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qgsgrassrasterprovider.cpp
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qgsgrassrasterprovider.cpp
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/***************************************************************************
qgsgrassrasterprovider.cpp - QGIS Data provider for
GRASS rasters
-------------------
begin : 16 Jan, 2010
copyright : (C) 2010 by Radim Blazek
email : radim dot blazek at gmail dot com
***************************************************************************/
/***************************************************************************
* *
* 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 <limits>
#include "qgslogger.h"
#include "qgsgrass.h"
#include "qgsrasteridentifyresult.h"
#include "qgsgrassrasterprovider.h"
#include "qgsconfig.h"
#include "qgsapplication.h"
#include "qgscoordinatetransform.h"
#include "qgsrectangle.h"
#include "qgscoordinatereferencesystem.h"
#include "qgsrasterbandstats.h"
#include <QImage>
#include <QSettings>
#include <QColor>
#include <QMessageBox>
#include <QDir>
#include <QFileInfo>
#include <QFile>
#include <QHash>
#define ERR(message) QGS_ERROR_MESSAGE(message,"GRASS provider")
#define QGS_ERROR(message) QgsError(message,"GRASS provider")
// Do not use warning dialogs, providers are also created on threads (rendering) where dialogs cannot be used (constructing QPixmap icon)
QgsGrassRasterProvider::QgsGrassRasterProvider( QString const &uri )
: QgsRasterDataProvider( uri )
, mNoDataValue( std::numeric_limits<double>::quiet_NaN() )
{
QgsDebugMsg( "QgsGrassRasterProvider: constructing with uri '" + uri + "'." );
if ( !QgsGrass::init() )
{
return;
}
// Parse URI, it is the same like using GDAL, i.e. path to raster cellhd, i.e.
// /path/to/gisdbase/location/mapset/cellhd/map
QFileInfo fileInfo( uri );
if ( !fileInfo.exists() ) // then we keep it valid forever
{
appendError( ERR( tr( "cellhd file %1 does not exist" ).arg( uri ) ) );
return;
}
mMapName = fileInfo.fileName();
QDir dir = fileInfo.dir();
QString element = dir.dirName();
if ( element != QLatin1String( "cellhd" ) )
{
appendError( ERR( tr( "Groups not yet supported" ) ) );
return;
}
dir.cdUp(); // skip cellhd
mMapset = dir.dirName();
dir.cdUp();
mLocation = dir.dirName();
dir.cdUp();
mGisdbase = dir.path();
QgsDebugMsg( QString( "gisdbase: %1" ).arg( mGisdbase ) );
QgsDebugMsg( QString( "location: %1" ).arg( mLocation ) );
QgsDebugMsg( QString( "mapset: %1" ).arg( mMapset ) );
QgsDebugMsg( QString( "mapName: %1" ).arg( mMapName ) );
mTimestamp = dataTimestamp();
mRasterValue.set( mGisdbase, mLocation, mMapset, mMapName );
//mValidNoDataValue = true;
QString error;
mCrs = QgsGrass::crs( mGisdbase, mLocation, error );
appendIfError( error );
QgsDebugMsg( "mCrs: " + mCrs.toWkt() );
// the block size can change of course when the raster is overridden
// ibut it is only called once when statistics are calculated
error.clear();
QgsGrass::size( mGisdbase, mLocation, mMapset, mMapName, &mCols, &mRows, error );
appendIfError( error );
error.clear();
mInfo = QgsGrass::info( mGisdbase, mLocation, mMapset, mMapName, QgsGrassObject::Raster,
QStringLiteral( "info" ), QgsRectangle(), 0, 0, 3000, error );
appendIfError( error );
mGrassDataType = mInfo[QStringLiteral( "TYPE" )].toInt();
QgsDebugMsg( "mGrassDataType = " + QString::number( mGrassDataType ) );
// TODO: avoid showing these strange numbers in GUI
// TODO: don't save no data values in project file, add a flag if value was defined by user
double myInternalNoDataValue;
if ( mGrassDataType == CELL_TYPE )
{
myInternalNoDataValue = INT_MIN;
}
else if ( mGrassDataType == DCELL_TYPE )
{
// Don't use numeric limits, raster layer is using
// std::fabs( myValue - mNoDataValue ) <= TINY_VALUE
// if the mNoDataValue would be a limit, the subtraction could overflow.
// No data value is shown in GUI, use some nice number.
// Choose values with small representation error.
// limit: 1.7976931348623157e+308
//myInternalNoDataValue = -1e+300;
myInternalNoDataValue = std::numeric_limits<double>::quiet_NaN();
}
else
{
if ( mGrassDataType != FCELL_TYPE )
{
QgsDebugMsg( "unexpected data type" );
}
// limit: 3.40282347e+38
//myInternalNoDataValue = -1e+30;
myInternalNoDataValue = std::numeric_limits<float>::quiet_NaN();
}
mNoDataValue = myInternalNoDataValue;
mSrcHasNoDataValue.append( true );
mSrcNoDataValue.append( mNoDataValue );
mUseSrcNoDataValue.append( true );
QgsDebugMsg( QString( "myInternalNoDataValue = %1" ).arg( myInternalNoDataValue ) );
// TODO: refresh mRows and mCols if raster was rewritten
// We have to decide some reasonable block size, not to big to occupate too much
// memory, not too small to result in too many calls to readBlock -> qgis.d.rast
// for statistics
int typeSize = dataTypeSize( dataType( 1 ) );
if ( mCols > 0 && typeSize > 0 )
{
const int cache_size = 10000000; // ~ 10 MB
mYBlockSize = cache_size / typeSize / mCols;
if ( mYBlockSize > mRows )
{
mYBlockSize = mRows;
}
QgsDebugMsg( "mYBlockSize = " + QString::number( mYBlockSize ) );
mValid = true;
}
}
QgsGrassRasterProvider::~QgsGrassRasterProvider()
{
QgsDebugMsg( "QgsGrassRasterProvider: deconstructing." );
}
QgsRasterInterface *QgsGrassRasterProvider::clone() const
{
QgsGrassRasterProvider *provider = new QgsGrassRasterProvider( dataSourceUri() );
provider->copyBaseSettings( *this );
return provider;
}
void QgsGrassRasterProvider::readBlock( int bandNo, int xBlock, int yBlock, void *block )
{
Q_UNUSED( xBlock );
clearLastError();
// TODO: optimize, see extent()
QgsDebugMsg( "yBlock = " + QString::number( yBlock ) );
QStringList arguments;
arguments.append( "map=" + mMapName + "@" + mMapset );
QgsRectangle ext = extent();
// TODO: cut the last block
double cellHeight = ext.height() / mRows;
double yMaximum = ext.yMaximum() - cellHeight * yBlock * mYBlockSize;
double yMinimum = yMaximum - cellHeight * mYBlockSize;
QgsDebugMsg( "mYBlockSize = " + QString::number( mYBlockSize ) );
arguments.append( ( QStringLiteral( "window=%1,%2,%3,%4,%5,%6" )
.arg( QgsRasterBlock::printValue( ext.xMinimum() ),
QgsRasterBlock::printValue( yMinimum ),
QgsRasterBlock::printValue( ext.xMaximum() ),
QgsRasterBlock::printValue( yMaximum ) )
.arg( mCols ).arg( mYBlockSize ) ) );
arguments.append( QStringLiteral( "format=value" ) );
QString cmd = QgsApplication::libexecPath() + "grass/modules/qgis.d.rast";
QByteArray data;
try
{
data = QgsGrass::runModule( mGisdbase, mLocation, mMapset, cmd, arguments );
}
catch ( QgsGrass::Exception &e )
{
QString error = tr( "Cannot read raster" ) + " : " + e.what();
QgsDebugMsg( error );
appendError( error );
// We don't set mValid to false, because the raster can be recreated and work next time
}
QgsDebugMsg( QString( "%1 bytes read from modules stdout" ).arg( data.size() ) );
// byteCount() in Qt >= 4.6
//int size = image->byteCount() < data.size() ? image->byteCount() : data.size();
int size = mCols * mYBlockSize * dataTypeSize( bandNo );
QgsDebugMsg( QString( "mCols = %1 mYBlockSize = %2 dataTypeSize = %3" ).arg( mCols ).arg( mYBlockSize ).arg( dataTypeSize( bandNo ) ) );
if ( size != data.size() )
{
QString error = tr( "%1 bytes expected but %2 byte were read from qgis.d.rast" ).arg( size ).arg( data.size() );
QgsDebugMsg( error );
appendError( error );
size = size < data.size() ? size : data.size();
}
memcpy( block, data.data(), size );
}
void QgsGrassRasterProvider::readBlock( int bandNo, QgsRectangle const &viewExtent, int pixelWidth, int pixelHeight, void *block, QgsRasterBlockFeedback *feedback )
{
Q_UNUSED( feedback );
QgsDebugMsg( "pixelWidth = " + QString::number( pixelWidth ) );
QgsDebugMsg( "pixelHeight = " + QString::number( pixelHeight ) );
QgsDebugMsg( "viewExtent: " + viewExtent.toString() );
clearLastError();
if ( pixelWidth <= 0 || pixelHeight <= 0 )
return;
QStringList arguments;
arguments.append( "map=" + mMapName + "@" + mMapset );
arguments.append( ( QStringLiteral( "window=%1,%2,%3,%4,%5,%6" )
.arg( QgsRasterBlock::printValue( viewExtent.xMinimum() ),
QgsRasterBlock::printValue( viewExtent.yMinimum() ),
QgsRasterBlock::printValue( viewExtent.xMaximum() ),
QgsRasterBlock::printValue( viewExtent.yMaximum() ) )
.arg( pixelWidth ).arg( pixelHeight ) ) );
arguments.append( QStringLiteral( "format=value" ) );
QString cmd = QgsApplication::libexecPath() + "grass/modules/qgis.d.rast";
QByteArray data;
try
{
data = QgsGrass::runModule( mGisdbase, mLocation, mMapset, cmd, arguments );
}
catch ( QgsGrass::Exception &e )
{
QString error = tr( "Cannot read raster" ) + " : " + e.what();
QgsDebugMsg( error );
appendError( error );
// We don't set mValid to false, because the raster can be recreated and work next time
return;
}
QgsDebugMsg( QString( "%1 bytes read from modules stdout" ).arg( data.size() ) );
// byteCount() in Qt >= 4.6
//int size = image->byteCount() < data.size() ? image->byteCount() : data.size();
int size = pixelWidth * pixelHeight * dataTypeSize( bandNo );
if ( size != data.size() )
{
QString error = tr( "%1 bytes expected but %2 byte were read from qgis.d.rast" ).arg( size ).arg( data.size() );
QgsDebugMsg( error );
appendError( error );
size = size < data.size() ? size : data.size();
}
memcpy( block, data.data(), size );
}
QgsRasterBandStats QgsGrassRasterProvider::bandStatistics( int bandNo, int stats, const QgsRectangle &boundingBox, int sampleSize, QgsRasterBlockFeedback * )
{
QgsDebugMsg( QString( "theBandNo = %1 sampleSize = %2" ).arg( bandNo ).arg( sampleSize ) );
QgsRasterBandStats myRasterBandStats;
initStatistics( myRasterBandStats, bandNo, stats, boundingBox, sampleSize );
Q_FOREACH ( const QgsRasterBandStats &stats, mStatistics )
{
if ( stats.contains( myRasterBandStats ) )
{
QgsDebugMsg( "Using cached statistics." );
return stats;
}
}
QgsRectangle extent = myRasterBandStats.extent;
int sampleRows = myRasterBandStats.height;
int sampleCols = myRasterBandStats.width;
// With stats we have to be careful about timeout, empirical value,
// 0.001 / cell should be sufficient using 0.005 to be sure + constant (ms)
int timeout = 30000 + 0.005 * xSize() * ySize();
QString error;
QHash<QString, QString> info = QgsGrass::info( mGisdbase, mLocation, mMapset, mMapName, QgsGrassObject::Raster,
QStringLiteral( "stats" ), extent, sampleRows, sampleCols, timeout, error );
if ( info.isEmpty() || !error.isEmpty() )
{
return myRasterBandStats;
}
myRasterBandStats.sum = info[QStringLiteral( "SUM" )].toDouble();
myRasterBandStats.elementCount = info[QStringLiteral( "COUNT" )].toInt();
myRasterBandStats.minimumValue = info[QStringLiteral( "MIN" )].toDouble();
myRasterBandStats.maximumValue = info[QStringLiteral( "MAX" )].toDouble();
myRasterBandStats.range = myRasterBandStats.maximumValue - myRasterBandStats.minimumValue;
myRasterBandStats.sumOfSquares = info[QStringLiteral( "SQSUM" )].toDouble();
myRasterBandStats.mean = info[QStringLiteral( "MEAN" )].toDouble();
myRasterBandStats.stdDev = info[QStringLiteral( "STDEV" )].toDouble();
QgsDebugMsg( QString( "min = %1" ).arg( myRasterBandStats.minimumValue ) );
QgsDebugMsg( QString( "max = %1" ).arg( myRasterBandStats.maximumValue ) );
QgsDebugMsg( QString( "count = %1" ).arg( myRasterBandStats.elementCount ) );
QgsDebugMsg( QString( "stdev = %1" ).arg( myRasterBandStats.stdDev ) );
myRasterBandStats.statsGathered = QgsRasterBandStats::Min | QgsRasterBandStats::Max |
QgsRasterBandStats::Range | QgsRasterBandStats::Mean |
QgsRasterBandStats::Sum | QgsRasterBandStats::SumOfSquares |
QgsRasterBandStats::StdDev;
mStatistics.append( myRasterBandStats );
return myRasterBandStats;
}
QList<QgsColorRampShader::ColorRampItem> QgsGrassRasterProvider::colorTable( int bandNo )const
{
Q_UNUSED( bandNo );
QList<QgsColorRampShader::ColorRampItem> ct;
// TODO: check if color can be really discontinuous in GRASS,
// for now we just believe that they are continuous, i.e. end and beginning
// of the ramp with the same value has the same color
// we are also expecting ordered CT records in the list
QString error;
QList<QgsGrass::Color> colors = QgsGrass::colors( mGisdbase, mLocation, mMapset, mMapName, error );
if ( !error.isEmpty() )
{
return ct;
}
QList<QgsGrass::Color>::iterator i;
double v = 0.0, r = 0.0, g = 0.0, b = 0.0;
for ( i = colors.begin(); i != colors.end(); ++i )
{
if ( ct.count() == 0 || i->value1 != v || i->red1 != r || i->green1 != g || i->blue1 != b )
{
// not added in previous rule
QgsColorRampShader::ColorRampItem ctItem1;
ctItem1.value = i->value1;
ctItem1.color = QColor::fromRgb( i->red1, i->green1, i->blue1 );
ct.append( ctItem1 );
QgsDebugMsg( QString( "color %1 %2 %3 %4" ).arg( i->value1 ).arg( i->red1 ).arg( i->green1 ).arg( i->blue1 ) );
}
QgsColorRampShader::ColorRampItem ctItem2;
ctItem2.value = i->value2;
ctItem2.color = QColor::fromRgb( i->red2, i->green2, i->blue2 );
ct.append( ctItem2 );
QgsDebugMsg( QString( "color %1 %2 %3 %4" ).arg( i->value2 ).arg( i->red2 ).arg( i->green2 ).arg( i->blue2 ) );
v = i->value2;
r = i->red2;
g = i->green2;
b = i->blue2;
}
return ct;
}
QgsCoordinateReferenceSystem QgsGrassRasterProvider::crs() const
{
return mCrs;
}
QgsRectangle QgsGrassRasterProvider::extent() const
{
// The extend can change of course so we get always fresh, to avoid running always the module
// we should save mExtent and mLastModified and check if the map was modified
QString error;
mExtent = QgsGrass::extent( mGisdbase, mLocation, mMapset, mMapName, QgsGrassObject::Raster, error );
QgsDebugMsg( "Extent got" );
return mExtent;
}
// this is only called once when statistics are calculated
int QgsGrassRasterProvider::xBlockSize() const { return mCols; }
int QgsGrassRasterProvider::yBlockSize() const
{
return mYBlockSize;
}
// TODO this should be always refreshed if raster has changed ?
// maybe also only for stats
int QgsGrassRasterProvider::xSize() const { return mCols; }
int QgsGrassRasterProvider::ySize() const { return mRows; }
QgsRasterIdentifyResult QgsGrassRasterProvider::identify( const QgsPointXY &point, QgsRaster::IdentifyFormat format, const QgsRectangle &boundingBox, int width, int height, int /*dpi*/ )
{
Q_UNUSED( boundingBox );
Q_UNUSED( width );
Q_UNUSED( height );
QMap<int, QVariant> results;
QMap<int, QVariant> noDataResults;
noDataResults.insert( 1, QVariant() );
QgsRasterIdentifyResult noDataResult( QgsRaster::IdentifyFormatValue, results );
if ( format != QgsRaster::IdentifyFormatValue )
{
return QgsRasterIdentifyResult( QGS_ERROR( tr( "Format not supported" ) ) );
}
if ( !extent().contains( point ) )
{
return noDataResult;
}
// TODO: use doubles instead of strings
// attention, value tool does his own tricks with grass identify() so it stops to refresh values outside extent or null values e.g.
bool ok;
double value = mRasterValue.value( point.x(), point.y(), &ok );
if ( !ok )
{
return QgsRasterIdentifyResult( QGS_ERROR( tr( "Cannot read data" ) ) );
}
// no data?
if ( std::isnan( value ) || qgsDoubleNear( value, mNoDataValue ) )
{
return noDataResult;
}
// Apply user no data
QgsRasterRangeList myNoDataRangeList = userNoDataValues( 1 );
if ( QgsRasterRange::contains( value, myNoDataRangeList ) )
{
return noDataResult;
}
results.insert( 1, value );
return QgsRasterIdentifyResult( QgsRaster::IdentifyFormatValue, results );
}
int QgsGrassRasterProvider::capabilities() const
{
int capability = QgsRasterDataProvider::Identify
| QgsRasterDataProvider::IdentifyValue
| QgsRasterDataProvider::Size;
return capability;
}
Qgis::DataType QgsGrassRasterProvider::dataType( int bandNo ) const
{
return sourceDataType( bandNo );
}
Qgis::DataType QgsGrassRasterProvider::sourceDataType( int bandNo ) const
{
Q_UNUSED( bandNo );
switch ( mGrassDataType )
{
case CELL_TYPE:
return Qgis::Int32;
case FCELL_TYPE:
return Qgis::Float32;
case DCELL_TYPE:
return Qgis::Float64;
}
return Qgis::UnknownDataType;
}
int QgsGrassRasterProvider::bandCount() const
{
// TODO
return 1;
}
int QgsGrassRasterProvider::colorInterpretation( int bandNo ) const
{
// TODO: avoid loading color table here or cache it
QList<QgsColorRampShader::ColorRampItem> ct = colorTable( bandNo );
if ( ct.size() > 0 )
{
return QgsRaster::ContinuousPalette;
}
return QgsRaster::GrayIndex;
}
QString QgsGrassRasterProvider::htmlMetadata()
{
QString myMetadata;
QStringList myList;
myList.append( "GISDBASE: " + mGisdbase );
myList.append( "LOCATION: " + mLocation );
myList.append( "MAPSET: " + mMapset );
myList.append( "MAP: " + mMapName );
QHash<QString, QString>::iterator i;
for ( i = mInfo.begin(); i != mInfo.end(); ++i )
{
myList.append( i.key() + " : " + i.value() );
}
myMetadata += QgsRasterDataProvider::makeTableCells( myList );
return myMetadata;
}
bool QgsGrassRasterProvider::isValid() const
{
return mValid;
}
void QgsGrassRasterProvider::setLastError( const QString &error )
{
mLastErrorTitle = tr( "GRASS raster provider" );
mLastError = error;
}
void QgsGrassRasterProvider::clearLastError()
{
mLastErrorTitle.clear();
mLastError.clear();
}
void QgsGrassRasterProvider::appendIfError( const QString &error )
{
if ( !error.isEmpty() )
{
appendError( ERR( error ) );
}
}
QString QgsGrassRasterProvider::lastErrorTitle()
{
return mLastErrorTitle;
}
QString QgsGrassRasterProvider::lastError()
{
return mLastError;
}
QString QgsGrassRasterProvider::name() const
{
return QStringLiteral( "grassraster" );
}
QString QgsGrassRasterProvider::description() const
{
return QStringLiteral( "GRASS %1 raster provider" ).arg( GRASS_VERSION_MAJOR );
}
QDateTime QgsGrassRasterProvider::dataTimestamp() const
{
QDateTime time;
QString mapset = mGisdbase + "/" + mLocation + "/" + mMapset;
QStringList dirs;
dirs << QStringLiteral( "cell" ) << QStringLiteral( "colr" );
Q_FOREACH ( const QString &dir, dirs )
{
QString path = mapset + "/" + dir + "/" + mMapName;
QFileInfo fi( path );
if ( fi.exists() && fi.lastModified() > time )
{
time = fi.lastModified();
}
}
QgsDebugMsg( "timestamp = " + time.toString() );
return time;
}
void QgsGrassRasterProvider::freeze()
{
mRasterValue.stop();
mValid = false;
}
void QgsGrassRasterProvider::thaw()
{
mValid = true;
}
//-------------------------------- QgsGrassRasterValue ----------------------------------------
QgsGrassRasterValue::~QgsGrassRasterValue()
{
stop();
}
void QgsGrassRasterValue::set( const QString &gisdbase, const QString &location, const QString &mapset, const QString &map )
{
mGisdbase = gisdbase;
mLocation = location;
mMapset = mapset;
mMapName = map;
}
void QgsGrassRasterValue::start()
{
if ( mProcess )
{
QgsDebugMsg( "already running" );
}
// TODO: catch exceptions
QString module = QgsGrass::qgisGrassModulePath() + "/qgis.g.info";
QStringList arguments;
arguments.append( QStringLiteral( "info=query" ) );
arguments.append( "rast=" + mMapName + "@" + mMapset );
try
{
mProcess = QgsGrass::startModule( mGisdbase, mLocation, mMapset, module, arguments, mGisrcFile );
}
catch ( QgsGrass::Exception &e )
{
QString error = e.what();
Q_UNUSED( error )
QgsDebugMsg( error );
}
}
void QgsGrassRasterValue::stop()
{
if ( mProcess )
{
QgsDebugMsg( "closing process" );
mProcess->closeWriteChannel();
mProcess->waitForFinished();
QgsDebugMsg( "process finished" );
delete mProcess;
mProcess = 0;
}
}
double QgsGrassRasterValue::value( double x, double y, bool *ok )
{
*ok = false;
double value = std::numeric_limits<double>::quiet_NaN();
if ( !mProcess )
{
start();
}
if ( !mProcess )
{
return value;
}
QString coor = QStringLiteral( "%1 %2\n" ).arg( QgsRasterBlock::printValue( x ),
QgsRasterBlock::printValue( y ) );
QgsDebugMsg( "coor : " + coor );
mProcess->write( coor.toLatin1() ); // how to flush, necessary?
mProcess->waitForReadyRead();
QString str = mProcess->readLine().trimmed();
QgsDebugMsg( "read from stdout : " + str );
// TODO: use doubles instead of strings
QStringList list = str.trimmed().split( QStringLiteral( ":" ) );
if ( list.size() == 2 )
{
if ( list[1] == QLatin1String( "error" ) ) return value;
value = list[1].toDouble( ok );
}
return value;
}