invec, invec);
        rbf->nrbf = 1;
        rbf->rbfa[0].peak = bsdf_spec_val * COSF(ovec[2]);
        rbf->rbfa[0].chroma = c_dfchroma;
        rbf->rbfa[0].crad = ANG2R(bsdf_spec_rad);
        rbf->rbfa[0].gx = pos[0];
        rbf->rbfa[0].gy = pos[1];
        rbf->vtotal = rbf_volume(rbf->rbfa);
        return(rbf);
}

/* Advect and allocate new RBF along edge (internal call) */
RBFNODE *
e_advect_rbf(const MIGRATION *mig, const FVECT invec, int lobe_lim)
{
        double          cthresh = FTINY;
        RBFNODE         *rbf;
        int             n, i, j;
        double          t, full_dist;
                                                /* get relative position */
        t = Acos(DOT(invec, mig->rbfv[0]->invec));
        if (t <= .001) {                        /* near first DSF */
                n = sizeof(RBFNODE) + sizeof(RBFVAL)*(mig->rbfv[0]->nrbf-1);
                rbf = (RBFNODE *)malloc(n);
                if (rbf == NULL)
                        goto memerr;
                memcpy(rbf, mig->rbfv[0], n);   /* just duplicate */
                rbf->next = NULL; rbf->ejl = NULL;
                return(rbf);
        }
        full_dist = acos(DOT(mig->rbfv[0]->invec, mig->rbfv[1]->invec));
        if (t >= full_dist-.001) {              /* near second DSF */
                n = sizeof(RBFNODE) + sizeof(RBFVAL)*(mig->rbfv[1]->nrbf-1);
                rbf = (RBFNODE *)malloc(n);
                if (rbf == NULL)
                        goto memerr;
                memcpy(rbf, mig->rbfv[1], n);   /* just duplicate */
                rbf->next = NULL; rbf->ejl = NULL;
                return(rbf);
        }
        t /= full_dist;
tryagain:
        n = 0;                                  /* count migrating particles */
        for (i = 0; i < mtx_nrows(mig); i++)
            for (j = 0; j < mtx_ncols(mig); j++)
                n += (mtx_coef(mig,i,j) > cthresh);
                                                /* are we over our limit? */
        if ((lobe_lim > 0) & (n > lobe_lim)) {
                cthresh = cthresh*2. + 10.*FTINY;
                goto tryagain;
        }
#ifdef DEBUG
        fprintf(stderr, "Input RBFs have %d, %d nodes -> output has %d\n",
                        mig->rbfv[0]->nrbf, mig->rbfv[1]->nrbf, n);
#endif
        rbf = (RBFNODE *)malloc(sizeof(RBFNODE) + sizeof(RBFVAL)*(n-1));
        if (rbf == NULL)
                goto memerr;
        rbf->next = NULL; rbf->ejl = NULL;
        VCOPY(rbf->invec, invec);
        rbf->nrbf = n;
        rbf->vtotal = 1.-t + t*mig->rbfv[1]->vtotal/mig->rbfv[0]->vtotal;
        n = 0;                                  /* advect RBF lobes */
        for (i = 0; i < mtx_nrows(mig); i++) {
            const RBFVAL        *rbf0i = &mig->rbfv[0]->rbfa[i];
            const float         peak0 = rbf0i->peak;
            const double        rad0 = R2ANG(rbf0i->crad);
            C_COLOR             cc0;
            FVECT               v0;
            float               mv;
            ovec_from_pos(v0, rbf0i->gx, rbf0i->gy);
            c_decodeChroma(&cc0, rbf0i->chroma);
            for (j = 0; j < mtx_ncols(mig); j++)
                if ((mv = mtx_coef(mig,i,j)) > cthresh) {
                        const RBFVAL    *rbf1j = &mig->rbfv[1]->rbfa[j];
                        double          rad2;
                        FVECT           v;
                        int             pos[2];
                        rad2 = R2ANG(rbf1j->crad);
                        rad2 = rad0*rad0*(1.-t) + rad2*rad2*t;
                        rbf->rbfa[n].peak = peak0 * mv * rbf->vtotal *
                                                rad0*rad0/rad2;
                        if (rbf_colorimetry == RBCtristimulus) {
                                C_COLOR cres;
                                c_decodeChroma(&cres, rbf1j->chroma);
                                c_cmix(&cres, 1.-t, &cc0, t, &cres);
                                rbf->rbfa[n].chroma = c_encodeChroma(&cres);
                        } else
                                rbf->rbfa[n].chroma = c_dfchroma;
                        rbf->rbfa[n].crad = ANG2R(sqrt(rad2));
                        ovec_from_pos(v, rbf1j->gx, rbf1j->gy);
                        geodesic(v, v0, v, t, GEOD_REL);
                        pos_from_vec(pos, v);
                        rbf->rbfa[n].gx = pos[0];
                        rbf->rbfa[n].gy = pos[1];
                        ++n;
                }
        }
        rbf->vtotal *= mig->rbfv[0]->vtotal;    /* turn ratio into actual */
        return(rbf);
memerr:
        fprintf(stderr, "%s: Out of memory in e_advect_rbf()\n", progname);
        exit(1);
        return(NULL);   /* pro forma return */
}

/* Clear our BSDF representation and free memory */
void
clear_bsdf_rep(void)
{
        while (mig_list != NULL) {
                MIGRATION       *mig = mig_list;
                mig_list = mig->next;
                free(mig);
        }
        while (dsf_list != NULL) {
                RBFNODE         *rbf = dsf_list;
                dsf_list = rbf->next;
                free(rbf);
        }
        bsdf_name[0] = '\0';
        bsdf_manuf[0] = '\0';
        inp_coverage = 0;
        single_plane_incident = -1;
        input_orient = output_orient = 0;
        rbf_colorimetry = RBCunknown;
        grid_res = GRIDRES;
        memset(bsdf_hist, 0, sizeof(bsdf_hist));
        bsdf_min = 0;
        bsdf_spec_val = 0;
        bsdf_spec_rad = 0;
}

/* Write our BSDF mesh interpolant out to the given binary stream */
void
save_bsdf_rep(FILE *ofp)
{
        RBFNODE         *rbf;
        MIGRATION       *mig;
        int             i, n;
                                        /* finish header */
        if (bsdf_name[0])
                fprintf(ofp, "NAME=%s\n", bsdf_name);
        if (bsdf_manuf[0])
                fprintf(ofp, "MANUFACT=%s\n", bsdf_manuf);
        fprintf(ofp, "SYMMETRY=%d\n", !single_plane_incident * inp_coverage);
        fprintf(ofp, "IO_SIDES= %d %d\n", input_orient, output_orient);
        fprintf(ofp, "COLORIMETRY=%s\n", RBCident[rbf_colorimetry]);
        fprintf(ofp, "GRIDRES=%d\n", grid_res);
        fprintf(ofp, "BSDFMIN=%g\n", bsdf_min);
        if ((bsdf_spec_val > bsdf_min) & (bsdf_spec_rad > 0))
                fprintf(ofp, "BSDFSPEC= %f %f\n", bsdf_spec_val, bsdf_spec_rad);
        fputformat(BSDFREP_FMT, ofp);
        fputc('\n', ofp);
        putint(BSDFREP_MAGIC, 2, ofp);
                                        /* write each DSF */
        for (rbf = dsf_list; rbf != NULL; rbf = rbf->next) {
                putint(rbf->ord, 4, ofp);
                putflt(rbf->invec[0], ofp);
                putflt(rbf->invec[1], ofp);
                putflt(rbf->invec[2], ofp);
                putflt(rbf->vtotal, ofp);
                putint(rbf->nrbf, 4, ofp);
                for (i = 0; i < rbf->nrbf; i++) {
                        putflt(rbf->rbfa[i].peak, ofp);
                        putint(rbf->rbfa[i].chroma, 2, ofp);
                        putint(rbf->rbfa[i].crad, 2, ofp);
                        putint(rbf->rbfa[i].gx, 2, ofp);
                        putint(rbf->rbfa[i].gy, 2, ofp);
                }
        }
        putint(-1, 4, ofp);             /* terminator */
                                        /* write each migration matrix */
        for (mig = mig_list; mig != NULL; mig = mig->next) {
                int     zerocnt = 0;
                putint(mig->rbfv[0]->ord, 4, ofp);
                putint(mig->rbfv[1]->ord, 4, ofp);
                                        /* write out as sparse data */
                n = mtx_nrows(mig) * mtx_ncols(mig);
                for (i = 0; i < n; i++) {
                        if (zerocnt == 0xff) {
                                putint(0xff, 1, ofp); zerocnt = 0;
                        }
                        if (mig->mtx[i] != 0) {
                                putint(zerocnt, 1, ofp); zerocnt = 0;
                                putflt(mig->mtx[i], ofp);
                        } else
                                ++zerocnt;
                }
                putint(zerocnt, 1, ofp);
        }
        putint(-1, 4, ofp);             /* terminator */
        putint(-1, 4, ofp);
        if (fflush(ofp) == EOF) {
                fprintf(stderr, "%s: error writing BSDF interpolant\n",
                                progname);
                exit(1);
        }
}

/* Check header line for critical information */
static int
headline(char *s, void *p)
{
        char    fmt[MAXFMTLEN];
        int     i;

        if (isheadid(s))
                return(0);
        if (!strncmp(s, "NAME=", 5)) {
                strcpy(bsdf_name, s+5);
                bsdf_name[strlen(bsdf_name)-1] = '\0';
                return(1);
        }
        if (!strncmp(s, "MANUFACT=", 9)) {
                strcpy(bsdf_manuf, s+9);
                bsdf_manuf[strlen(bsdf_manuf)-1] = '\0';
                return(1);
        }
        if (!strncmp(s, "SYMMETRY=", 9)) {
                inp_coverage = atoi(s+9);
                single_plane_incident = !inp_coverage;
                return(1);
        }
        if (!strncmp(s, "IO_SIDES=", 9)) {
                sscanf(s+9, "%d %d", &input_orient, &output_orient);
                return(1);
        }
        if (!strncmp(s, "COLORIMETRY=", 12)) {
                fmt[0] = '\0';
                sscanf(s+12, "%s", fmt);
                for (i = RBCunknown; i >= 0; i--)
                        if (!strcmp(fmt, RBCident[i]))
                                break;
                if (i < 0)
                        return(-1);
                rbf_colorimetry = i;
                return(1);
        }
        if (!strncmp(s, "GRIDRES=", 8)) {
                sscanf(s+8, "%d", &grid_res);
                return(1);
        }
        if (!strncmp(s, "BSDFMIN=", 8)) {
                sscanf(s+8, "%lf", &bsdf_min);
                return(1);
        }
        if (!strncmp(s, "BSDFSPEC=", 9)) {
                sscanf(s+9, "%lf %lf", &bsdf_spec_val, &bsdf_spec_rad);
                return(1);
        }
        if (formatval(fmt, s))
                return (strcmp(fmt, BSDFREP_FMT) ? -1 : 0);
        if (sir_headshare != NULL)
                return ((*sir_headshare)(s));
        return(0);
}

/* Read a BSDF mesh interpolant from the given binary stream */
int
load_bsdf_rep(FILE *ifp)
{
        RBFNODE         rbfh;
        int             from_ord, to_ord;
        int             i;

        clear_bsdf_rep();
        if (ifp == NULL)
                return(0);
        if (getheader(ifp, headline, NULL) < 0 || (single_plane_incident < 0) |
                        !input_orient | !output_orient |
                        (grid_res < 16) | (grid_res > 0xffff)) {
                fprintf(stderr, "%s: missing/bad format for BSDF interpolant\n",
                                progname);
                return(0);
        }
        if (getint(2, ifp) != BSDFREP_MAGIC) {
                fprintf(stderr, "%s: bad magic number for BSDF interpolant\n",
                                progname);
                return(0);
        }
        memset(&rbfh, 0, sizeof(rbfh)); /* read each DSF */
        while ((rbfh.ord = getint(4, ifp)) >= 0) {
                RBFNODE         *newrbf;

                rbfh.invec[0] = getflt(ifp);
                rbfh.invec[1] = getflt(ifp);
                rbfh.invec[2] = getflt(ifp);
                if (normalize(rbfh.invec) == 0) {
                        fprintf(stderr, "%s: zero incident vector\n", progname);
                        return(0);
                }
                rbfh.vtotal = getflt(ifp);
                rbfh.nrbf = getint(4, ifp);
                newrbf = (RBFNODE *)malloc(sizeof(RBFNODE) +
                                        sizeof(RBFVAL)*(rbfh.nrbf-1));
                if (newrbf == NULL)
                        goto memerr;
                *newrbf = rbfh;
                for (i = 0; i < rbfh.nrbf; i++) {
                        newrbf->rbfa[i].peak = getflt(ifp);
                        newrbf->rbfa[i].chroma = getint(2, ifp) & 0xffff;
                        newrbf->rbfa[i].crad = getint(2, ifp) & 0xffff;
                        newrbf->rbfa[i].gx = getint(2, ifp) & 0xffff;
                        newrbf->rbfa[i].gy = getint(2, ifp) & 0xffff;
                }
                if (feof(ifp))
                        goto badEOF;
                                        /* insert in global list */
                if (insert_dsf(newrbf) != rbfh.ord) {
                        fprintf(stderr, "%s: error adding DSF\n", progname);
                        return(0);
                }
        }
                                        /* read each migration matrix */
        while ((from_ord = getint(4, ifp)) >= 0 &&
                        (to_ord = getint(4, ifp)) >= 0) {
                RBFNODE         *from_rbf = get_dsf(from_ord);
                RBFNODE         *to_rbf = get_dsf(to_ord);
                MIGRATION       *newmig;
                int             n;

                if ((from_rbf == NULL) | (to_rbf == NULL)) {
                        fprintf(stderr,
                                "%s: bad DSF reference in migration edge\n",
                                        progname);
                        return(0);
                }
                n = from_rbf->nrbf * to_rbf->nrbf;
                newmig = (MIGRATION *)malloc(sizeof(MIGRATION) +
                                                sizeof(float)*(n-1));
                if (newmig == NULL)
                        goto memerr;
                newmig->rbfv[0] = from_rbf;
                newmig->rbfv[1] = to_rbf;
                memset(newmig->mtx, 0, sizeof(float)*n);
                for (i = 0; ; ) {       /* read sparse data */
                        int     zc = getint(1, ifp) & 0xff;
                        if ((i += zc) >= n)
                                break;
                        if (zc == 0xff)
                                continue;
                        newmig->mtx[i++] = getflt(ifp);
                }
                if (feof(ifp))
                        goto badEOF;
                                        /* insert in edge lists */
                newmig->enxt[0] = from_rbf->ejl;
                from_rbf->ejl = newmig;
                newmig->enxt[1] = to_rbf->ejl;
                to_rbf->ejl = newmig;
                                        /* push onto global list */
                newmig->next = mig_list;
                mig_list = newmig;
        }
        return(1);                      /* success! */
memerr:
        fprintf(stderr, "%s: Out of memory in load_bsdf_rep()\n", progname);
        exit(1);
badEOF:
        fprintf(stderr, "%s: Unexpected EOF in load_bsdf_rep()\n", progname);
        return(0);
}
Revision:	2.35
Committed:	Tue Sep 7 20:13:13 2021 UTC (2 years, 8 months ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 2.34:	+3 -3 lines
Log Message:	fix(bsdf2ttree, bsdf2klems): reduced threshold to avoid "sticking" behavior in interpolant