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#ifndef lint |
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static const char RCSid[] = "$Id$"; |
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#endif |
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/* |
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* Routines for handling BSDF data within mkillum |
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*/ |
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|
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#include "mkillum.h" |
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#include "paths.h" |
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|
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|
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struct BSDF_data * |
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load_BSDF( /* load BSDF data from file */ |
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char *fname |
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) |
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{ |
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char *path; |
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FILE *fp; |
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struct BSDF_data *dp; |
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|
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path = getpath(fname, getrlibpath(), R_OK); |
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if (path == NULL) { |
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sprintf(errmsg, "cannot find BSDF file \"%s\"", fname); |
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error(WARNING, errmsg); |
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return(NULL); |
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} |
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if ((fp = fopen(path, "r")) == NULL) { |
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sprintf(errmsg, "cannot open BSDF \"%s\"", path); |
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error(WARNING, errmsg); |
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return(NULL); |
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} |
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dp = (struct BSDF_data *)malloc(sizeof(struct BSDF_data)); |
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if (dp == NULL) |
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goto memerr; |
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/* etc... */ |
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fclose(fp); |
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return(dp); |
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memerr: |
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error(SYSTEM, "out of memory in load_BSDF"); |
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return NULL; /* pro forma return */ |
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} |
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|
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|
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void |
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free_BSDF( /* free BSDF data structure */ |
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struct BSDF_data *b |
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) |
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{ |
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if (b == NULL) |
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return; |
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free(b->inc_dir); |
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free(b->inc_rad); |
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free(b->out_dir); |
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free(b->out_rad); |
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free(b->bsdf); |
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free(b); |
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} |
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|
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|
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void |
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r_BSDF_incvec( /* compute random input vector at given location */ |
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FVECT v, |
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struct BSDF_data *b, |
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int i, |
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double rv, |
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MAT4 xm |
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) |
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{ |
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FVECT pert; |
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double rad; |
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int j; |
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|
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getBSDF_incvec(v, b, i); |
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rad = getBSDF_incrad(b, i); |
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multisamp(pert, 3, rv); |
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for (j = 0; j < 3; j++) |
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v[j] += rad*(2.*pert[j] - 1.); |
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if (xm != NULL) |
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multv3(v, v, xm); |
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normalize(v); |
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} |
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|
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|
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void |
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r_BSDF_outvec( /* compute random output vector at given location */ |
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FVECT v, |
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struct BSDF_data *b, |
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int o, |
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double rv, |
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MAT4 xm |
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) |
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{ |
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FVECT pert; |
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double rad; |
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int j; |
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|
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getBSDF_outvec(v, b, o); |
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rad = getBSDF_outrad(b, o); |
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multisamp(pert, 3, rv); |
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for (j = 0; j < 3; j++) |
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v[j] += rad*(2.*pert[j] - 1.); |
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if (xm != NULL) |
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multv3(v, v, xm); |
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normalize(v); |
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} |
