This code computes Delaunay triangulation of a cube, imports it into a LCC and writes the LCC to a PLY file.

build.sh

g++-4.8  rply.cpp CubeDTLCCPLY.cpp -lgmp -lCGAL

CubeDTLCCPLY.cpp

#include <iostream>
#include <map>
#include "rply.h"
#include <CGAL/Delaunay_triangulation_3.h>
#include <CGAL/Linear_cell_complex.h>
#include <CGAL/Linear_cell_complex_constructors.h>

using namespace std;
using namespace CGAL;

struct MyInfo
{
	template<class Refs>
	struct Dart_wrapper
	{
		typedef CGAL::Dart<3, Refs> Dart;
		typedef Cell_attribute_with_point<Refs, size_t > VertexAttribute;
		typedef cpp11::tuple<VertexAttribute> Attributes;
	};
};

typedef Exact_predicates_inexact_constructions_kernel K;
typedef Linear_cell_complex_traits<3, K> Traits;
typedef Linear_cell_complex<3,3, Traits, MyInfo> LCC;
typedef Delaunay_triangulation_3<K> Delaunay;
typedef Point_3<K> Point;

LCC lcc;
static size_t nDarts = 0;
int infiniteVertexMark;


/** \fn isInfinite(LCC::Dart_handle adart, LCC::Dart_handle infiniteVertexInLCC, LCC &alcc, const unsigned int cell_dimension)
 *  \brief Tests whether the given i-cell is infinite.
 *  \param[in] adart a dart handle to the i-cell.
 *  \param[in] cell_dimension dimension of i-cell.
 *  \return True if input vertex or face is infinite    
**/
bool isInfinite(LCC::Dart_handle adart, unsigned int cell_dimension)
{
	bool isInfinite = false;
	
	if (cell_dimension == 0)
	{
		if (lcc.is_marked(adart, infiniteVertexMark)) 
		return true;
	}

	if (cell_dimension == 2)
	{
		for (LCC::One_dart_per_incident_cell_range<0, 2>::iterator pIter = lcc.one_dart_per_incident_cell<0, 2>(adart).begin(), pIterEnd = lcc.one_dart_per_incident_cell<0, 2>(adart).end(); pIter != pIterEnd; pIter++)
		{
			if (lcc.is_marked(pIter, infiniteVertexMark)) 
			{
				isInfinite = true;
				break;
			}
		}
	}

	if (cell_dimension == 3)
	{
		for (LCC::One_dart_per_incident_cell_range<0, 3>::iterator pIter = lcc.one_dart_per_incident_cell<0, 3>(adart).begin(), pIterEnd = lcc.one_dart_per_incident_cell<0, 3>(adart).end(); pIter != pIterEnd; pIter++)
		{
			if (lcc.is_marked(pIter, infiniteVertexMark)) 
			{
				isInfinite = true;
				break;
			}
		}
	}

	return isInfinite;
}


void markInfiniteVertexDart(LCC::Dart_handle d)
{
	if (!lcc.is_marked(d, infiniteVertexMark))
	{
		lcc.mark(d, infiniteVertexMark);
		nDarts++;
	
		d = lcc.beta(d, 2, 1);
		markInfiniteVertexDart(d);

		d = lcc.beta(d, 3, 1);
		markInfiniteVertexDart(d);
	}

	return;
}


/*! \fn void writePLYOutput(LCCWithIntInfo &lcc, string fileName)
    \brief Writes mesh represented as LCC to PLY file
    \param [in] fileName Name of output PLY file   
*/
void writePLYOutput(LCC::Dart_handle dartToInfiniteVertex, string fileName)
{
	p_ply lccOutputPLY;

	if ((lccOutputPLY = ply_create(fileName.c_str(), PLY_ASCII, NULL, 0, NULL)) == NULL)
	{
		cout << "\nCannot open file for writing!!";
		exit(0);
	}


	// mark all darts defining infinite vertex
	infiniteVertexMark = lcc.get_new_mark();
	
	if (infiniteVertexMark == -1)
		exit(0);
	// Marking all darts associated with infinite vertices
	markInfiniteVertexDart(dartToInfiniteVertex);
	cout << "Number of darts associated with infinite vertex: " << nDarts << "\n";


	// count number of vertices and tets in LCC
	size_t nVertices = 0, nFaces = 0;
	for (LCC::One_dart_per_cell_range<0>::iterator pointCountIter = lcc.one_dart_per_cell<0>().begin(), pointCountIterEnd = lcc.one_dart_per_cell<0>().end(); pointCountIter != pointCountIterEnd; pointCountIter++)
		if (!isInfinite(pointCountIter, 0))
			nVertices++;

	for (LCC::One_dart_per_cell_range<2>::iterator faceCountIter = lcc.one_dart_per_cell<2>().begin(), faceCountIterEnd = lcc.one_dart_per_cell<2>().end(); faceCountIter != faceCountIterEnd; faceCountIter++)
		if(!isInfinite(faceCountIter, 2))
			nFaces++;

	ply_add_element(lccOutputPLY, "vertex", nVertices);
	ply_add_scalar_property(lccOutputPLY, "x", PLY_FLOAT);
	ply_add_scalar_property(lccOutputPLY, "y", PLY_FLOAT);
	ply_add_scalar_property(lccOutputPLY, "z", PLY_FLOAT);

	ply_add_element(lccOutputPLY, "face", 24);//nFaces); // TODO: FIX THIS 
	ply_add_list_property(lccOutputPLY, "vertex_indices", PLY_UCHAR, PLY_INT32);

	if (!ply_write_header(lccOutputPLY))
	{
		cout << "Header cannot be written!!";
		exit(0);
	}

	// write vertices
	size_t pointId = 0;
	for (LCC::One_dart_per_cell_range<0>::iterator pointIter = lcc.one_dart_per_cell<0>().begin(), pointIterEnd = lcc.one_dart_per_cell<0>().end(); pointIter != pointIterEnd; pointIter++)
	{
		if (!isInfinite(pointIter, 0))
		{
			Point pt = lcc.point(pointIter); 
			ply_write(lccOutputPLY, pt.x());
			ply_write(lccOutputPLY, pt.y());
			ply_write(lccOutputPLY, pt.z());
			lcc.info<0>(pointIter) = pointId++;
		}
	}

	// write tetrahedrons	
	LCC::Dart_handle pts[4];
	size_t i;

	size_t nFiniteTets = 0, nInfiniteTets = 0;
	for (LCC::One_dart_per_cell_range<3>::iterator tetIter = lcc.one_dart_per_cell<3>().begin(), tetIterEnd = lcc.one_dart_per_cell<3>().end(); tetIter != tetIterEnd; tetIter++)
	{
		if (!isInfinite(tetIter, 3))
		{
			i = 0;

			for (LCC::One_dart_per_incident_cell_range<0, 3>::iterator pIter = lcc.one_dart_per_incident_cell<0, 3>(tetIter).begin(), pIterEnd = lcc.one_dart_per_incident_cell<0, 3>(tetIter).end(); pIter != pIterEnd; pIter++)
				pts[i++] = pIter;
			
			ply_write(lccOutputPLY, 3);	
			// t1
			ply_write(lccOutputPLY, lcc.info<0>(pts[0]));
			ply_write(lccOutputPLY, lcc.info<0>(pts[1]));
			ply_write(lccOutputPLY, lcc.info<0>(pts[2]));
			
	ply_write(lccOutputPLY, 3);	

			// t2
			ply_write(lccOutputPLY, lcc.info<0>(pts[1]));
			ply_write(lccOutputPLY, lcc.info<0>(pts[0]));
			ply_write(lccOutputPLY, lcc.info<0>(pts[3]));
		ply_write(lccOutputPLY, 3);	
		
			// t3 	
			ply_write(lccOutputPLY, lcc.info<0>(pts[1]));
			ply_write(lccOutputPLY, lcc.info<0>(pts[3]));
			ply_write(lccOutputPLY, lcc.info<0>(pts[2]));

			ply_write(lccOutputPLY, 3);	
	// t4
			ply_write(lccOutputPLY, lcc.info<0>(pts[3]));
			ply_write(lccOutputPLY, lcc.info<0>(pts[0]));
			ply_write(lccOutputPLY, lcc.info<0>(pts[2]));
		}
	}

	lcc.free_mark(infiniteVertexMark);
	ply_close(lccOutputPLY);			
}


/*! \fn int main()
 *  \brief Main procedure
 */
int main()
{
	vector<Point> ptVector;
	
	// create a cube
	ptVector.push_back(Point(0, 0, 0));
	ptVector.push_back(Point(0, 0, 1));
	ptVector.push_back(Point(0, 1, 0));
	ptVector.push_back(Point(0, 1, 1));

	ptVector.push_back(Point(1, 0, 0));
	ptVector.push_back(Point(1, 0, 1));
	ptVector.push_back(Point(1, 1, 0));
	ptVector.push_back(Point(1, 1, 1));

	// compute Delaunay triangulation
	Delaunay DT;
	DT.insert(ptVector.begin(), ptVector.end());
	
	map<Delaunay::Cell_handle, LCC::Dart_handle>* DTToLCCMap = NULL;
	
	// import DT to LCC
	LCC::Dart_handle dartToInfiniteVertex = import_from_triangulation_3(lcc, DT, DTToLCCMap);
	
	// test if all vertices are imported correctly from DT to LCC
	for (Delaunay::Vertex_iterator vIter = DT.vertices_begin(), vIterEnd = DT.vertices_end(); vIter != vIterEnd; vIter++)
		if(DT.is_infinite(vIter))
			cout << "Infinite vertex in Delaunay triangulation: " << vIter->point() << "\n";
		else
			cout << vIter->point() << "\n";
		
	cout << "Now printing vertices of LCC:" << "\n";

	for (LCC::One_dart_per_cell_range<0>::iterator pIter = lcc.one_dart_per_cell<0>().begin(), pIterEnd = lcc.one_dart_per_cell<0>().end(); pIter != pIterEnd; pIter++)
		if (!isInfinite(pIter, 0))
			cout << lcc.point(pIter) << "\n";

	cout << "Infinite vertex in LCC: " << lcc.point(dartToInfiniteVertex) << "\n";

	// Writing LCC to PLY 
	writePLYOutput(dartToInfiniteVertex, "delaunay.ply");

	// Testing whether labelling is correct
	cout << "Number of finite Tets in DT: " << DT.number_of_finite_cells() << "\n";

	cout << "Number of infinite Tets in DT: " << DT.number_of_cells() - DT.number_of_finite_cells() << "\n";

	return 0;
}

rply.cpp

/* ----------------------------------------------------------------------
 * RPly library, read/write PLY files
 * Diego Nehab, IMPA
 * http://www.impa.br/~diego/software/rply
 *
 * This library is distributed under the MIT License. See notice
 * at the end of this file.
 * ---------------------------------------------------------------------- */
#include "rply.h"

/* ----------------------------------------------------------------------
 * Make sure we get our integer types right
 * ---------------------------------------------------------------------- */
#if defined(_MSC_VER) && (_MSC_VER < 1600)
/* C99 stdint.h only supported in MSVC++ 10.0 and up */
typedef __int8 t_ply_int8;
typedef __int16 t_ply_int16;
typedef __int32 t_ply_int32;
typedef unsigned __int8 t_ply_uint8;
typedef unsigned __int16 t_ply_uint16;
typedef unsigned __int32 t_ply_uint32;
#define PLY_INT8_MAX (127)
#define PLY_INT8_MIN (-PLY_INT8_MAX-1)
#define PLY_INT16_MAX (32767)
#define PLY_INT16_MIN (-PLY_INT16_MAX-1)
#define PLY_INT32_MAX (2147483647)
#define PLY_INT32_MIN (-PLY_INT32_MAX-1)
#define PLY_UINT8_MAX (255)
#define PLY_UINT16_MAX (65535)
#define PLY_UINT32_MAX  (4294967295)
#else
#include <stdint.h>
typedef int8_t t_ply_int8;
typedef int16_t t_ply_int16;
typedef int32_t t_ply_int32;
typedef uint8_t t_ply_uint8;
typedef uint16_t t_ply_uint16;
typedef uint32_t t_ply_uint32;
#define PLY_INT8_MAX (127)
#define PLY_INT8_MIN (-PLY_INT8_MAX-1)
#define PLY_INT16_MAX (32767)
#define PLY_INT16_MIN (-PLY_INT16_MAX-1)
#define PLY_INT32_MAX (2147483647)
#define PLY_INT32_MIN (-PLY_INT32_MAX-1)
#define PLY_UINT8_MAX (255)
#define PLY_UINT16_MAX (65535)
#define PLY_UINT32_MAX  (4294967295)
#endif

/* ----------------------------------------------------------------------
 * Constants 
 * ---------------------------------------------------------------------- */
#define WORDSIZE 256
#define LINESIZE 1024
#define BUFFERSIZE (8*1024)

typedef enum e_ply_io_mode_ {
    PLY_READ, 
    PLY_WRITE
} e_ply_io_mode;

static const char *const ply_storage_mode_list[] = {
    "binary_big_endian", "binary_little_endian", "ascii", NULL
};     /* order matches e_ply_storage_mode enum */

static const char *const ply_type_list[] = {
    "int8", "uint8", "int16", "uint16", 
    "int32", "uint32", "float32", "float64",
    "char", "uchar", "short", "ushort", 
    "int", "uint", "float", "double",
    "list", NULL
};     /* order matches e_ply_type enum */

/* ----------------------------------------------------------------------
 * Property reading callback argument
 *
 * element: name of element being processed
 * property: name of property being processed
 * nelements: number of elements of this kind in file
 * instance_index: index current element of this kind being processed
 * length: number of values in current list (or 1 for scalars)
 * value_index: index of current value int this list (or 0 for scalars)
 * value: value of property
 * pdata/idata: user data defined with ply_set_cb
 *
 * Returns handle to PLY file if succesful, NULL otherwise.
 * ---------------------------------------------------------------------- */
typedef struct t_ply_argument_ {
    p_ply_element element;
    long instance_index;
    p_ply_property property;
    long length, value_index;
    double value;
    void *pdata;
    long idata;
} t_ply_argument;

/* ----------------------------------------------------------------------
 * Property information
 *
 * name: name of this property
 * type: type of this property (list or type of scalar value)
 * length_type, value_type: type of list property count and values
 * read_cb: function to be called when this property is called
 *
 * Returns 1 if should continue processing file, 0 if should abort.
 * ---------------------------------------------------------------------- */
typedef struct t_ply_property_ {
    char name[WORDSIZE];
    e_ply_type type, value_type, length_type;
    p_ply_read_cb read_cb;
    void *pdata;
    long idata;
} t_ply_property; 

/* ----------------------------------------------------------------------
 * Element information
 *
 * name: name of this property
 * ninstances: number of elements of this type in file
 * property: property descriptions for this element
 * nproperty: number of properties in this element
 *
 * Returns 1 if should continue processing file, 0 if should abort.
 * ---------------------------------------------------------------------- */
typedef struct t_ply_element_ {
    char name[WORDSIZE];
    long ninstances;
    p_ply_property property;
    long nproperties;
} t_ply_element;

/* ----------------------------------------------------------------------
 * Input/output driver
 *
 * Depending on file mode, different functions are used to read/write 
 * property fields. The drivers make it transparent to read/write in ascii, 
 * big endian or little endian cases.
 * ---------------------------------------------------------------------- */
typedef int (*p_ply_ihandler)(p_ply ply, double *value);
typedef int (*p_ply_ichunk)(p_ply ply, void *anydata, size_t size);
typedef struct t_ply_idriver_ {
    p_ply_ihandler ihandler[16];
    p_ply_ichunk ichunk;
    const char *name;
} t_ply_idriver;
typedef t_ply_idriver *p_ply_idriver;

typedef int (*p_ply_ohandler)(p_ply ply, double value);
typedef int (*p_ply_ochunk)(p_ply ply, void *anydata, size_t size);
typedef struct t_ply_odriver_ {
    p_ply_ohandler ohandler[16];
    p_ply_ochunk ochunk;
    const char *name;
} t_ply_odriver;
typedef t_ply_odriver *p_ply_odriver;

/* ----------------------------------------------------------------------
 * Ply file handle. 
 *
 * io_mode: read or write (from e_ply_io_mode)
 * storage_mode: mode of file associated with handle (from e_ply_storage_mode)
 * element: elements description for this file
 * nelement: number of different elements in file
 * comment: comments for this file
 * ncomments: number of comments in file
 * obj_info: obj_info items for this file
 * nobj_infos: number of obj_info items in file
 * fp: file pointer associated with ply file
 * rn: skip extra char after end_header? 
 * buffer: last word/chunck of data read from ply file
 * buffer_first, buffer_last: interval of untouched good data in buffer
 * buffer_token: start of parsed token (line or word) in buffer
 * idriver, odriver: input driver used to get property fields from file 
 * argument: storage space for callback arguments
 * welement, wproperty: element/property type being written
 * winstance_index: index of instance of current element being written
 * wvalue_index: index of list property value being written 
 * wlength: number of values in list property being written
 * error_cb: error callback
 * pdata/idata: user data defined with ply_open/ply_create
 * ---------------------------------------------------------------------- */
typedef struct t_ply_ {
    e_ply_io_mode io_mode;
    e_ply_storage_mode storage_mode;
    p_ply_element element;
    long nelements;
    char *comment;
    long ncomments;
    char *obj_info;
    long nobj_infos;
    FILE *fp;
    int rn;
    char buffer[BUFFERSIZE];
    size_t buffer_first, buffer_token, buffer_last;
    p_ply_idriver idriver;
    p_ply_odriver odriver;
    t_ply_argument argument;
    long welement, wproperty;
    long winstance_index, wvalue_index, wlength;
    p_ply_error_cb error_cb;
    void *pdata;
    long idata;
} t_ply;

/* ----------------------------------------------------------------------
 * I/O functions and drivers
 * ---------------------------------------------------------------------- */
static int ply_read_word(p_ply ply);
static int ply_check_word(p_ply ply);
static void ply_finish_word(p_ply ply, size_t size);
static int ply_read_line(p_ply ply);
static int ply_check_line(p_ply ply);
static int ply_read_chunk(p_ply ply, void *anybuffer, size_t size);
static int ply_read_chunk_reverse(p_ply ply, void *anybuffer, size_t size);
static int ply_write_chunk(p_ply ply, void *anybuffer, size_t size);
static int ply_write_chunk_reverse(p_ply ply, void *anybuffer, size_t size);
static void ply_reverse(void *anydata, size_t size);

/* ----------------------------------------------------------------------
 * String functions
 * ---------------------------------------------------------------------- */
static int ply_find_string(const char *item, const char* const list[]);
static p_ply_element ply_find_element(p_ply ply, const char *name);
static p_ply_property ply_find_property(p_ply_element element, 
        const char *name);

/* ----------------------------------------------------------------------
 * Header parsing
 * ---------------------------------------------------------------------- */
static int ply_read_header_magic(p_ply ply); 
static int ply_read_header_format(p_ply ply);
static int ply_read_header_comment(p_ply ply);
static int ply_read_header_obj_info(p_ply ply);
static int ply_read_header_property(p_ply ply);
static int ply_read_header_element(p_ply ply);

/* ----------------------------------------------------------------------
 * Error handling
 * ---------------------------------------------------------------------- */
static void ply_error_cb(p_ply ply, const char *message);
static void ply_ferror(p_ply ply, const char *fmt, ...);

/* ----------------------------------------------------------------------
 * Memory allocation and initialization
 * ---------------------------------------------------------------------- */
static void ply_init(p_ply ply);
static void ply_element_init(p_ply_element element);
static void ply_property_init(p_ply_property property);
static p_ply ply_alloc(void);
static p_ply_element ply_grow_element(p_ply ply);
static p_ply_property ply_grow_property(p_ply ply, p_ply_element element);
static void *ply_grow_array(p_ply ply, void **pointer, long *nmemb, long size);

/* ----------------------------------------------------------------------
 * Special functions
 * ---------------------------------------------------------------------- */
static e_ply_storage_mode ply_arch_endian(void);
static int ply_type_check(void); 

/* ----------------------------------------------------------------------
 * Auxiliary read functions
 * ---------------------------------------------------------------------- */
static int ply_read_element(p_ply ply, p_ply_element element, 
        p_ply_argument argument);
static int ply_read_property(p_ply ply, p_ply_element element, 
        p_ply_property property, p_ply_argument argument);
static int ply_read_list_property(p_ply ply, p_ply_element element, 
        p_ply_property property, p_ply_argument argument);
static int ply_read_scalar_property(p_ply ply, p_ply_element element, 
        p_ply_property property, p_ply_argument argument);

/* ----------------------------------------------------------------------
 * Buffer support functions
 * ---------------------------------------------------------------------- */
/* pointers to tokenized word and line in buffer */
#define BWORD(p) (p->buffer + p->buffer_token)
#define BLINE(p) (p->buffer + p->buffer_token)

/* pointer to start of untouched bytes in buffer */
#define BFIRST(p) (p->buffer + p->buffer_first) 

/* number of bytes untouched in buffer */
#define BSIZE(p) (p->buffer_last - p->buffer_first) 

/* consumes data from buffer */
#define BSKIP(p, s) (p->buffer_first += s)

/* refills the buffer */
static int BREFILL(p_ply ply) {
    /* move untouched data to beginning of buffer */
    size_t size = BSIZE(ply);
    memmove(ply->buffer, BFIRST(ply), size);
    ply->buffer_last = size;
    ply->buffer_first = ply->buffer_token = 0;
    /* fill remaining with new data */
    size = fread(ply->buffer+size, 1, BUFFERSIZE-size-1, ply->fp);
    /* place sentinel so we can use str* functions with buffer */
    ply->buffer[BUFFERSIZE-1] = '\0';
    /* check if read failed */
    if (size <= 0) return 0;
    /* increase size to account for new data */
    ply->buffer_last += size;
    return 1;
}

/* We don't care about end-of-line, generally, because we
 * separate words by any white-space character.
 * Unfortunately, in binary mode, right after 'end_header', 
 * we have to know *exactly* how many characters to skip */
/* We use the end-of-line marker after the 'ply' magic
 * number to figure out what to do */
static int ply_read_header_magic(p_ply ply) {
    char *magic = ply->buffer;
    if (!BREFILL(ply)) {
        ply->error_cb(ply, "Unable to read magic number from file");
        return 0;
    }
    /* check if it is ply */
    if (magic[0] != 'p' || magic[1] != 'l' || magic[2] != 'y' 
            || !isspace(magic[3])) {
        ply->error_cb(ply, "Wrong magic number. Expected 'ply'");
        return 0;
    }
    /* figure out if we have to skip the extra character
     * after header when we reach the binary part of file */
    ply->rn = magic[3] == '\r' && magic[4] == '\n';
    BSKIP(ply, 3);
    return 1;
}

/* ----------------------------------------------------------------------
 * Exported functions
 * ---------------------------------------------------------------------- */
/* ----------------------------------------------------------------------
 * Read support functions
 * ---------------------------------------------------------------------- */
p_ply ply_open(const char *name, p_ply_error_cb error_cb, 
        long idata, void *pdata) {
    FILE *fp = NULL; 
    p_ply ply = ply_alloc();
    if (error_cb == NULL) error_cb = ply_error_cb;
    if (!ply) {
        error_cb(NULL, "Out of memory");
        return NULL;
    }
    ply->idata = idata;
    ply->pdata = pdata;
    ply->io_mode = PLY_READ;
    ply->error_cb = error_cb;
    if (!ply_type_check()) {
        error_cb(ply, "Incompatible type system");
        free(ply);
        return NULL;
    }
    assert(name);
    fp = fopen(name, "rb");
    if (!fp) {
        error_cb(ply, "Unable to open file");
        free(ply);
        return NULL;
    }
    ply->fp = fp;
    return ply;
}

int ply_read_header(p_ply ply) {
    assert(ply && ply->fp && ply->io_mode == PLY_READ);
    if (!ply_read_header_magic(ply)) return 0;
    if (!ply_read_word(ply)) return 0;
    /* parse file format */
    if (!ply_read_header_format(ply)) {
        ply_ferror(ply, "Invalid file format");
        return 0;
    }
    /* parse elements, comments or obj_infos until the end of header */
    while (strcmp(BWORD(ply), "end_header")) {
        if (!ply_read_header_comment(ply) && 
                !ply_read_header_element(ply) && 
                !ply_read_header_obj_info(ply)) {
            ply_ferror(ply, "Unexpected token '%s'", BWORD(ply));
            return 0;
        }
    }
    /* skip extra character? */
    if (ply->rn) {
        if (BSIZE(ply) < 1 && !BREFILL(ply)) {
            ply_ferror(ply, "Unexpected end of file");
            return 0;
        }
        BSKIP(ply, 1);
    }
    return 1;
}

long ply_set_read_cb(p_ply ply, const char *element_name, 
        const char* property_name, p_ply_read_cb read_cb, 
        void *pdata, long idata) {
    p_ply_element element = NULL; 
    p_ply_property property = NULL;
    assert(ply && element_name && property_name);
    element = ply_find_element(ply, element_name);
    if (!element) return 0;
    property = ply_find_property(element, property_name);
    if (!property) return 0;
    property->read_cb = read_cb;
    property->pdata = pdata;
    property->idata = idata;
    return (int) element->ninstances;
}

int ply_read(p_ply ply) {
    long i;
    p_ply_argument argument;
    assert(ply && ply->fp && ply->io_mode == PLY_READ);
    argument = &ply->argument;
    /* for each element type */
    for (i = 0; i < ply->nelements; i++) {
        p_ply_element element = &ply->element[i];
        argument->element = element;
        if (!ply_read_element(ply, element, argument))
            return 0;
    }
    return 1;
}

/* ----------------------------------------------------------------------
 * Write support functions
 * ---------------------------------------------------------------------- */
int ply_add_element(p_ply ply, const char *name, long ninstances) {
    p_ply_element element = NULL;
    assert(ply && ply->fp && ply->io_mode == PLY_WRITE);
    assert(name && strlen(name) < WORDSIZE && ninstances >= 0);
    if (strlen(name) >= WORDSIZE || ninstances < 0) {
        ply_ferror(ply, "Invalid arguments");
        return 0;
    }
    element = ply_grow_element(ply);
    if (!element) return 0;
    strcpy(element->name, name);
    element->ninstances = ninstances;
    return 1;
}

int ply_add_scalar_property(p_ply ply, const char *name, e_ply_type type) {
    p_ply_element element = NULL;
    p_ply_property property = NULL;
    assert(ply && ply->fp && ply->io_mode == PLY_WRITE);
    assert(name && strlen(name) < WORDSIZE);
    assert(type < PLY_LIST);
    if (strlen(name) >= WORDSIZE || type >= PLY_LIST) {
        ply_ferror(ply, "Invalid arguments");
        return 0;
    }
    element = &ply->element[ply->nelements-1];
    property = ply_grow_property(ply, element);
    if (!property) return 0;
    strcpy(property->name, name);
    property->type = type;
    return 1;
}

int ply_add_list_property(p_ply ply, const char *name, 
        e_ply_type length_type, e_ply_type value_type) {
    p_ply_element element = NULL;
    p_ply_property property = NULL;
    assert(ply && ply->fp && ply->io_mode == PLY_WRITE);
    assert(name && strlen(name) < WORDSIZE);
    if (strlen(name) >= WORDSIZE) {
        ply_ferror(ply, "Invalid arguments");
        return 0;
    }
    assert(length_type < PLY_LIST);
    assert(value_type < PLY_LIST);
    if (length_type >= PLY_LIST || value_type >= PLY_LIST) {
        ply_ferror(ply, "Invalid arguments");
        return 0;
    }
    element = &ply->element[ply->nelements-1];
    property = ply_grow_property(ply, element);
    if (!property) return 0;
    strcpy(property->name, name);
    property->type = PLY_LIST;
    property->length_type = length_type;
    property->value_type = value_type;
    return 1;
}

int ply_add_property(p_ply ply, const char *name, e_ply_type type,
        e_ply_type length_type, e_ply_type value_type) {
    if (type == PLY_LIST) 
        return ply_add_list_property(ply, name, length_type, value_type);
    else 
        return ply_add_scalar_property(ply, name, type);
}

int ply_add_comment(p_ply ply, const char *comment) {
    char *new_comment = NULL;
    assert(ply && comment && strlen(comment) < LINESIZE);
    if (!comment || strlen(comment) >= LINESIZE) {
        ply_ferror(ply, "Invalid arguments");
        return 0;
    }
    new_comment = (char *) ply_grow_array(ply, (void **) &ply->comment,
            &ply->ncomments, LINESIZE);
    if (!new_comment) return 0;
    strcpy(new_comment, comment);
    return 1;
}

int ply_add_obj_info(p_ply ply, const char *obj_info) {
    char *new_obj_info = NULL;
    assert(ply && obj_info && strlen(obj_info) < LINESIZE);
    if (!obj_info || strlen(obj_info) >= LINESIZE) {
        ply_ferror(ply, "Invalid arguments");
        return 0;
    }
    new_obj_info = (char *) ply_grow_array(ply, (void **) &ply->obj_info,
            &ply->nobj_infos, LINESIZE);
    if (!new_obj_info) return 0;
    strcpy(new_obj_info, obj_info);
    return 1;
}

int ply_write_header(p_ply ply) {
    long i, j;
    assert(ply && ply->fp && ply->io_mode == PLY_WRITE);
    assert(ply->element || ply->nelements == 0); 
    assert(!ply->element || ply->nelements > 0); 
    if (fprintf(ply->fp, "ply\nformat %s 1.0\n", 
                ply_storage_mode_list[ply->storage_mode]) <= 0) goto error;
    for (i = 0; i < ply->ncomments; i++)
        if (fprintf(ply->fp, "comment %s\n", ply->comment + LINESIZE*i) <= 0)
            goto error;
    for (i = 0; i < ply->nobj_infos; i++)
        if (fprintf(ply->fp, "obj_info %s\n", ply->obj_info + LINESIZE*i) <= 0)
            goto error;
    for (i = 0; i < ply->nelements; i++) {
        p_ply_element element = &ply->element[i];
        assert(element->property || element->nproperties == 0); 
        assert(!element->property || element->nproperties > 0); 
        if (fprintf(ply->fp, "element %s %ld\n", element->name, 
                    element->ninstances) <= 0) goto error;
        for (j = 0; j < element->nproperties; j++) {
            p_ply_property property = &element->property[j];
            if (property->type == PLY_LIST) {
                if (fprintf(ply->fp, "property list %s %s %s\n", 
                            ply_type_list[property->length_type],
                            ply_type_list[property->value_type],
                            property->name) <= 0) goto error;
            } else {
                if (fprintf(ply->fp, "property %s %s\n", 
                            ply_type_list[property->type],
                            property->name) <= 0) goto error;
            }
        }
    }
    return fprintf(ply->fp, "end_header\n") > 0;
error:
    ply_ferror(ply, "Error writing to file");
    return 0;
}

int ply_write(p_ply ply, double value) {
    p_ply_element element = NULL;
    p_ply_property property = NULL;
    int type = -1;
    int breakafter = 0;
    int spaceafter = 1;
    if (ply->welement > ply->nelements) return 0;
    element = &ply->element[ply->welement];
    if (ply->wproperty > element->nproperties) return 0;
    property = &element->property[ply->wproperty];
    if (property->type == PLY_LIST) {
        if (ply->wvalue_index == 0) {
            type = property->length_type;
            ply->wlength = (long) value;
        } else type = property->value_type;
    } else {
        type = property->type;
        ply->wlength = 0;
    }
    if (!ply->odriver->ohandler[type](ply, value)) {
        ply_ferror(ply, "Failed writing %s of %s %d (%s: %s)", 
                    property->name, element->name, 
                    ply->winstance_index, 
                    ply->odriver->name, ply_type_list[type]);
        return 0;
    }
    ply->wvalue_index++;
    if (ply->wvalue_index > ply->wlength) {
        ply->wvalue_index = 0;
        ply->wproperty++;
    }
    if (ply->wproperty >= element->nproperties) {
        ply->wproperty = 0;
        ply->winstance_index++;
        breakafter = 1;
        spaceafter = 0;
    }
    if (ply->winstance_index >= element->ninstances) {
        ply->winstance_index = 0;
        do {
            ply->welement++;
            element = &ply->element[ply->welement];
        } while (ply->welement < ply->nelements && !element->ninstances);
    }
    if (ply->storage_mode == PLY_ASCII) {
        return (!spaceafter || putc(' ', ply->fp) > 0) && 
               (!breakafter || putc('\n', ply->fp) > 0);
    } else { 
        return 1;
    }
}

int ply_close(p_ply ply) {
    long i;
    assert(ply && ply->fp);
    assert(ply->element || ply->nelements == 0);
    assert(!ply->element || ply->nelements > 0);
    /* write last chunk to file */
    if (ply->io_mode == PLY_WRITE && 
      fwrite(ply->buffer, 1, ply->buffer_last, ply->fp) < ply->buffer_last) {
        ply_ferror(ply, "Error closing up");
        return 0;
    }
    fclose(ply->fp);
    /* free all memory used by handle */
    if (ply->element) {
        for (i = 0; i < ply->nelements; i++) {
            p_ply_element element = &ply->element[i];
            if (element->property) free(element->property);
        }
        free(ply->element);
    }
    if (ply->obj_info) free(ply->obj_info);
    if (ply->comment) free(ply->comment);
    free(ply);
    return 1;
}

/* ----------------------------------------------------------------------
 * Query support functions
 * ---------------------------------------------------------------------- */
p_ply_element ply_get_next_element(p_ply ply, 
        p_ply_element last) {
    assert(ply);
    if (!last) return ply->element;
    last++;
    if (last < ply->element + ply->nelements) return last;
    else return NULL;
}

int ply_get_element_info(p_ply_element element, const char** name,
        long *ninstances) {
    assert(element);
    if (name) *name = element->name;
    if (ninstances) *ninstances = (long) element->ninstances;
    return 1;
}

p_ply_property ply_get_next_property(p_ply_element element, 
        p_ply_property last) {
    assert(element);
    if (!last) return element->property;
    last++;
    if (last < element->property + element->nproperties) return last;
    else return NULL;
}

int ply_get_property_info(p_ply_property property, const char** name,
        e_ply_type *type, e_ply_type *length_type, e_ply_type *value_type) {
    assert(property);
    if (name) *name = property->name;
    if (type) *type = property->type;
    if (length_type) *length_type = property->length_type;
    if (value_type) *value_type = property->value_type;
    return 1;

}

const char *ply_get_next_comment(p_ply ply, const char *last) {
    assert(ply);
    if (!last) return ply->comment; 
    last += LINESIZE;
    if (last < ply->comment + LINESIZE*ply->ncomments) return last;
    else return NULL;
}

const char *ply_get_next_obj_info(p_ply ply, const char *last) {
    assert(ply);
    if (!last) return ply->obj_info; 
    last += LINESIZE;
    if (last < ply->obj_info + LINESIZE*ply->nobj_infos) return last;
    else return NULL;
}

/* ----------------------------------------------------------------------
 * Callback argument support functions 
 * ---------------------------------------------------------------------- */
int ply_get_argument_element(p_ply_argument argument, 
        p_ply_element *element, long *instance_index) {
    assert(argument);
    if (!argument) return 0;
    if (element) *element = argument->element;
    if (instance_index) *instance_index = argument->instance_index;
    return 1;
}

int ply_get_argument_property(p_ply_argument argument, 
        p_ply_property *property, long *length, long *value_index) {
    assert(argument);
    if (!argument) return 0;
    if (property) *property = argument->property;
    if (length) *length = argument->length;
    if (value_index) *value_index = argument->value_index;
    return 1;
}

int ply_get_argument_user_data(p_ply_argument argument, void **pdata, 
        long *idata) {
    assert(argument);
    if (!argument) return 0;
    if (pdata) *pdata = argument->pdata;
    if (idata) *idata = argument->idata;
    return 1;
}

double ply_get_argument_value(p_ply_argument argument) {
    assert(argument);
    if (!argument) return 0.0;
    return argument->value;
}

int ply_get_ply_user_data(p_ply ply, void **pdata, long *idata) {
    assert(ply);
    if (!ply) return 0;
    if (pdata) *pdata = ply->pdata;
    if (idata) *idata = ply->idata;
    return 1;
}

/* ----------------------------------------------------------------------
 * Internal functions
 * ---------------------------------------------------------------------- */
static int ply_read_list_property(p_ply ply, p_ply_element element, 
        p_ply_property property, p_ply_argument argument) {
    int l;
    p_ply_read_cb read_cb = property->read_cb;
    p_ply_ihandler *driver = ply->idriver->ihandler; 
    /* get list length */
    p_ply_ihandler handler = driver[property->length_type];
    double length;
    if (!handler(ply, &length)) {
        ply_ferror(ply, "Error reading '%s' of '%s' number %d",
                property->name, element->name, argument->instance_index);
        return 0;
    }
    /* invoke callback to pass length in value field */
    argument->length = (long) length;
    argument->value_index = -1;
    argument->value = length;
    if (read_cb && !read_cb(argument)) {
        ply_ferror(ply, "Aborted by user");
        return 0;
    }
    /* read list values */
    handler = driver[property->value_type];
    /* for each value in list */
    for (l = 0; l < (long) length; l++) {
        /* read value from file */
        argument->value_index = l;
        if (!handler(ply, &argument->value)) {
            ply_ferror(ply, "Error reading value number %d of '%s' of "
                    "'%s' number %d", l+1, property->name, 
                    element->name, argument->instance_index);
            return 0;
        }
        /* invoke callback to pass value */
        if (read_cb && !read_cb(argument)) {
            ply_ferror(ply, "Aborted by user");
            return 0;
        }
    }
    return 1;
}

static int ply_read_scalar_property(p_ply ply, p_ply_element element, 
        p_ply_property property, p_ply_argument argument) {
    p_ply_read_cb read_cb = property->read_cb;
    p_ply_ihandler *driver = ply->idriver->ihandler; 
    p_ply_ihandler handler = driver[property->type];
    argument->length = 1;
    argument->value_index = 0;
    if (!handler(ply, &argument->value)) {
        ply_ferror(ply, "Error reading '%s' of '%s' number %d",
                property->name, element->name, argument->instance_index);
        return 0;
    }
    if (read_cb && !read_cb(argument)) {
        ply_ferror(ply, "Aborted by user");
        return 0;
    }
    return 1;
}

static int ply_read_property(p_ply ply, p_ply_element element, 
        p_ply_property property, p_ply_argument argument) {
    if (property->type == PLY_LIST) 
        return ply_read_list_property(ply, element, property, argument);
    else 
        return ply_read_scalar_property(ply, element, property, argument);
}

static int ply_read_element(p_ply ply, p_ply_element element, 
        p_ply_argument argument) {
    long j, k;
    /* for each element of this type */
    for (j = 0; j < element->ninstances; j++) {
        argument->instance_index = j;
        /* for each property */
        for (k = 0; k < element->nproperties; k++) {
            p_ply_property property = &element->property[k];
            argument->property = property;
            argument->pdata = property->pdata;
            argument->idata = property->idata;
            if (!ply_read_property(ply, element, property, argument))
                return 0;
        }
    }
    return 1;
}

static int ply_find_string(const char *item, const char* const list[]) {
    int i;
    assert(item && list);
    for (i = 0; list[i]; i++) 
        if (!strcmp(list[i], item)) return i;
    return -1;
}

static p_ply_element ply_find_element(p_ply ply, const char *name) {
    p_ply_element element;
    int i, nelements;
    assert(ply && name); 
    element = ply->element;
    nelements = ply->nelements;
    assert(element || nelements == 0); 
    assert(!element || nelements > 0); 
    for (i = 0; i < nelements; i++) 
        if (!strcmp(element[i].name, name)) return &element[i];
    return NULL;
}

static p_ply_property ply_find_property(p_ply_element element, 
        const char *name) {
    p_ply_property property;
    int i, nproperties;
    assert(element && name); 
    property = element->property;
    nproperties = element->nproperties;
    assert(property || nproperties == 0); 
    assert(!property || nproperties > 0); 
    for (i = 0; i < nproperties; i++) 
        if (!strcmp(property[i].name, name)) return &property[i];
    return NULL;
}

static int ply_check_word(p_ply ply) {
    size_t size = strlen(BWORD(ply));
    if (size >= WORDSIZE) {
        ply_ferror(ply, "Word too long");
        return 0;
    } else if (size == 0) {
        ply_ferror(ply, "Unexpected end of file");
        return 0;
    }
    return 1;
}

static int ply_read_word(p_ply ply) {
    size_t t = 0;
    assert(ply && ply->fp && ply->io_mode == PLY_READ);
    /* skip leading blanks */
    while (1) {
        t = strspn(BFIRST(ply), " \n\r\t");
        /* check if all buffer was made of blanks */
        if (t >= BSIZE(ply)) {
            if (!BREFILL(ply)) {
                ply_ferror(ply, "Unexpected end of file");
                return 0;
            }
        } else break; 
    } 
    BSKIP(ply, t); 
    /* look for a space after the current word */
    t = strcspn(BFIRST(ply), " \n\r\t");
    /* if we didn't reach the end of the buffer, we are done */
    if (t < BSIZE(ply)) {
        ply_finish_word(ply, t);
        return ply_check_word(ply);
    }
    /* otherwise, try to refill buffer */
    if (!BREFILL(ply)) {
        /* if we reached the end of file, try to do with what we have */
        ply_finish_word(ply, t);
        return ply_check_word(ply);
        /* ply_ferror(ply, "Unexpected end of file"); */
        /* return 0; */
    }
    /* keep looking from where we left */
    t += strcspn(BFIRST(ply) + t, " \n\r\t");
    /* check if the token is too large for our buffer */
    if (t >= BSIZE(ply)) {
        ply_ferror(ply, "Token too large");
        return 0;
    }
    /* we are done */
    ply_finish_word(ply, t);
    return ply_check_word(ply);
}

static void ply_finish_word(p_ply ply, size_t size) {
    ply->buffer_token = ply->buffer_first;
    BSKIP(ply, size);
    *BFIRST(ply) = '\0';
    BSKIP(ply, 1);
}

static int ply_check_line(p_ply ply) {
    if (strlen(BLINE(ply)) >= LINESIZE) {
        ply_ferror(ply, "Line too long");
        return 0;
    }
    return 1;
}

static int ply_read_line(p_ply ply) {
    const char *end = NULL;
    assert(ply && ply->fp && ply->io_mode == PLY_READ);
    /* look for a end of line */
    end = strchr(BFIRST(ply), '\n');
    /* if we didn't reach the end of the buffer, we are done */
    if (end) {
        ply->buffer_token = ply->buffer_first;
        BSKIP(ply, end - BFIRST(ply));
        *BFIRST(ply) = '\0';
        BSKIP(ply, 1);
        return ply_check_line(ply);
    } else {
        end = ply->buffer + BSIZE(ply); 
        /* otherwise, try to refill buffer */
        if (!BREFILL(ply)) {
            ply_ferror(ply, "Unexpected end of file");
            return 0;
        }
    }
    /* keep looking from where we left */
    end = strchr(end, '\n');
    /* check if the token is too large for our buffer */
    if (!end) {
        ply_ferror(ply, "Token too large");
        return 0;
    }
    /* we are done */
    ply->buffer_token = ply->buffer_first;
    BSKIP(ply, end - BFIRST(ply));
    *BFIRST(ply) = '\0';
    BSKIP(ply, 1);
    return ply_check_line(ply);
}

static int ply_read_chunk(p_ply ply, void *anybuffer, size_t size) {
    char *buffer = (char *) anybuffer;
    size_t i = 0;
    assert(ply && ply->fp && ply->io_mode == PLY_READ);
    assert(ply->buffer_first <= ply->buffer_last);
    while (i < size) {
        if (ply->buffer_first < ply->buffer_last) {
            buffer[i] = ply->buffer[ply->buffer_first];
            ply->buffer_first++;
            i++;
        } else {
            ply->buffer_first = 0;
            ply->buffer_last = fread(ply->buffer, 1, BUFFERSIZE, ply->fp);
            if (ply->buffer_last <= 0) return 0;
        }
    }
    return 1;
}

static int ply_write_chunk(p_ply ply, void *anybuffer, size_t size) {
    char *buffer = (char *) anybuffer;
    size_t i = 0;
    assert(ply && ply->fp && ply->io_mode == PLY_WRITE);
    assert(ply->buffer_last <= BUFFERSIZE);
    while (i < size) {
        if (ply->buffer_last < BUFFERSIZE) {
            ply->buffer[ply->buffer_last] = buffer[i];
            ply->buffer_last++;
            i++;
        } else {
            ply->buffer_last = 0;
            if (fwrite(ply->buffer, 1, BUFFERSIZE, ply->fp) < BUFFERSIZE)
                return 0;
        }
    }
    return 1;
}

static int ply_write_chunk_reverse(p_ply ply, void *anybuffer, size_t size) {
    int ret = 0;
    ply_reverse(anybuffer, size);
    ret = ply_write_chunk(ply, anybuffer, size);
    ply_reverse(anybuffer, size);
    return ret;
}

static int ply_read_chunk_reverse(p_ply ply, void *anybuffer, size_t size) {
    if (!ply_read_chunk(ply, anybuffer, size)) return 0;
    ply_reverse(anybuffer, size);
    return 1;
}

static void ply_reverse(void *anydata, size_t size) {
    char *data = (char *) anydata;
    char temp;
    size_t i;
    for (i = 0; i < size/2; i++) {
        temp = data[i];
        data[i] = data[size-i-1];
        data[size-i-1] = temp;
    }
}

static void ply_init(p_ply ply) {
    ply->element = NULL;
    ply->nelements = 0;
    ply->comment = NULL;
    ply->ncomments = 0;
    ply->obj_info = NULL;
    ply->nobj_infos = 0;
    ply->idriver = NULL;
    ply->odriver = NULL;
    ply->buffer[0] = '\0';
    ply->buffer_first = ply->buffer_last = ply->buffer_token = 0;
    ply->welement = 0;
    ply->wproperty = 0;
    ply->winstance_index = 0;
    ply->wlength = 0;
    ply->wvalue_index = 0;
}

static void ply_element_init(p_ply_element element) {
    element->name[0] = '\0';
    element->ninstances = 0;
    element->property = NULL;
    element->nproperties = 0; 
}

static void ply_property_init(p_ply_property property) {
    property->name[0] = '\0';
    property->type = (e_ply_type)-1;
    property->length_type = (e_ply_type)-1;
    property->value_type = (e_ply_type)-1;
    property->read_cb = (p_ply_read_cb) NULL;
    property->pdata = NULL;
    property->idata = 0;
}

static p_ply ply_alloc(void) {
    p_ply ply = (p_ply) calloc(1, sizeof(t_ply));
    if (!ply) return NULL;
    ply_init(ply);
    return ply;
}

static void *ply_grow_array(p_ply ply, void **pointer, 
        long *nmemb, long size) {
    void *temp = *pointer;
    long count = *nmemb + 1;
    if (!temp) temp = malloc(count*size);
    else temp = realloc(temp, count*size);
    if (!temp) {
        ply_ferror(ply, "Out of memory");
        return NULL;
    }
    *pointer = temp;
    *nmemb = count;
    return (char *) temp + (count-1) * size;
}

static p_ply_element ply_grow_element(p_ply ply) {
    p_ply_element element = NULL;
    assert(ply); 
    assert(ply->element || ply->nelements == 0); 
    assert(!ply->element || ply->nelements > 0); 
    element = (p_ply_element) ply_grow_array(ply, (void **) &ply->element, 
            &ply->nelements, sizeof(t_ply_element));
    if (!element) return NULL;
    ply_element_init(element);
    return element; 
}

static p_ply_property ply_grow_property(p_ply ply, p_ply_element element) {
    p_ply_property property = NULL;
    assert(ply);
    assert(element);
    assert(element->property || element->nproperties == 0);
    assert(!element->property || element->nproperties > 0);
    property = (p_ply_property) ply_grow_array(ply, 
            (void **) &element->property, 
            &element->nproperties, sizeof(t_ply_property));
    if (!property) return NULL;
    ply_property_init(property);
    return property;
}


static int ply_read_header_comment(p_ply ply) {
    assert(ply && ply->fp && ply->io_mode == PLY_READ);
    if (strcmp(BWORD(ply), "comment")) return 0;
    if (!ply_read_line(ply)) return 0;
    if (!ply_add_comment(ply, BLINE(ply))) return 0;
    if (!ply_read_word(ply)) return 0;
    return 1;
}

static int ply_read_header_obj_info(p_ply ply) {
    assert(ply && ply->fp && ply->io_mode == PLY_READ);
    if (strcmp(BWORD(ply), "obj_info")) return 0;
    if (!ply_read_line(ply)) return 0;
    if (!ply_add_obj_info(ply, BLINE(ply))) return 0;
    if (!ply_read_word(ply)) return 0;
    return 1;
}

static int ply_read_header_property(p_ply ply) {
    p_ply_element element = NULL;
    p_ply_property property = NULL;
    /* make sure it is a property */
    if (strcmp(BWORD(ply), "property")) return 0;
    element = &ply->element[ply->nelements-1];
    property = ply_grow_property(ply, element);
    if (!property) return 0;
    /* get property type */
    if (!ply_read_word(ply)) return 0;
    property->type = (e_ply_type)ply_find_string(BWORD(ply), ply_type_list);
    if (property->type == (e_ply_type) (-1)) return 0;
    if (property->type == PLY_LIST) {
        /* if it's a list, we need the base types */
        if (!ply_read_word(ply)) return 0;
        property->length_type = (e_ply_type)ply_find_string(BWORD(ply), ply_type_list);
        if (property->length_type == (e_ply_type) (-1)) return 0;
        if (!ply_read_word(ply)) return 0;
        property->value_type = (e_ply_type)ply_find_string(BWORD(ply), ply_type_list);
        if (property->value_type == (e_ply_type) (-1)) return 0;
    }
    /* get property name */
    if (!ply_read_word(ply)) return 0;
    strcpy(property->name, BWORD(ply));
    if (!ply_read_word(ply)) return 0;
    return 1;
}

static int ply_read_header_element(p_ply ply) {
    p_ply_element element = NULL;
    long dummy;
    assert(ply && ply->fp && ply->io_mode == PLY_READ);
    if (strcmp(BWORD(ply), "element")) return 0;
    /* allocate room for new element */
    element = ply_grow_element(ply);
    if (!element) return 0;
    /* get element name */
    if (!ply_read_word(ply)) return 0;
    strcpy(element->name, BWORD(ply));
    /* get number of elements of this type */
    if (!ply_read_word(ply)) return 0;
    if (sscanf(BWORD(ply), "%ld", &dummy) != 1) {
        ply_ferror(ply, "Expected number got '%s'", BWORD(ply));
        return 0;
    }
    element->ninstances = dummy;
    /* get all properties for this element */
    if (!ply_read_word(ply)) return 0;
    while (ply_read_header_property(ply) || 
        ply_read_header_comment(ply) || ply_read_header_obj_info(ply))
        /* do nothing */;
    return 1;
}

static void ply_error_cb(p_ply ply, const char *message) {
    (void) ply;
    fprintf(stderr, "RPly: %s\n", message);
}

static void ply_ferror(p_ply ply, const char *fmt, ...) {
    char buffer[1024];
    va_list ap;
    va_start(ap, fmt);
    vsprintf(buffer, fmt, ap);
    va_end(ap);
    ply->error_cb(ply, buffer);
}

static e_ply_storage_mode ply_arch_endian(void) {
    unsigned long i = 1;
    unsigned char *s = (unsigned char *) &i;
    if (*s == 1) return PLY_LITTLE_ENDIAN;
    else return PLY_BIG_ENDIAN;
}

static int ply_type_check(void) {
    assert(sizeof(t_ply_int8) == 1);
    assert(sizeof(t_ply_uint8) == 1);
    assert(sizeof(t_ply_int16) == 2);
    assert(sizeof(t_ply_uint16) == 2);
    assert(sizeof(t_ply_int32) == 4);
    assert(sizeof(t_ply_uint32) == 4);
    assert(sizeof(float) == 4);
    assert(sizeof(double) == 8);
    if (sizeof(t_ply_int8) != 1) return 0;
    if (sizeof(t_ply_uint8) != 1) return 0;
    if (sizeof(t_ply_int16) != 2) return 0;
    if (sizeof(t_ply_uint16) != 2) return 0;
    if (sizeof(t_ply_int32) != 4) return 0;
    if (sizeof(t_ply_uint32) != 4) return 0;
    if (sizeof(float) != 4) return 0;
    if (sizeof(double) != 8) return 0;
    return 1;
}

/* ----------------------------------------------------------------------
 * Output handlers
 * ---------------------------------------------------------------------- */
static int oascii_int8(p_ply ply, double value) {
    if (value > PLY_INT8_MAX || value < PLY_INT8_MIN) return 0;
    return fprintf(ply->fp, "%d", (t_ply_int8) value) > 0;
}

static int oascii_uint8(p_ply ply, double value) {
    if (value > PLY_UINT8_MAX || value < 0) return 0;
    return fprintf(ply->fp, "%d", (t_ply_uint8) value) > 0;
}

static int oascii_int16(p_ply ply, double value) {
    if (value > PLY_INT16_MAX || value < PLY_INT16_MIN) return 0;
    return fprintf(ply->fp, "%d", (t_ply_int16) value) > 0;
}

static int oascii_uint16(p_ply ply, double value) {
    if (value > PLY_UINT16_MAX || value < 0) return 0;
    return fprintf(ply->fp, "%d", (t_ply_uint16) value) > 0;
}

static int oascii_int32(p_ply ply, double value) {
    if (value > PLY_INT32_MAX || value < PLY_INT32_MIN) return 0;
    return fprintf(ply->fp, "%d", (t_ply_int32) value) > 0;
}

static int oascii_uint32(p_ply ply, double value) {
    if (value > PLY_UINT32_MAX || value < 0) return 0;
    return fprintf(ply->fp, "%d", (t_ply_uint32) value) > 0;
}

static int oascii_float32(p_ply ply, double value) {
    if (value < -FLT_MAX || value > FLT_MAX) return 0;
    return fprintf(ply->fp, "%g", (float) value) > 0;
}

static int oascii_float64(p_ply ply, double value) {
    if (value < -DBL_MAX || value > DBL_MAX) return 0;
    return fprintf(ply->fp, "%g", value) > 0;
}

static int obinary_int8(p_ply ply, double value) {
    t_ply_int8 int8 = (t_ply_int8) value;
    if (value > PLY_INT8_MAX || value < PLY_INT8_MIN) return 0;
    return ply->odriver->ochunk(ply, &int8, sizeof(int8));
}

static int obinary_uint8(p_ply ply, double value) {
    t_ply_uint8 uint8 = (t_ply_uint8) value;
    if (value > PLY_UINT8_MAX || value < 0) return 0;
    return ply->odriver->ochunk(ply, &uint8, sizeof(uint8)); 
}

static int obinary_int16(p_ply ply, double value) {
    t_ply_int16 int16 = (t_ply_int16) value;
    if (value > PLY_INT16_MAX || value < PLY_INT16_MIN) return 0;
    return ply->odriver->ochunk(ply, &int16, sizeof(int16));
}

static int obinary_uint16(p_ply ply, double value) {
    t_ply_uint16 uint16 = (t_ply_uint16) value;
    if (value > PLY_UINT16_MAX || value < 0) return 0;
    return ply->odriver->ochunk(ply, &uint16, sizeof(uint16)); 
}

static int obinary_int32(p_ply ply, double value) {
    t_ply_int32 int32 = (t_ply_int32) value;
    if (value > PLY_INT32_MAX || value < PLY_INT32_MIN) return 0;
    return ply->odriver->ochunk(ply, &int32, sizeof(int32));
}

static int obinary_uint32(p_ply ply, double value) {
    t_ply_uint32 uint32 = (t_ply_uint32) value;
    if (value > PLY_UINT32_MAX || value < 0) return 0;
    return ply->odriver->ochunk(ply, &uint32, sizeof(uint32));
}

static int obinary_float32(p_ply ply, double value) {
    float float32 = (float) value;
    if (value > FLT_MAX || value < -FLT_MAX) return 0;
    return ply->odriver->ochunk(ply, &float32, sizeof(float32));
}

static int obinary_float64(p_ply ply, double value) {
    return ply->odriver->ochunk(ply, &value, sizeof(value)); 
}

/* ----------------------------------------------------------------------
 * Input  handlers
 * ---------------------------------------------------------------------- */
static int iascii_int8(p_ply ply, double *value) {
    char *end;
    if (!ply_read_word(ply)) return 0;
    *value = strtol(BWORD(ply), &end, 10);
    if (*end || *value > PLY_INT8_MAX || *value < PLY_INT8_MIN) return 0;
    return 1;
}

static int iascii_uint8(p_ply ply, double *value) {
    char *end;
    if (!ply_read_word(ply)) return 0;
    *value = strtol(BWORD(ply), &end, 10);
    if (*end || *value > PLY_UINT8_MAX || *value < 0) return 0;
    return 1;
}

static int iascii_int16(p_ply ply, double *value) {
    char *end;
    if (!ply_read_word(ply)) return 0;
    *value = strtol(BWORD(ply), &end, 10);
    if (*end || *value > PLY_INT16_MAX || *value < PLY_INT16_MIN) return 0;
    return 1;
}

static int iascii_uint16(p_ply ply, double *value) {
    char *end;
    if (!ply_read_word(ply)) return 0;
    *value = strtol(BWORD(ply), &end, 10);
    if (*end || *value > PLY_UINT16_MAX || *value < 0) return 0;
    return 1;
}

static int iascii_int32(p_ply ply, double *value) {
    char *end;
    if (!ply_read_word(ply)) return 0;
    *value = strtol(BWORD(ply), &end, 10);
    if (*end || *value > PLY_INT32_MAX || *value < PLY_INT32_MIN) return 0;
    return 1;
}

static int iascii_uint32(p_ply ply, double *value) {
    char *end;
    if (!ply_read_word(ply)) return 0;
    *value = strtol(BWORD(ply), &end, 10);
    if (*end || *value > PLY_UINT32_MAX || *value < 0) return 0;
    return 1;
}

static int iascii_float32(p_ply ply, double *value) {
    char *end;
    if (!ply_read_word(ply)) return 0;
    *value = strtod(BWORD(ply), &end);
    if (*end || *value < -FLT_MAX || *value > FLT_MAX) return 0;
    return 1;
}

static int iascii_float64(p_ply ply, double *value) {
    char *end;
    if (!ply_read_word(ply)) return 0;
    *value = strtod(BWORD(ply), &end);
    if (*end || *value < -DBL_MAX || *value > DBL_MAX) return 0;
    return 1;
}

static int ibinary_int8(p_ply ply, double *value) {
    t_ply_int8 int8;
    if (!ply->idriver->ichunk(ply, &int8, 1)) return 0;
    *value = int8;
    return 1;
}

static int ibinary_uint8(p_ply ply, double *value) {
    t_ply_uint8 uint8;
    if (!ply->idriver->ichunk(ply, &uint8, 1)) return 0;
    *value = uint8;
    return 1;
}

static int ibinary_int16(p_ply ply, double *value) {
    t_ply_int16 int16;
    if (!ply->idriver->ichunk(ply, &int16, sizeof(int16))) return 0;
    *value = int16;
    return 1;
}

static int ibinary_uint16(p_ply ply, double *value) {
    t_ply_uint16 uint16;
    if (!ply->idriver->ichunk(ply, &uint16, sizeof(uint16))) return 0;
    *value = uint16;
    return 1;
}

static int ibinary_int32(p_ply ply, double *value) {
    t_ply_int32 int32;
    if (!ply->idriver->ichunk(ply, &int32, sizeof(int32))) return 0;
    *value = int32;
    return 1;
}

static int ibinary_uint32(p_ply ply, double *value) {
    t_ply_uint32 uint32;
    if (!ply->idriver->ichunk(ply, &uint32, sizeof(uint32))) return 0;
    *value = uint32;
    return 1;
}

static int ibinary_float32(p_ply ply, double *value) {
    float float32;
    if (!ply->idriver->ichunk(ply, &float32, sizeof(float32))) return 0;
    *value = float32;
    return 1;
}

static int ibinary_float64(p_ply ply, double *value) {
    return ply->idriver->ichunk(ply, value, sizeof(double));
}

/* ----------------------------------------------------------------------
 * Constants
 * ---------------------------------------------------------------------- */
static t_ply_idriver ply_idriver_ascii = {
    {   iascii_int8, iascii_uint8, iascii_int16, iascii_uint16,
        iascii_int32, iascii_uint32, iascii_float32, iascii_float64,
        iascii_int8, iascii_uint8, iascii_int16, iascii_uint16,
        iascii_int32, iascii_uint32, iascii_float32, iascii_float64
    }, /* order matches e_ply_type enum */
    NULL,
    "ascii input"
};

static t_ply_idriver ply_idriver_binary = {
    {   ibinary_int8, ibinary_uint8, ibinary_int16, ibinary_uint16,
        ibinary_int32, ibinary_uint32, ibinary_float32, ibinary_float64,
        ibinary_int8, ibinary_uint8, ibinary_int16, ibinary_uint16,
        ibinary_int32, ibinary_uint32, ibinary_float32, ibinary_float64
    }, /* order matches e_ply_type enum */
    ply_read_chunk,
    "binary input"
};

static t_ply_idriver ply_idriver_binary_reverse = {
    {   ibinary_int8, ibinary_uint8, ibinary_int16, ibinary_uint16,
        ibinary_int32, ibinary_uint32, ibinary_float32, ibinary_float64,
        ibinary_int8, ibinary_uint8, ibinary_int16, ibinary_uint16,
        ibinary_int32, ibinary_uint32, ibinary_float32, ibinary_float64
    }, /* order matches e_ply_type enum */
    ply_read_chunk_reverse,
    "reverse binary input"
};

static t_ply_odriver ply_odriver_ascii = {
    {   oascii_int8, oascii_uint8, oascii_int16, oascii_uint16,
        oascii_int32, oascii_uint32, oascii_float32, oascii_float64,
        oascii_int8, oascii_uint8, oascii_int16, oascii_uint16,
        oascii_int32, oascii_uint32, oascii_float32, oascii_float64
    }, /* order matches e_ply_type enum */
    NULL,
    "ascii output"
};

static t_ply_odriver ply_odriver_binary = {
    {   obinary_int8, obinary_uint8, obinary_int16, obinary_uint16,
        obinary_int32, obinary_uint32, obinary_float32, obinary_float64,
        obinary_int8, obinary_uint8, obinary_int16, obinary_uint16,
        obinary_int32, obinary_uint32, obinary_float32, obinary_float64
    }, /* order matches e_ply_type enum */
    ply_write_chunk,
    "binary output"
};

static t_ply_odriver ply_odriver_binary_reverse = {
    {   obinary_int8, obinary_uint8, obinary_int16, obinary_uint16,
        obinary_int32, obinary_uint32, obinary_float32, obinary_float64,
        obinary_int8, obinary_uint8, obinary_int16, obinary_uint16,
        obinary_int32, obinary_uint32, obinary_float32, obinary_float64
    }, /* order matches e_ply_type enum */
    ply_write_chunk_reverse,
    "reverse binary output"
};

static int ply_read_header_format(p_ply ply) {
    assert(ply && ply->fp && ply->io_mode == PLY_READ);
    if (strcmp(BWORD(ply), "format")) return 0;
    if (!ply_read_word(ply)) return 0;
    ply->storage_mode = (e_ply_storage_mode)ply_find_string(BWORD(ply), ply_storage_mode_list);
    if (ply->storage_mode == (e_ply_storage_mode) (-1)) return 0;
    if (ply->storage_mode == PLY_ASCII) ply->idriver = &ply_idriver_ascii;
    else if (ply->storage_mode == ply_arch_endian()) 
        ply->idriver = &ply_idriver_binary;
    else ply->idriver = &ply_idriver_binary_reverse;
    if (!ply_read_word(ply)) return 0;
    if (strcmp(BWORD(ply), "1.0")) return 0;
    if (!ply_read_word(ply)) return 0;
    return 1;
}

p_ply ply_create(const char *name, e_ply_storage_mode storage_mode, 
        p_ply_error_cb error_cb, long idata, void *pdata) {
    FILE *fp = NULL;
    p_ply ply = ply_alloc();
    if (error_cb == NULL) error_cb = ply_error_cb;
    if (!ply) {
        error_cb(NULL, "Out of memory");
        return NULL;
    }
    if (!ply_type_check()) {
        error_cb(ply, "Incompatible type system");
        free(ply);
        return NULL;
    }
    assert(name && storage_mode <= PLY_DEFAULT);
    fp = fopen(name, "wb");
    if (!fp) {
        error_cb(ply, "Unable to create file");
        free(ply);
        return NULL;
    }
    ply->idata = idata;
    ply->pdata = pdata;
    ply->io_mode = PLY_WRITE;
    if (storage_mode == PLY_DEFAULT) storage_mode = ply_arch_endian();
    if (storage_mode == PLY_ASCII) ply->odriver = &ply_odriver_ascii;
    else if (storage_mode == ply_arch_endian()) 
        ply->odriver = &ply_odriver_binary;
    else ply->odriver = &ply_odriver_binary_reverse;
    ply->storage_mode = storage_mode;
    ply->fp = fp;
    ply->error_cb = error_cb;
    return ply;
}



/* ----------------------------------------------------------------------
 * Copyright (C) 2003-2011 Diego Nehab.  All rights reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
 * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 * ---------------------------------------------------------------------- */

rply.h

#ifndef RPLY_H
#define RPLY_H
/* ----------------------------------------------------------------------
 * RPly library, read/write PLY files
 * Diego Nehab, IMPA
 * http://www.impa.br/~diego/software/rply
 *
 * This library is distributed under the MIT License. See notice
 * at the end of this file.
 * ---------------------------------------------------------------------- */

#ifdef __cplusplus
extern "C" {
#endif

#define RPLY_VERSION   "RPly 1.1.3"
#define RPLY_COPYRIGHT "Copyright (C) 2003-2013 Diego Nehab"
#define RPLY_AUTHORS   "Diego Nehab"

#include <stdio.h>
#include <ctype.h>
#include <assert.h>
#include <string.h>
#include <limits.h>
#include <float.h>
#include <stdarg.h>
#include <stdlib.h>
#include <stddef.h>


/* ----------------------------------------------------------------------
 * Types
 * ---------------------------------------------------------------------- */
/* structures are opaque */
typedef struct t_ply_ *p_ply;
typedef struct t_ply_element_ *p_ply_element;
typedef struct t_ply_property_ *p_ply_property;
typedef struct t_ply_argument_ *p_ply_argument;

/* ply format mode type */
typedef enum e_ply_storage_mode_ {
    PLY_BIG_ENDIAN,
    PLY_LITTLE_ENDIAN,
    PLY_ASCII,   
    PLY_DEFAULT      /* has to be the last in enum */
} e_ply_storage_mode; /* order matches ply_storage_mode_list */

/* ply data type */
typedef enum e_ply_type {
    PLY_INT8, PLY_UINT8, PLY_INT16, PLY_UINT16, 
    PLY_INT32, PLY_UIN32, PLY_FLOAT32, PLY_FLOAT64,
    PLY_CHAR, PLY_UCHAR, PLY_SHORT, PLY_USHORT,
    PLY_INT, PLY_UINT, PLY_FLOAT, PLY_DOUBLE,
    PLY_LIST    /* has to be the last in enum */
} e_ply_type;   /* order matches ply_type_list */

/* ----------------------------------------------------------------------
 * Error callback prototype
 *
 * message: error message
 * ply: handle returned by ply_open or ply_create
 * ---------------------------------------------------------------------- */
typedef void (*p_ply_error_cb)(p_ply ply, const char *message);

/* ----------------------------------------------------------------------
 * Gets user data from within an error callback 
 *
 * ply: handle returned by ply_open or ply_create
 * idata,pdata: contextual information set in ply_open or ply_create
 * ---------------------------------------------------------------------- */
int ply_get_ply_user_data(p_ply ply, void **pdata, long *idata);

/* ----------------------------------------------------------------------
 * Opens a PLY file for reading (fails if file is not a PLY file)
 *
 * name: file name
 * error_cb: error callback function
 * idata,pdata: contextual information available to users
 *
 * Returns 1 if successful, 0 otherwise
 * ---------------------------------------------------------------------- */
p_ply ply_open(const char *name, p_ply_error_cb error_cb, long idata, 
        void *pdata);

/* ----------------------------------------------------------------------
 * Reads and parses the header of a PLY file returned by ply_open
 *
 * ply: handle returned by ply_open
 *
 * Returns 1 if successfull, 0 otherwise
 * ---------------------------------------------------------------------- */
int ply_read_header(p_ply ply);

/* ----------------------------------------------------------------------
 * Property reading callback prototype
 *
 * argument: parameters for property being processed when callback is called
 *
 * Returns 1 if should continue processing file, 0 if should abort.
 * ---------------------------------------------------------------------- */
typedef int (*p_ply_read_cb)(p_ply_argument argument);

/* ----------------------------------------------------------------------
 * Sets up callbacks for property reading after header was parsed
 *
 * ply: handle returned by ply_open
 * element_name: element where property is
 * property_name: property to associate element with
 * read_cb: function to be called for each property value
 * pdata/idata: user data that will be passed to callback
 *
 * Returns 0 if no element or no property in element, returns the
 * number of element instances otherwise. 
 * ---------------------------------------------------------------------- */
long ply_set_read_cb(p_ply ply, const char *element_name, 
        const char *property_name, p_ply_read_cb read_cb, 
        void *pdata, long idata);

/* ----------------------------------------------------------------------
 * Returns information about the element originating a callback
 *
 * argument: handle to argument 
 * element: receives a the element handle (if non-null)
 * instance_index: receives the index of the current element instance 
 *     (if non-null)
 *
 * Returns 1 if successfull, 0 otherwise
 * ---------------------------------------------------------------------- */
int ply_get_argument_element(p_ply_argument argument, 
        p_ply_element *element, long *instance_index);

/* ----------------------------------------------------------------------
 * Returns information about the property originating a callback
 *
 * argument: handle to argument 
 * property: receives the property handle (if non-null)
 * length: receives the number of values in this property (if non-null)
 * value_index: receives the index of current property value (if non-null)
 *
 * Returns 1 if successfull, 0 otherwise
 * ---------------------------------------------------------------------- */
int ply_get_argument_property(p_ply_argument argument, 
        p_ply_property *property, long *length, long *value_index);

/* ----------------------------------------------------------------------
 * Returns user data associated with callback 
 *
 * pdata: receives a copy of user custom data pointer (if non-null)
 * idata: receives a copy of user custom data integer (if non-null)
 *
 * Returns 1 if successfull, 0 otherwise
 * ---------------------------------------------------------------------- */
int ply_get_argument_user_data(p_ply_argument argument, void **pdata, 
        long *idata);

/* ----------------------------------------------------------------------
 * Returns the value associated with a callback
 *
 * argument: handle to argument 
 *
 * Returns the current data item
 * ---------------------------------------------------------------------- */
double ply_get_argument_value(p_ply_argument argument); 

/* ----------------------------------------------------------------------
 * Reads all elements and properties calling the callbacks defined with
 * calls to ply_set_read_cb
 *
 * ply: handle returned by ply_open
 *
 * Returns 1 if successfull, 0 otherwise
 * ---------------------------------------------------------------------- */
int ply_read(p_ply ply);

/* ----------------------------------------------------------------------
 * Iterates over all elements by returning the next element.
 * Call with NULL to return handle to first element.
 *
 * ply: handle returned by ply_open
 * last: handle of last element returned (NULL for first element)
 *
 * Returns element if successfull or NULL if no more elements
 * ---------------------------------------------------------------------- */
p_ply_element ply_get_next_element(p_ply ply, p_ply_element last);

/* ----------------------------------------------------------------------
 * Iterates over all comments by returning the next comment.
 * Call with NULL to return pointer to first comment.
 *
 * ply: handle returned by ply_open
 * last: pointer to last comment returned (NULL for first comment)
 *
 * Returns comment if successfull or NULL if no more comments
 * ---------------------------------------------------------------------- */
const char *ply_get_next_comment(p_ply ply, const char *last);

/* ----------------------------------------------------------------------
 * Iterates over all obj_infos by returning the next obj_info.
 * Call with NULL to return pointer to first obj_info.
 *
 * ply: handle returned by ply_open
 * last: pointer to last obj_info returned (NULL for first obj_info)
 *
 * Returns obj_info if successfull or NULL if no more obj_infos
 * ---------------------------------------------------------------------- */
const char *ply_get_next_obj_info(p_ply ply, const char *last);

/* ----------------------------------------------------------------------
 * Returns information about an element
 *
 * element: element of interest
 * name: receives a pointer to internal copy of element name (if non-null)
 * ninstances: receives the number of instances of this element (if non-null)
 *
 * Returns 1 if successfull or 0 otherwise
 * ---------------------------------------------------------------------- */
int ply_get_element_info(p_ply_element element, const char** name,
        long *ninstances);

/* ----------------------------------------------------------------------
 * Iterates over all properties by returning the next property.
 * Call with NULL to return handle to first property.
 *
 * element: handle of element with the properties of interest
 * last: handle of last property returned (NULL for first property)
 *
 * Returns element if successfull or NULL if no more properties
 * ---------------------------------------------------------------------- */
p_ply_property ply_get_next_property(p_ply_element element, 
        p_ply_property last);

/* ----------------------------------------------------------------------
 * Returns information about a property
 *
 * property: handle to property of interest
 * name: receives a pointer to internal copy of property name (if non-null)
 * type: receives the property type (if non-null)
 * length_type: for list properties, receives the scalar type of
 *     the length field (if non-null)
 * value_type: for list properties, receives the scalar type of the value 
 *     fields  (if non-null)
 *
 * Returns 1 if successfull or 0 otherwise
 * ---------------------------------------------------------------------- */
int ply_get_property_info(p_ply_property property, const char** name,
        e_ply_type *type, e_ply_type *length_type, e_ply_type *value_type);

/* ----------------------------------------------------------------------
 * Creates new PLY file
 *
 * name: file name
 * storage_mode: file format mode
 *
 * Returns handle to PLY file if successfull, NULL otherwise
 * ---------------------------------------------------------------------- */
p_ply ply_create(const char *name, e_ply_storage_mode storage_mode, 
        p_ply_error_cb error_cb, long idata, void *pdata);

/* ----------------------------------------------------------------------
 * Adds a new element to the PLY file created by ply_create
 *
 * ply: handle returned by ply_create
 * name: name of new element
 * ninstances: number of element of this time in file
 *
 * Returns 1 if successfull, 0 otherwise
 * ---------------------------------------------------------------------- */
int ply_add_element(p_ply ply, const char *name, long ninstances);

/* ----------------------------------------------------------------------
 * Adds a new property to the last element added by ply_add_element
 *
 * ply: handle returned by ply_create
 * name: name of new property
 * type: property type
 * length_type: scalar type of length field of a list property 
 * value_type: scalar type of value fields of a list property
 *
 * Returns 1 if successfull, 0 otherwise
 * ---------------------------------------------------------------------- */
int ply_add_property(p_ply ply, const char *name, e_ply_type type,
        e_ply_type length_type, e_ply_type value_type);

/* ----------------------------------------------------------------------
 * Adds a new list property to the last element added by ply_add_element
 *
 * ply: handle returned by ply_create
 * name: name of new property
 * length_type: scalar type of length field of a list property 
 * value_type: scalar type of value fields of a list property
 *
 * Returns 1 if successfull, 0 otherwise
 * ---------------------------------------------------------------------- */
int ply_add_list_property(p_ply ply, const char *name, 
        e_ply_type length_type, e_ply_type value_type);

/* ----------------------------------------------------------------------
 * Adds a new property to the last element added by ply_add_element
 *
 * ply: handle returned by ply_create
 * name: name of new property
 * type: property type
 *
 * Returns 1 if successfull, 0 otherwise
 * ---------------------------------------------------------------------- */
int ply_add_scalar_property(p_ply ply, const char *name, e_ply_type type);

/* ----------------------------------------------------------------------
 * Adds a new comment item 
 *
 * ply: handle returned by ply_create
 * comment: pointer to string with comment text
 *
 * Returns 1 if successfull, 0 otherwise
 * ---------------------------------------------------------------------- */
int ply_add_comment(p_ply ply, const char *comment);

/* ----------------------------------------------------------------------
 * Adds a new obj_info item 
 *
 * ply: handle returned by ply_create
 * comment: pointer to string with obj_info data
 *
 * Returns 1 if successfull, 0 otherwise
 * ---------------------------------------------------------------------- */
int ply_add_obj_info(p_ply ply, const char *obj_info);

/* ----------------------------------------------------------------------
 * Writes the PLY file header after all element and properties have been
 * defined by calls to ply_add_element and ply_add_property
 *
 * ply: handle returned by ply_create
 *
 * Returns 1 if successfull, 0 otherwise
 * ---------------------------------------------------------------------- */
int ply_write_header(p_ply ply);

/* ----------------------------------------------------------------------
 * Writes one property value, in the order they should be written to the
 * file. For each element type, write all elements of that type in order.
 * For each element, write all its properties in order. For scalar
 * properties, just write the value. For list properties, write the length 
 * and then each of the values.
 *
 * ply: handle returned by ply_create
 *
 * Returns 1 if successfull, 0 otherwise
 * ---------------------------------------------------------------------- */
int ply_write(p_ply ply, double value);

/* ----------------------------------------------------------------------
 * Closes a PLY file handle. Releases all memory used by handle
 *
 * ply: handle to be closed. 
 *
 * Returns 1 if successfull, 0 otherwise
 * ---------------------------------------------------------------------- */
int ply_close(p_ply ply);

#ifdef __cplusplus
}
#endif

#endif /* RPLY_H */

/* ----------------------------------------------------------------------
 * Copyright (C) 2003-2011 Diego Nehab. All rights reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
 * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 * ---------------------------------------------------------------------- */