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qgsspatialiteprovider.cpp
4541 lines (4226 loc) · 154 KB
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qgsspatialiteprovider.cpp
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/***************************************************************************
qgsspatialiteprovider.cpp Data provider for SpatiaLite DBMS
begin : Dec, 2008
copyright : (C) 2008 Sandro Furieri
email : a.furieri@lqt.it
***************************************************************************/
/***************************************************************************
* *
* This program is free software; you can redistribute it and/or modify *
* it under the terms of the GNU General Public License as published by *
* the Free Software Foundation; either version 2 of the License, or *
* (at your option) any later version. *
* *
***************************************************************************/
#include <qgis.h>
#include <qgsapplication.h>
#include <qgsfeature.h>
#include <qgsfield.h>
#include <qgsgeometry.h>
#include <qgsmessageoutput.h>
#include <qgsrectangle.h>
#include <qgscoordinatereferencesystem.h>
#include "qgsspatialiteprovider.h"
#include "qgslogger.h"
#ifdef _MSC_VER
#define strcasecmp(a,b) stricmp(a,b)
#endif
const QString SPATIALITE_KEY = "spatialite";
const QString SPATIALITE_DESCRIPTION = "SpatiaLite data provider";
QMap < QString, QgsSpatiaLiteProvider::SqliteHandles * >QgsSpatiaLiteProvider::SqliteHandles::handles;
QgsSpatiaLiteProvider::QgsSpatiaLiteProvider( QString const &uri )
: QgsVectorDataProvider( uri )
, geomType( QGis::WKBUnknown )
, sqliteHandle( NULL )
, sqliteStatement( NULL )
, mSrid( -1 )
, spatialIndexRTree( false )
, spatialIndexMbrCache( false )
{
nDims = GAIA_XY;
QgsDataSourceURI anUri = QgsDataSourceURI( uri );
// parsing members from the uri structure
mTableName = anUri.table();
mGeometryColumn = anUri.geometryColumn();
mSqlitePath = anUri.database();
mSubsetString = anUri.sql();
mPrimaryKey = anUri.keyColumn();
mQuery = mTableName;
// trying to open the SQLite DB
spatialite_init( 0 );
valid = true;
handle = SqliteHandles::openDb( mSqlitePath );
if ( handle == NULL )
{
valid = false;
return;
}
sqliteHandle = handle->handle();
if ( !checkLayerType() ) // check if this one Layer is based on a Table, View or VirtualShapefile
{
// invalid metadata
numberFeatures = 0;
valid = false;
QgsDebugMsg( "Invalid SpatiaLite layer" );
closeDb();
return;
}
enabledCapabilities = QgsVectorDataProvider::SelectAtId | QgsVectorDataProvider::SelectGeometryAtId;
if ( mTableBased && !mReadOnly )
{
// enabling editing only for Tables [excluding Views and VirtualShapes]
enabledCapabilities |= QgsVectorDataProvider::DeleteFeatures;
enabledCapabilities |= QgsVectorDataProvider::ChangeGeometries;
enabledCapabilities |= QgsVectorDataProvider::ChangeAttributeValues;
enabledCapabilities |= QgsVectorDataProvider::AddFeatures;
enabledCapabilities |= QgsVectorDataProvider::AddAttributes;
}
if ( !getGeometryDetails() ) // gets srid and geometry type
{
// the table is not a geometry table
numberFeatures = 0;
valid = false;
QgsDebugMsg( "Invalid SpatiaLite layer" );
closeDb();
return;
}
if ( !getTableSummary() ) // gets the extent and feature count
{
numberFeatures = 0;
valid = false;
QgsDebugMsg( "Invalid SpatiaLite layer" );
closeDb();
return;
}
// load the columns list
loadFields();
if ( sqliteHandle == NULL )
{
valid = false;
QgsDebugMsg( "Invalid SpatiaLite layer" );
return;
}
//fill type names into sets
mNativeTypes
<< QgsVectorDataProvider::NativeType( tr( "Binary object (BLOB)" ), "SQLITE_BLOB", QVariant::ByteArray )
<< QgsVectorDataProvider::NativeType( tr( "Text" ), "SQLITE_TEXT", QVariant::String )
<< QgsVectorDataProvider::NativeType( tr( "Decimal number (double)" ), "SQLITE_FLOAT", QVariant::Double, 0, 20, 0, 20 )
<< QgsVectorDataProvider::NativeType( tr( "Whole number (integer)" ), "SQLITE_INTEGER", QVariant::LongLong, 0, 20 )
;
}
QgsSpatiaLiteProvider::~QgsSpatiaLiteProvider()
{
closeDb();
}
void QgsSpatiaLiteProvider::loadFields()
{
int ret;
int i;
sqlite3_stmt *stmt = NULL;
char **results;
int rows;
int columns;
char *errMsg = NULL;
QString pkName;
int pkCount = 0;
int fldNo = 0;
QString sql;
attributeFields.clear();
if ( !isQuery )
{
mPrimaryKey.clear();
sql = QString( "PRAGMA table_info(%1)" ).arg( quotedIdentifier( mTableName ) );
ret = sqlite3_get_table( sqliteHandle, sql.toUtf8().constData(), &results, &rows, &columns, &errMsg );
if ( ret != SQLITE_OK )
goto error;
if ( rows < 1 )
;
else
{
for ( i = 1; i <= rows; i++ )
{
QString name = QString::fromUtf8( results[( i * columns ) + 1] );
const char *type = results[( i * columns ) + 2];
QString pk = results[( i * columns ) + 5];
if ( pk.toInt() != 0 )
{
// found a Primary Key column
pkCount++;
pkName = name;
}
if ( name != mGeometryColumn )
{
// for sure any SQLite value can be represented as SQLITE_TEXT
QVariant::Type fieldType = QVariant::String;
// making some assumptions in order to guess a more realistic type
if ( strcasecmp( type, "int" ) == 0 ||
strcasecmp( type, "integer" ) == 0 ||
strcasecmp( type, "bigint" ) == 0 ||
strcasecmp( type, "smallint" ) == 0 ||
strcasecmp( type, "tinyint" ) == 0 ||
strcasecmp( type, "boolean" ) == 0 )
{
fieldType = QVariant::Int;
}
else if ( strcasecmp( type, "real" ) == 0 ||
strcasecmp( type, "double" ) == 0 ||
strcasecmp( type, "double precision" ) == 0 ||
strcasecmp( type, "float" ) == 0 )
{
fieldType = QVariant::Double;
}
attributeFields.insert( fldNo++, QgsField( name, fieldType, type, 0, 0, "" ) );
}
}
}
sqlite3_free_table( results );
}
else
{
sql = QString( "select * from %1 limit 1" ).arg( mQuery );
if ( sqlite3_prepare_v2( sqliteHandle, sql.toUtf8().constData(), -1, &stmt, NULL ) != SQLITE_OK )
{
// some error occurred
QgsDebugMsg( QString( "SQLite error: %1\n\nSQL: %2" )
.arg( sql )
.arg( QString::fromUtf8( sqlite3_errmsg( sqliteHandle ) ) ) );
return;
}
ret = sqlite3_step( stmt );
if ( ret == SQLITE_DONE )
{
// there are no rows to fetch
sqlite3_finalize( stmt );
return;
}
if ( ret == SQLITE_ROW )
{
// one valid row has been fetched from the result set
columns = sqlite3_column_count( stmt );
for ( i = 0; i < columns; i++ )
{
QString name = QString::fromUtf8( sqlite3_column_name( stmt, i ) );
const char *type = sqlite3_column_decltype( stmt, i );
if ( type == NULL )
type = "TEXT";
if ( name == mPrimaryKey )
{
pkCount++;
pkName = name;
}
if ( name != mGeometryColumn )
{
// for sure any SQLite value can be represented as SQLITE_TEXT
QVariant::Type fieldType = QVariant::String;
// making some assumptions in order to guess a more realistic type
if ( strcasecmp( type, "int" ) == 0 ||
strcasecmp( type, "integer" ) == 0 ||
strcasecmp( type, "bigint" ) == 0 ||
strcasecmp( type, "smallint" ) == 0 ||
strcasecmp( type, "tinyint" ) == 0 ||
strcasecmp( type, "boolean" ) == 0 )
{
fieldType = QVariant::Int;
}
else if ( strcasecmp( type, "real" ) == 0 ||
strcasecmp( type, "double" ) == 0 ||
strcasecmp( type, "double precision" ) == 0 ||
strcasecmp( type, "float" ) == 0 )
{
fieldType = QVariant::Double;
}
attributeFields.insert( fldNo++, QgsField( name, fieldType, type, 0, 0, "" ) );
}
}
}
sqlite3_finalize( stmt );
}
if ( pkCount == 1 )
{
// setting the Primary Key column name
mPrimaryKey = pkName;
}
return;
error:
// unexpected error
if ( errMsg != NULL )
{
QgsDebugMsg( QString( "SQL error: %1" ).arg( QString::fromUtf8( errMsg ) ) );
sqlite3_free( errMsg );
}
}
QString QgsSpatiaLiteProvider::storageType() const
{
return "SQLite database with SpatiaLite extension";
}
bool QgsSpatiaLiteProvider::featureAtId( int featureId, QgsFeature & feature, bool fetchGeometry, QgsAttributeList fetchAttributes )
{
sqlite3_stmt *stmt = NULL;
feature.setValid( false );
QString primaryKey = !isQuery ? "ROWID" : quotedIdentifier( mPrimaryKey );
QString sql = QString( "SELECT %1" ).arg( primaryKey );
for ( QgsAttributeList::const_iterator it = fetchAttributes.constBegin(); it != fetchAttributes.constEnd(); ++it )
{
const QgsField & fld = field( *it );
const QString & fieldname = fld.name();
sql += "," + quotedIdentifier( fieldname );
}
if ( fetchGeometry )
{
sql += QString( ", AsBinary(%1)" ).arg( quotedIdentifier( mGeometryColumn ) );
}
sql += QString( " FROM %1 WHERE %2 = %3" )
.arg( mQuery )
.arg( primaryKey )
.arg( featureId );
if ( sqlite3_prepare_v2( sqliteHandle, sql.toUtf8().constData(), -1, &stmt, NULL ) != SQLITE_OK )
{
// some error occurred
QgsDebugMsg( QString( "SQLite error: %1\n\nSQL: %2" )
.arg( sql )
.arg( QString::fromUtf8( sqlite3_errmsg( sqliteHandle ) ) ) );
return false;
}
int ret = sqlite3_step( stmt );
if ( ret == SQLITE_DONE )
{
// there are no more rows to fetch - we can stop looping destroying the SQLite statement
sqlite3_finalize( stmt );
return false;
}
if ( ret == SQLITE_ROW )
{
// one valid row has been fetched from the result set
if ( !mFetchGeom )
{
// no geometry was required
feature.setGeometryAndOwnership( 0, 0 );
}
feature.clearAttributeMap();
int ic;
int n_columns = sqlite3_column_count( stmt );
for ( ic = 0; ic < n_columns; ic++ )
{
if ( ic == 0 )
{
// first column always contains the ROWID (or the primary key)
feature.setFeatureId( sqlite3_column_int( stmt, ic ) );
}
else
{
// iterate attributes
bool fetched = false;
int nAttr = 1;
for ( QgsAttributeList::const_iterator it = fetchAttributes.constBegin(); it != fetchAttributes.constEnd(); it++ )
{
if ( nAttr == ic )
{
// ok, this one is the corresponding attribure
if ( sqlite3_column_type( stmt, ic ) == SQLITE_INTEGER )
{
// INTEGER value
feature.addAttribute( *it, sqlite3_column_int( stmt, ic ) );
fetched = true;
}
else if ( sqlite3_column_type( stmt, ic ) == SQLITE_FLOAT )
{
// DOUBLE value
feature.addAttribute( *it, sqlite3_column_double( stmt, ic ) );
fetched = true;
}
else if ( sqlite3_column_type( stmt, ic ) == SQLITE_TEXT )
{
// TEXT value
const char *txt = ( const char * ) sqlite3_column_text( stmt, ic );
QString str = QString::fromUtf8( txt );
feature.addAttribute( *it, str );
fetched = true;
}
else
{
// assuming NULL
feature.addAttribute( *it, QVariant( QString::null ) );
fetched = true;
}
}
nAttr++;
}
if ( fetched )
{
continue;
}
if ( mFetchGeom )
{
QString geoCol = QString( "AsBinary(%1)" ).arg( quotedIdentifier( mGeometryColumn ) );
if ( strcasecmp( geoCol.toUtf8().constData(), sqlite3_column_name( stmt, ic ) ) == 0 )
{
if ( sqlite3_column_type( stmt, ic ) == SQLITE_BLOB )
{
unsigned char *featureGeom = NULL;
size_t geom_size = 0;
const void *blob = sqlite3_column_blob( stmt, ic );
size_t blob_size = sqlite3_column_bytes( stmt, ic );
convertToGeosWKB ( (const unsigned char *)blob, blob_size,
&featureGeom, &geom_size );
if ( featureGeom )
feature.setGeometryAndOwnership( featureGeom, geom_size );
else
feature.setGeometryAndOwnership( 0, 0 );
}
else
{
// NULL geometry
feature.setGeometryAndOwnership( 0, 0 );
}
}
}
}
}
}
else
{
// some unexpected error occurred
QgsDebugMsg( QString( "sqlite3_step() error: %1" ).arg( QString::fromUtf8( sqlite3_errmsg( sqliteHandle ) ) ) );
sqlite3_finalize( stmt );
return false;
}
sqlite3_finalize( stmt );
feature.setValid( true );
return true;
}
bool QgsSpatiaLiteProvider::nextFeature( QgsFeature & feature )
{
feature.setValid( false );
if ( !valid )
{
QgsDebugMsg( "Read attempt on an invalid SpatiaLite data source" );
return false;
}
if ( sqliteStatement == NULL )
{
QgsDebugMsg( "Invalid current SQLite statement" );
return false;
}
int ret = sqlite3_step( sqliteStatement );
if ( ret == SQLITE_DONE )
{
// there are no more rows to fetch - we can stop looping destroying the SQLite statement
sqlite3_finalize( sqliteStatement );
sqliteStatement = NULL;
return false;
}
if ( ret == SQLITE_ROW )
{
// one valid row has been fetched from the result set
if ( !mFetchGeom )
{
// no geometry was required
feature.setGeometryAndOwnership( 0, 0 );
}
feature.clearAttributeMap();
int ic;
int n_columns = sqlite3_column_count( sqliteStatement );
for ( ic = 0; ic < n_columns; ic++ )
{
if ( ic == 0 )
{
// first column always contains the ROWID (or the primary key)
feature.setFeatureId( sqlite3_column_int( sqliteStatement, ic ) );
}
else
{
// iterate attributes
bool fetched = false;
int nAttr = 1;
for ( QgsAttributeList::const_iterator it = mAttributesToFetch.constBegin(); it != mAttributesToFetch.constEnd(); it++ )
{
if ( nAttr == ic )
{
// ok, this one is the corresponding attribure
if ( sqlite3_column_type( sqliteStatement, ic ) == SQLITE_INTEGER )
{
// INTEGER value
feature.addAttribute( *it, sqlite3_column_int( sqliteStatement, ic ) );
fetched = true;
}
else if ( sqlite3_column_type( sqliteStatement, ic ) == SQLITE_FLOAT )
{
// DOUBLE value
feature.addAttribute( *it, sqlite3_column_double( sqliteStatement, ic ) );
fetched = true;
}
else if ( sqlite3_column_type( sqliteStatement, ic ) == SQLITE_TEXT )
{
// TEXT value
const char *txt = ( const char * ) sqlite3_column_text( sqliteStatement, ic );
QString str = QString::fromUtf8( txt );
feature.addAttribute( *it, str );
fetched = true;
}
else
{
// assuming NULL
feature.addAttribute( *it, QVariant( QString::null ) );
fetched = true;
}
}
nAttr++;
}
if ( fetched )
{
continue;
}
if ( mFetchGeom )
{
QString geoCol = QString( "AsBinary(%1)" ).arg( quotedIdentifier( mGeometryColumn ) );
if ( strcasecmp( geoCol.toUtf8().constData(), sqlite3_column_name( sqliteStatement, ic ) ) == 0 )
{
if ( sqlite3_column_type( sqliteStatement, ic ) == SQLITE_BLOB )
{
unsigned char *featureGeom = NULL;
size_t geom_size = 0;
const void *blob = sqlite3_column_blob( sqliteStatement, ic );
size_t blob_size = sqlite3_column_bytes( sqliteStatement, ic );
convertToGeosWKB ( (const unsigned char *)blob, blob_size,
&featureGeom, &geom_size );
if ( featureGeom )
feature.setGeometryAndOwnership( featureGeom, geom_size );
else
feature.setGeometryAndOwnership( 0, 0 );
}
else
{
// NULL geometry
feature.setGeometryAndOwnership( 0, 0 );
}
}
}
}
}
}
else
{
// some unexpected error occurred
QgsDebugMsg( QString( "sqlite3_step() error: %1" ).arg( QString::fromUtf8( sqlite3_errmsg( sqliteHandle ) ) ) );
sqlite3_finalize( sqliteStatement );
sqliteStatement = NULL;
return false;
}
feature.setValid( true );
return true;
}
int QgsSpatiaLiteProvider::computeSizeFromGeosWKB2D( const unsigned char *blob,
size_t size, int type, int nDims,
int little_endian, int endian_arch )
{
// calculating the size required to store this WKB
int rings;
int points;
int ib;
const unsigned char *p_in = blob;
int gsize = 5;
p_in = blob + 5;
switch ( type )
{
// compunting the required size
case GAIA_POINT:
switch ( nDims )
{
case GAIA_XY_Z_M:
gsize += 4 * sizeof(double);
break;
case GAIA_XY_M:
case GAIA_XY_Z:
gsize += 3 * sizeof(double);
break;
default:
gsize += 2 * sizeof(double);
break;
}
break;
case GAIA_LINESTRING:
points = gaiaImport32 ( p_in, little_endian, endian_arch );
gsize += 4;
switch ( nDims )
{
case GAIA_XY_Z_M:
gsize += points * ( 4 * sizeof(double) );
break;
case GAIA_XY_M:
case GAIA_XY_Z:
gsize += points * ( 3 * sizeof(double) );
break;
default:
gsize += points * ( 2 * sizeof(double) );
break;
}
break;
case GAIA_POLYGON:
rings = gaiaImport32 ( p_in, little_endian, endian_arch );
p_in += 4;
gsize += 4;
for ( ib = 0; ib < rings; ib++ )
{
points = gaiaImport32 ( p_in, little_endian, endian_arch );
p_in += 4;
gsize += 4;
switch ( nDims )
{
case GAIA_XY_Z_M:
gsize += points * ( 4 * sizeof(double) );
break;
case GAIA_XY_M:
case GAIA_XY_Z:
gsize += points * ( 3 * sizeof(double) );
break;
default:
gsize += points * ( 2 * sizeof(double) );
break;
}
p_in += points * ( 2 * sizeof(double) );
}
break;
default:
gsize += computeSizeFromMultiWKB2D( p_in, nDims, little_endian,
endian_arch );
break;
}
return gsize;
}
int QgsSpatiaLiteProvider::computeSizeFromMultiWKB2D( const unsigned char *p_in,
int nDims,
int little_endian,
int endian_arch )
{
// calculating the size required to store this WKB
int entities;
int type;
int rings;
int points;
int ie;
int ib;
int size = 0;
entities = gaiaImport32 ( p_in, little_endian, endian_arch );
p_in += 4;
size += 4;
for ( ie = 0; ie < entities; ie++ )
{
type = gaiaImport32 ( p_in + 1, little_endian, endian_arch );
p_in += 5;
size += 5;
switch ( type )
{
// compunting the required size
case GAIA_POINT:
switch ( nDims )
{
case GAIA_XY_Z_M:
size += 4 * sizeof(double);
break;
case GAIA_XY_Z:
case GAIA_XY_M:
size += 3 * sizeof(double);
break;
default:
size += 2 * sizeof(double);
break;
}
p_in += 2 * sizeof(double);
break;
case GAIA_LINESTRING:
points = gaiaImport32 ( p_in, little_endian, endian_arch );
p_in += 4;
size += 4;
switch ( nDims )
{
case GAIA_XY_Z_M:
size += points * ( 4 * sizeof(double) );
break;
case GAIA_XY_Z:
case GAIA_XY_M:
size += points * ( 3 * sizeof(double) );
break;
default:
size += points * ( 2 * sizeof(double) );
break;
}
p_in += points * ( 2 * sizeof(double) );
break;
case GAIA_POLYGON:
rings = gaiaImport32 ( p_in, little_endian, endian_arch );
p_in += 4;
size += 4;
for ( ib = 0; ib < rings; ib++ )
{
points = gaiaImport32 ( p_in, little_endian, endian_arch );
p_in += 4;
size += 4;
switch ( nDims )
{
case GAIA_XY_Z_M:
size += points * ( 4 * sizeof(double) );
break;
case GAIA_XY_Z:
case GAIA_XY_M:
size += points * ( 3 * sizeof(double) );
break;
default:
size += points * ( 2 * sizeof(double) );
break;
}
p_in += points * ( 2 * sizeof(double) );
}
break;
}
}
return size;
}
int QgsSpatiaLiteProvider::computeSizeFromGeosWKB3D( const unsigned char *blob,
size_t size, int type, int nDims,
int little_endian, int endian_arch )
{
// calculating the size required to store this WKB
int rings;
int points;
int ib;
const unsigned char *p_in = blob;
int gsize = 5;
p_in = blob + 5;
switch ( type )
{
// compunting the required size
case GEOS_3D_POINT:
switch ( nDims )
{
case GAIA_XY_Z_M:
gsize += 4 * sizeof(double);
break;
case GAIA_XY_M:
case GAIA_XY_Z:
gsize += 3 * sizeof(double);
break;
default:
gsize += 2 * sizeof(double);
break;
}
break;
case GEOS_3D_LINESTRING:
points = gaiaImport32 ( p_in, little_endian, endian_arch );
gsize += 4;
switch ( nDims )
{
case GAIA_XY_Z_M:
gsize += points * ( 4 * sizeof(double) );
break;
case GAIA_XY_M:
case GAIA_XY_Z:
gsize += points * ( 3 * sizeof(double) );
break;
default:
gsize += points * ( 2 * sizeof(double) );
break;
}
break;
case GEOS_3D_POLYGON:
rings = gaiaImport32 ( p_in, little_endian, endian_arch );
p_in += 4;
gsize += 4;
for ( ib = 0; ib < rings; ib++ )
{
points = gaiaImport32 ( p_in, little_endian, endian_arch );
p_in += 4;
gsize += 4;
switch ( nDims )
{
case GAIA_XY_Z_M:
gsize += points * ( 4 * sizeof(double) );
break;
case GAIA_XY_M:
case GAIA_XY_Z:
gsize += points * ( 3 * sizeof(double) );
break;
default:
gsize += points * ( 2 * sizeof(double) );
break;
}
p_in += points * ( 3 * sizeof(double) );
}
break;
default:
gsize += computeSizeFromMultiWKB3D( p_in, nDims, little_endian,
endian_arch );
break;
}
return gsize;
}
int QgsSpatiaLiteProvider::computeSizeFromMultiWKB3D( const unsigned char *p_in,
int nDims,
int little_endian,
int endian_arch )
{
// calculating the size required to store this WKB
int entities;
int type;
int rings;
int points;
int ie;
int ib;
int size = 0;
entities = gaiaImport32 ( p_in, little_endian, endian_arch );
p_in += 4;
size += 4;
for ( ie = 0; ie < entities; ie++ )
{
type = gaiaImport32 ( p_in + 1, little_endian, endian_arch );
p_in += 5;
size += 5;
switch ( type )
{
// compunting the required size
case GEOS_3D_POINT:
switch ( nDims )
{
case GAIA_XY_Z_M:
size += 4 * sizeof(double);
break;
case GAIA_XY_Z:
case GAIA_XY_M:
size += 3 * sizeof(double);
break;
default:
size += 2 * sizeof(double);
break;
}
p_in += 3 * sizeof(double);
break;
case GEOS_3D_LINESTRING:
points = gaiaImport32 ( p_in, little_endian, endian_arch );
p_in += 4;
size += 4;
switch ( nDims )
{
case GAIA_XY_Z_M:
size += points * ( 4 * sizeof(double) );
break;
case GAIA_XY_Z:
case GAIA_XY_M:
size += points * ( 3 * sizeof(double) );
break;
default:
size += points * ( 2 * sizeof(double) );
break;
}
p_in += points * ( 3 * sizeof(double) );
break;
case GEOS_3D_POLYGON:
rings = gaiaImport32 ( p_in, little_endian, endian_arch );
p_in += 4;
size += 4;
for ( ib = 0; ib < rings; ib++ )
{
points = gaiaImport32 ( p_in, little_endian, endian_arch );
p_in += 4;
size += 4;
switch ( nDims )
{
case GAIA_XY_Z_M:
size += points * ( 4 * sizeof(double) );
break;
case GAIA_XY_Z:
case GAIA_XY_M:
size += points * ( 3 * sizeof(double) );
break;
default:
size += points * ( 2 * sizeof(double) );
break;
}
p_in += points * ( 3 * sizeof(double) );
}
break;
}
}
return size;
}
void QgsSpatiaLiteProvider::convertFromGeosWKB ( const unsigned char *blob,
size_t blob_size,
unsigned char **wkb,
size_t *geom_size,
int nDims )
{
// attempting to convert from 2D/3D GEOS own WKB
int type;
int gDims;
int gsize;
int little_endian;
int endian_arch = gaiaEndianArch ();
*wkb = NULL;
*geom_size = 0;
if ( blob_size < 5 )
return;
if ( *( blob + 0 ) == 0x01 )
little_endian = GAIA_LITTLE_ENDIAN;
else
little_endian = GAIA_BIG_ENDIAN;
type = gaiaImport32 ( blob + 1, little_endian, endian_arch );
if (type == GEOS_3D_POINT || type == GEOS_3D_LINESTRING
|| type == GEOS_3D_POLYGON
|| type == GEOS_3D_MULTIPOINT || type == GEOS_3D_MULTILINESTRING
|| type == GEOS_3D_MULTIPOLYGON || type == GEOS_3D_GEOMETRYCOLLECTION)
gDims = 3;
else if (type == GAIA_POINT || type == GAIA_LINESTRING
|| type == GAIA_POLYGON || type == GAIA_MULTIPOINT
|| type == GAIA_MULTILINESTRING || type == GAIA_MULTIPOLYGON
|| type == GAIA_GEOMETRYCOLLECTION)
gDims = 2;
else
return;
if ( gDims == 2 && nDims == GAIA_XY )
{
// already 2D: simply copying is required
unsigned char *wkbGeom = new unsigned char[blob_size + 1];
memset( wkbGeom, '\0', blob_size + 1 );
memcpy( wkbGeom, blob, blob_size );
*wkb = wkbGeom;
*geom_size = blob_size + 1;
return;
}
// we need creating a GAIA WKB
if ( gDims == 3 )
gsize = computeSizeFromGeosWKB3D( blob, blob_size, type, nDims,
little_endian, endian_arch );
else
gsize = computeSizeFromGeosWKB2D( blob, blob_size, type, nDims,
little_endian, endian_arch );
unsigned char *wkbGeom = new unsigned char[gsize];
memset( wkbGeom, '\0', gsize );
if ( gDims == 3 )
convertFromGeosWKB3D( blob, blob_size, wkbGeom, gsize, nDims,
little_endian, endian_arch );
else
convertFromGeosWKB2D( blob, blob_size, wkbGeom, gsize, nDims,
little_endian, endian_arch );
*wkb = wkbGeom;
*geom_size = gsize;
}
void QgsSpatiaLiteProvider::convertFromGeosWKB2D ( const unsigned char *blob,
size_t blob_size,
unsigned char *wkb,
size_t geom_size,
int nDims,
int little_endian,
int endian_arch )
{
// attempting to convert from 2D GEOS own WKB
int type;
int entities;
int rings;
int points;
int ie;
int ib;
int iv;
const unsigned char *p_in;
unsigned char *p_out = wkb;
double coord;
// building from GEOS 2D WKB
*p_out++ = 0x01; // little endian byte order