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/* RCSid $Id: interp2d.h,v 2.1 2013/02/09 00:55:40 greg Exp $ */ |
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/* |
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* Header for interpolation of anisotropic values on 2-D plane. |
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* |
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* G.Ward Feb 2013 |
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*/ |
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#define NI2DSMF 0.42f /* minimal smoothing radius */ |
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#define NI2DIR (2*4) /* # interpolation directions */ |
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/* Data structure for interpolant */ |
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typedef struct { |
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int ns; /* number of sample positions */ |
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float rmin; /* minimum valid radius (default=.5) */ |
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float smf; /* smoothing factor (def=NI2DSMF) */ |
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unsigned short (*ra)[NI2DIR]; /* anisotropic radii (private) */ |
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float spt[1][2]; /* sample positions (extends struct) */ |
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} INTERP2; |
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/* Allocate a new set of interpolation samples (caller assigns spt[] array) */ |
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extern INTERP2 *interp2_alloc(int nsamps); |
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/* Resize interpolation array (caller must assign any new values) */ |
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extern INTERP2 *interp2_realloc(INTERP2 *ip, int nsamps); |
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/* Assign full set of normalized weights to interpolate the given location */ |
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extern int interp2_weights(float wtv[], INTERP2 *ip, double x, double y); |
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/* Get normalized weights and indexes for n best samples in descending order */ |
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extern int interp2_topsamp(float wt[], int si[], const int n, |
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INTERP2 *ip, double x, double y); |
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/* Free interpolant */ |
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extern void interp2_free(INTERP2 *ip); |
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/* (Re)compute anisotropic basis function interpolant (normally automatic) */ |
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extern int interp2_analyze(INTERP2 *ip); |
