cbgpx.h File Reference

Set of functions for creating GPX files. More...

#include "cbthr.h"
#include <stdio.h>
#include <wchar.h>

Go to the source code of this file.

Data Structures
struct	t_cbgpx
Functions
short	cbgpx_isvalid (const t_cbgpx *aHandle)
	Checks, if the given handle of the GPX file is valied.
short	cbgpx_opena (t_cbgpx *theHandle, const char *aFileName)
	Opens the given file as a GPX file, ANSI file name.
short	cbgpx_openw (t_cbgpx *theHandle, const wchar_t *aFileName)
	Opens the given file as a GPX file, wide char file name.
void	cbgpx_close (t_cbgpx *aHandle)
	Closes the GPX file.
short	cbgpx_write (t_cbgpx *aHandle, double aLat, double aLon, double anAlt)
	Writes the given coordinates into the GPX file.

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Detailed Description

Set of functions for creating GPX files.

See also GPX: The GPS exchange format , http://www.topografix.com/gpx.asp.

Example: the following code:

 #include "cbgpx.h"

 int main() {
   t_cbgpx  hgpx;

   if (cbgpx_opena(&hgpx, "test.gpx") != 0) {
     cbgpx_write(&hgpx, 49.2, 11.7, 403.6);
     ...
     cbgpx_write(&hgpx, 49.5, 12.2, 398.3);
     cbgpx_close(&hgpx);
   }
 }

produces the following GPX file in "test.gpx":

 <?xml version="1.0"?>
 <gpx xmlns="http://www.topografix.com/GPX/1/0">
   <time>2008-11-23T16:40:07Z</time>
   <wpt lat="49.2" lon="11.7">
     <ele>403.6</ele>
     <time>2008-11-23T16:46:09Z</time>
     <name>0</name>
     <desc>0</desc>
     <sym>Dot</sym>
     <type>Dot</type>
   </wpt>
   <!-- ... -->
   <wpt lat="49.5" lon="12.2">
     <ele>398.3</ele>
     <time>2008-11-23T17:05:51Z</time>
     <name>275</name>
     <desc>275</desc>
     <sym>Dot</sym>
     <type>Dot</type>
   </wpt>
   <bounds minlat="49.2" minlon="11.7" maxlat="49.5" maxlon="12.2" />
 </gpx>

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Function Documentation

void cbgpx_close

(

t_cbgpx *

aHandle

)

Closes the GPX file.

The function writes the following closing information into the GPX file

and closes the file handle. Afterwards it resets the handle of the GPX file.

Parameters:

aHandle

the handle of the GPX file to close.

short cbgpx_isvalid

(

const t_cbgpx *

aHandle

)

Checks, if the given handle of the GPX file is valied.

Parameters:

aHandle

pointer to the handle to check

Returns:

!= 0 if the handle is valid, 0 else.

short cbgpx_opena	(	t_cbgpx *	theHandle,
		const char *	aFileName
	)

Opens the given file as a GPX file, ANSI file name.

The function opens the given file and writes the following initial information into it:

 <?xml version="1.0"?>
 <gpx xmlns="http://www.topografix.com/GPX/1/0">
   <time>[current time]</time>

where [current time] is the current system time in format yyyy-MM-ddTHH:mm:ssZ

Parameters:

	theHandle	the resulting handle of the GPX file.
	aFileName	the name of the file to open.

Returns:

!= 0 if everything went OK, 0 on error.

short cbgpx_openw	(	t_cbgpx *	theHandle,
		const wchar_t *	aFileName
	)

Opens the given file as a GPX file, wide char file name.

Converts the given file name into multibyte and uses cbgpx_opena() in order to open the GPX file.

Parameters:

	theHandle	the resulting handle of the GPX file.
	aFileName	the name of the file to open.

Returns:

!= 0 if everything went OK, 0 on error.

short cbgpx_write	(	t_cbgpx *	aHandle,
		double	aLat,
		double	aLon,
		double	anAlt
	)

Writes the given coordinates into the GPX file.

The function writes the following information into the GPX file:

   <wpt lat="[latitude]" lon="[longitude]">
     <ele>[altitude]</ele>
     <time>[current time]</time>
     <name>0</name>
     <desc>0</desc>
     <sym>Dot</sym>
     <type>Dot</type>
   </wpt>

where:

1. [latitude] is the given latitude aLat with a dot as decimal point
2. [longitude] is the given longitude aLon with a dot as decimal point
3. [altitude] is the given altitude anAlt with a dot as decimal point
4. long is the given latitude with dot as the decimal point separator
5. [current time] is the current system time in format yyyy-MM-ddTHH:mm:ssZ

Parameters:

	aHandle	the GPX file handle.
	aLat	the latitude, positive for North, negative for South, decimal degrees.
	aLon	the longitude, positive for East, negative for West, decimal degrees.
	anAlt	the altitude in meters.

Returns:

!= 0 if everything went OK, 0 on error.

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