/* RCSid $Id: pmapcontrib.h,v 2.5 2016/05/17 17:39:47 rschregle Exp $ */

/* 
   =========================================================================
   Photon map routines for precomputed light source contributions; these
   routines interface to mkpmap and rcontrib.

   Roland Schregle (roland.schregle@{hslu.ch, gmail.com})
   (c) Lucerne University of Applied Sciences and Arts,
       supported by the Swiss National Science Foundation 
       (SNSF #147053, "Daylight Redirecting Components",
        SNSF #179067, "Light Fields for Spatio-Temporal Glare Assessment")
   =========================================================================
   
   $Id: pmapcontrib.h,v 2.5 2016/05/17 17:39:47 rschregle Exp $
*/

#ifndef PMAPCONTRIB_H
   #define PMAPCONTRIB_H

   #include "pmapdata.h"
   #ifndef MAXMODLIST
      #include "rcontrib.h"
   #endif
   
   /* Filename templates specific to precomputed contrib photon map:
    -- Binning parameters for rcontrib
    -- Wavelet compressed contributions (per modifier) */
   /* #define PMAP_CONTRIB_PARAMSUFFIX    "%s.rc" */
   #define PMAP_CONTRIB_WAVELETSUFFIX  "%s-%s.wvl"

   
   typedef struct {
      /* Contribution tagged by associated bin; 
         expanded representation of below */
      DCOLOR   contrib;
      unsigned bin;
   } PmapBinnedContrib;
   

   typedef union {
      struct {
         /* Compressed RGBE representaton of the above for normalised binned 
            contributions and wavelet coefficients, consisting of a 4-bit 
            mantissa + sign per RGB, a common 5-bit exponent, and a 12-bit 
            bin number. */
         char  r  : 5;
         char  g  : 5;
         char  b  : 5;
         char  e  : 5;
         int16 bin: 12;
      };
      
      uint32   rgbeBin;
   } PmapRGBEBin;
   


   MODCONT *addSourceModifier(
      LUTAB *srcContrib, unsigned *numSrcContrib, char *mod, 
      char *binParm, char *binVal, int binCnt
   );
   /* Add light source modifier mod to contribution lookup table
      srcContribs, and update numSrcContrib.  Return initialised
      contribution data for this modifier.  */

   void addSourceModfile(
      LUTAB *srcContrib, unsigned *numSrcContrib, char *modFile, 
      char *binParm, char *binVal, int binCnt
   );
   /* Add light source modifiers from file modFile to contribution lookup
    * table srcContribs, and update numSrcContrib. */
   
   void initPmapContrib (LUTAB *srcContrib);
   /* Set up photon map contributions (interface to rcmain.c) */

   void distribPhotonContrib (
      PhotonMap *pmap, LUTAB *srcContrib, unsigned numSrcContrib,
      unsigned numProc
   );
   /* Emit photons with binned light source contributions, precompute their
      contributions and build photon map */

   void photonContrib (PhotonMap *pmap, RAY *ray, COLOR irrad);
   /* Accumulate light source contributions in pmap -> srcMods from
    * photons, and return cumulative irradiance from density estimate */

#endif