src/cv/bsdfrep.h

/* RCSid $Id: bsdfrep.h,v 2.9 2013/10/19 00:11:50 greg Exp $ */
/*
 * Definitions for BSDF representation used to interpolate measured data.
 *
 *      G. Ward
 */

#include "bsdf.h"

#define DEBUG           1

#ifndef GRIDRES
#define GRIDRES         (1<<8)          /* grid resolution per side */
#endif
                                        /* convert to/from coded radians */
#define ANG2R(r)        (int)((r)*((1<<16)/M_PI))
#define R2ANG(c)        (((c)+.5)*(M_PI/(1<<16)))

typedef struct {
        float           vsum;           /* DSF sum */
        unsigned int    nval;           /* number of values in sum */
        unsigned short  crad;           /* radius (coded angle) */
} GRIDVAL;                      /* grid value */

typedef struct {
        float           peak;           /* lobe value at peak */
        unsigned short  crad;           /* radius (coded angle) */
        unsigned char   gx, gy;         /* grid position */
} RBFVAL;                       /* radial basis function value */

struct s_rbfnode;               /* forward declaration of RBF struct */

typedef struct s_migration {
        struct s_migration      *next;          /* next in global edge list */
        struct s_rbfnode        *rbfv[2];       /* from,to vertex */
        struct s_migration      *enxt[2];       /* next from,to sibling */
        float                   mtx[1];         /* matrix (extends struct) */
} MIGRATION;                    /* migration link (winged edge structure) */

typedef struct s_rbfnode {
        int                     ord;            /* ordinal position in list */
        struct s_rbfnode        *next;          /* next in global RBF list */
        MIGRATION               *ejl;           /* edge list for this vertex */
        FVECT                   invec;          /* incident vector direction */
        double                  vtotal;         /* volume for normalization */
        int                     nrbf;           /* number of RBFs */
        RBFVAL                  rbfa[1];        /* RBF array (extends struct) */
} RBFNODE;                      /* RBF representation of DSF @ 1 incidence */

                                /* symmetry operations */
#define MIRROR_X        1               /* mirror(ed) x-coordinate */
#define MIRROR_Y        2               /* mirror(ed) y-coordinate */

                                /* represented incident quadrants */
#define INP_QUAD1       1               /* 0-90 degree quadrant */
#define INP_QUAD2       2               /* 90-180 degree quadrant */
#define INP_QUAD3       4               /* 180-270 degree quadrant */
#define INP_QUAD4       8               /* 270-360 degree quadrant */

                                /* active grid resolution */
extern int              grid_res;
                                /* coverage/symmetry using INP_QUAD? flags */
extern int              inp_coverage;

                                /* all incident angles in-plane so far? */
extern int              single_plane_incident;

                                /* input/output orientations */
extern int              input_orient;
extern int              output_orient;

                                /* log BSDF histogram */
#define HISTLEN         256
#define BSDF2BIG        (1./M_PI)
#define BSDF2SML        1e-8
#define HISTLNR         17.2759509              /* log(BSDF2BIG/BSDF2SML) */
extern unsigned long    bsdf_hist[HISTLEN];
#define histndx(v)      (int)(log((v)*(1./BSDF2SML))*(HISTLEN/HISTLNR))
#define histval(i)      (exp(((i)+.5)*(HISTLNR/HISTLEN))*BSDF2SML)

                                /* BSDF value for boundary regions */
extern double           bsdf_min;

                                /* processed incident DSF measurements */
extern RBFNODE          *dsf_list;

                                /* RBF-linking matrices (edges) */
extern MIGRATION        *mig_list;

#define mtx_nrows(m)    (m)->rbfv[0]->nrbf
#define mtx_ncols(m)    (m)->rbfv[1]->nrbf
#define mtx_coef(m,i,j) (m)->mtx[(i)*mtx_ncols(m) + (j)]
#define is_src(rbf,m)   ((rbf) == (m)->rbfv[0])
#define is_dest(rbf,m)  ((rbf) == (m)->rbfv[1])
#define nextedge(rbf,m) (m)->enxt[is_dest(rbf,m)]
#define opp_rbf(rbf,m)  (m)->rbfv[is_src(rbf,m)]

#define round(v)        (int)((v) + .5 - ((v) < -.5))

#define BSDFREP_FMT     "BSDF_RBFmesh"

                                /* global argv[0] */
extern char             *progname;

                                /* get theta value in degrees [0,180) range */
#define get_theta180(v) ((180./M_PI)*acos((v)[2]))
                                /* get phi value in degrees, [0,360) range */
#define get_phi360(v)   ((180./M_PI)*atan2((v)[1],(v)[0]) + 360.*((v)[1]<0))

                                /* our loaded grid for this incident angle */
extern double           theta_in_deg, phi_in_deg;
extern GRIDVAL          dsf_grid[GRIDRES][GRIDRES];

/* Register new input direction */
extern int              new_input_direction(double new_theta, double new_phi);

#define new_input_vector(v)\
                        new_input_direction(get_theta180(v),get_phi360(v))

/* Apply symmetry to the given vector based on distribution */
extern int              use_symmetry(FVECT vec);

/* Reverse symmetry based on what was done before */
extern void             rev_symmetry(FVECT vec, int sym);

/* Reverse symmetry for an RBF distribution */
extern void             rev_rbf_symmetry(RBFNODE *rbf, int sym);

/* Rotate RBF to correspond to given incident vector */
extern void             rotate_rbf(RBFNODE *rbf, const FVECT invec);

/* Compute volume associated with Gaussian lobe */
extern double           rbf_volume(const RBFVAL *rbfp);

/* Compute outgoing vector from grid position */
extern void             ovec_from_pos(FVECT vec, int xpos, int ypos);

/* Compute grid position from normalized input/output vector */
extern void             pos_from_vec(int pos[2], const FVECT vec);

/* Evaluate RBF for DSF at the given normalized outgoing direction */
extern double           eval_rbfrep(const RBFNODE *rp, const FVECT outvec);

/* Insert a new directional scattering function in our global list */
extern int              insert_dsf(RBFNODE *newrbf);

/* Get the DSF indicated by its ordinal position */
extern RBFNODE *        get_dsf(int ord);

/* Get triangle surface orientation (unnormalized) */
extern void             tri_orient(FVECT vres, const FVECT v1,
                                        const FVECT v2, const FVECT v3);

/* Determine if vertex order is reversed (inward normal) */
extern int              is_rev_tri(const FVECT v1,
                                        const FVECT v2, const FVECT v3);

/* Find vertices completing triangles on either side of the given edge */
extern int              get_triangles(RBFNODE *rbfv[2], const MIGRATION *mig);

/* Clear our BSDF representation and free memory */
extern void             clear_bsdf_rep(void);

/* Write our BSDF mesh interpolant out to the given binary stream */
extern void             save_bsdf_rep(FILE *ofp);

/* Read a BSDF mesh interpolant from the given binary stream */
extern int              load_bsdf_rep(FILE *ifp);

/* Start new DSF input grid */
extern void             new_bsdf_data(double new_theta, double new_phi);

/* Add BSDF data point */
extern void             add_bsdf_data(double theta_out, double phi_out,
                                        double val, int isDSF);

/* Count up filled nodes and build RBF representation from current grid */ 
extern RBFNODE *        make_rbfrep(void);

/* Build our triangle mesh from recorded RBFs */
extern void             build_mesh(void);

/* Find edge(s) for interpolating the given vector, applying symmetry */
extern int              get_interp(MIGRATION *miga[3], FVECT invec);

/* Partially advect between recorded incident angles and allocate new RBF */
extern RBFNODE *        advect_rbf(const FVECT invec, int lobe_lim);
Revision:	2.10
Committed:	Mon Oct 21 18:33:15 2013 UTC (12 years ago) by greg
Content type:	text/plain
Branch:	MAIN
Changes since 2.9:	+2 -2 lines
Log Message:	Major overhaul/redesign of radial basis function derivation
#	User	Rev	Content
1	greg	2.10	/* RCSid $Id: bsdfrep.h,v 2.9 2013/10/19 00:11:50 greg Exp $ */
2	greg	2.1	/*
3			* Definitions for BSDF representation used to interpolate measured data.
4			*
5			* G. Ward
6			*/
7
8			#include "bsdf.h"
9
10			#define DEBUG 1
11
12			#ifndef GRIDRES
13	greg	2.10	#define GRIDRES (1<<8) /* grid resolution per side */
14	greg	2.1	#endif
15			/* convert to/from coded radians */
16			#define ANG2R(r) (int)((r)*((1<<16)/M_PI))
17			#define R2ANG(c) (((c)+.5)*(M_PI/(1<<16)))
18
19			typedef struct {
20			float vsum; /* DSF sum */
21	greg	2.9	unsigned int nval; /* number of values in sum */
22	greg	2.1	unsigned short crad; /* radius (coded angle) */
23			} GRIDVAL; /* grid value */
24
25			typedef struct {
26			float peak; /* lobe value at peak */
27			unsigned short crad; /* radius (coded angle) */
28			unsigned char gx, gy; /* grid position */
29			} RBFVAL; /* radial basis function value */
30
31			struct s_rbfnode; /* forward declaration of RBF struct */
32
33			typedef struct s_migration {
34			struct s_migration next; / next in global edge list */
35			struct s_rbfnode rbfv[2]; / from,to vertex */
36			struct s_migration enxt[2]; / next from,to sibling */
37			float mtx[1]; /* matrix (extends struct) */
38			} MIGRATION; /* migration link (winged edge structure) */
39
40			typedef struct s_rbfnode {
41			int ord; /* ordinal position in list */
42			struct s_rbfnode next; / next in global RBF list */
43			MIGRATION ejl; / edge list for this vertex */
44			FVECT invec; /* incident vector direction */
45			double vtotal; /* volume for normalization */
46			int nrbf; /* number of RBFs */
47			RBFVAL rbfa[1]; /* RBF array (extends struct) */
48			} RBFNODE; /* RBF representation of DSF @ 1 incidence */
49
50			/* symmetry operations */
51			#define MIRROR_X 1 /* mirror(ed) x-coordinate */
52			#define MIRROR_Y 2 /* mirror(ed) y-coordinate */
53
54			/* represented incident quadrants */
55			#define INP_QUAD1 1 /* 0-90 degree quadrant */
56			#define INP_QUAD2 2 /* 90-180 degree quadrant */
57			#define INP_QUAD3 4 /* 180-270 degree quadrant */
58			#define INP_QUAD4 8 /* 270-360 degree quadrant */
59
60	greg	2.5	/* active grid resolution */
61			extern int grid_res;
62	greg	2.3	/* coverage/symmetry using INP_QUAD? flags */
63	greg	2.1	extern int inp_coverage;
64
65			/* all incident angles in-plane so far? */
66			extern int single_plane_incident;
67
68			/* input/output orientations */
69			extern int input_orient;
70			extern int output_orient;
71
72	greg	2.7	/* log BSDF histogram */
73			#define HISTLEN 256
74			#define BSDF2BIG (1./M_PI)
75			#define BSDF2SML 1e-8
76			#define HISTLNR 17.2759509 /* log(BSDF2BIG/BSDF2SML) */
77	greg	2.9	extern unsigned long bsdf_hist[HISTLEN];
78	greg	2.7	#define histndx(v) (int)(log((v)(1./BSDF2SML))(HISTLEN/HISTLNR))
79			#define histval(i) (exp(((i)+.5)(HISTLNR/HISTLEN))BSDF2SML)
80
81			/* BSDF value for boundary regions */
82			extern double bsdf_min;
83
84	greg	2.1	/* processed incident DSF measurements */
85			extern RBFNODE *dsf_list;
86
87			/* RBF-linking matrices (edges) */
88			extern MIGRATION *mig_list;
89
90	greg	2.3	#define mtx_nrows(m) (m)->rbfv[0]->nrbf
91			#define mtx_ncols(m) (m)->rbfv[1]->nrbf
92	greg	2.2	#define mtx_coef(m,i,j) (m)->mtx[(i)*mtx_ncols(m) + (j)]
93	greg	2.1	#define is_src(rbf,m) ((rbf) == (m)->rbfv[0])
94			#define is_dest(rbf,m) ((rbf) == (m)->rbfv[1])
95			#define nextedge(rbf,m) (m)->enxt[is_dest(rbf,m)]
96			#define opp_rbf(rbf,m) (m)->rbfv[is_src(rbf,m)]
97
98			#define round(v) (int)((v) + .5 - ((v) < -.5))
99
100	greg	2.2	#define BSDFREP_FMT "BSDF_RBFmesh"
101	greg	2.1
102			/* global argv[0] */
103			extern char *progname;
104
105			/* get theta value in degrees [0,180) range */
106	greg	2.3	#define get_theta180(v) ((180./M_PI)*acos((v)[2]))
107	greg	2.1	/* get phi value in degrees, [0,360) range */
108	greg	2.4	#define get_phi360(v) ((180./M_PI)atan2((v)[1],(v)[0]) + 360.((v)[1]<0))
109	greg	2.1
110			/* our loaded grid for this incident angle */
111			extern double theta_in_deg, phi_in_deg;
112			extern GRIDVAL dsf_grid[GRIDRES][GRIDRES];
113
114			/* Register new input direction */
115			extern int new_input_direction(double new_theta, double new_phi);
116
117			#define new_input_vector(v)\
118			new_input_direction(get_theta180(v),get_phi360(v))
119
120			/* Apply symmetry to the given vector based on distribution */
121			extern int use_symmetry(FVECT vec);
122
123			/* Reverse symmetry based on what was done before */
124			extern void rev_symmetry(FVECT vec, int sym);
125
126			/* Reverse symmetry for an RBF distribution */
127			extern void rev_rbf_symmetry(RBFNODE *rbf, int sym);
128
129	greg	2.6	/* Rotate RBF to correspond to given incident vector */
130			extern void rotate_rbf(RBFNODE *rbf, const FVECT invec);
131
132	greg	2.1	/* Compute volume associated with Gaussian lobe */
133			extern double rbf_volume(const RBFVAL *rbfp);
134
135			/* Compute outgoing vector from grid position */
136			extern void ovec_from_pos(FVECT vec, int xpos, int ypos);
137
138			/* Compute grid position from normalized input/output vector */
139			extern void pos_from_vec(int pos[2], const FVECT vec);
140
141			/* Evaluate RBF for DSF at the given normalized outgoing direction */
142			extern double eval_rbfrep(const RBFNODE *rp, const FVECT outvec);
143
144			/* Insert a new directional scattering function in our global list */
145			extern int insert_dsf(RBFNODE *newrbf);
146
147			/* Get the DSF indicated by its ordinal position */
148			extern RBFNODE * get_dsf(int ord);
149
150			/* Get triangle surface orientation (unnormalized) */
151			extern void tri_orient(FVECT vres, const FVECT v1,
152			const FVECT v2, const FVECT v3);
153
154			/* Determine if vertex order is reversed (inward normal) */
155			extern int is_rev_tri(const FVECT v1,
156			const FVECT v2, const FVECT v3);
157
158			/* Find vertices completing triangles on either side of the given edge */
159			extern int get_triangles(RBFNODE rbfv[2], const MIGRATION mig);
160
161	greg	2.3	/* Clear our BSDF representation and free memory */
162			extern void clear_bsdf_rep(void);
163
164	greg	2.1	/* Write our BSDF mesh interpolant out to the given binary stream */
165			extern void save_bsdf_rep(FILE *ofp);
166
167			/* Read a BSDF mesh interpolant from the given binary stream */
168			extern int load_bsdf_rep(FILE *ifp);
169
170			/* Start new DSF input grid */
171			extern void new_bsdf_data(double new_theta, double new_phi);
172
173			/* Add BSDF data point */
174			extern void add_bsdf_data(double theta_out, double phi_out,
175			double val, int isDSF);
176
177			/* Count up filled nodes and build RBF representation from current grid */
178			extern RBFNODE * make_rbfrep(void);
179
180			/* Build our triangle mesh from recorded RBFs */
181			extern void build_mesh(void);
182
183			/* Find edge(s) for interpolating the given vector, applying symmetry */
184			extern int get_interp(MIGRATION *miga[3], FVECT invec);
185
186			/* Partially advect between recorded incident angles and allocate new RBF */
187	greg	2.8	extern RBFNODE * advect_rbf(const FVECT invec, int lobe_lim);