| 1 |
greg |
2.1 |
#ifndef lint
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| 2 |
greg |
2.8 |
static const char RCSid[] = "$Id: m_bsdf.c,v 2.7 2011/02/22 05:41:02 greg Exp $";
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| 3 |
greg |
2.1 |
#endif
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| 4 |
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/*
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| 5 |
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* Shading for materials with BSDFs taken from XML data files
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*/
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#include "copyright.h"
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| 9 |
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| 10 |
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#include "ray.h"
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| 11 |
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#include "ambient.h"
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#include "source.h"
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| 13 |
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#include "func.h"
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| 14 |
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#include "bsdf.h"
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| 15 |
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#include "random.h"
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| 17 |
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/*
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| 18 |
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* Arguments to this material include optional diffuse colors.
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| 19 |
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* String arguments include the BSDF and function files.
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| 20 |
greg |
2.5 |
* A non-zero thickness causes the strange but useful behavior
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| 21 |
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* of translating transmitted rays this distance beneath the surface
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* (opposite the surface normal) to bypass any intervening geometry.
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* Translation only affects scattered, non-source-directed samples.
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| 24 |
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* A non-zero thickness has the further side-effect that an unscattered
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| 25 |
greg |
2.1 |
* (view) ray will pass right through our material if it has any
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| 26 |
greg |
2.5 |
* non-diffuse transmission, making the BSDF surface invisible. This
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| 27 |
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* shows the proxied geometry instead. Thickness has the further
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| 28 |
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* effect of turning off reflection on the hidden side so that rays
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* heading in the opposite direction pass unimpeded through the BSDF
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* surface. A paired surface may be placed on the opposide side of
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* the detail geometry, less than this thickness away, if a two-way
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| 32 |
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* proxy is desired. Note that the sign of the thickness is important.
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* A positive thickness hides geometry behind the BSDF surface and uses
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* front reflectance and transmission properties. A negative thickness
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* hides geometry in front of the surface when rays hit from behind,
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| 36 |
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* and applies only the transmission and backside reflectance properties.
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* Reflection is ignored on the hidden side, as those rays pass through.
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greg |
2.1 |
* The "up" vector for the BSDF is given by three variables, defined
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| 39 |
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* (along with the thickness) by the named function file, or '.' if none.
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| 40 |
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* Together with the surface normal, this defines the local coordinate
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| 41 |
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* system for the BSDF.
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* We do not reorient the surface, so if the BSDF has no back-side
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| 43 |
greg |
2.5 |
* reflectance and none is given in the real arguments, a BSDF surface
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| 44 |
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* with zero thickness will appear black when viewed from behind
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* unless backface visibility is off.
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* The diffuse arguments are added to components in the BSDF file,
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greg |
2.1 |
* not multiplied. However, patterns affect this material as a multiplier
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* on everything except non-diffuse reflection.
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*
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* Arguments for MAT_BSDF are:
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* 6+ thick BSDFfile ux uy uz funcfile transform
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* 0
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greg |
2.8 |
* 0|3|6|9 rdf gdf bdf
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greg |
2.1 |
* rdb gdb bdb
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* rdt gdt bdt
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*/
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greg |
2.4 |
/*
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* Note that our reverse ray-tracing process means that the positions
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* of incoming and outgoing vectors may be reversed in our calls
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* to the BSDF library. This is fine, since the bidirectional nature
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* of the BSDF (that's what the 'B' stands for) means it all works out.
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*/
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greg |
2.1 |
typedef struct {
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OBJREC *mp; /* material pointer */
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RAY *pr; /* intersected ray */
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FVECT pnorm; /* perturbed surface normal */
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greg |
2.4 |
FVECT vray; /* local outgoing (return) vector */
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double sr_vpsa; /* sqrt of BSDF projected solid angle */
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greg |
2.1 |
RREAL toloc[3][3]; /* world to local BSDF coords */
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RREAL fromloc[3][3]; /* local BSDF coords to world */
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double thick; /* surface thickness */
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SDData *sd; /* loaded BSDF data */
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COLOR runsamp; /* BSDF hemispherical reflection */
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COLOR rdiff; /* added diffuse reflection */
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COLOR tunsamp; /* BSDF hemispherical transmission */
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COLOR tdiff; /* added diffuse transmission */
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} BSDFDAT; /* BSDF material data */
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#define cvt_sdcolor(cv, svp) ccy2rgb(&(svp)->spec, (svp)->cieY, cv)
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greg |
2.4 |
/* Jitter ray sample according to projected solid angle and specjitter */
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static void
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bsdf_jitter(FVECT vres, BSDFDAT *ndp)
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{
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| 87 |
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double sr_psa = ndp->sr_vpsa;
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VCOPY(vres, ndp->vray);
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| 90 |
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if (specjitter < 1.)
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sr_psa *= specjitter;
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if (sr_psa <= FTINY)
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| 93 |
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return;
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| 94 |
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vres[0] += sr_psa*(.5 - frandom());
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vres[1] += sr_psa*(.5 - frandom());
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normalize(vres);
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| 97 |
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}
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greg |
2.7 |
/* Evaluate BSDF for direct component, returning true if OK to proceed */
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static int
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direct_bsdf_OK(COLOR cval, FVECT ldir, BSDFDAT *ndp)
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{
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| 103 |
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FVECT vsrc, vjit;
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| 104 |
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SDValue sv;
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| 105 |
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SDError ec;
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| 106 |
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/* transform source direction */
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| 107 |
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if (SDmapDir(vsrc, ndp->toloc, ldir) != SDEnone)
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| 108 |
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return(0);
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| 109 |
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/* jitter query direction */
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bsdf_jitter(vjit, ndp);
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| 111 |
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/* avoid indirect over-counting */
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if (ndp->thick != .0 && ndp->pr->crtype & (SPECULAR|AMBIENT) &&
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vsrc[2] > .0 ^ vjit[2] > .0) {
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double dx = vsrc[0] + vjit[0];
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| 115 |
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double dy = vsrc[1] + vjit[1];
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| 116 |
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if (dx*dx + dy*dy <= ndp->sr_vpsa*ndp->sr_vpsa)
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| 117 |
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return(0);
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| 118 |
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}
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| 119 |
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ec = SDevalBSDF(&sv, vjit, vsrc, ndp->sd);
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| 120 |
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if (ec)
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| 121 |
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objerror(ndp->mp, USER, transSDError(ec));
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| 122 |
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| 123 |
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if (sv.cieY <= FTINY) /* not worth using? */
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| 124 |
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return(0);
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| 125 |
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/* else we're good to go */
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| 126 |
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cvt_sdcolor(cval, &sv);
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| 127 |
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return(1);
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| 128 |
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}
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| 129 |
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| 130 |
greg |
2.5 |
/* Compute source contribution for BSDF (reflected & transmitted) */
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| 131 |
greg |
2.1 |
static void
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| 132 |
greg |
2.5 |
dir_bsdf(
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| 133 |
greg |
2.1 |
COLOR cval, /* returned coefficient */
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| 134 |
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void *nnp, /* material data */
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| 135 |
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FVECT ldir, /* light source direction */
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| 136 |
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double omega /* light source size */
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| 137 |
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)
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| 138 |
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{
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| 139 |
greg |
2.3 |
BSDFDAT *np = (BSDFDAT *)nnp;
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| 140 |
greg |
2.1 |
double ldot;
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| 141 |
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double dtmp;
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| 142 |
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COLOR ctmp;
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| 143 |
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| 144 |
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setcolor(cval, .0, .0, .0);
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| 145 |
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| 146 |
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ldot = DOT(np->pnorm, ldir);
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| 147 |
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if ((-FTINY <= ldot) & (ldot <= FTINY))
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| 148 |
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return;
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| 149 |
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| 150 |
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if (ldot > .0 && bright(np->rdiff) > FTINY) {
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| 151 |
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/*
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| 152 |
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* Compute added diffuse reflected component.
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| 153 |
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*/
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| 154 |
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copycolor(ctmp, np->rdiff);
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| 155 |
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dtmp = ldot * omega * (1./PI);
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| 156 |
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scalecolor(ctmp, dtmp);
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| 157 |
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addcolor(cval, ctmp);
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| 158 |
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}
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| 159 |
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if (ldot < .0 && bright(np->tdiff) > FTINY) {
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| 160 |
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/*
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| 161 |
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* Compute added diffuse transmission.
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| 162 |
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*/
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| 163 |
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copycolor(ctmp, np->tdiff);
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| 164 |
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dtmp = -ldot * omega * (1.0/PI);
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| 165 |
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scalecolor(ctmp, dtmp);
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| 166 |
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addcolor(cval, ctmp);
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| 167 |
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}
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| 168 |
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/*
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| 169 |
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* Compute scattering coefficient using BSDF.
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| 170 |
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*/
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| 171 |
greg |
2.7 |
if (!direct_bsdf_OK(ctmp, ldir, np))
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| 172 |
greg |
2.1 |
return;
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| 173 |
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if (ldot > .0) { /* pattern only diffuse reflection */
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| 174 |
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COLOR ctmp1, ctmp2;
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| 175 |
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dtmp = (np->pr->rod > .0) ? np->sd->rLambFront.cieY
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| 176 |
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: np->sd->rLambBack.cieY;
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| 177 |
greg |
2.7 |
/* diffuse fraction */
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| 178 |
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dtmp /= PI * bright(ctmp);
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| 179 |
greg |
2.1 |
copycolor(ctmp2, np->pr->pcol);
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| 180 |
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scalecolor(ctmp2, dtmp);
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| 181 |
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setcolor(ctmp1, 1.-dtmp, 1.-dtmp, 1.-dtmp);
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| 182 |
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addcolor(ctmp1, ctmp2);
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| 183 |
greg |
2.3 |
multcolor(ctmp, ctmp1); /* apply derated pattern */
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| 184 |
greg |
2.1 |
dtmp = ldot * omega;
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| 185 |
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} else { /* full pattern on transmission */
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| 186 |
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multcolor(ctmp, np->pr->pcol);
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| 187 |
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dtmp = -ldot * omega;
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| 188 |
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}
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| 189 |
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scalecolor(ctmp, dtmp);
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| 190 |
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addcolor(cval, ctmp);
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| 191 |
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}
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| 192 |
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| 193 |
greg |
2.5 |
/* Compute source contribution for BSDF (reflected only) */
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| 194 |
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static void
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| 195 |
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dir_brdf(
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| 196 |
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COLOR cval, /* returned coefficient */
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| 197 |
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void *nnp, /* material data */
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| 198 |
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FVECT ldir, /* light source direction */
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| 199 |
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double omega /* light source size */
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| 200 |
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)
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| 201 |
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{
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| 202 |
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BSDFDAT *np = (BSDFDAT *)nnp;
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| 203 |
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double ldot;
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| 204 |
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double dtmp;
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| 205 |
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COLOR ctmp, ctmp1, ctmp2;
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| 206 |
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| 207 |
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setcolor(cval, .0, .0, .0);
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| 208 |
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| 209 |
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ldot = DOT(np->pnorm, ldir);
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| 210 |
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| 211 |
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if (ldot <= FTINY)
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| 212 |
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return;
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| 213 |
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| 214 |
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if (bright(np->rdiff) > FTINY) {
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| 215 |
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/*
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| 216 |
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* Compute added diffuse reflected component.
|
| 217 |
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*/
|
| 218 |
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copycolor(ctmp, np->rdiff);
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| 219 |
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dtmp = ldot * omega * (1./PI);
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| 220 |
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scalecolor(ctmp, dtmp);
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| 221 |
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addcolor(cval, ctmp);
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| 222 |
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}
|
| 223 |
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/*
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| 224 |
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* Compute reflection coefficient using BSDF.
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| 225 |
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*/
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| 226 |
greg |
2.7 |
if (!direct_bsdf_OK(ctmp, ldir, np))
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| 227 |
greg |
2.5 |
return;
|
| 228 |
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/* pattern only diffuse reflection */
|
| 229 |
|
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dtmp = (np->pr->rod > .0) ? np->sd->rLambFront.cieY
|
| 230 |
|
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: np->sd->rLambBack.cieY;
|
| 231 |
greg |
2.7 |
dtmp /= PI * bright(ctmp); /* diffuse fraction */
|
| 232 |
greg |
2.5 |
copycolor(ctmp2, np->pr->pcol);
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| 233 |
|
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scalecolor(ctmp2, dtmp);
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| 234 |
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setcolor(ctmp1, 1.-dtmp, 1.-dtmp, 1.-dtmp);
|
| 235 |
|
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addcolor(ctmp1, ctmp2);
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| 236 |
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multcolor(ctmp, ctmp1); /* apply derated pattern */
|
| 237 |
|
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dtmp = ldot * omega;
|
| 238 |
|
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scalecolor(ctmp, dtmp);
|
| 239 |
|
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addcolor(cval, ctmp);
|
| 240 |
|
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}
|
| 241 |
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|
| 242 |
|
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/* Compute source contribution for BSDF (transmitted only) */
|
| 243 |
|
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static void
|
| 244 |
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dir_btdf(
|
| 245 |
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COLOR cval, /* returned coefficient */
|
| 246 |
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void *nnp, /* material data */
|
| 247 |
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FVECT ldir, /* light source direction */
|
| 248 |
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double omega /* light source size */
|
| 249 |
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)
|
| 250 |
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{
|
| 251 |
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BSDFDAT *np = (BSDFDAT *)nnp;
|
| 252 |
|
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double ldot;
|
| 253 |
|
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double dtmp;
|
| 254 |
|
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COLOR ctmp;
|
| 255 |
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|
| 256 |
|
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setcolor(cval, .0, .0, .0);
|
| 257 |
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|
| 258 |
|
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ldot = DOT(np->pnorm, ldir);
|
| 259 |
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|
| 260 |
|
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if (ldot >= -FTINY)
|
| 261 |
|
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return;
|
| 262 |
|
|
|
| 263 |
|
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if (bright(np->tdiff) > FTINY) {
|
| 264 |
|
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/*
|
| 265 |
|
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* Compute added diffuse transmission.
|
| 266 |
|
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*/
|
| 267 |
|
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copycolor(ctmp, np->tdiff);
|
| 268 |
|
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dtmp = -ldot * omega * (1.0/PI);
|
| 269 |
|
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scalecolor(ctmp, dtmp);
|
| 270 |
|
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addcolor(cval, ctmp);
|
| 271 |
|
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}
|
| 272 |
|
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/*
|
| 273 |
|
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* Compute scattering coefficient using BSDF.
|
| 274 |
|
|
*/
|
| 275 |
greg |
2.7 |
if (!direct_bsdf_OK(ctmp, ldir, np))
|
| 276 |
greg |
2.5 |
return;
|
| 277 |
|
|
/* full pattern on transmission */
|
| 278 |
|
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multcolor(ctmp, np->pr->pcol);
|
| 279 |
|
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dtmp = -ldot * omega;
|
| 280 |
|
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scalecolor(ctmp, dtmp);
|
| 281 |
|
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addcolor(cval, ctmp);
|
| 282 |
|
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}
|
| 283 |
|
|
|
| 284 |
greg |
2.1 |
/* Sample separate BSDF component */
|
| 285 |
|
|
static int
|
| 286 |
|
|
sample_sdcomp(BSDFDAT *ndp, SDComponent *dcp, int usepat)
|
| 287 |
|
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{
|
| 288 |
|
|
int nstarget = 1;
|
| 289 |
|
|
int nsent = 0;
|
| 290 |
|
|
SDError ec;
|
| 291 |
|
|
SDValue bsv;
|
| 292 |
|
|
double sthick;
|
| 293 |
greg |
2.4 |
FVECT vjit, vsmp;
|
| 294 |
greg |
2.1 |
RAY sr;
|
| 295 |
|
|
int ntrials;
|
| 296 |
|
|
/* multiple samples? */
|
| 297 |
|
|
if (specjitter > 1.5) {
|
| 298 |
|
|
nstarget = specjitter*ndp->pr->rweight + .5;
|
| 299 |
|
|
if (nstarget < 1)
|
| 300 |
|
|
nstarget = 1;
|
| 301 |
|
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}
|
| 302 |
|
|
/* run through our trials */
|
| 303 |
|
|
for (ntrials = 0; nsent < nstarget && ntrials < 9*nstarget; ntrials++) {
|
| 304 |
|
|
SDerrorDetail[0] = '\0';
|
| 305 |
|
|
/* sample direction & coef. */
|
| 306 |
greg |
2.4 |
bsdf_jitter(vjit, ndp);
|
| 307 |
|
|
ec = SDsampComponent(&bsv, vsmp, vjit, ntrials ? frandom()
|
| 308 |
|
|
: urand(ilhash(dimlist,ndims)+samplendx), dcp);
|
| 309 |
greg |
2.1 |
if (ec)
|
| 310 |
greg |
2.2 |
objerror(ndp->mp, USER, transSDError(ec));
|
| 311 |
greg |
2.1 |
/* zero component? */
|
| 312 |
|
|
if (bsv.cieY <= FTINY)
|
| 313 |
|
|
break;
|
| 314 |
|
|
/* map vector to world */
|
| 315 |
greg |
2.4 |
if (SDmapDir(sr.rdir, ndp->fromloc, vsmp) != SDEnone)
|
| 316 |
greg |
2.1 |
break;
|
| 317 |
|
|
/* unintentional penetration? */
|
| 318 |
greg |
2.4 |
if (DOT(sr.rdir, ndp->pr->ron) > .0 ^ vsmp[2] > .0)
|
| 319 |
greg |
2.1 |
continue;
|
| 320 |
|
|
/* spawn a specular ray */
|
| 321 |
|
|
if (nstarget > 1)
|
| 322 |
|
|
bsv.cieY /= (double)nstarget;
|
| 323 |
|
|
cvt_sdcolor(sr.rcoef, &bsv); /* use color */
|
| 324 |
|
|
if (usepat) /* pattern on transmission */
|
| 325 |
|
|
multcolor(sr.rcoef, ndp->pr->pcol);
|
| 326 |
|
|
if (rayorigin(&sr, SPECULAR, ndp->pr, sr.rcoef) < 0) {
|
| 327 |
|
|
if (maxdepth > 0)
|
| 328 |
|
|
break;
|
| 329 |
|
|
++nsent; /* Russian roulette victim */
|
| 330 |
|
|
continue;
|
| 331 |
|
|
}
|
| 332 |
greg |
2.5 |
/* need to offset origin? */
|
| 333 |
|
|
if (ndp->thick != .0 && ndp->pr->rod > .0 ^ vsmp[2] > .0)
|
| 334 |
|
|
VSUM(sr.rorg, sr.rorg, ndp->pr->ron, -ndp->thick);
|
| 335 |
greg |
2.1 |
rayvalue(&sr); /* send & evaluate sample */
|
| 336 |
|
|
multcolor(sr.rcol, sr.rcoef);
|
| 337 |
|
|
addcolor(ndp->pr->rcol, sr.rcol);
|
| 338 |
|
|
++nsent;
|
| 339 |
|
|
}
|
| 340 |
|
|
return(nsent);
|
| 341 |
|
|
}
|
| 342 |
|
|
|
| 343 |
|
|
/* Sample non-diffuse components of BSDF */
|
| 344 |
|
|
static int
|
| 345 |
|
|
sample_sdf(BSDFDAT *ndp, int sflags)
|
| 346 |
|
|
{
|
| 347 |
|
|
int n, ntotal = 0;
|
| 348 |
|
|
SDSpectralDF *dfp;
|
| 349 |
|
|
COLORV *unsc;
|
| 350 |
|
|
|
| 351 |
|
|
if (sflags == SDsampSpT) {
|
| 352 |
|
|
unsc = ndp->tunsamp;
|
| 353 |
|
|
dfp = ndp->sd->tf;
|
| 354 |
|
|
cvt_sdcolor(unsc, &ndp->sd->tLamb);
|
| 355 |
|
|
} else /* sflags == SDsampSpR */ {
|
| 356 |
|
|
unsc = ndp->runsamp;
|
| 357 |
|
|
if (ndp->pr->rod > .0) {
|
| 358 |
|
|
dfp = ndp->sd->rf;
|
| 359 |
|
|
cvt_sdcolor(unsc, &ndp->sd->rLambFront);
|
| 360 |
|
|
} else {
|
| 361 |
|
|
dfp = ndp->sd->rb;
|
| 362 |
|
|
cvt_sdcolor(unsc, &ndp->sd->rLambBack);
|
| 363 |
|
|
}
|
| 364 |
|
|
}
|
| 365 |
|
|
multcolor(unsc, ndp->pr->pcol);
|
| 366 |
|
|
if (dfp == NULL) /* no specular component? */
|
| 367 |
|
|
return(0);
|
| 368 |
|
|
/* below sampling threshold? */
|
| 369 |
|
|
if (dfp->maxHemi <= specthresh+FTINY) {
|
| 370 |
greg |
2.3 |
if (dfp->maxHemi > FTINY) { /* XXX no color from BSDF */
|
| 371 |
greg |
2.4 |
FVECT vjit;
|
| 372 |
|
|
double d;
|
| 373 |
greg |
2.1 |
COLOR ctmp;
|
| 374 |
greg |
2.4 |
bsdf_jitter(vjit, ndp);
|
| 375 |
|
|
d = SDdirectHemi(vjit, sflags, ndp->sd);
|
| 376 |
greg |
2.1 |
if (sflags == SDsampSpT) {
|
| 377 |
|
|
copycolor(ctmp, ndp->pr->pcol);
|
| 378 |
|
|
scalecolor(ctmp, d);
|
| 379 |
|
|
} else /* no pattern on reflection */
|
| 380 |
|
|
setcolor(ctmp, d, d, d);
|
| 381 |
|
|
addcolor(unsc, ctmp);
|
| 382 |
|
|
}
|
| 383 |
|
|
return(0);
|
| 384 |
|
|
}
|
| 385 |
|
|
/* else need to sample */
|
| 386 |
|
|
dimlist[ndims++] = (int)(size_t)ndp->mp;
|
| 387 |
|
|
ndims++;
|
| 388 |
|
|
for (n = dfp->ncomp; n--; ) { /* loop over components */
|
| 389 |
|
|
dimlist[ndims-1] = n + 9438;
|
| 390 |
|
|
ntotal += sample_sdcomp(ndp, &dfp->comp[n], sflags==SDsampSpT);
|
| 391 |
|
|
}
|
| 392 |
|
|
ndims -= 2;
|
| 393 |
|
|
return(ntotal);
|
| 394 |
|
|
}
|
| 395 |
|
|
|
| 396 |
|
|
/* Color a ray that hit a BSDF material */
|
| 397 |
|
|
int
|
| 398 |
|
|
m_bsdf(OBJREC *m, RAY *r)
|
| 399 |
|
|
{
|
| 400 |
greg |
2.6 |
int hitfront;
|
| 401 |
greg |
2.1 |
COLOR ctmp;
|
| 402 |
|
|
SDError ec;
|
| 403 |
greg |
2.5 |
FVECT upvec, vtmp;
|
| 404 |
greg |
2.1 |
MFUNC *mf;
|
| 405 |
|
|
BSDFDAT nd;
|
| 406 |
|
|
/* check arguments */
|
| 407 |
|
|
if ((m->oargs.nsargs < 6) | (m->oargs.nfargs > 9) |
|
| 408 |
|
|
(m->oargs.nfargs % 3))
|
| 409 |
|
|
objerror(m, USER, "bad # arguments");
|
| 410 |
greg |
2.6 |
/* record surface struck */
|
| 411 |
|
|
hitfront = (r->rod > .0);
|
| 412 |
greg |
2.1 |
/* load cal file */
|
| 413 |
|
|
mf = getfunc(m, 5, 0x1d, 1);
|
| 414 |
|
|
/* get thickness */
|
| 415 |
|
|
nd.thick = evalue(mf->ep[0]);
|
| 416 |
greg |
2.5 |
if ((-FTINY <= nd.thick) & (nd.thick <= FTINY))
|
| 417 |
greg |
2.1 |
nd.thick = .0;
|
| 418 |
|
|
/* check shadow */
|
| 419 |
|
|
if (r->crtype & SHADOW) {
|
| 420 |
greg |
2.5 |
if (nd.thick != .0)
|
| 421 |
greg |
2.3 |
raytrans(r); /* pass-through */
|
| 422 |
greg |
2.5 |
return(1); /* or shadow */
|
| 423 |
greg |
2.1 |
}
|
| 424 |
greg |
2.5 |
/* check other rays to pass */
|
| 425 |
greg |
2.7 |
if (nd.thick != .0 && (!(r->crtype & (SPECULAR|AMBIENT)) ||
|
| 426 |
greg |
2.6 |
nd.thick > .0 ^ hitfront)) {
|
| 427 |
greg |
2.5 |
raytrans(r); /* hide our proxy */
|
| 428 |
greg |
2.1 |
return(1);
|
| 429 |
|
|
}
|
| 430 |
greg |
2.5 |
/* get BSDF data */
|
| 431 |
|
|
nd.sd = loadBSDF(m->oargs.sarg[1]);
|
| 432 |
greg |
2.1 |
/* diffuse reflectance */
|
| 433 |
greg |
2.6 |
if (hitfront) {
|
| 434 |
greg |
2.1 |
if (m->oargs.nfargs < 3)
|
| 435 |
|
|
setcolor(nd.rdiff, .0, .0, .0);
|
| 436 |
|
|
else
|
| 437 |
|
|
setcolor(nd.rdiff, m->oargs.farg[0],
|
| 438 |
|
|
m->oargs.farg[1],
|
| 439 |
|
|
m->oargs.farg[2]);
|
| 440 |
|
|
} else {
|
| 441 |
|
|
if (m->oargs.nfargs < 6) { /* check invisible backside */
|
| 442 |
greg |
2.3 |
if (!backvis && (nd.sd->rb == NULL) &
|
| 443 |
|
|
(nd.sd->tf == NULL)) {
|
| 444 |
greg |
2.1 |
SDfreeCache(nd.sd);
|
| 445 |
|
|
raytrans(r);
|
| 446 |
|
|
return(1);
|
| 447 |
|
|
}
|
| 448 |
|
|
setcolor(nd.rdiff, .0, .0, .0);
|
| 449 |
|
|
} else
|
| 450 |
|
|
setcolor(nd.rdiff, m->oargs.farg[3],
|
| 451 |
|
|
m->oargs.farg[4],
|
| 452 |
|
|
m->oargs.farg[5]);
|
| 453 |
|
|
}
|
| 454 |
|
|
/* diffuse transmittance */
|
| 455 |
|
|
if (m->oargs.nfargs < 9)
|
| 456 |
|
|
setcolor(nd.tdiff, .0, .0, .0);
|
| 457 |
|
|
else
|
| 458 |
|
|
setcolor(nd.tdiff, m->oargs.farg[6],
|
| 459 |
|
|
m->oargs.farg[7],
|
| 460 |
|
|
m->oargs.farg[8]);
|
| 461 |
|
|
nd.mp = m;
|
| 462 |
|
|
nd.pr = r;
|
| 463 |
|
|
/* get modifiers */
|
| 464 |
|
|
raytexture(r, m->omod);
|
| 465 |
|
|
/* modify diffuse values */
|
| 466 |
|
|
multcolor(nd.rdiff, r->pcol);
|
| 467 |
|
|
multcolor(nd.tdiff, r->pcol);
|
| 468 |
|
|
/* get up vector */
|
| 469 |
|
|
upvec[0] = evalue(mf->ep[1]);
|
| 470 |
|
|
upvec[1] = evalue(mf->ep[2]);
|
| 471 |
|
|
upvec[2] = evalue(mf->ep[3]);
|
| 472 |
|
|
/* return to world coords */
|
| 473 |
|
|
if (mf->f != &unitxf) {
|
| 474 |
|
|
multv3(upvec, upvec, mf->f->xfm);
|
| 475 |
|
|
nd.thick *= mf->f->sca;
|
| 476 |
|
|
}
|
| 477 |
|
|
raynormal(nd.pnorm, r);
|
| 478 |
|
|
/* compute local BSDF xform */
|
| 479 |
|
|
ec = SDcompXform(nd.toloc, nd.pnorm, upvec);
|
| 480 |
|
|
if (!ec) {
|
| 481 |
greg |
2.4 |
nd.vray[0] = -r->rdir[0];
|
| 482 |
|
|
nd.vray[1] = -r->rdir[1];
|
| 483 |
|
|
nd.vray[2] = -r->rdir[2];
|
| 484 |
|
|
ec = SDmapDir(nd.vray, nd.toloc, nd.vray);
|
| 485 |
greg |
2.1 |
}
|
| 486 |
|
|
if (!ec)
|
| 487 |
|
|
ec = SDinvXform(nd.fromloc, nd.toloc);
|
| 488 |
greg |
2.4 |
/* determine BSDF resolution */
|
| 489 |
|
|
if (!ec)
|
| 490 |
|
|
ec = SDsizeBSDF(&nd.sr_vpsa, nd.vray, SDqueryMin, nd.sd);
|
| 491 |
|
|
if (!ec)
|
| 492 |
|
|
nd.sr_vpsa = sqrt(nd.sr_vpsa);
|
| 493 |
|
|
else {
|
| 494 |
greg |
2.2 |
objerror(m, WARNING, transSDError(ec));
|
| 495 |
greg |
2.1 |
SDfreeCache(nd.sd);
|
| 496 |
|
|
return(1);
|
| 497 |
|
|
}
|
| 498 |
greg |
2.6 |
if (!hitfront) { /* perturb normal towards hit */
|
| 499 |
greg |
2.1 |
nd.pnorm[0] = -nd.pnorm[0];
|
| 500 |
|
|
nd.pnorm[1] = -nd.pnorm[1];
|
| 501 |
|
|
nd.pnorm[2] = -nd.pnorm[2];
|
| 502 |
|
|
}
|
| 503 |
|
|
/* sample reflection */
|
| 504 |
|
|
sample_sdf(&nd, SDsampSpR);
|
| 505 |
|
|
/* sample transmission */
|
| 506 |
|
|
sample_sdf(&nd, SDsampSpT);
|
| 507 |
|
|
/* compute indirect diffuse */
|
| 508 |
|
|
copycolor(ctmp, nd.rdiff);
|
| 509 |
|
|
addcolor(ctmp, nd.runsamp);
|
| 510 |
greg |
2.5 |
if (bright(ctmp) > FTINY) { /* ambient from reflection */
|
| 511 |
greg |
2.6 |
if (!hitfront)
|
| 512 |
greg |
2.1 |
flipsurface(r);
|
| 513 |
|
|
multambient(ctmp, r, nd.pnorm);
|
| 514 |
|
|
addcolor(r->rcol, ctmp);
|
| 515 |
greg |
2.6 |
if (!hitfront)
|
| 516 |
greg |
2.1 |
flipsurface(r);
|
| 517 |
|
|
}
|
| 518 |
|
|
copycolor(ctmp, nd.tdiff);
|
| 519 |
|
|
addcolor(ctmp, nd.tunsamp);
|
| 520 |
|
|
if (bright(ctmp) > FTINY) { /* ambient from other side */
|
| 521 |
|
|
FVECT bnorm;
|
| 522 |
greg |
2.6 |
if (hitfront)
|
| 523 |
greg |
2.1 |
flipsurface(r);
|
| 524 |
|
|
bnorm[0] = -nd.pnorm[0];
|
| 525 |
|
|
bnorm[1] = -nd.pnorm[1];
|
| 526 |
|
|
bnorm[2] = -nd.pnorm[2];
|
| 527 |
greg |
2.5 |
if (nd.thick != .0) { /* proxy with offset? */
|
| 528 |
|
|
VCOPY(vtmp, r->rop);
|
| 529 |
|
|
VSUM(r->rop, vtmp, r->ron, -nd.thick);
|
| 530 |
|
|
multambient(ctmp, r, bnorm);
|
| 531 |
|
|
VCOPY(r->rop, vtmp);
|
| 532 |
|
|
} else
|
| 533 |
|
|
multambient(ctmp, r, bnorm);
|
| 534 |
greg |
2.1 |
addcolor(r->rcol, ctmp);
|
| 535 |
greg |
2.6 |
if (hitfront)
|
| 536 |
greg |
2.1 |
flipsurface(r);
|
| 537 |
|
|
}
|
| 538 |
|
|
/* add direct component */
|
| 539 |
greg |
2.5 |
if ((bright(nd.tdiff) <= FTINY) & (nd.sd->tf == NULL)) {
|
| 540 |
|
|
direct(r, dir_brdf, &nd); /* reflection only */
|
| 541 |
|
|
} else if (nd.thick == .0) {
|
| 542 |
|
|
direct(r, dir_bsdf, &nd); /* thin surface scattering */
|
| 543 |
|
|
} else {
|
| 544 |
|
|
direct(r, dir_brdf, &nd); /* reflection first */
|
| 545 |
|
|
VCOPY(vtmp, r->rop); /* offset for transmitted */
|
| 546 |
|
|
VSUM(r->rop, vtmp, r->ron, -nd.thick);
|
| 547 |
greg |
2.6 |
direct(r, dir_btdf, &nd); /* separate transmission */
|
| 548 |
greg |
2.5 |
VCOPY(r->rop, vtmp);
|
| 549 |
|
|
}
|
| 550 |
greg |
2.1 |
/* clean up */
|
| 551 |
|
|
SDfreeCache(nd.sd);
|
| 552 |
|
|
return(1);
|
| 553 |
|
|
}
|
