gsds.c File Reference

OGSF library - dataset loading and management (lower level functions) More...

#include <stdlib.h>
#include <string.h>
#include <grass/gis.h>
#include <grass/glocale.h>
#include <grass/ogsf.h>

Include dependency graph for gsds.c:

Go to the source code of this file.

Macros
#define	LUCKY   33
#define	BLOC   20
#define	MAX_DS   100

Functions
int	gsds_findh (const char *name, unsigned int *changes, unsigned int *types, int begin)
	Get handle to gsds. More...
int	gsds_newh (const char *name)
	Get handle to gsds. More...
typbuff *	gsds_get_typbuff (int id, unsigned int change_flag)
	Get data buffer. More...
char *	gsds_get_name (int id)
	Get name. More...
int	gsds_free_datah (int id)
	Free allocated dataset. More...
int	gsds_free_data_buff (int id, int typ)
	Free allocated buffer. More...
size_t	free_data_buffs (dataset *ds, int typ)
	Free data buffer. More...
size_t	gsds_alloc_typbuff (int id, int *dims, int ndims, int type)
	Allocates correct buffer according to type, keeps track of total mem. More...
int	gsds_get_changed (int id)
	ADD. More...
int	gsds_set_changed (int id, unsigned int reason)
	ADD. More...
int	gsds_get_type (int id)
	ADD. More...

Detailed Description

OGSF library - dataset loading and management (lower level functions)

GRASS OpenGL gsurf OGSF Library

The idea here is to treat datasets as separate objects, which SHOULD:

• allow easier reuse of data for different attributes.
• allow a mechanism for changing data and have changes reflected in each attribute using that data.
• allow a mechanism to automatically update data when the data source is changed.
• allow easier weaning from GRASS.
• allow easier use of shared memory between processes.

These structures are defined in gstypes.h:

typedef struct{ float *fb; int *ib; short *sb; char *cb; struct BM *bm; } typbuff;

How about adding a transform func here, so GET_MAPATT would do an on-the-fly transformation? Or even a transform func LIST!

typedef struct{ int data_id; int dims[MAXDIMS]; int ndims; int numbytes; char unique_name[80]; typbuff databuff; int changed; int need_reload; } dataset;

(C) 1999-2008 by the GRASS Development Team

This program is free software under the GNU General Public License (>=v2). Read the file COPYING that comes with GRASS for details.

Author

Bill Brown UI GMS Lab

Doxygenized by Martin Landa <landa.martin gmail.com> (May 2008)

Definition in file gsds.c.

Macro Definition Documentation

BLOC

#define BLOC   20

Definition at line 64 of file gsds.c.

LUCKY

#define LUCKY   33

Definition at line 63 of file gsds.c.

MAX_DS

#define MAX_DS   100

Definition at line 65 of file gsds.c.

Function Documentation

free_data_buffs()

size_t free_data_buffs	(	dataset *	ds,
		int	typ
	)

Free data buffer.

Parameters

ds	pointer to dataset struct
typ	data type

Returns

freed size

Definition at line 393 of file gsds.c.

gsds_alloc_typbuff()

size_t gsds_alloc_typbuff	(	int	id,
		int *	dims,
		int	ndims,
		int	type
	)

Allocates correct buffer according to type, keeps track of total mem.

Todo:

add ATTY_CONST

Parameters

id	dataset id
dims	array of dimensions
ndims	number of dimensions
type	data type

Returns

amount of allocated memory

Definition at line 480 of file gsds.c.

gsds_findh()

int gsds_findh	(	const char *	name,
		unsigned int *	changes,
		unsigned int *	types,
		int	begin
	)

Get handle to gsds.

Successive calls will continue search until "begin" is set (problem here is, unique_name no longer uniquely identifies dataset, since changes may be made; but unique_name should still be useful for reloading dataset) changes & types are set to actual for dataset if found.

Parameters

name
changes,types	acceptable changes & types, flags may be or'd not changed is assumed to always be acceptable
begin	flag to indicate search from beginning

Returns

data id

-1 not found

Definition at line 188 of file gsds.c.

gsds_free_data_buff()

int gsds_free_data_buff	(	int	id,
		int	typ
	)

Free allocated buffer.

Parameters

id	dataset id
typ	data type

Returns

0 not found

1 found

Definition at line 369 of file gsds.c.

gsds_free_datah()

int gsds_free_datah

(

int

id

)

Free allocated dataset.

Parameters

id

Returns

0 not found

1 found

Definition at line 329 of file gsds.c.

References G_debug().

gsds_get_changed()

int gsds_get_changed

(

int

id

)

ADD.

Parameters

id

Returns

-1 on error

Definition at line 613 of file gsds.c.

Referenced by Gs_update_attrange().

gsds_get_name()

char* gsds_get_name

(

int

id

)

Get name.

Parameters

id

Returns

name

NULL on failure

Definition at line 303 of file gsds.c.

References GPATH_MAX.

Referenced by GS_get_cat_at_xy().

gsds_get_typbuff()

typbuff* gsds_get_typbuff	(	int	id,
		unsigned int	change_flag
	)

Get data buffer.

Doesn't prevent writing a buff thats's been gotten with change_flag == 0 (could return a copy, but willing to trust calling func for now)

Parameters

id	dataset id
change_flag	set changed flag

Returns

pointer to typbuff struct

NULL on failure

Definition at line 281 of file gsds.c.

gsds_get_type()

int gsds_get_type

(

int

id

)

ADD.

Parameters

id

Returns

Definition at line 651 of file gsds.c.

gsds_newh()

int gsds_newh

(

const char *

name

)

Get handle to gsds.

Parameters

name	raster map name

Returns

-1 on failure

data id

Definition at line 219 of file gsds.c.

gsds_set_changed()

int gsds_set_changed	(	int	id,
		unsigned int	reason
	)

ADD.

Parameters

id
reason

Returns

-1 on error

Definition at line 633 of file gsds.c.