--- ray/src/common/bsdf.h	2011/02/19 01:48:59	2.6
+++ ray/src/common/bsdf.h	2011/04/24 19:39:21	2.12
@@ -1,4 +1,4 @@
-/* RCSid $Id: bsdf.h,v 2.6 2011/02/19 01:48:59 greg Exp $ */
+/* RCSid $Id: bsdf.h,v 2.12 2011/04/24 19:39:21 greg Exp $ */
 /*
  *  bsdf.h
  *  
@@ -9,6 +9,11 @@
  *	in the surface plane pointed to the right as seen from the front.
  *	This means the Y-axis is "up" and the Z-axis is the surface normal.
  *
+ *  Note that we reverse the identification of "front" and "back" from
+ *	the conventions used in WINDOW 6.  "Front" in our library points
+ *	in the +Z direction, towards the interior of the space rather
+ *	than the exterior.
+ *
  *  BSDF vectors always oriented away from surface, even when "incident."
  *
  *  Created by Greg Ward on 1/10/11.
@@ -28,7 +33,7 @@ extern "C" {
 #define	SDnameLn	128		/* maximum BSDF name length */
 #define	SDmaxCh		3		/* maximum # spectral channels */
 
-/* Component flags for SDsampBSDF() and SDhemiScatter() */
+/* Component flags for SDsampBSDF() and SDdirectHemi() */
 #define	SDsampR		0x1		/* include reflection */
 #define	SDsampT		0x2		/* include transmission */
 #define	SDsampS		0x3		/* include scattering (R+T) */
@@ -39,11 +44,10 @@ extern "C" {
 #define	SDsampSpS	0x7		/* include non-diffuse scattering */
 #define	SDsampAll	0xF		/* include everything */
 
-/* Projected solid angle query flags fos SDsizeBSDF() */
-#define	SDqueryInc	0x1		/* query incoming vector */
-#define	SDqueryOut	0x2		/* query outgoing vector */
-#define	SDqueryMin	0x4		/* query minimum proj. solid angle */
-#define	SDqueryMax	0x8		/* query maximum proj. solid angle */
+/* Projected solid angle query flags for SDsizeBSDF() */
+#define SDqueryVal	0x0		/* query single value */
+#define	SDqueryMin	0x1		/* query minimum proj. solid angle */
+#define	SDqueryMax	0x2		/* query maximum proj. solid angle */
 
 /* Error codes: normal return, out of memory, file i/o, file format, bad argument,
 		 bad data, unsupported feature, internal error, unknown error */
@@ -77,14 +81,15 @@ typedef struct SDComp_s	SDComponent;
 typedef const struct {
 					/* return non-diffuse BSDF */
 	int		(*getBSDFs)(float coef[SDmaxCh], const FVECT outVec,
-				    const FVECT inVec, const void *dist);
+				    const FVECT inVec, SDComponent *sdc);
 					/* query non-diffuse PSA for vector */
-	SDError		(*queryProjSA)(double *psa, const FVECT vec,
-						int qflags, const void *dist);
+	SDError		(*queryProjSA)(double *psa, const FVECT v1,
+						const RREAL *v2, int qflags,
+						SDComponent *sdc);
 					/* get cumulative distribution */
 	const SDCDst	*(*getCDist)(const FVECT inVec, SDComponent *sdc);
 					/* sample cumulative distribution */
-	SDError		(*sampCDist)(FVECT outVec, double randX,
+	SDError		(*sampCDist)(FVECT ioVec, double randX,
 						const SDCDst *cdp);
 					/* free a spectral BSDF component */
 	void		(*freeSC)(void *dist);
@@ -150,8 +155,8 @@ extern SDSpectralDF	*SDnewSpectralDF(int nc);
 /* Free a spectral distribution function */
 extern void		SDfreeSpectralDF(SDSpectralDF *df);
 
-/* Initialize an unused BSDF struct (clears to zeroes) */
-extern void		SDclearBSDF(SDData *sd);
+/* Initialize an unused BSDF struct and assign name (calls SDclipName) */
+extern void		SDclearBSDF(SDData *sd, const char *fname);
 
 /* Load a BSDF struct from the given file (keeps name unchanged) */
 extern SDError		SDloadFile(SDData *sd, const char *fname);
@@ -166,9 +171,8 @@ extern SDData		*SDgetCache(const char *bname);
 extern void		SDfreeCumulativeCache(SDSpectralDF *df);
 
 /* Sample an individual BSDF component */
-extern SDError		SDsampComponent(SDValue *sv, FVECT outVec,
-					const FVECT inVec, double randX,
-					SDComponent *sdc);
+extern SDError		SDsampComponent(SDValue *sv, FVECT ioVec,
+					double randX, SDComponent *sdc);
 
 /* Convert 1-dimensional random variable to N-dimensional */
 extern void		SDmultiSamp(double t[], int n, double randX);
@@ -191,9 +195,10 @@ extern const SDData	*SDcacheFile(const char *fname);
 /* Free a BSDF from our cache (clear all if NULL) */
 extern void		SDfreeCache(const SDData *sd);
 
-/* Query projected solid angle resolution for non-diffuse BSDF direction */
-extern SDError		SDsizeBSDF(double *projSA, const FVECT vec,
-					int qflags, const SDData *sd);
+/* Query projected solid angle resolution for non-diffuse BSDF direction(s) */
+extern SDError		SDsizeBSDF(double *projSA, const FVECT v1,
+					const RREAL *v2, int qflags,
+					const SDData *sd);
 
 /* Return BSDF for the given incident and scattered ray vectors */
 extern SDError		SDevalBSDF(SDValue *sv, const FVECT outVec,
@@ -204,8 +209,7 @@ extern double		SDdirectHemi(const FVECT inVec,
 					int sflags, const SDData *sd);
 
 /* Sample BSDF direction based on the given random variable */
-extern SDError		SDsampBSDF(SDValue *sv, FVECT outVec,
-					const FVECT inVec, double randX,
+extern SDError		SDsampBSDF(SDValue *sv, FVECT ioVec, double randX,
 					int sflags, const SDData *sd);
 
 /*****************************************************************