| 1 |
|
/* RCSid $Id$ */ |
| 2 |
|
/* |
| 3 |
< |
* Header for BSDF i/o and access routines |
| 3 |
> |
* bsdf.h |
| 4 |
> |
* |
| 5 |
> |
* Declarations for bidirectional scattering distribution functions. |
| 6 |
> |
* Assumes <stdio.h> already included. |
| 7 |
> |
* |
| 8 |
> |
* A material is oriented in right-hand coordinate system with X-axis |
| 9 |
> |
* in the surface plane pointed to the right as seen from the front. |
| 10 |
> |
* This means the Y-axis is "up" and the Z-axis is the surface normal. |
| 11 |
> |
* |
| 12 |
> |
* Note that we reverse the identification of "front" and "back" from |
| 13 |
> |
* the conventions used in WINDOW 6. "Front" in our library points |
| 14 |
> |
* in the +Z direction, towards the interior of the space rather |
| 15 |
> |
* than the exterior. |
| 16 |
> |
* |
| 17 |
> |
* BSDF incident & exiting vectors are always oriented away from surface. |
| 18 |
> |
* |
| 19 |
> |
* Created by Greg Ward on 1/10/11. |
| 20 |
> |
* |
| 21 |
|
*/ |
| 5 |
– |
/* up directions */ |
| 6 |
– |
typedef enum { |
| 7 |
– |
UDzneg=-3, |
| 8 |
– |
UDyneg=-2, |
| 9 |
– |
UDxneg=-1, |
| 10 |
– |
UDunknown=0, |
| 11 |
– |
UDxpos=1, |
| 12 |
– |
UDypos=2, |
| 13 |
– |
UDzpos=3 |
| 14 |
– |
} UpDir; |
| 15 |
– |
/* BSDF coordinate calculation routines */ |
| 16 |
– |
/* vectors always point away from surface */ |
| 17 |
– |
typedef int b_vecf(FVECT, int, void *); |
| 18 |
– |
typedef int b_ndxf(FVECT, void *); |
| 19 |
– |
typedef double b_radf(int, void *); |
| 22 |
|
|
| 23 |
< |
/* Bidirectional Scattering Distribution Function */ |
| 24 |
< |
struct BSDF_data { |
| 23 |
< |
int ninc; /* number of incoming directions */ |
| 24 |
< |
int nout; /* number of outgoing directions */ |
| 25 |
< |
void *ib_priv; /* input basis private data */ |
| 26 |
< |
b_vecf *ib_vec; /* get input vector from index */ |
| 27 |
< |
b_ndxf *ib_ndx; /* get input index from vector */ |
| 28 |
< |
b_radf *ib_ohm; /* get input radius for index */ |
| 29 |
< |
void *ob_priv; /* output basis private data */ |
| 30 |
< |
b_vecf *ob_vec; /* get output vector from index */ |
| 31 |
< |
b_ndxf *ob_ndx; /* get output index from vector */ |
| 32 |
< |
b_radf *ob_ohm; /* get output radius for index */ |
| 33 |
< |
float *bsdf; /* scattering distribution data */ |
| 34 |
< |
}; /* bidirectional scattering distrib. func. */ |
| 23 |
> |
#ifndef _BSDF_H_ |
| 24 |
> |
#define _BSDF_H_ |
| 25 |
|
|
| 26 |
< |
#define getBSDF_incvec(v,b,i) (*(b)->ib_vec)(v,i,(b)->ib_priv) |
| 27 |
< |
#define getBSDF_incndx(b,v) (*(b)->ib_ndx)(v,(b)->ib_priv) |
| 38 |
< |
#define getBSDF_incohm(b,i) (*(b)->ib_ohm)(i,(b)->ib_priv) |
| 39 |
< |
#define getBSDF_outvec(v,b,o) (*(b)->ob_vec)(v,o,(b)->ob_priv) |
| 40 |
< |
#define getBSDF_outndx(b,v) (*(b)->ob_ndx)(v,(b)->ob_priv) |
| 41 |
< |
#define getBSDF_outohm(b,o) (*(b)->ob_ohm)(o,(b)->ob_priv) |
| 42 |
< |
#define BSDF_value(b,i,o) (b)->bsdf[(o)*(b)->ninc + (i)] |
| 26 |
> |
#include "fvect.h" |
| 27 |
> |
#include "ccolor.h" |
| 28 |
|
|
| 29 |
< |
extern struct BSDF_data *load_BSDF(char *fname); |
| 30 |
< |
extern void free_BSDF(struct BSDF_data *b); |
| 31 |
< |
extern int r_BSDF_incvec(FVECT v, struct BSDF_data *b, int i, |
| 32 |
< |
double rv, MAT4 xm); |
| 33 |
< |
extern int r_BSDF_outvec(FVECT v, struct BSDF_data *b, int o, |
| 34 |
< |
double rv, MAT4 xm); |
| 35 |
< |
extern int getBSDF_xfm(MAT4 xm, FVECT nrm, UpDir ud); |
| 29 |
> |
#ifdef __cplusplus |
| 30 |
> |
extern "C" { |
| 31 |
> |
#endif |
| 32 |
> |
|
| 33 |
> |
#ifdef _WIN32 |
| 34 |
> |
#define strcasecmp stricmp |
| 35 |
> |
#endif |
| 36 |
> |
|
| 37 |
> |
#define SDnameLn 128 /* maximum BSDF name length */ |
| 38 |
> |
#define SDmaxCh 3 /* maximum # spectral channels */ |
| 39 |
> |
|
| 40 |
> |
/* Component flags for SDsampBSDF() and SDdirectHemi() */ |
| 41 |
> |
#define SDsampR 0x1 /* include reflection */ |
| 42 |
> |
#define SDsampT 0x2 /* include transmission */ |
| 43 |
> |
#define SDsampS 0x3 /* include scattering (R+T) */ |
| 44 |
> |
#define SDsampSp 0x4 /* include non-diffuse portion */ |
| 45 |
> |
#define SDsampDf 0x8 /* include diffuse portion */ |
| 46 |
> |
#define SDsampSpR 0x5 /* include non-diffuse reflection */ |
| 47 |
> |
#define SDsampSpT 0x6 /* include non-diffuse transmission */ |
| 48 |
> |
#define SDsampSpS 0x7 /* include non-diffuse scattering */ |
| 49 |
> |
#define SDsampAll 0xF /* include everything */ |
| 50 |
> |
|
| 51 |
> |
/* Projected solid angle query flags for SDsizeBSDF() */ |
| 52 |
> |
#define SDqueryVal 0x0 /* query single value */ |
| 53 |
> |
#define SDqueryMin 0x1 /* query minimum proj. solid angle */ |
| 54 |
> |
#define SDqueryMax 0x2 /* query maximum proj. solid angle */ |
| 55 |
> |
|
| 56 |
> |
/* Error codes: normal return, out of memory, file i/o, file format, bad argument, |
| 57 |
> |
bad data, unsupported feature, internal error, unknown error */ |
| 58 |
> |
typedef enum {SDEnone=0, SDEmemory, SDEfile, SDEformat, SDEargument, |
| 59 |
> |
SDEdata, SDEsupport, SDEinternal, SDEunknown} SDError; |
| 60 |
> |
|
| 61 |
> |
/* English ASCII strings corresponding to ennumerated errors */ |
| 62 |
> |
extern const char *SDerrorEnglish[]; |
| 63 |
> |
|
| 64 |
> |
/* Additional information on last error (ASCII English) */ |
| 65 |
> |
extern char SDerrorDetail[]; |
| 66 |
> |
|
| 67 |
> |
/* Holder for BSDF value and spectral color */ |
| 68 |
> |
typedef struct { |
| 69 |
> |
double cieY; /* photopic BSDF (Y) value */ |
| 70 |
> |
C_COLOR spec; /* spectral and (x,y) color */ |
| 71 |
> |
} SDValue; |
| 72 |
> |
|
| 73 |
> |
/* Cached, encoded, cumulative distribution for one incident (solid) angle */ |
| 74 |
> |
#define SD_CDIST_BASE(styp) double cTotal; \ |
| 75 |
> |
struct styp *next |
| 76 |
> |
typedef struct SDCDst_s { |
| 77 |
> |
SD_CDIST_BASE(SDCDst_s); /* base fields first */ |
| 78 |
> |
/* ...encoded distribution extends struct */ |
| 79 |
> |
} SDCDst; |
| 80 |
> |
|
| 81 |
> |
extern const SDCDst SDemptyCD; /* empty distribution */ |
| 82 |
> |
|
| 83 |
> |
/* Forward declaration of BSDF component */ |
| 84 |
> |
typedef struct SDComp_s SDComponent; |
| 85 |
> |
|
| 86 |
> |
/* Methods needed to handle BSDF components (nothing is optional) */ |
| 87 |
> |
typedef const struct { |
| 88 |
> |
/* return non-diffuse BSDF */ |
| 89 |
> |
int (*getBSDFs)(float coef[SDmaxCh], const FVECT outVec, |
| 90 |
> |
const FVECT inVec, SDComponent *sdc); |
| 91 |
> |
/* query non-diffuse PSA for vector */ |
| 92 |
> |
SDError (*queryProjSA)(double *psa, const FVECT v1, |
| 93 |
> |
const RREAL *v2, int qflags, |
| 94 |
> |
SDComponent *sdc); |
| 95 |
> |
/* get cumulative distribution */ |
| 96 |
> |
const SDCDst *(*getCDist)(const FVECT inVec, SDComponent *sdc); |
| 97 |
> |
/* sample cumulative distribution */ |
| 98 |
> |
SDError (*sampCDist)(FVECT ioVec, double randX, |
| 99 |
> |
const SDCDst *cdp); |
| 100 |
> |
/* free a spectral BSDF component */ |
| 101 |
> |
void (*freeSC)(void *dist); |
| 102 |
> |
} SDFunc; |
| 103 |
> |
|
| 104 |
> |
/* Structure to hold a spectral BSDF component (typedef SDComponent above) */ |
| 105 |
> |
struct SDComp_s { |
| 106 |
> |
C_COLOR cspec[SDmaxCh]; /* component spectral bases */ |
| 107 |
> |
SDFunc *func; /* methods for this component */ |
| 108 |
> |
void *dist; /* loaded distribution data */ |
| 109 |
> |
SDCDst *cdList; /* cumulative distribution cache */ |
| 110 |
> |
}; |
| 111 |
> |
|
| 112 |
> |
/* Container for non-diffuse BSDF components */ |
| 113 |
> |
typedef struct { |
| 114 |
> |
double minProjSA; /* minimum projected solid angle */ |
| 115 |
> |
double maxHemi; /* maximum directional hemispherical */ |
| 116 |
> |
int ncomp; /* number of separate components */ |
| 117 |
> |
SDComponent comp[1]; /* BSDF components (extends struct) */ |
| 118 |
> |
} SDSpectralDF; |
| 119 |
> |
|
| 120 |
> |
/* Loaded BSDF data */ |
| 121 |
> |
typedef struct { |
| 122 |
> |
char name[SDnameLn]; /* BSDF name (usu. derived from file) */ |
| 123 |
> |
char matn[SDnameLn]; /* material name */ |
| 124 |
> |
char makr[SDnameLn]; /* manufacturer */ |
| 125 |
> |
char *mgf; /* geometric description (if any) */ |
| 126 |
> |
float dim[3]; /* width, height, thickness (meters) */ |
| 127 |
> |
SDValue rLambFront; /* diffuse front reflectance */ |
| 128 |
> |
SDValue rLambBack; /* diffuse rear reflectance */ |
| 129 |
> |
SDValue tLamb; /* diffuse transmission */ |
| 130 |
> |
SDSpectralDF *rf, *rb; /* non-diffuse BRDF components */ |
| 131 |
> |
SDSpectralDF *tf, *tb; /* non-diffuse BTDF components */ |
| 132 |
> |
} SDData; |
| 133 |
> |
|
| 134 |
> |
/* List of loaded BSDFs */ |
| 135 |
> |
extern struct SDCache_s { |
| 136 |
> |
SDData bsdf; /* BSDF data */ |
| 137 |
> |
unsigned refcnt; /* how many callers are using us? */ |
| 138 |
> |
struct SDCache_s /* next in cache list */ |
| 139 |
> |
*next; |
| 140 |
> |
} *SDcacheList; /* Global BSDF cache */ |
| 141 |
> |
|
| 142 |
> |
/* BSDF cache retention policies */ |
| 143 |
> |
#define SDretainNone 0 /* free unreferenced BSDF data */ |
| 144 |
> |
#define SDretainBSDFs 1 /* keep loaded BSDFs in memory */ |
| 145 |
> |
#define SDretainAll 2 /* also keep cumulative cache data */ |
| 146 |
> |
|
| 147 |
> |
extern int SDretainSet; /* =SDretainNone by default */ |
| 148 |
> |
|
| 149 |
> |
/***************************************************************** |
| 150 |
> |
* The following routines are less commonly used by applications. |
| 151 |
> |
*/ |
| 152 |
> |
|
| 153 |
> |
#define SDisLoaded(sd) ((sd)->rLambFront.spec.flags != 0) |
| 154 |
> |
|
| 155 |
> |
/* Report an error to the indicated stream (in English) */ |
| 156 |
> |
extern SDError SDreportEnglish(SDError ec, FILE *fp); |
| 157 |
> |
|
| 158 |
> |
/* Shorten file path to useable BSDF name, removing suffix */ |
| 159 |
> |
extern void SDclipName(char res[SDnameLn], const char *fname); |
| 160 |
> |
|
| 161 |
> |
/* Allocate new spectral distribution function */ |
| 162 |
> |
extern SDSpectralDF *SDnewSpectralDF(int nc); |
| 163 |
> |
|
| 164 |
> |
/* Add component(s) to spectral distribution function */ |
| 165 |
> |
extern SDSpectralDF *SDaddComponent(SDSpectralDF *odf, int nadd); |
| 166 |
> |
|
| 167 |
> |
/* Free a spectral distribution function */ |
| 168 |
> |
extern void SDfreeSpectralDF(SDSpectralDF *df); |
| 169 |
> |
|
| 170 |
> |
/* Initialize an unused BSDF struct and assign name (calls SDclipName) */ |
| 171 |
> |
extern void SDclearBSDF(SDData *sd, const char *fname); |
| 172 |
> |
|
| 173 |
> |
/* Load a BSDF struct from the given file (keeps name unchanged) */ |
| 174 |
> |
extern SDError SDloadFile(SDData *sd, const char *fname); |
| 175 |
> |
|
| 176 |
> |
/* Free data associated with BSDF struct */ |
| 177 |
> |
extern void SDfreeBSDF(SDData *sd); |
| 178 |
> |
|
| 179 |
> |
/* Find writeable BSDF by name, or allocate new cache entry if absent */ |
| 180 |
> |
extern SDData *SDgetCache(const char *bname); |
| 181 |
> |
|
| 182 |
> |
/* Free cached cumulative distributions for BSDF component */ |
| 183 |
> |
extern void SDfreeCumulativeCache(SDSpectralDF *df); |
| 184 |
> |
|
| 185 |
> |
/* Sample an individual BSDF component */ |
| 186 |
> |
extern SDError SDsampComponent(SDValue *sv, FVECT ioVec, |
| 187 |
> |
double randX, SDComponent *sdc); |
| 188 |
> |
|
| 189 |
> |
/* Convert 1-dimensional random variable to N-dimensional */ |
| 190 |
> |
extern void SDmultiSamp(double t[], int n, double randX); |
| 191 |
> |
|
| 192 |
> |
/* Map a [0,1]^2 square to a unit radius disk */ |
| 193 |
> |
void SDsquare2disk(double ds[2], double seedx, double seedy); |
| 194 |
> |
|
| 195 |
> |
/* Map point on unit disk to a unit square in [0,1]^2 range */ |
| 196 |
> |
void SDdisk2square(double sq[2], double diskx, double disky); |
| 197 |
> |
|
| 198 |
> |
/***************************************************************** |
| 199 |
> |
* The calls below are the ones most applications require. |
| 200 |
> |
* All directions are assumed to be unit vectors. |
| 201 |
> |
*/ |
| 202 |
> |
|
| 203 |
> |
/* Get BSDF from cache (or load and cache it on first call) */ |
| 204 |
> |
/* Report any problems to stderr (in English), return NULL on failure */ |
| 205 |
> |
extern const SDData *SDcacheFile(const char *fname); |
| 206 |
> |
|
| 207 |
> |
/* Free a BSDF from our cache (clear all if sd==NULL) */ |
| 208 |
> |
extern void SDfreeCache(const SDData *sd); |
| 209 |
> |
|
| 210 |
> |
/* Query projected solid angle resolution for non-diffuse BSDF direction(s) */ |
| 211 |
> |
extern SDError SDsizeBSDF(double *projSA, const FVECT v1, |
| 212 |
> |
const RREAL *v2, int qflags, |
| 213 |
> |
const SDData *sd); |
| 214 |
> |
|
| 215 |
> |
/* Return BSDF for the given incident and scattered ray vectors */ |
| 216 |
> |
extern SDError SDevalBSDF(SDValue *sv, const FVECT outVec, |
| 217 |
> |
const FVECT inVec, const SDData *sd); |
| 218 |
> |
|
| 219 |
> |
/* Compute directional hemispherical scattering at given incident angle */ |
| 220 |
> |
extern double SDdirectHemi(const FVECT inVec, |
| 221 |
> |
int sflags, const SDData *sd); |
| 222 |
> |
|
| 223 |
> |
/* Sample BSDF direction based on the given random variable */ |
| 224 |
> |
extern SDError SDsampBSDF(SDValue *sv, FVECT ioVec, double randX, |
| 225 |
> |
int sflags, const SDData *sd); |
| 226 |
> |
|
| 227 |
> |
/***************************************************************** |
| 228 |
> |
* Vector math for getting between world and local BSDF coordinates. |
| 229 |
> |
* Directions may be passed unnormalized to these routines. |
| 230 |
> |
*/ |
| 231 |
> |
|
| 232 |
> |
/* Compute World->BSDF transform from surface normal and BSDF up vector */ |
| 233 |
> |
extern SDError SDcompXform(RREAL vMtx[3][3], const FVECT sNrm, |
| 234 |
> |
const FVECT uVec); |
| 235 |
> |
|
| 236 |
> |
/* Compute inverse transform */ |
| 237 |
> |
extern SDError SDinvXform(RREAL iMtx[3][3], RREAL vMtx[3][3]); |
| 238 |
> |
|
| 239 |
> |
/* Transform and normalize direction (column) vector */ |
| 240 |
> |
extern SDError SDmapDir(FVECT resVec, RREAL vMtx[3][3], |
| 241 |
> |
const FVECT inpVec); |
| 242 |
> |
|
| 243 |
> |
/* Application-specific BSDF loading routine (not part of our library) */ |
| 244 |
> |
extern SDData *loadBSDF(char *name); |
| 245 |
> |
|
| 246 |
> |
/* Application-specific BSDF error translator (not part of our library) */ |
| 247 |
> |
extern char *transSDError(SDError ec); |
| 248 |
> |
|
| 249 |
> |
#ifdef __cplusplus |
| 250 |
> |
} |
| 251 |
> |
#endif |
| 252 |
> |
#endif /* ! _BSDF_H_ */ |
