--- ray/src/common/bsdf_t.h	2011/04/19 21:31:22	3.5
+++ ray/src/common/bsdf_t.h	2012/09/02 15:33:15	3.10
@@ -1,4 +1,4 @@
-/* RCSid $Id: bsdf_t.h,v 3.5 2011/04/19 21:31:22 greg Exp $ */
+/* RCSid $Id: bsdf_t.h,v 3.10 2012/09/02 15:33:15 greg Exp $ */
 /*
  *  bsdf_t.h
  *  
@@ -28,6 +28,32 @@ typedef struct SDNode_s {
 		float		v[1];		/* scattering value(s) */
 	} u;			/* subtrees or values (extends struct) */
 } SDNode;
+
+#define SD_FREFL	1	/* component reflects off front side */
+#define SD_BREFL	2	/* component reflects off back side */
+#define SD_FXMIT	3	/* component transmits through front side */
+#define SD_BXMIT	4	/* component transmits through back side */
+
+/* Variable-resolution BSDF holder */
+typedef struct {
+	int	sidef;		/* transmitted component? */
+	SDNode	*st;		/* BSDF tree */
+} SDTre;
+
+/* Holder for cumulative distribution (sum of BSDF * projSA) */
+typedef struct SDTreCDst_s {
+				/* base fields; must come first */
+	SD_CDIST_BASE(SDTreCDst_s);
+	double	clim[2][2];	/* input coordinate limits */
+	double	max_psa;	/* maximum projected solid angle */
+	short	sidef;		/* which mode is in play */
+	short	isodist;	/* isotropic distribution? */
+	int	calen;		/* cumulative array length */
+	struct {
+		unsigned	hndx;	/* hilbert index */
+		unsigned	cuml;	/* cumulative value */
+	}		carr[1];	/* cumulative array (extends struct) */
+} SDTreCDst;	
 
 #ifdef _EZXML_H
 /* Load a variable-resolution BSDF tree from an open XML file */