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/* RCSid $Id: bsdfrep.h,v 2.9 2013/10/19 00:11:50 greg Exp $ */ |
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/* |
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* Definitions for BSDF representation used to interpolate measured data. |
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* |
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* G. Ward |
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*/ |
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#include "bsdf.h" |
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#define DEBUG 1 |
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#ifndef GRIDRES |
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#define GRIDRES (1<<8) /* grid resolution per side */ |
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#endif |
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/* convert to/from coded radians */ |
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#define ANG2R(r) (int)((r)*((1<<16)/M_PI)) |
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#define R2ANG(c) (((c)+.5)*(M_PI/(1<<16))) |
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typedef struct { |
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float vsum; /* DSF sum */ |
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unsigned int nval; /* number of values in sum */ |
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unsigned short crad; /* radius (coded angle) */ |
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} GRIDVAL; /* grid value */ |
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typedef struct { |
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float peak; /* lobe value at peak */ |
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unsigned short crad; /* radius (coded angle) */ |
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unsigned char gx, gy; /* grid position */ |
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} RBFVAL; /* radial basis function value */ |
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struct s_rbfnode; /* forward declaration of RBF struct */ |
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typedef struct s_migration { |
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struct s_migration *next; /* next in global edge list */ |
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struct s_rbfnode *rbfv[2]; /* from,to vertex */ |
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struct s_migration *enxt[2]; /* next from,to sibling */ |
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float mtx[1]; /* matrix (extends struct) */ |
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} MIGRATION; /* migration link (winged edge structure) */ |
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typedef struct s_rbfnode { |
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int ord; /* ordinal position in list */ |
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struct s_rbfnode *next; /* next in global RBF list */ |
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MIGRATION *ejl; /* edge list for this vertex */ |
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FVECT invec; /* incident vector direction */ |
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double vtotal; /* volume for normalization */ |
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int nrbf; /* number of RBFs */ |
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RBFVAL rbfa[1]; /* RBF array (extends struct) */ |
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} RBFNODE; /* RBF representation of DSF @ 1 incidence */ |
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/* symmetry operations */ |
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#define MIRROR_X 1 /* mirror(ed) x-coordinate */ |
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#define MIRROR_Y 2 /* mirror(ed) y-coordinate */ |
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/* represented incident quadrants */ |
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#define INP_QUAD1 1 /* 0-90 degree quadrant */ |
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#define INP_QUAD2 2 /* 90-180 degree quadrant */ |
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#define INP_QUAD3 4 /* 180-270 degree quadrant */ |
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#define INP_QUAD4 8 /* 270-360 degree quadrant */ |
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/* active grid resolution */ |
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extern int grid_res; |
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/* coverage/symmetry using INP_QUAD? flags */ |
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extern int inp_coverage; |
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/* all incident angles in-plane so far? */ |
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extern int single_plane_incident; |
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/* input/output orientations */ |
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extern int input_orient; |
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extern int output_orient; |
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/* log BSDF histogram */ |
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#define HISTLEN 256 |
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#define BSDF2BIG (1./M_PI) |
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#define BSDF2SML 1e-8 |
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#define HISTLNR 17.2759509 /* log(BSDF2BIG/BSDF2SML) */ |
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extern unsigned long bsdf_hist[HISTLEN]; |
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#define histndx(v) (int)(log((v)*(1./BSDF2SML))*(HISTLEN/HISTLNR)) |
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#define histval(i) (exp(((i)+.5)*(HISTLNR/HISTLEN))*BSDF2SML) |
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/* BSDF value for boundary regions */ |
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extern double bsdf_min; |
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/* processed incident DSF measurements */ |
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extern RBFNODE *dsf_list; |
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/* RBF-linking matrices (edges) */ |
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extern MIGRATION *mig_list; |
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#define mtx_nrows(m) (m)->rbfv[0]->nrbf |
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#define mtx_ncols(m) (m)->rbfv[1]->nrbf |
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#define mtx_coef(m,i,j) (m)->mtx[(i)*mtx_ncols(m) + (j)] |
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#define is_src(rbf,m) ((rbf) == (m)->rbfv[0]) |
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#define is_dest(rbf,m) ((rbf) == (m)->rbfv[1]) |
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#define nextedge(rbf,m) (m)->enxt[is_dest(rbf,m)] |
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#define opp_rbf(rbf,m) (m)->rbfv[is_src(rbf,m)] |
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#define round(v) (int)((v) + .5 - ((v) < -.5)) |
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#define BSDFREP_FMT "BSDF_RBFmesh" |
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/* global argv[0] */ |
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extern char *progname; |
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/* get theta value in degrees [0,180) range */ |
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#define get_theta180(v) ((180./M_PI)*acos((v)[2])) |
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/* get phi value in degrees, [0,360) range */ |
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#define get_phi360(v) ((180./M_PI)*atan2((v)[1],(v)[0]) + 360.*((v)[1]<0)) |
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/* our loaded grid for this incident angle */ |
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extern double theta_in_deg, phi_in_deg; |
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extern GRIDVAL dsf_grid[GRIDRES][GRIDRES]; |
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/* Register new input direction */ |
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extern int new_input_direction(double new_theta, double new_phi); |
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#define new_input_vector(v)\ |
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new_input_direction(get_theta180(v),get_phi360(v)) |
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/* Apply symmetry to the given vector based on distribution */ |
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extern int use_symmetry(FVECT vec); |
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/* Reverse symmetry based on what was done before */ |
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extern void rev_symmetry(FVECT vec, int sym); |
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/* Reverse symmetry for an RBF distribution */ |
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extern void rev_rbf_symmetry(RBFNODE *rbf, int sym); |
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/* Rotate RBF to correspond to given incident vector */ |
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extern void rotate_rbf(RBFNODE *rbf, const FVECT invec); |
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/* Compute volume associated with Gaussian lobe */ |
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extern double rbf_volume(const RBFVAL *rbfp); |
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/* Compute outgoing vector from grid position */ |
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extern void ovec_from_pos(FVECT vec, int xpos, int ypos); |
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/* Compute grid position from normalized input/output vector */ |
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extern void pos_from_vec(int pos[2], const FVECT vec); |
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/* Evaluate RBF for DSF at the given normalized outgoing direction */ |
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extern double eval_rbfrep(const RBFNODE *rp, const FVECT outvec); |
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/* Insert a new directional scattering function in our global list */ |
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extern int insert_dsf(RBFNODE *newrbf); |
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/* Get the DSF indicated by its ordinal position */ |
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extern RBFNODE * get_dsf(int ord); |
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/* Get triangle surface orientation (unnormalized) */ |
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extern void tri_orient(FVECT vres, const FVECT v1, |
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const FVECT v2, const FVECT v3); |
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/* Determine if vertex order is reversed (inward normal) */ |
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extern int is_rev_tri(const FVECT v1, |
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const FVECT v2, const FVECT v3); |
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/* Find vertices completing triangles on either side of the given edge */ |
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extern int get_triangles(RBFNODE *rbfv[2], const MIGRATION *mig); |
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/* Clear our BSDF representation and free memory */ |
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extern void clear_bsdf_rep(void); |
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/* Write our BSDF mesh interpolant out to the given binary stream */ |
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extern void save_bsdf_rep(FILE *ofp); |
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/* Read a BSDF mesh interpolant from the given binary stream */ |
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extern int load_bsdf_rep(FILE *ifp); |
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/* Start new DSF input grid */ |
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extern void new_bsdf_data(double new_theta, double new_phi); |
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/* Add BSDF data point */ |
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extern void add_bsdf_data(double theta_out, double phi_out, |
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double val, int isDSF); |
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/* Count up filled nodes and build RBF representation from current grid */ |
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extern RBFNODE * make_rbfrep(void); |
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/* Build our triangle mesh from recorded RBFs */ |
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extern void build_mesh(void); |
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/* Find edge(s) for interpolating the given vector, applying symmetry */ |
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extern int get_interp(MIGRATION *miga[3], FVECT invec); |
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/* Partially advect between recorded incident angles and allocate new RBF */ |
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extern RBFNODE * advect_rbf(const FVECT invec, int lobe_lim); |
