| 1 |
#ifndef lint
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| 2 |
static const char RCSid[] = "$Id: bsdf.c,v 2.3 2010/07/03 02:50:22 greg Exp $";
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| 3 |
#endif
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| 4 |
/*
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| 5 |
* Routines for handling BSDF data
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| 6 |
*/
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| 7 |
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| 8 |
#include "standard.h"
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| 9 |
#include "bsdf.h"
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#include "paths.h"
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#include "ezxml.h"
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#include <ctype.h>
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| 14 |
#define MAXLATS 46 /* maximum number of latitudes */
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| 15 |
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/* BSDF angle specification */
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typedef struct {
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char name[64]; /* basis name */
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| 19 |
int nangles; /* total number of directions */
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struct {
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float tmin; /* starting theta */
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short nphis; /* number of phis (0 term) */
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} lat[MAXLATS+1]; /* latitudes */
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} ANGLE_BASIS;
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#define MAXABASES 7 /* limit on defined bases */
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static ANGLE_BASIS abase_list[MAXABASES] = {
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{
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| 30 |
"LBNL/Klems Full", 145,
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{ {-5., 1},
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{5., 8},
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| 33 |
{15., 16},
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| 34 |
{25., 20},
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{35., 24},
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{45., 24},
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| 37 |
{55., 24},
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{65., 16},
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| 39 |
{75., 12},
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{90., 0} }
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}, {
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"LBNL/Klems Half", 73,
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{ {-6.5, 1},
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{6.5, 8},
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{19.5, 12},
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{32.5, 16},
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{46.5, 20},
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{61.5, 12},
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{76.5, 4},
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{90., 0} }
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}, {
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"LBNL/Klems Quarter", 41,
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{ {-9., 1},
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{9., 8},
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{27., 12},
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{46., 12},
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{66., 8},
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{90., 0} }
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}
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};
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static int nabases = 3; /* current number of defined bases */
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#define FEQ(a,b) ((a)-(b) <= 1e-7 && (b)-(a) <= 1e-7)
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// returns the name of the given tag
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#ifdef ezxml_name
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#undef ezxml_name
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static char *
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ezxml_name(ezxml_t xml)
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{
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if (xml == NULL)
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return(NULL);
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return(xml->name);
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}
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#endif
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// returns the given tag's character content or empty string if none
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#ifdef ezxml_txt
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#undef ezxml_txt
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static char *
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ezxml_txt(ezxml_t xml)
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{
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if (xml == NULL)
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return("");
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return(xml->txt);
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}
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#endif
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| 90 |
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static int
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ab_getvec( /* get vector for this angle basis index */
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FVECT v,
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int ndx,
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void *p
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)
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{
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| 98 |
ANGLE_BASIS *ab = (ANGLE_BASIS *)p;
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int li;
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double pol, azi, d;
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if ((ndx < 0) | (ndx >= ab->nangles))
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return(0);
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for (li = 0; ndx >= ab->lat[li].nphis; li++)
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ndx -= ab->lat[li].nphis;
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pol = PI/180.*0.5*(ab->lat[li].tmin + ab->lat[li+1].tmin);
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azi = 2.*PI*ndx/ab->lat[li].nphis;
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v[2] = d = cos(pol);
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d = sqrt(1. - d*d); /* sin(pol) */
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v[0] = cos(azi)*d;
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v[1] = sin(azi)*d;
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return(1);
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}
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static int
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ab_getndx( /* get index corresponding to the given vector */
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FVECT v,
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void *p
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)
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{
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ANGLE_BASIS *ab = (ANGLE_BASIS *)p;
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int li, ndx;
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double pol, azi, d;
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if ((v[2] < -1.0) | (v[2] > 1.0))
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return(-1);
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pol = 180.0/PI*acos(v[2]);
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azi = 180.0/PI*atan2(v[1], v[0]);
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if (azi < 0.0) azi += 360.0;
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for (li = 1; ab->lat[li].tmin <= pol; li++)
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if (!ab->lat[li].nphis)
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return(-1);
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--li;
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ndx = (int)((1./360.)*azi*ab->lat[li].nphis + 0.5);
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if (ndx >= ab->lat[li].nphis) ndx = 0;
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while (li--)
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ndx += ab->lat[li].nphis;
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return(ndx);
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}
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static double
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ab_getohm( /* get solid angle for this angle basis index */
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int ndx,
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void *p
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)
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{
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ANGLE_BASIS *ab = (ANGLE_BASIS *)p;
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int li;
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double theta, theta1;
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if ((ndx < 0) | (ndx >= ab->nangles))
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return(0);
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for (li = 0; ndx >= ab->lat[li].nphis; li++)
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ndx -= ab->lat[li].nphis;
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theta1 = PI/180. * ab->lat[li+1].tmin;
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if (ab->lat[li].nphis == 1) { /* special case */
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if (ab->lat[li].tmin > FTINY)
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error(USER, "unsupported BSDF coordinate system");
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return(2.*PI*(1. - cos(theta1)));
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}
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theta = PI/180. * ab->lat[li].tmin;
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return(2.*PI*(cos(theta) - cos(theta1))/(double)ab->lat[li].nphis);
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}
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static int
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ab_getvecR( /* get reverse vector for this angle basis index */
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FVECT v,
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int ndx,
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void *p
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)
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{
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if (!ab_getvec(v, ndx, p))
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return(0);
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v[0] = -v[0];
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v[1] = -v[1];
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v[2] = -v[2];
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return(1);
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}
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static int
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ab_getndxR( /* get index corresponding to the reverse vector */
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FVECT v,
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void *p
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)
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{
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FVECT v2;
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v2[0] = -v[0];
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v2[1] = -v[1];
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v2[2] = -v[2];
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return ab_getndx(v2, p);
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}
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static void
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load_angle_basis( /* load custom BSDF angle basis */
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ezxml_t wab
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)
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{
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char *abname = ezxml_txt(ezxml_child(wab, "AngleBasisName"));
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ezxml_t wbb;
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int i;
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if (!abname || !*abname)
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return;
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for (i = nabases; i--; )
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if (!strcmp(abname, abase_list[i].name))
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return; /* assume it's the same */
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if (nabases >= MAXABASES)
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error(INTERNAL, "too many angle bases");
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strcpy(abase_list[nabases].name, abname);
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abase_list[nabases].nangles = 0;
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for (i = 0, wbb = ezxml_child(wab, "AngleBasisBlock");
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wbb != NULL; i++, wbb = wbb->next) {
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if (i >= MAXLATS)
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error(INTERNAL, "too many latitudes in custom basis");
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abase_list[nabases].lat[i+1].tmin = atof(ezxml_txt(
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| 225 |
ezxml_child(ezxml_child(wbb,
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"ThetaBounds"), "UpperTheta")));
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| 227 |
if (!i)
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abase_list[nabases].lat[i].tmin =
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-abase_list[nabases].lat[i+1].tmin;
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else if (!FEQ(atof(ezxml_txt(ezxml_child(ezxml_child(wbb,
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"ThetaBounds"), "LowerTheta"))),
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abase_list[nabases].lat[i].tmin))
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error(WARNING, "theta values disagree in custom basis");
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abase_list[nabases].nangles +=
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abase_list[nabases].lat[i].nphis =
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atoi(ezxml_txt(ezxml_child(wbb, "nPhis")));
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}
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abase_list[nabases++].lat[i].nphis = 0;
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}
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| 240 |
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| 241 |
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static void
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load_bsdf_data( /* load BSDF distribution for this wavelength */
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| 244 |
struct BSDF_data *dp,
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| 245 |
ezxml_t wdb
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| 246 |
)
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| 247 |
{
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| 248 |
char *cbasis = ezxml_txt(ezxml_child(wdb,"ColumnAngleBasis"));
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| 249 |
char *rbasis = ezxml_txt(ezxml_child(wdb,"RowAngleBasis"));
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| 250 |
char *sdata;
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| 251 |
int i;
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| 252 |
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| 253 |
if ((!cbasis || !*cbasis) | (!rbasis || !*rbasis)) {
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| 254 |
error(WARNING, "missing column/row basis for BSDF");
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| 255 |
return;
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}
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| 257 |
for (i = nabases; i--; )
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| 258 |
if (!strcmp(cbasis, abase_list[i].name)) {
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| 259 |
dp->ninc = abase_list[i].nangles;
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| 260 |
dp->ib_priv = (void *)&abase_list[i];
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dp->ib_vec = ab_getvecR;
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dp->ib_ndx = ab_getndxR;
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| 263 |
dp->ib_ohm = ab_getohm;
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break;
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| 265 |
}
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| 266 |
if (i < 0) {
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| 267 |
sprintf(errmsg, "undefined ColumnAngleBasis '%s'", cbasis);
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| 268 |
error(WARNING, errmsg);
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| 269 |
return;
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| 270 |
}
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| 271 |
for (i = nabases; i--; )
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| 272 |
if (!strcmp(rbasis, abase_list[i].name)) {
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| 273 |
dp->nout = abase_list[i].nangles;
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| 274 |
dp->ob_priv = (void *)&abase_list[i];
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| 275 |
dp->ob_vec = ab_getvec;
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| 276 |
dp->ob_ndx = ab_getndx;
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| 277 |
dp->ob_ohm = ab_getohm;
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| 278 |
break;
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| 279 |
}
|
| 280 |
if (i < 0) {
|
| 281 |
sprintf(errmsg, "undefined RowAngleBasis '%s'", cbasis);
|
| 282 |
error(WARNING, errmsg);
|
| 283 |
return;
|
| 284 |
}
|
| 285 |
/* read BSDF data */
|
| 286 |
sdata = ezxml_txt(ezxml_child(wdb,"ScatteringData"));
|
| 287 |
if (!sdata || !*sdata) {
|
| 288 |
error(WARNING, "missing BSDF ScatteringData");
|
| 289 |
return;
|
| 290 |
}
|
| 291 |
dp->bsdf = (float *)malloc(sizeof(float)*dp->ninc*dp->nout);
|
| 292 |
if (dp->bsdf == NULL)
|
| 293 |
error(SYSTEM, "out of memory in load_bsdf_data");
|
| 294 |
for (i = 0; i < dp->ninc*dp->nout; i++) {
|
| 295 |
char *sdnext = fskip(sdata);
|
| 296 |
if (sdnext == NULL) {
|
| 297 |
error(WARNING, "bad/missing BSDF ScatteringData");
|
| 298 |
free(dp->bsdf); dp->bsdf = NULL;
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| 299 |
return;
|
| 300 |
}
|
| 301 |
while (*sdnext && isspace(*sdnext))
|
| 302 |
sdnext++;
|
| 303 |
if (*sdnext == ',') sdnext++;
|
| 304 |
dp->bsdf[i] = atof(sdata);
|
| 305 |
sdata = sdnext;
|
| 306 |
}
|
| 307 |
while (isspace(*sdata))
|
| 308 |
sdata++;
|
| 309 |
if (*sdata) {
|
| 310 |
sprintf(errmsg, "%d extra characters after BSDF ScatteringData",
|
| 311 |
strlen(sdata));
|
| 312 |
error(WARNING, errmsg);
|
| 313 |
}
|
| 314 |
}
|
| 315 |
|
| 316 |
|
| 317 |
static int
|
| 318 |
check_bsdf_data( /* check that BSDF data is sane */
|
| 319 |
struct BSDF_data *dp
|
| 320 |
)
|
| 321 |
{
|
| 322 |
double *omega_iarr, *omega_oarr;
|
| 323 |
double dom, contrib, hemi_total;
|
| 324 |
int nneg;
|
| 325 |
FVECT v;
|
| 326 |
int i, o;
|
| 327 |
|
| 328 |
if (dp == NULL || dp->bsdf == NULL)
|
| 329 |
return(0);
|
| 330 |
omega_iarr = (double *)calloc(dp->ninc, sizeof(double));
|
| 331 |
omega_oarr = (double *)calloc(dp->nout, sizeof(double));
|
| 332 |
if ((omega_iarr == NULL) | (omega_oarr == NULL))
|
| 333 |
error(SYSTEM, "out of memory in check_bsdf_data");
|
| 334 |
/* incoming projected solid angles */
|
| 335 |
hemi_total = .0;
|
| 336 |
for (i = dp->ninc; i--; ) {
|
| 337 |
dom = getBSDF_incohm(dp,i);
|
| 338 |
if (dom <= .0) {
|
| 339 |
error(WARNING, "zero/negative incoming solid angle");
|
| 340 |
continue;
|
| 341 |
}
|
| 342 |
if (!getBSDF_incvec(v,dp,i) || v[2] > FTINY) {
|
| 343 |
error(WARNING, "illegal incoming BSDF direction");
|
| 344 |
free(omega_iarr); free(omega_oarr);
|
| 345 |
return(0);
|
| 346 |
}
|
| 347 |
hemi_total += omega_iarr[i] = dom * -v[2];
|
| 348 |
}
|
| 349 |
if ((hemi_total > 1.02*PI) | (hemi_total < 0.98*PI)) {
|
| 350 |
sprintf(errmsg, "incoming BSDF hemisphere off by %.1f%%",
|
| 351 |
100.*(hemi_total/PI - 1.));
|
| 352 |
error(WARNING, errmsg);
|
| 353 |
}
|
| 354 |
dom = PI / hemi_total; /* fix normalization */
|
| 355 |
for (i = dp->ninc; i--; )
|
| 356 |
omega_iarr[i] *= dom;
|
| 357 |
/* outgoing projected solid angles */
|
| 358 |
hemi_total = .0;
|
| 359 |
for (o = dp->nout; o--; ) {
|
| 360 |
dom = getBSDF_outohm(dp,o);
|
| 361 |
if (dom <= .0) {
|
| 362 |
error(WARNING, "zero/negative outgoing solid angle");
|
| 363 |
continue;
|
| 364 |
}
|
| 365 |
if (!getBSDF_outvec(v,dp,o) || v[2] < -FTINY) {
|
| 366 |
error(WARNING, "illegal outgoing BSDF direction");
|
| 367 |
free(omega_iarr); free(omega_oarr);
|
| 368 |
return(0);
|
| 369 |
}
|
| 370 |
hemi_total += omega_oarr[o] = dom * v[2];
|
| 371 |
}
|
| 372 |
if ((hemi_total > 1.02*PI) | (hemi_total < 0.98*PI)) {
|
| 373 |
sprintf(errmsg, "outgoing BSDF hemisphere off by %.1f%%",
|
| 374 |
100.*(hemi_total/PI - 1.));
|
| 375 |
error(WARNING, errmsg);
|
| 376 |
}
|
| 377 |
dom = PI / hemi_total; /* fix normalization */
|
| 378 |
for (o = dp->nout; o--; )
|
| 379 |
omega_oarr[o] *= dom;
|
| 380 |
nneg = 0; /* check outgoing totals */
|
| 381 |
for (i = 0; i < dp->ninc; i++) {
|
| 382 |
hemi_total = .0;
|
| 383 |
for (o = dp->nout; o--; ) {
|
| 384 |
double f = BSDF_value(dp,i,o);
|
| 385 |
if (f >= .0)
|
| 386 |
hemi_total += f*omega_oarr[o];
|
| 387 |
else {
|
| 388 |
nneg += (f < -FTINY);
|
| 389 |
BSDF_value(dp,i,o) = .0f;
|
| 390 |
}
|
| 391 |
}
|
| 392 |
if (hemi_total > 1.02) {
|
| 393 |
sprintf(errmsg,
|
| 394 |
"incoming BSDF direction %d passes %.1f%% of light",
|
| 395 |
i, 100.*hemi_total);
|
| 396 |
error(WARNING, errmsg);
|
| 397 |
}
|
| 398 |
}
|
| 399 |
if (nneg) {
|
| 400 |
sprintf(errmsg, "%d negative BSDF values (ignored)", nneg);
|
| 401 |
error(WARNING, errmsg);
|
| 402 |
}
|
| 403 |
/* reverse roles and check again */
|
| 404 |
for (o = 0; o < dp->nout; o++) {
|
| 405 |
hemi_total = .0;
|
| 406 |
for (i = dp->ninc; i--; )
|
| 407 |
hemi_total += BSDF_value(dp,i,o) * omega_iarr[i];
|
| 408 |
|
| 409 |
if (hemi_total > 1.02) {
|
| 410 |
sprintf(errmsg,
|
| 411 |
"outgoing BSDF direction %d collects %.1f%% of light",
|
| 412 |
o, 100.*hemi_total);
|
| 413 |
error(WARNING, errmsg);
|
| 414 |
}
|
| 415 |
}
|
| 416 |
free(omega_iarr); free(omega_oarr);
|
| 417 |
return(1);
|
| 418 |
}
|
| 419 |
|
| 420 |
struct BSDF_data *
|
| 421 |
load_BSDF( /* load BSDF data from file */
|
| 422 |
char *fname
|
| 423 |
)
|
| 424 |
{
|
| 425 |
char *path;
|
| 426 |
ezxml_t fl, wtl, wld, wdb;
|
| 427 |
struct BSDF_data *dp;
|
| 428 |
|
| 429 |
path = getpath(fname, getrlibpath(), R_OK);
|
| 430 |
if (path == NULL) {
|
| 431 |
sprintf(errmsg, "cannot find BSDF file \"%s\"", fname);
|
| 432 |
error(WARNING, errmsg);
|
| 433 |
return(NULL);
|
| 434 |
}
|
| 435 |
fl = ezxml_parse_file(path);
|
| 436 |
if (fl == NULL) {
|
| 437 |
sprintf(errmsg, "cannot open BSDF \"%s\"", path);
|
| 438 |
error(WARNING, errmsg);
|
| 439 |
return(NULL);
|
| 440 |
}
|
| 441 |
if (ezxml_error(fl)[0]) {
|
| 442 |
sprintf(errmsg, "BSDF \"%s\" %s", path, ezxml_error(fl));
|
| 443 |
error(WARNING, errmsg);
|
| 444 |
ezxml_free(fl);
|
| 445 |
return(NULL);
|
| 446 |
}
|
| 447 |
if (strcmp(ezxml_name(fl), "WindowElement")) {
|
| 448 |
sprintf(errmsg,
|
| 449 |
"BSDF \"%s\": top level node not 'WindowElement'",
|
| 450 |
path);
|
| 451 |
error(WARNING, errmsg);
|
| 452 |
ezxml_free(fl);
|
| 453 |
return(NULL);
|
| 454 |
}
|
| 455 |
wtl = ezxml_child(ezxml_child(fl, "Optical"), "Layer");
|
| 456 |
load_angle_basis(ezxml_child(ezxml_child(wtl,
|
| 457 |
"DataDefinition"), "AngleBasis"));
|
| 458 |
dp = (struct BSDF_data *)calloc(1, sizeof(struct BSDF_data));
|
| 459 |
for (wld = ezxml_child(wtl, "WavelengthData");
|
| 460 |
wld != NULL; wld = wld->next) {
|
| 461 |
if (strcmp(ezxml_txt(ezxml_child(wld,"Wavelength")), "Visible"))
|
| 462 |
continue;
|
| 463 |
wdb = ezxml_child(wld, "WavelengthDataBlock");
|
| 464 |
if (wdb == NULL) continue;
|
| 465 |
if (strcmp(ezxml_txt(ezxml_child(wdb,"WavelengthDataDirection")),
|
| 466 |
"Transmission Front"))
|
| 467 |
continue;
|
| 468 |
load_bsdf_data(dp, wdb); /* load front BTDF */
|
| 469 |
break; /* ignore the rest */
|
| 470 |
}
|
| 471 |
ezxml_free(fl); /* done with XML file */
|
| 472 |
if (!check_bsdf_data(dp)) {
|
| 473 |
sprintf(errmsg, "bad/missing BTDF data in \"%s\"", path);
|
| 474 |
error(WARNING, errmsg);
|
| 475 |
free_BSDF(dp);
|
| 476 |
dp = NULL;
|
| 477 |
}
|
| 478 |
return(dp);
|
| 479 |
}
|
| 480 |
|
| 481 |
|
| 482 |
void
|
| 483 |
free_BSDF( /* free BSDF data structure */
|
| 484 |
struct BSDF_data *b
|
| 485 |
)
|
| 486 |
{
|
| 487 |
if (b == NULL)
|
| 488 |
return;
|
| 489 |
if (b->bsdf != NULL)
|
| 490 |
free(b->bsdf);
|
| 491 |
free(b);
|
| 492 |
}
|
| 493 |
|
| 494 |
|
| 495 |
int
|
| 496 |
r_BSDF_incvec( /* compute random input vector at given location */
|
| 497 |
FVECT v,
|
| 498 |
struct BSDF_data *b,
|
| 499 |
int i,
|
| 500 |
double rv,
|
| 501 |
MAT4 xm
|
| 502 |
)
|
| 503 |
{
|
| 504 |
FVECT pert;
|
| 505 |
double rad;
|
| 506 |
int j;
|
| 507 |
|
| 508 |
if (!getBSDF_incvec(v, b, i))
|
| 509 |
return(0);
|
| 510 |
rad = sqrt(getBSDF_incohm(b, i) / PI);
|
| 511 |
multisamp(pert, 3, rv);
|
| 512 |
for (j = 0; j < 3; j++)
|
| 513 |
v[j] += rad*(2.*pert[j] - 1.);
|
| 514 |
if (xm != NULL)
|
| 515 |
multv3(v, v, xm);
|
| 516 |
return(normalize(v) != 0.0);
|
| 517 |
}
|
| 518 |
|
| 519 |
|
| 520 |
int
|
| 521 |
r_BSDF_outvec( /* compute random output vector at given location */
|
| 522 |
FVECT v,
|
| 523 |
struct BSDF_data *b,
|
| 524 |
int o,
|
| 525 |
double rv,
|
| 526 |
MAT4 xm
|
| 527 |
)
|
| 528 |
{
|
| 529 |
FVECT pert;
|
| 530 |
double rad;
|
| 531 |
int j;
|
| 532 |
|
| 533 |
if (!getBSDF_outvec(v, b, o))
|
| 534 |
return(0);
|
| 535 |
rad = sqrt(getBSDF_outohm(b, o) / PI);
|
| 536 |
multisamp(pert, 3, rv);
|
| 537 |
for (j = 0; j < 3; j++)
|
| 538 |
v[j] += rad*(2.*pert[j] - 1.);
|
| 539 |
if (xm != NULL)
|
| 540 |
multv3(v, v, xm);
|
| 541 |
return(normalize(v) != 0.0);
|
| 542 |
}
|
| 543 |
|
| 544 |
|
| 545 |
static int
|
| 546 |
addrot( /* compute rotation (x,y,z) => (xp,yp,zp) */
|
| 547 |
char *xfarg[],
|
| 548 |
FVECT xp,
|
| 549 |
FVECT yp,
|
| 550 |
FVECT zp
|
| 551 |
)
|
| 552 |
{
|
| 553 |
static char bufs[3][16];
|
| 554 |
int bn = 0;
|
| 555 |
char **xfp = xfarg;
|
| 556 |
double theta;
|
| 557 |
|
| 558 |
if (yp[2]*yp[2] + zp[2]*zp[2] < 2.*FTINY*FTINY) {
|
| 559 |
/* Special case for X' along Z-axis */
|
| 560 |
theta = -atan2(yp[0], yp[1]);
|
| 561 |
*xfp++ = "-ry";
|
| 562 |
*xfp++ = xp[2] < 0.0 ? "90" : "-90";
|
| 563 |
*xfp++ = "-rz";
|
| 564 |
sprintf(bufs[bn], "%f", theta*(180./PI));
|
| 565 |
*xfp++ = bufs[bn++];
|
| 566 |
return(xfp - xfarg);
|
| 567 |
}
|
| 568 |
theta = atan2(yp[2], zp[2]);
|
| 569 |
if (!FEQ(theta,0.0)) {
|
| 570 |
*xfp++ = "-rx";
|
| 571 |
sprintf(bufs[bn], "%f", theta*(180./PI));
|
| 572 |
*xfp++ = bufs[bn++];
|
| 573 |
}
|
| 574 |
theta = asin(-xp[2]);
|
| 575 |
if (!FEQ(theta,0.0)) {
|
| 576 |
*xfp++ = "-ry";
|
| 577 |
sprintf(bufs[bn], " %f", theta*(180./PI));
|
| 578 |
*xfp++ = bufs[bn++];
|
| 579 |
}
|
| 580 |
theta = atan2(xp[1], xp[0]);
|
| 581 |
if (!FEQ(theta,0.0)) {
|
| 582 |
*xfp++ = "-rz";
|
| 583 |
sprintf(bufs[bn], "%f", theta*(180./PI));
|
| 584 |
*xfp++ = bufs[bn++];
|
| 585 |
}
|
| 586 |
*xfp = NULL;
|
| 587 |
return(xfp - xfarg);
|
| 588 |
}
|
| 589 |
|
| 590 |
|
| 591 |
int
|
| 592 |
getBSDF_xfm( /* compute BSDF orient. -> world orient. transform */
|
| 593 |
MAT4 xm,
|
| 594 |
FVECT nrm,
|
| 595 |
UpDir ud
|
| 596 |
)
|
| 597 |
{
|
| 598 |
char *xfargs[7];
|
| 599 |
XF myxf;
|
| 600 |
FVECT updir, xdest, ydest;
|
| 601 |
|
| 602 |
updir[0] = updir[1] = updir[2] = 0.;
|
| 603 |
switch (ud) {
|
| 604 |
case UDzneg:
|
| 605 |
updir[2] = -1.;
|
| 606 |
break;
|
| 607 |
case UDyneg:
|
| 608 |
updir[1] = -1.;
|
| 609 |
break;
|
| 610 |
case UDxneg:
|
| 611 |
updir[0] = -1.;
|
| 612 |
break;
|
| 613 |
case UDxpos:
|
| 614 |
updir[0] = 1.;
|
| 615 |
break;
|
| 616 |
case UDypos:
|
| 617 |
updir[1] = 1.;
|
| 618 |
break;
|
| 619 |
case UDzpos:
|
| 620 |
updir[2] = 1.;
|
| 621 |
break;
|
| 622 |
case UDunknown:
|
| 623 |
return(0);
|
| 624 |
}
|
| 625 |
fcross(xdest, updir, nrm);
|
| 626 |
if (normalize(xdest) == 0.0)
|
| 627 |
return(0);
|
| 628 |
fcross(ydest, nrm, xdest);
|
| 629 |
xf(&myxf, addrot(xfargs, xdest, ydest, nrm), xfargs);
|
| 630 |
copymat4(xm, myxf.xfm);
|
| 631 |
return(1);
|
| 632 |
}
|
