/*

Brian Curless

Computer Graphics Laboratory
Stanford University

---------------------------------------------------------------------

Copyright (1997) The Board of Trustees of the Leland Stanford Junior
University. Except for commercial resale, lease, license or other
commercial transactions, permission is hereby given to use, copy,
modify this software for academic purposes only.  No part of this
software or any derivatives thereof may be used in the production of
computer models for resale or for use in a commercial
product. STANFORD MAKES NO REPRESENTATIONS OR WARRANTIES OF ANY KIND
CONCERNING THIS SOFTWARE.  No support is implied or provided.

*/


#ifndef _OCC_GRID_RLE_
#define _OCC_GRID_RLE_

#include "vrip.h"
#include "ChunkAllocator.h"
#include <limits.h>
#include "OccGrid.h"

typedef ushort RunLength;


class OccScanlineRLE {

  public:

    RunLength *allocatedLengths;
    OccElement *allocatedElements;
    RunLength *lengths;
    OccElement *elements;
    RunLength *currentLength;
    OccElement *currentElem;

    OccScanlineRLE();
    OccScanlineRLE(int dim);
    ~OccScanlineRLE();

    void reset();
    OccElement *getNextElement();
    RunLength getNextLength();
    void putNextElement(OccElement *element);
    void putNextLength(RunLength length);
};



class OccGridRLE {

  public:
    enum {CONSTANT_DATA, VARYING_DATA, END_OF_RUN=USHRT_MAX};
    enum {FALSE_DATA_BIT=0x8000};
    static const ushort HIGHEST_BIT = 0x8000;

    int xdim, ydim, zdim;
    float resolution;
    vec3f origin;
    vec3f *sliceOrigins;
    int axis;
    int flip;

    RunLength **lengthAddr;
    ChunkAllocator *lengthChunker;
    RunLength *currentLength;

    OccElement **elementAddr;
    ChunkAllocator *elementChunker;
    OccElement *currentElem;

    OccScanlineRLE *rleScanline;
    OccElement *slice;
    OccElement *otherSlice;
    OccElement *scanline;
    OccElement *defaultElement;
    int transpXZbytesPerScanline;
    uchar *transpXZslice;

    OccElement emptyNoWeight;
    OccElement fullNoWeight;

    OccGridRLE();
    OccGridRLE(int,int,int,int);

    void init(int,int,int,int);
    void freeSpace();

    void copy(OccGridRLE *other);
    void copyParams(OccGridRLE *other);

    int transposeXZ(OccGridRLE *other);
    int transposeXY(OccGridRLE *other);
    int transposeYZ(OccGridRLE *other);
    
    void clear();
    void reset();

    OccElement voxRead (int x, int y, int z);
    void       voxWrite(int x, int y, int z, OccElement &el);

    OccGrid *voxExpand();
    void voxRLE(OccGrid *og);
  
    OccElement *getSlice(const char *axis, int sliceNum, int *pxdim, int *pydim);
    OccElement *getScanline(int y, int z);
    void putScanline(OccElement *line, int y, int z);
    void copyScanline(OccScanlineRLE *rleScanline, int y, int z);
    OccElement *transposeSlice(int xdim,int ydim);
    OccElement *getElement(int xx, int yy, int zz);
    void runStats(int yy, int zz, int *numRuns, int *numElems);
    int getRunType(RunLength *length);
    void setRunType(RunLength *length, int runType);
    void putNextElement(OccElement *element);
    void putNextLength(RunLength length);
    OccElement *getNextElement();
    RunLength getNextLength();
    void allocNewRun(int y, int z);
    void setScanline(int y, int z);
    int writeDen(const char *);
    int write(const char *);
    int read(const char *);
    int decideType(OccElement *);
    OccScanlineRLE *getRLEScanline(int yy, int zz);
    ~OccGridRLE();
};


inline void
OccScanlineRLE::reset()
{
    currentElem = elements;
    currentLength = lengths;
}

inline OccElement *
OccScanlineRLE::getNextElement()
{
    return currentElem++;
}


inline RunLength 
OccScanlineRLE::getNextLength()
{
    return *currentLength++;
}


inline void 
OccScanlineRLE::putNextElement(OccElement *element)
{
    currentElem->value = element->value;
    currentElem->totalWeight = element->totalWeight;
    currentElem++;
}


inline void 
OccScanlineRLE::putNextLength(RunLength length)
{
    *currentLength = length;
    currentLength++;
}


/*
void
OccScanlineRLE::copyScanline(OccScanlineRLE *rleScanline)
{
    int i;
    RunLength length;
    int runType;
    OccElement *element;

    this->reset();
    rleScanline->reset();

    while (TRUE) {
	length = rleScanline->getNextLength();
	this->putNextLength(length);

	runType = getRunType(&length);

	if (runType == OccGridRLE::END_OF_RUN)
	    break;

	if (runType == OccGridRLE::CONSTANT_DATA) {
	    element = rleScanline->getNextElement();
	    this->putNextElement(element);
	}
	else {
	    for (i=0; i<length; i++) {
		element = rleScanline->getNextElement();
		this->putNextElement(element);
	    }
	}
    }
}
*/

inline void
OccGridRLE::putNextElement(OccElement *element)
{
    OccElement *newElem = 
	(OccElement *)this->elementChunker->alloc(sizeof(OccElement));
    newElem->value = element->value;
    newElem->totalWeight = element->totalWeight;
}


inline void
OccGridRLE::putNextLength(RunLength length)
{
    RunLength *newLength = 
	(RunLength *)this->lengthChunker->alloc(sizeof(RunLength));
    *newLength = length;
}


inline OccElement *
OccGridRLE::getNextElement()
{
    return currentElem++;
}

inline RunLength 
OccGridRLE::getNextLength()
{
    return *currentLength++;
}


inline int
OccGridRLE::getRunType(RunLength *length)
{
    int flag;
    

    if (*length == OccGridRLE::END_OF_RUN)
	return OccGridRLE::END_OF_RUN;
    
    flag = *length & OccGridRLE::HIGHEST_BIT;
    *length = *length & ~OccGridRLE::HIGHEST_BIT;
    if (flag) {
	return OccGridRLE::VARYING_DATA;
    } else {
	return OccGridRLE::CONSTANT_DATA;
    }
}


inline void
OccGridRLE::setRunType(RunLength *length, int runType)
{
    if (runType == OccGridRLE::END_OF_RUN)
	*length = OccGridRLE::END_OF_RUN;
    else if (runType == OccGridRLE::VARYING_DATA)
	*length = *length | OccGridRLE::HIGHEST_BIT;

    // else leave it alone
}


inline int
OccGridRLE::decideType(OccElement *element)
{
    if ( (element->value == emptyNoWeight.value &&
	  element->totalWeight == emptyNoWeight.totalWeight) ||
	 (element->value == fullNoWeight.value &&
	  element->totalWeight == fullNoWeight.totalWeight) ) {

	return OccGridRLE::CONSTANT_DATA;

    } else {

	return OccGridRLE::VARYING_DATA;

    }
}

#endif