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#ifndef lint
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static const char RCSid[] = "$Id: ambcomp.c,v 2.25 2014/04/11 20:31:37 greg Exp $";
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#endif
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/*
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* Routines to compute "ambient" values using Monte Carlo
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*
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* Declarations of external symbols in ambient.h
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*/
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#include "copyright.h"
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#include "ray.h"
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#include "ambient.h"
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#include "random.h"
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#ifdef NEWAMB
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extern void SDsquare2disk(double ds[2], double seedx, double seedy);
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typedef struct {
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RAY *rp; /* originating ray sample */
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FVECT ux, uy; /* tangent axis directions */
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int ns; /* number of samples per axis */
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COLOR acoef; /* division contribution coefficient */
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struct s_ambsamp {
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COLOR v; /* hemisphere sample value */
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float p[3]; /* intersection point */
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} sa[1]; /* sample array (extends struct) */
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} AMBHEMI; /* ambient sample hemisphere */
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#define ambsamp(h,i,j) (h)->sa[(i)*(h)->ns + (j)]
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static AMBHEMI *
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inithemi( /* initialize sampling hemisphere */
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COLOR ac,
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RAY *r,
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double wt
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)
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{
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AMBHEMI *hp;
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double d;
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int n, i;
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/* set number of divisions */
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if (ambacc <= FTINY &&
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wt > (d = 0.8*intens(ac)*r->rweight/(ambdiv*minweight)))
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wt = d; /* avoid ray termination */
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n = sqrt(ambdiv * wt) + 0.5;
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i = 1 + 4*(ambacc > FTINY); /* minimum number of samples */
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if (n < i)
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n = i;
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/* allocate sampling array */
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hp = (AMBHEMI *)malloc(sizeof(AMBHEMI) +
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sizeof(struct s_ambsamp)*(n*n - 1));
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if (hp == NULL)
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return(NULL);
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hp->rp = r;
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hp->ns = n;
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/* assign coefficient */
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copycolor(hp->acoef, ac);
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d = 1.0/(n*n);
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scalecolor(hp->acoef, d);
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/* make tangent axes */
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hp->uy[0] = hp->uy[1] = hp->uy[2] = 0.0;
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for (i = 0; i < 3; i++)
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if (r->rn[i] < 0.6 && r->rn[i] > -0.6)
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break;
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if (i >= 3)
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error(CONSISTENCY, "bad ray direction in inithemi()");
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hp->uy[i] = 1.0;
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VCROSS(hp->ux, hp->uy, r->rn);
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normalize(hp->ux);
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VCROSS(hp->uy, r->rn, hp->ux);
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/* we're ready to sample */
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return(hp);
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}
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static int
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ambsample( /* sample an ambient direction */
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AMBHEMI *hp,
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int i,
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int j,
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)
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{
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struct s_ambsamp *ap = &ambsamp(hp,i,j);
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RAY ar;
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int hlist[3];
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double spt[2], dz;
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int ii;
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/* ambient coefficient for weight */
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if (ambacc > FTINY)
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setcolor(ar.rcoef, AVGREFL, AVGREFL, AVGREFL);
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else
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copycolor(ar.rcoef, hp->acoef);
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if (rayorigin(&ar, AMBIENT, hp->rp, ar.rcoef) < 0) {
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setcolor(ap->v, 0., 0., 0.);
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ap->r = 0.;
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return(0); /* no sample taken */
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}
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if (ambacc > FTINY) {
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multcolor(ar.rcoef, hp->acoef);
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scalecolor(ar.rcoef, 1./AVGREFL);
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}
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/* generate hemispherical sample */
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SDsquare2disk(spt, (i+frandom())/hp->ns, (j+frandom())/hp->ns);
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zd = sqrt(1. - spt[0]*spt[0] - spt[1]*spt[1]);
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for (ii = 3; ii--; )
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ar.rdir[ii] = spt[0]*hp->ux[ii] +
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spt[1]*hp->uy[ii] +
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zd*hp->rp->ron[ii];
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checknorm(ar.rdir);
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dimlist[ndims++] = i*hp->ns + j + 90171;
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rayvalue(&ar); /* evaluate ray */
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ndims--;
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multcolor(ar.rcol, ar.rcoef); /* apply coefficient */
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copycolor(ap->v, ar.rcol);
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if (ar.rt > 20.0*maxarad) /* limit vertex distance */
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ar.rt = 20.0*maxarad;
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VSUM(ap->p, ar.rorg, ar.rdir, ar.rt);
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return(1);
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}
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static void
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ambHessian( /* anisotropic radii & pos. gradient */
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AMBHEMI *hp,
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FVECT uv[2], /* returned */
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float ra[2], /* returned */
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float pg[2] /* returned */
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)
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{
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if (ra != NULL) { /* compute Hessian-derived radii */
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} else { /* else copy original tangent axes */
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VCOPY(uv[0], hp->ux);
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VCOPY(uv[1], hp->uy);
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}
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if (pg == NULL) /* no position gradient requested? */
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return;
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}
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int
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doambient( /* compute ambient component */
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COLOR rcol, /* input/output color */
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RAY *r,
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double wt,
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FVECT uv[2], /* returned */
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float ra[2], /* returned */
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float pg[2], /* returned */
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float dg[2] /* returned */
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)
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{
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int cnt = 0;
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FVECT my_uv[2];
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AMBHEMI *hp;
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double d, acol[3];
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struct s_ambsamp *ap;
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int i, j;
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/* initialize */
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if ((hp = inithemi(rcol, r, wt)) == NULL)
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return(0);
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if (uv != NULL)
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memset(uv, 0, sizeof(FVECT)*2);
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if (ra != NULL)
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ra[0] = ra[1] = 0.0;
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if (pg != NULL)
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pg[0] = pg[1] = 0.0;
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if (dg != NULL)
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dg[0] = dg[1] = 0.0;
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/* sample the hemisphere */
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acol[0] = acol[1] = acol[2] = 0.0;
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for (i = hemi.ns; i--; )
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for (j = hemi.ns; j--; )
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if (ambsample(hp, i, j)) {
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ap = &ambsamp(hp,i,j);
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addcolor(acol, ap->v);
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++cnt;
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}
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if (!cnt) {
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setcolor(rcol, 0.0, 0.0, 0.0);
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free(hp);
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return(0); /* no valid samples */
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}
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d = 1.0 / cnt; /* final indirect irradiance/PI */
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acol[0] *= d; acol[1] *= d; acol[2] *= d;
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copycolor(rcol, acol);
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if (cnt < hp->ns*hp->ns || /* incomplete sampling? */
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(ra == NULL) & (pg == NULL) & (dg == NULL)) {
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free(hp);
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return(-1); /* no radius or gradient calc. */
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}
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d = 0.01 * bright(rcol); /* add in 1% before Hessian comp. */
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if (d < FTINY) d = FTINY;
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ap = hp->sa; /* using Y channel from here on... */
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for (i = hp->ns*hp->ns; i--; ap++)
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colval(ap->v,CIEY) = bright(ap->v) + d;
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if (uv == NULL) /* make sure we have axis pointers */
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uv = my_uv;
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/* compute radii & pos. gradient */
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ambHessian(hp, uv, ra, pg);
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if (dg != NULL) /* compute direction gradient */
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ambdirgrad(hp, uv, dg);
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if (ra != NULL) { /* adjust/clamp radii */
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d = pow(wt, -0.25);
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if ((ra[0] *= d) > maxarad)
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ra[0] = maxarad;
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if ((ra[1] *= d) > 2.0*ra[0])
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ra[1] = 2.0*ra[0];
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}
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free(hp); /* clean up and return */
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return(1);
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}
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#else /* ! NEWAMB */
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void
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inithemi( /* initialize sampling hemisphere */
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AMBHEMI *hp,
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COLOR ac,
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RAY *r,
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double wt
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)
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{
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double d;
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int i;
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/* set number of divisions */
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if (ambacc <= FTINY &&
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wt > (d = 0.8*intens(ac)*r->rweight/(ambdiv*minweight)))
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wt = d; /* avoid ray termination */
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hp->nt = sqrt(ambdiv * wt / PI) + 0.5;
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i = ambacc > FTINY ? 3 : 1; /* minimum number of samples */
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if (hp->nt < i)
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hp->nt = i;
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hp->np = PI * hp->nt + 0.5;
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/* set number of super-samples */
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hp->ns = ambssamp * wt + 0.5;
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/* assign coefficient */
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copycolor(hp->acoef, ac);
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d = 1.0/(hp->nt*hp->np);
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scalecolor(hp->acoef, d);
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/* make axes */
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VCOPY(hp->uz, r->ron);
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hp->uy[0] = hp->uy[1] = hp->uy[2] = 0.0;
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for (i = 0; i < 3; i++)
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if (hp->uz[i] < 0.6 && hp->uz[i] > -0.6)
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break;
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if (i >= 3)
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error(CONSISTENCY, "bad ray direction in inithemi");
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hp->uy[i] = 1.0;
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fcross(hp->ux, hp->uy, hp->uz);
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normalize(hp->ux);
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fcross(hp->uy, hp->uz, hp->ux);
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}
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int
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divsample( /* sample a division */
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AMBSAMP *dp,
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AMBHEMI *h,
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RAY *r
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)
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{
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RAY ar;
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int hlist[3];
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double spt[2];
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double xd, yd, zd;
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double b2;
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double phi;
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int i;
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/* ambient coefficient for weight */
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if (ambacc > FTINY)
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setcolor(ar.rcoef, AVGREFL, AVGREFL, AVGREFL);
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else
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copycolor(ar.rcoef, h->acoef);
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if (rayorigin(&ar, AMBIENT, r, ar.rcoef) < 0)
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return(-1);
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if (ambacc > FTINY) {
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multcolor(ar.rcoef, h->acoef);
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scalecolor(ar.rcoef, 1./AVGREFL);
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}
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hlist[0] = r->rno;
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hlist[1] = dp->t;
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hlist[2] = dp->p;
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multisamp(spt, 2, urand(ilhash(hlist,3)+dp->n));
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zd = sqrt((dp->t + spt[0])/h->nt);
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phi = 2.0*PI * (dp->p + spt[1])/h->np;
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xd = tcos(phi) * zd;
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yd = tsin(phi) * zd;
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zd = sqrt(1.0 - zd*zd);
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for (i = 0; i < 3; i++)
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ar.rdir[i] = xd*h->ux[i] +
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yd*h->uy[i] +
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zd*h->uz[i];
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checknorm(ar.rdir);
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dimlist[ndims++] = dp->t*h->np + dp->p + 90171;
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rayvalue(&ar);
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ndims--;
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multcolor(ar.rcol, ar.rcoef); /* apply coefficient */
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addcolor(dp->v, ar.rcol);
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/* use rt to improve gradient calc */
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if (ar.rt > FTINY && ar.rt < FHUGE)
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dp->r += 1.0/ar.rt;
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/* (re)initialize error */
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if (dp->n++) {
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b2 = bright(dp->v)/dp->n - bright(ar.rcol);
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b2 = b2*b2 + dp->k*((dp->n-1)*(dp->n-1));
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dp->k = b2/(dp->n*dp->n);
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} else
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dp->k = 0.0;
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return(0);
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}
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static int
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ambcmp( /* decreasing order */
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const void *p1,
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| 320 |
const void *p2
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)
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| 322 |
{
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const AMBSAMP *d1 = (const AMBSAMP *)p1;
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const AMBSAMP *d2 = (const AMBSAMP *)p2;
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if (d1->k < d2->k)
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| 327 |
return(1);
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| 328 |
if (d1->k > d2->k)
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return(-1);
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return(0);
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| 331 |
}
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| 332 |
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| 333 |
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| 334 |
static int
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ambnorm( /* standard order */
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| 336 |
const void *p1,
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| 337 |
const void *p2
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| 338 |
)
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| 339 |
{
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| 340 |
const AMBSAMP *d1 = (const AMBSAMP *)p1;
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| 341 |
const AMBSAMP *d2 = (const AMBSAMP *)p2;
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| 342 |
int c;
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| 343 |
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| 344 |
if ( (c = d1->t - d2->t) )
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| 345 |
return(c);
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| 346 |
return(d1->p - d2->p);
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| 347 |
}
|
| 348 |
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| 349 |
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| 350 |
double
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| 351 |
doambient( /* compute ambient component */
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| 352 |
COLOR rcol,
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| 353 |
RAY *r,
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| 354 |
double wt,
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| 355 |
FVECT pg,
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| 356 |
FVECT dg
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| 357 |
)
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| 358 |
{
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| 359 |
double b, d=0;
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| 360 |
AMBHEMI hemi;
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| 361 |
AMBSAMP *div;
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| 362 |
AMBSAMP dnew;
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| 363 |
double acol[3];
|
| 364 |
AMBSAMP *dp;
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| 365 |
double arad;
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| 366 |
int divcnt;
|
| 367 |
int i, j;
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| 368 |
/* initialize hemisphere */
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| 369 |
inithemi(&hemi, rcol, r, wt);
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| 370 |
divcnt = hemi.nt * hemi.np;
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| 371 |
/* initialize */
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| 372 |
if (pg != NULL)
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| 373 |
pg[0] = pg[1] = pg[2] = 0.0;
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| 374 |
if (dg != NULL)
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| 375 |
dg[0] = dg[1] = dg[2] = 0.0;
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| 376 |
setcolor(rcol, 0.0, 0.0, 0.0);
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| 377 |
if (divcnt == 0)
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| 378 |
return(0.0);
|
| 379 |
/* allocate super-samples */
|
| 380 |
if (hemi.ns > 0 || pg != NULL || dg != NULL) {
|
| 381 |
div = (AMBSAMP *)malloc(divcnt*sizeof(AMBSAMP));
|
| 382 |
if (div == NULL)
|
| 383 |
error(SYSTEM, "out of memory in doambient");
|
| 384 |
} else
|
| 385 |
div = NULL;
|
| 386 |
/* sample the divisions */
|
| 387 |
arad = 0.0;
|
| 388 |
acol[0] = acol[1] = acol[2] = 0.0;
|
| 389 |
if ((dp = div) == NULL)
|
| 390 |
dp = &dnew;
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| 391 |
divcnt = 0;
|
| 392 |
for (i = 0; i < hemi.nt; i++)
|
| 393 |
for (j = 0; j < hemi.np; j++) {
|
| 394 |
dp->t = i; dp->p = j;
|
| 395 |
setcolor(dp->v, 0.0, 0.0, 0.0);
|
| 396 |
dp->r = 0.0;
|
| 397 |
dp->n = 0;
|
| 398 |
if (divsample(dp, &hemi, r) < 0) {
|
| 399 |
if (div != NULL)
|
| 400 |
dp++;
|
| 401 |
continue;
|
| 402 |
}
|
| 403 |
arad += dp->r;
|
| 404 |
divcnt++;
|
| 405 |
if (div != NULL)
|
| 406 |
dp++;
|
| 407 |
else
|
| 408 |
addcolor(acol, dp->v);
|
| 409 |
}
|
| 410 |
if (!divcnt) {
|
| 411 |
if (div != NULL)
|
| 412 |
free((void *)div);
|
| 413 |
return(0.0); /* no samples taken */
|
| 414 |
}
|
| 415 |
if (divcnt < hemi.nt*hemi.np) {
|
| 416 |
pg = dg = NULL; /* incomplete sampling */
|
| 417 |
hemi.ns = 0;
|
| 418 |
} else if (arad > FTINY && divcnt/arad < minarad) {
|
| 419 |
hemi.ns = 0; /* close enough */
|
| 420 |
} else if (hemi.ns > 0) { /* else perform super-sampling? */
|
| 421 |
comperrs(div, &hemi); /* compute errors */
|
| 422 |
qsort(div, divcnt, sizeof(AMBSAMP), ambcmp); /* sort divs */
|
| 423 |
/* super-sample */
|
| 424 |
for (i = hemi.ns; i > 0; i--) {
|
| 425 |
dnew = *div;
|
| 426 |
if (divsample(&dnew, &hemi, r) < 0) {
|
| 427 |
dp++;
|
| 428 |
continue;
|
| 429 |
}
|
| 430 |
dp = div; /* reinsert */
|
| 431 |
j = divcnt < i ? divcnt : i;
|
| 432 |
while (--j > 0 && dnew.k < dp[1].k) {
|
| 433 |
*dp = *(dp+1);
|
| 434 |
dp++;
|
| 435 |
}
|
| 436 |
*dp = dnew;
|
| 437 |
}
|
| 438 |
if (pg != NULL || dg != NULL) /* restore order */
|
| 439 |
qsort(div, divcnt, sizeof(AMBSAMP), ambnorm);
|
| 440 |
}
|
| 441 |
/* compute returned values */
|
| 442 |
if (div != NULL) {
|
| 443 |
arad = 0.0; /* note: divcnt may be < nt*np */
|
| 444 |
for (i = hemi.nt*hemi.np, dp = div; i-- > 0; dp++) {
|
| 445 |
arad += dp->r;
|
| 446 |
if (dp->n > 1) {
|
| 447 |
b = 1.0/dp->n;
|
| 448 |
scalecolor(dp->v, b);
|
| 449 |
dp->r *= b;
|
| 450 |
dp->n = 1;
|
| 451 |
}
|
| 452 |
addcolor(acol, dp->v);
|
| 453 |
}
|
| 454 |
b = bright(acol);
|
| 455 |
if (b > FTINY) {
|
| 456 |
b = 1.0/b; /* compute & normalize gradient(s) */
|
| 457 |
if (pg != NULL) {
|
| 458 |
posgradient(pg, div, &hemi);
|
| 459 |
for (i = 0; i < 3; i++)
|
| 460 |
pg[i] *= b;
|
| 461 |
}
|
| 462 |
if (dg != NULL) {
|
| 463 |
dirgradient(dg, div, &hemi);
|
| 464 |
for (i = 0; i < 3; i++)
|
| 465 |
dg[i] *= b;
|
| 466 |
}
|
| 467 |
}
|
| 468 |
free((void *)div);
|
| 469 |
}
|
| 470 |
copycolor(rcol, acol);
|
| 471 |
if (arad <= FTINY)
|
| 472 |
arad = maxarad;
|
| 473 |
else
|
| 474 |
arad = (divcnt+hemi.ns)/arad;
|
| 475 |
if (pg != NULL) { /* reduce radius if gradient large */
|
| 476 |
d = DOT(pg,pg);
|
| 477 |
if (d*arad*arad > 1.0)
|
| 478 |
arad = 1.0/sqrt(d);
|
| 479 |
}
|
| 480 |
if (arad < minarad) {
|
| 481 |
arad = minarad;
|
| 482 |
if (pg != NULL && d*arad*arad > 1.0) { /* cap gradient */
|
| 483 |
d = 1.0/arad/sqrt(d);
|
| 484 |
for (i = 0; i < 3; i++)
|
| 485 |
pg[i] *= d;
|
| 486 |
}
|
| 487 |
}
|
| 488 |
if ((arad /= sqrt(wt)) > maxarad)
|
| 489 |
arad = maxarad;
|
| 490 |
return(arad);
|
| 491 |
}
|
| 492 |
|
| 493 |
|
| 494 |
void
|
| 495 |
comperrs( /* compute initial error estimates */
|
| 496 |
AMBSAMP *da, /* assumes standard ordering */
|
| 497 |
AMBHEMI *hp
|
| 498 |
)
|
| 499 |
{
|
| 500 |
double b, b2;
|
| 501 |
int i, j;
|
| 502 |
AMBSAMP *dp;
|
| 503 |
/* sum differences from neighbors */
|
| 504 |
dp = da;
|
| 505 |
for (i = 0; i < hp->nt; i++)
|
| 506 |
for (j = 0; j < hp->np; j++) {
|
| 507 |
#ifdef DEBUG
|
| 508 |
if (dp->t != i || dp->p != j)
|
| 509 |
error(CONSISTENCY,
|
| 510 |
"division order in comperrs");
|
| 511 |
#endif
|
| 512 |
b = bright(dp[0].v);
|
| 513 |
if (i > 0) { /* from above */
|
| 514 |
b2 = bright(dp[-hp->np].v) - b;
|
| 515 |
b2 *= b2 * 0.25;
|
| 516 |
dp[0].k += b2;
|
| 517 |
dp[-hp->np].k += b2;
|
| 518 |
}
|
| 519 |
if (j > 0) { /* from behind */
|
| 520 |
b2 = bright(dp[-1].v) - b;
|
| 521 |
b2 *= b2 * 0.25;
|
| 522 |
dp[0].k += b2;
|
| 523 |
dp[-1].k += b2;
|
| 524 |
} else { /* around */
|
| 525 |
b2 = bright(dp[hp->np-1].v) - b;
|
| 526 |
b2 *= b2 * 0.25;
|
| 527 |
dp[0].k += b2;
|
| 528 |
dp[hp->np-1].k += b2;
|
| 529 |
}
|
| 530 |
dp++;
|
| 531 |
}
|
| 532 |
/* divide by number of neighbors */
|
| 533 |
dp = da;
|
| 534 |
for (j = 0; j < hp->np; j++) /* top row */
|
| 535 |
(dp++)->k *= 1.0/3.0;
|
| 536 |
if (hp->nt < 2)
|
| 537 |
return;
|
| 538 |
for (i = 1; i < hp->nt-1; i++) /* central region */
|
| 539 |
for (j = 0; j < hp->np; j++)
|
| 540 |
(dp++)->k *= 0.25;
|
| 541 |
for (j = 0; j < hp->np; j++) /* bottom row */
|
| 542 |
(dp++)->k *= 1.0/3.0;
|
| 543 |
}
|
| 544 |
|
| 545 |
|
| 546 |
void
|
| 547 |
posgradient( /* compute position gradient */
|
| 548 |
FVECT gv,
|
| 549 |
AMBSAMP *da, /* assumes standard ordering */
|
| 550 |
AMBHEMI *hp
|
| 551 |
)
|
| 552 |
{
|
| 553 |
int i, j;
|
| 554 |
double nextsine, lastsine, b, d;
|
| 555 |
double mag0, mag1;
|
| 556 |
double phi, cosp, sinp, xd, yd;
|
| 557 |
AMBSAMP *dp;
|
| 558 |
|
| 559 |
xd = yd = 0.0;
|
| 560 |
for (j = 0; j < hp->np; j++) {
|
| 561 |
dp = da + j;
|
| 562 |
mag0 = mag1 = 0.0;
|
| 563 |
lastsine = 0.0;
|
| 564 |
for (i = 0; i < hp->nt; i++) {
|
| 565 |
#ifdef DEBUG
|
| 566 |
if (dp->t != i || dp->p != j)
|
| 567 |
error(CONSISTENCY,
|
| 568 |
"division order in posgradient");
|
| 569 |
#endif
|
| 570 |
b = bright(dp->v);
|
| 571 |
if (i > 0) {
|
| 572 |
d = dp[-hp->np].r;
|
| 573 |
if (dp[0].r > d) d = dp[0].r;
|
| 574 |
/* sin(t)*cos(t)^2 */
|
| 575 |
d *= lastsine * (1.0 - (double)i/hp->nt);
|
| 576 |
mag0 += d*(b - bright(dp[-hp->np].v));
|
| 577 |
}
|
| 578 |
nextsine = sqrt((double)(i+1)/hp->nt);
|
| 579 |
if (j > 0) {
|
| 580 |
d = dp[-1].r;
|
| 581 |
if (dp[0].r > d) d = dp[0].r;
|
| 582 |
mag1 += d * (nextsine - lastsine) *
|
| 583 |
(b - bright(dp[-1].v));
|
| 584 |
} else {
|
| 585 |
d = dp[hp->np-1].r;
|
| 586 |
if (dp[0].r > d) d = dp[0].r;
|
| 587 |
mag1 += d * (nextsine - lastsine) *
|
| 588 |
(b - bright(dp[hp->np-1].v));
|
| 589 |
}
|
| 590 |
dp += hp->np;
|
| 591 |
lastsine = nextsine;
|
| 592 |
}
|
| 593 |
mag0 *= 2.0*PI / hp->np;
|
| 594 |
phi = 2.0*PI * (double)j/hp->np;
|
| 595 |
cosp = tcos(phi); sinp = tsin(phi);
|
| 596 |
xd += mag0*cosp - mag1*sinp;
|
| 597 |
yd += mag0*sinp + mag1*cosp;
|
| 598 |
}
|
| 599 |
for (i = 0; i < 3; i++)
|
| 600 |
gv[i] = (xd*hp->ux[i] + yd*hp->uy[i])*(hp->nt*hp->np)/PI;
|
| 601 |
}
|
| 602 |
|
| 603 |
|
| 604 |
void
|
| 605 |
dirgradient( /* compute direction gradient */
|
| 606 |
FVECT gv,
|
| 607 |
AMBSAMP *da, /* assumes standard ordering */
|
| 608 |
AMBHEMI *hp
|
| 609 |
)
|
| 610 |
{
|
| 611 |
int i, j;
|
| 612 |
double mag;
|
| 613 |
double phi, xd, yd;
|
| 614 |
AMBSAMP *dp;
|
| 615 |
|
| 616 |
xd = yd = 0.0;
|
| 617 |
for (j = 0; j < hp->np; j++) {
|
| 618 |
dp = da + j;
|
| 619 |
mag = 0.0;
|
| 620 |
for (i = 0; i < hp->nt; i++) {
|
| 621 |
#ifdef DEBUG
|
| 622 |
if (dp->t != i || dp->p != j)
|
| 623 |
error(CONSISTENCY,
|
| 624 |
"division order in dirgradient");
|
| 625 |
#endif
|
| 626 |
/* tan(t) */
|
| 627 |
mag += bright(dp->v)/sqrt(hp->nt/(i+.5) - 1.0);
|
| 628 |
dp += hp->np;
|
| 629 |
}
|
| 630 |
phi = 2.0*PI * (j+.5)/hp->np + PI/2.0;
|
| 631 |
xd += mag * tcos(phi);
|
| 632 |
yd += mag * tsin(phi);
|
| 633 |
}
|
| 634 |
for (i = 0; i < 3; i++)
|
| 635 |
gv[i] = xd*hp->ux[i] + yd*hp->uy[i];
|
| 636 |
}
|
| 637 |
|
| 638 |
#endif /* ! NEWAMB */
|
