QgsRasterCalculator::Result QgsRasterCalculator::processCalculation( QgsFeedback *feedback )
{
mLastError.clear();
//prepare search string / tree
std::unique_ptr< QgsRasterCalcNode > calcNode( QgsRasterCalcNode::parseRasterCalcString( mFormulaString, mLastError ) );
if ( !calcNode )
{
//error
return ParserError;
}
// Check input layers and bands
for ( const auto &entry : qgis::as_const( mRasterEntries ) )
{
if ( !entry.raster ) // no raster layer in entry
{
mLastError = QObject::tr( "No raster layer for entry %1" ).arg( entry.ref );
return InputLayerError;
}
if ( entry.bandNumber <= 0 || entry.bandNumber > entry.raster->bandCount() )
{
mLastError = QObject::tr( "Band number %1 is not valid for entry %2" ).arg( entry.bandNumber ).arg( entry.ref );
return BandError;
}
}
#ifdef HAVE_OPENCL
// Check for matrix nodes, GPU implementation does not support them
QList<const QgsRasterCalcNode *> nodeList;
if ( QgsOpenClUtils::enabled() && QgsOpenClUtils::available() && calcNode->findNodes( QgsRasterCalcNode::Type::tMatrix ).isEmpty() )
return processCalculationGPU( std::move( calcNode ), feedback );
#endif
//open output dataset for writing
GDALDriverH outputDriver = openOutputDriver();
if ( !outputDriver )
{
mLastError = QObject::tr( "Could not obtain driver for %1" ).arg( mOutputFormat );
return CreateOutputError;
}
gdal::dataset_unique_ptr outputDataset( openOutputFile( outputDriver ) );
if ( !outputDataset )
{
mLastError = QObject::tr( "Could not create output %1" ).arg( mOutputFile );
return CreateOutputError;
}
GDALSetProjection( outputDataset.get(), mOutputCrs.toWkt().toLocal8Bit().data() );
GDALRasterBandH outputRasterBand = GDALGetRasterBand( outputDataset.get(), 1 );
float outputNodataValue = -FLT_MAX;
GDALSetRasterNoDataValue( outputRasterBand, outputNodataValue );
// Check if we need to read the raster as a whole (which is memory inefficient
// and not interruptable by the user) by checking if any raster matrix nodes are
// in the expression
bool requiresMatrix = ! calcNode->findNodes( QgsRasterCalcNode::Type::tMatrix ).isEmpty();
// Take the fast route (process one line at a time) if we can
if ( ! requiresMatrix )
{
// Map of raster names -> blocks
std::map<QString, std::unique_ptr<QgsRasterBlock>> inputBlocks;
std::map<QString, QgsRasterCalculatorEntry> uniqueRasterEntries;
for ( const auto &r : calcNode->findNodes( QgsRasterCalcNode::Type::tRasterRef ) )
{
QString layerRef( r->toString().remove( 0, 1 ) );
layerRef.chop( 1 );
if ( ! inputBlocks.count( layerRef ) )
{
for ( const auto &ref : mRasterEntries )
{
if ( ref.ref == layerRef )
{
uniqueRasterEntries[layerRef] = ref;
inputBlocks[layerRef ] = qgis::make_unique<QgsRasterBlock>();
}
}
}
}
//read / write line by line
QMap<QString, QgsRasterBlock * > _rasterData;
// Cast to float
std::vector<float> castedResult;
castedResult.reserve( static_cast<size_t>( mNumOutputColumns ) );
auto rowHeight = mOutputRectangle.height() / mNumOutputRows;
for ( size_t row = 0; row < static_cast<size_t>( mNumOutputRows ); ++row )
{
if ( feedback )
{
feedback->setProgress( 100.0 * static_cast< double >( row ) / mNumOutputRows );
}
if ( feedback && feedback->isCanceled() )
{
break;
}
// Calculates the rect for a single row read
QgsRectangle rect( mOutputRectangle );
rect.setYMaximum( rect.yMaximum() - rowHeight * row );
rect.setYMinimum( rect.yMaximum() - rowHeight );
// Read rows into input blocks
for ( auto &layerRef : inputBlocks )
{
QgsRasterCalculatorEntry ref = uniqueRasterEntries[layerRef.first];
if ( uniqueRasterEntries[layerRef.first].raster->crs() != mOutputCrs )
{
QgsRasterProjector proj;
proj.setCrs( ref.raster->crs(), mOutputCrs );
proj.setInput( ref.raster->dataProvider() );
proj.setPrecision( QgsRasterProjector::Exact );
layerRef.second.reset( proj.block( ref.bandNumber, rect, mNumOutputColumns, 1 ) );
}
else
{
inputBlocks[layerRef.first].reset( ref.raster->dataProvider()->block( ref.bandNumber, rect, mNumOutputColumns, 1 ) );
}
}
QgsRasterMatrix resultMatrix;
resultMatrix.setNodataValue( outputNodataValue );
_rasterData.clear();
for ( const auto &layerRef : inputBlocks )
{
_rasterData.insert( layerRef.first, inputBlocks[layerRef.first].get() );
}
if ( calcNode->calculate( _rasterData, resultMatrix, 0 ) )
{
// write scanline to the dataset
for ( size_t i = 0; i < static_cast<size_t>( mNumOutputColumns ); i++ )
{
castedResult[i] = static_cast<float>( resultMatrix.data()[i] );
}
if ( GDALRasterIO( outputRasterBand, GF_Write, 0, row, mNumOutputColumns, 1, castedResult.data(), mNumOutputColumns, 1, GDT_Float32, 0, 0 ) != CE_None )
{
QgsDebugMsg( QStringLiteral( "RasterIO error!" ) );
}
}
}
if ( feedback )
{
feedback->setProgress( 100.0 );
}
}
else // Original code (memory inefficient route)
{
QMap< QString, QgsRasterBlock * > inputBlocks;
QVector<QgsRasterCalculatorEntry>::const_iterator it = mRasterEntries.constBegin();
for ( ; it != mRasterEntries.constEnd(); ++it )
{
std::unique_ptr< QgsRasterBlock > block;
// if crs transform needed
if ( it->raster->crs() != mOutputCrs )
{
QgsRasterProjector proj;
proj.setCrs( it->raster->crs(), mOutputCrs );
proj.setInput( it->raster->dataProvider() );
proj.setPrecision( QgsRasterProjector::Exact );
QgsRasterBlockFeedback *rasterBlockFeedback = new QgsRasterBlockFeedback();
QObject::connect( feedback, &QgsFeedback::canceled, rasterBlockFeedback, &QgsRasterBlockFeedback::cancel );
block.reset( proj.block( it->bandNumber, mOutputRectangle, mNumOutputColumns, mNumOutputRows, rasterBlockFeedback ) );
if ( rasterBlockFeedback->isCanceled() )
{
qDeleteAll( inputBlocks );
return Canceled;
}
}
else
{
block.reset( it->raster->dataProvider()->block( it->bandNumber, mOutputRectangle, mNumOutputColumns, mNumOutputRows ) );
}
if ( block->isEmpty() )
{
mLastError = QObject::tr( "Could not allocate required memory for %1" ).arg( it->ref );
qDeleteAll( inputBlocks );
return MemoryError;
}
inputBlocks.insert( it->ref, block.release() );
}
QgsRasterMatrix resultMatrix;
resultMatrix.setNodataValue( outputNodataValue );
//read / write line by line
for ( int i = 0; i < mNumOutputRows; ++i )
{
if ( feedback )
{
feedback->setProgress( 100.0 * static_cast< double >( i ) / mNumOutputRows );
}
if ( feedback && feedback->isCanceled() )
{
break;
}
if ( calcNode->calculate( inputBlocks, resultMatrix, i ) )
{
bool resultIsNumber = resultMatrix.isNumber();
float *calcData = new float[mNumOutputColumns];
for ( int j = 0; j < mNumOutputColumns; ++j )
{
calcData[j] = ( float )( resultIsNumber ? resultMatrix.number() : resultMatrix.data()[j] );
}
//write scanline to the dataset
if ( GDALRasterIO( outputRasterBand, GF_Write, 0, i, mNumOutputColumns, 1, calcData, mNumOutputColumns, 1, GDT_Float32, 0, 0 ) != CE_None )
{
QgsDebugMsg( QStringLiteral( "RasterIO error!" ) );
}
delete[] calcData;
}
}
if ( feedback )
{
feedback->setProgress( 100.0 );
}
//close datasets and release memory
calcNode.reset();
qDeleteAll( inputBlocks );
inputBlocks.clear();
}
if ( feedback && feedback->isCanceled() )
{
//delete the dataset without closing (because it is faster)
gdal::fast_delete_and_close( outputDataset, outputDriver, mOutputFile );
return Canceled;
}
return Success;
}
int QgsRasterCalculator::processCalculation( QProgressDialog* p )
{
//prepare search string / tree
QString errorString;
QgsRasterCalcNode* calcNode = QgsRasterCalcNode::parseRasterCalcString( mFormulaString, errorString );
if ( !calcNode )
{
//error
return static_cast<int>( ParserError );
}
QMap< QString, QgsRasterBlock* > inputBlocks;
QVector<QgsRasterCalculatorEntry>::const_iterator it = mRasterEntries.constBegin();
for ( ; it != mRasterEntries.constEnd(); ++it )
{
if ( !it->raster ) // no raster layer in entry
{
delete calcNode;
qDeleteAll( inputBlocks );
return static_cast< int >( InputLayerError );
}
QgsRasterBlock* block = nullptr;
// if crs transform needed
if ( it->raster->crs() != mOutputCrs )
{
QgsRasterProjector proj;
proj.setCRS( it->raster->crs(), mOutputCrs );
proj.setInput( it->raster->dataProvider() );
proj.setPrecision( QgsRasterProjector::Exact );
block = proj.block( it->bandNumber, mOutputRectangle, mNumOutputColumns, mNumOutputRows );
}
else
{
block = it->raster->dataProvider()->block( it->bandNumber, mOutputRectangle, mNumOutputColumns, mNumOutputRows );
}
if ( block->isEmpty() )
{
delete block;
delete calcNode;
qDeleteAll( inputBlocks );
return static_cast<int>( MemoryError );
}
inputBlocks.insert( it->ref, block );
}
//open output dataset for writing
GDALDriverH outputDriver = openOutputDriver();
if ( !outputDriver )
{
return static_cast< int >( CreateOutputError );
}
GDALDatasetH outputDataset = openOutputFile( outputDriver );
GDALSetProjection( outputDataset, mOutputCrs.toWkt().toLocal8Bit().data() );
GDALRasterBandH outputRasterBand = GDALGetRasterBand( outputDataset, 1 );
float outputNodataValue = -FLT_MAX;
GDALSetRasterNoDataValue( outputRasterBand, outputNodataValue );
if ( p )
{
p->setMaximum( mNumOutputRows );
}
QgsRasterMatrix resultMatrix;
resultMatrix.setNodataValue( outputNodataValue );
//read / write line by line
for ( int i = 0; i < mNumOutputRows; ++i )
{
if ( p )
{
p->setValue( i );
}
if ( p && p->wasCanceled() )
{
break;
}
if ( calcNode->calculate( inputBlocks, resultMatrix, i ) )
{
bool resultIsNumber = resultMatrix.isNumber();
float* calcData = new float[mNumOutputColumns];
for ( int j = 0; j < mNumOutputColumns; ++j )
{
calcData[j] = ( float )( resultIsNumber ? resultMatrix.number() : resultMatrix.data()[j] );
}
//write scanline to the dataset
if ( GDALRasterIO( outputRasterBand, GF_Write, 0, i, mNumOutputColumns, 1, calcData, mNumOutputColumns, 1, GDT_Float32, 0, 0 ) != CE_None )
{
qWarning( "RasterIO error!" );
}
delete[] calcData;
}
}
if ( p )
{
p->setValue( mNumOutputRows );
}
//close datasets and release memory
delete calcNode;
qDeleteAll( inputBlocks );
inputBlocks.clear();
if ( p && p->wasCanceled() )
{
//delete the dataset without closing (because it is faster)
GDALDeleteDataset( outputDriver, TO8F( mOutputFile ) );
return static_cast< int >( Cancelled );
}
GDALClose( outputDataset );
return static_cast< int >( Success );
}
QgsRasterCalculator::Result QgsRasterCalculator::processCalculationGPU( std::unique_ptr< QgsRasterCalcNode > calcNode, QgsFeedback *feedback )
{
QString cExpression( calcNode->toString( true ) );
QList<const QgsRasterCalcNode *> nodeList( calcNode->findNodes( QgsRasterCalcNode::Type::tRasterRef ) );
QSet<QString> capturedTexts;
for ( const auto &r : qgis::as_const( nodeList ) )
{
QString s( r->toString().remove( 0, 1 ) );
s.chop( 1 );
capturedTexts.insert( s );
}
// Extract all references
struct LayerRef
{
QString name;
int band;
QgsRasterLayer *layer = nullptr;
QString varName;
QString typeName;
size_t index;
size_t bufferSize;
size_t dataSize;
};
// Collects all layers, band, name, varName and size information
std::vector<LayerRef> inputRefs;
size_t refCounter = 0;
for ( const auto &r : capturedTexts )
{
if ( r.startsWith( '"' ) )
continue;
QStringList parts( r.split( '@' ) );
if ( parts.count() != 2 )
continue;
bool ok = false;
LayerRef entry;
entry.name = r;
entry.band = parts[1].toInt( &ok );
for ( const auto &ref : mRasterEntries )
{
if ( ref.ref == entry.name )
entry.layer = ref.raster;
}
if ( !( entry.layer && entry.layer->dataProvider() && ok ) )
continue;
entry.dataSize = entry.layer->dataProvider()->dataTypeSize( entry.band );
switch ( entry.layer->dataProvider()->dataType( entry.band ) )
{
case Qgis::DataType::Byte:
entry.typeName = QStringLiteral( "unsigned char" );
break;
case Qgis::DataType::UInt16:
entry.typeName = QStringLiteral( "unsigned int" );
break;
case Qgis::DataType::Int16:
entry.typeName = QStringLiteral( "short" );
break;
case Qgis::DataType::UInt32:
entry.typeName = QStringLiteral( "unsigned int" );
break;
case Qgis::DataType::Int32:
entry.typeName = QStringLiteral( "int" );
break;
case Qgis::DataType::Float32:
entry.typeName = QStringLiteral( "float" );
break;
// FIXME: not sure all OpenCL implementations support double
// maybe safer to fall back to the CPU implementation
// after a compatibility check
case Qgis::DataType::Float64:
entry.typeName = QStringLiteral( "double" );
break;
default:
return BandError;
}
entry.bufferSize = entry.dataSize * mNumOutputColumns;
entry.index = refCounter;
entry.varName = QStringLiteral( "input_raster_%1_band_%2" )
.arg( refCounter++ )
.arg( entry.band );
inputRefs.push_back( entry );
}
// Prepare context and queue
cl::Context ctx( QgsOpenClUtils::context() );
cl::CommandQueue queue( QgsOpenClUtils::commandQueue() );
// Create the C expression
std::vector<cl::Buffer> inputBuffers;
inputBuffers.reserve( inputRefs.size() );
QStringList inputArgs;
for ( const auto &ref : inputRefs )
{
cExpression.replace( QStringLiteral( "\"%1\"" ).arg( ref.name ), QStringLiteral( "%1[i]" ).arg( ref.varName ) );
inputArgs.append( QStringLiteral( "__global %1 *%2" )
.arg( ref.typeName )
.arg( ref.varName ) );
inputBuffers.push_back( cl::Buffer( ctx, CL_MEM_READ_ONLY, ref.bufferSize, nullptr, nullptr ) );
}
//qDebug() << cExpression;
// Create the program
QString programTemplate( R"CL(
// Inputs:
##INPUT_DESC##
// Expression: ##EXPRESSION_ORIGINAL##
__kernel void rasterCalculator( ##INPUT##
__global float *resultLine
)
{
// Get the index of the current element
const int i = get_global_id(0);
// Expression
resultLine[i] = ##EXPRESSION##;
}
)CL" );
QStringList inputDesc;
for ( const auto &ref : inputRefs )
{
inputDesc.append( QStringLiteral( " // %1 = %2" ).arg( ref.varName ).arg( ref.name ) );
}
programTemplate = programTemplate.replace( QStringLiteral( "##INPUT_DESC##" ), inputDesc.join( '\n' ) );
programTemplate = programTemplate.replace( QStringLiteral( "##INPUT##" ), inputArgs.length() ? ( inputArgs.join( ',' ).append( ',' ) ) : QChar( ' ' ) );
programTemplate = programTemplate.replace( QStringLiteral( "##EXPRESSION##" ), cExpression );
programTemplate = programTemplate.replace( QStringLiteral( "##EXPRESSION_ORIGINAL##" ), calcNode->toString( ) );
// qDebug() << programTemplate;
// Create a program from the kernel source
cl::Program program( QgsOpenClUtils::buildProgram( programTemplate, QgsOpenClUtils::ExceptionBehavior::Throw ) );
// Create the buffers, output is float32 (4 bytes)
// We assume size of float = 4 because that's the size used by OpenCL and IEEE 754
Q_ASSERT( sizeof( float ) == 4 );
std::size_t resultBufferSize( 4 * static_cast<size_t>( mNumOutputColumns ) );
cl::Buffer resultLineBuffer( ctx, CL_MEM_WRITE_ONLY,
resultBufferSize, nullptr, nullptr );
auto kernel = cl::Kernel( program, "rasterCalculator" );
for ( unsigned int i = 0; i < inputBuffers.size() ; i++ )
{
kernel.setArg( i, inputBuffers.at( i ) );
}
kernel.setArg( static_cast<unsigned int>( inputBuffers.size() ), resultLineBuffer );
QgsOpenClUtils::CPLAllocator<float> resultLine( static_cast<size_t>( mNumOutputColumns ) );
//open output dataset for writing
GDALDriverH outputDriver = openOutputDriver();
if ( !outputDriver )
{
mLastError = QObject::tr( "Could not obtain driver for %1" ).arg( mOutputFormat );
return CreateOutputError;
}
gdal::dataset_unique_ptr outputDataset( openOutputFile( outputDriver ) );
if ( !outputDataset )
{
mLastError = QObject::tr( "Could not create output %1" ).arg( mOutputFile );
return CreateOutputError;
}
GDALSetProjection( outputDataset.get(), mOutputCrs.toWkt().toLocal8Bit().data() );
GDALRasterBandH outputRasterBand = GDALGetRasterBand( outputDataset.get(), 1 );
if ( !outputRasterBand )
return BandError;
// Input block (buffer)
std::unique_ptr<QgsRasterBlock> block;
// Run kernel on all scanlines
auto rowHeight = mOutputRectangle.height() / mNumOutputRows;
for ( int line = 0; line < mNumOutputRows; line++ )
{
if ( feedback && feedback->isCanceled() )
{
break;
}
if ( feedback )
{
feedback->setProgress( 100.0 * static_cast< double >( line ) / mNumOutputRows );
}
// Read lines from rasters into the buffers
for ( const auto &ref : inputRefs )
{
// Read one row
QgsRectangle rect( mOutputRectangle );
rect.setYMaximum( rect.yMaximum() - rowHeight * line );
rect.setYMinimum( rect.yMaximum() - rowHeight );
// TODO: check if this is too slow
// if crs transform needed
if ( ref.layer->crs() != mOutputCrs )
{
QgsRasterProjector proj;
proj.setCrs( ref.layer->crs(), mOutputCrs );
proj.setInput( ref.layer->dataProvider() );
proj.setPrecision( QgsRasterProjector::Exact );
block.reset( proj.block( ref.band, rect, mNumOutputColumns, 1 ) );
}
else
{
block.reset( ref.layer->dataProvider()->block( ref.band, rect, mNumOutputColumns, 1 ) );
}
//for ( int i = 0; i < mNumOutputColumns; i++ )
// qDebug() << "Input: " << line << i << ref.varName << " = " << block->value( 0, i );
//qDebug() << "Writing buffer " << ref.index;
Q_ASSERT( ref.bufferSize == static_cast<size_t>( block->data().size( ) ) );
queue.enqueueWriteBuffer( inputBuffers[ref.index], CL_TRUE, 0,
ref.bufferSize, block->bits() );
}
// Run the kernel
queue.enqueueNDRangeKernel(
kernel,
0,
cl::NDRange( mNumOutputColumns )
);
// Write the result
queue.enqueueReadBuffer( resultLineBuffer, CL_TRUE, 0,
resultBufferSize, resultLine.get() );
//for ( int i = 0; i < mNumOutputColumns; i++ )
// qDebug() << "Output: " << line << i << " = " << resultLine[i];
if ( GDALRasterIO( outputRasterBand, GF_Write, 0, line, mNumOutputColumns, 1, resultLine.get(), mNumOutputColumns, 1, GDT_Float32, 0, 0 ) != CE_None )
{
return CreateOutputError;
}
}
if ( feedback && feedback->isCanceled() )
{
//delete the dataset without closing (because it is faster)
gdal::fast_delete_and_close( outputDataset, outputDriver, mOutputFile );
return Canceled;
}
inputBuffers.clear();
return Success;
}
