eic-opticks/qudarap/qprop.h

0001 #pragma once
0002 /**
0003 qprop.h
0004 ========
0005
0006 HMM: this relies on the prop arrays having last column integer
0007 annotation as done by NP::combine but there is no naming
0008 or anything that stresses that
0009
0010 **/
0011
0012
0013
0014 #if defined(__CUDACC__) || defined(__CUDABE__)
0015    #define QPROP_METHOD __device__
0016 #else
0017    #define QPROP_METHOD
0018 #endif
0019
0020 #include "sview.h"
0021
0022
0023 template<typename T>
0024 struct qprop
0025 {
0026     T* pp ;
0027     unsigned width ;
0028     unsigned height ;
0029
0030 #if defined(__CUDACC__) || defined(__CUDABE__) || defined( MOCK_CURAND )
0031     QPROP_METHOD T  interpolate( unsigned iprop, T x );
0032 #else
0033     qprop()
0034         :
0035         pp(nullptr),
0036         width(0),
0037         height(0)
0038     {
0039     }
0040 #endif
0041
0042 };
0043
0044
0045 #if defined(__CUDACC__) || defined(__CUDABE__) || defined(MOCK_CURAND)
0046
0047 /**
0048 qprop<T>::interpolate
0049 -----------------------
0050
0051 1. access property data for index iprop
0052 2. interpret the last column to obtain the number of payload values
0053 3. binary search to find the bin relevant to domain argument x
0054 4. linear interpolation to yield the y value at x
0055
0056 **/
0057
0058 template <typename T>
0059 inline QPROP_METHOD T qprop<T>::interpolate( unsigned iprop, T x )
0060 {
0061     const T* vv = pp + width*iprop ;
0062
0063     int ni = sview::int_from<T>( *(vv+width-1) ) ;
0064
0065     //printf("//qprop:interpolate iprop %d width %d height %d ni %d \n", iprop, width, height, ni );
0066
0067     int lo = 0 ;
0068     int hi = ni-1 ;
0069
0070     if( x <= vv[2*lo+0] ) return vv[2*lo+1] ;
0071     if( x >= vv[2*hi+0] ) return vv[2*hi+1] ;
0072
0073     while (lo < hi-1)
0074     {
0075         int mi = (lo+hi)/2;
0076         if (x < vv[2*mi+0]) hi = mi ;
0077         else lo = mi;
0078     }
0079
0080     T dy = vv[2*hi+1] - vv[2*lo+1] ;
0081     T dx = vv[2*hi+0] - vv[2*lo+0] ;
0082     T  y = vv[2*lo+1] + dy*(x-vv[2*lo+0])/dx ;
0083     return y ;
0084 }
0085
0086
0087 #endif
0088