QgsRasterBlock * QgsRasterProjector::block( int bandNo, QgsRectangle const & extent, int width, int height )
{
QgsDebugMsg( QString( "extent:\n%1" ).arg( extent.toString() ) );
QgsDebugMsg( QString( "width = %1 height = %2" ).arg( width ).arg( height ) );
if ( !mInput )
{
QgsDebugMsg( "Input not set" );
return new QgsRasterBlock();
}
if ( ! mSrcCRS.isValid() || ! mDestCRS.isValid() || mSrcCRS == mDestCRS )
{
QgsDebugMsg( "No projection necessary" );
return mInput->block( bandNo, extent, width, height );
}
mDestExtent = extent;
mDestRows = height;
mDestCols = width;
calc();
QgsDebugMsg( QString( "srcExtent:\n%1" ).arg( srcExtent().toString() ) );
QgsDebugMsg( QString( "srcCols = %1 srcRows = %2" ).arg( srcCols() ).arg( srcRows() ) );
// If we zoom out too much, projector srcRows / srcCols maybe 0, which can cause problems in providers
if ( srcRows() <= 0 || srcCols() <= 0 )
{
QgsDebugMsg( "Zero srcRows or srcCols" );
return new QgsRasterBlock();
}
QgsRasterBlock *inputBlock = mInput->block( bandNo, srcExtent(), srcCols(), srcRows() );
if ( !inputBlock || inputBlock->isEmpty() )
{
QgsDebugMsg( "No raster data!" );
delete inputBlock;
return new QgsRasterBlock();
}
qgssize pixelSize = QgsRasterBlock::typeSize( mInput->dataType( bandNo ) );
QgsRasterBlock *outputBlock;
if ( inputBlock->hasNoDataValue() )
{
outputBlock = new QgsRasterBlock( inputBlock->dataType(), width, height, inputBlock->noDataValue() );
}
else
{
outputBlock = new QgsRasterBlock( inputBlock->dataType(), width, height );
}
if ( !outputBlock->isValid() )
{
QgsDebugMsg( "Cannot create block" );
delete inputBlock;
return outputBlock;
}
// set output to no data, it should be fast
outputBlock->setIsNoData();
// No data: because isNoData()/setIsNoData() is slow with respect to simple memcpy,
// we use if only if necessary:
// 1) no data value exists (numerical) -> memcpy, not necessary isNoData()/setIsNoData()
// 2) no data value does not exist but it may contain no data (numerical no data bitmap)
// -> must use isNoData()/setIsNoData()
// 3) no data are not used (no no data value, no no data bitmap) -> simple memcpy
// 4) image - simple memcpy
// To copy no data values stored in bitmaps we have to use isNoData()/setIsNoData(),
// we cannot fill output block with no data because we use memcpy for data, not setValue().
bool doNoData = !QgsRasterBlock::typeIsNumeric( inputBlock->dataType() ) && inputBlock->hasNoData() && !inputBlock->hasNoDataValue();
const QgsCoordinateTransform* inverseCt = nullptr;
if ( !mApproximate )
{
inverseCt = QgsCoordinateTransformCache::instance()->transform( mDestCRS.authid(), mSrcCRS.authid(), mDestDatumTransform, mSrcDatumTransform );
}
outputBlock->setIsNoData();
int srcRow, srcCol;
for ( int i = 0; i < height; ++i )
{
for ( int j = 0; j < width; ++j )
{
bool inside = srcRowCol( i, j, &srcRow, &srcCol, inverseCt );
if ( !inside ) continue; // we have everything set to no data
qgssize srcIndex = ( qgssize )srcRow * mSrcCols + srcCol;
QgsDebugMsgLevel( QString( "row = %1 col = %2 srcRow = %3 srcCol = %4" ).arg( i ).arg( j ).arg( srcRow ).arg( srcCol ), 5 );
// isNoData() may be slow so we check doNoData first
if ( doNoData && inputBlock->isNoData( srcRow, srcCol ) )
{
outputBlock->setIsNoData( i, j );
continue;
}
qgssize destIndex = ( qgssize )i * width + j;
char *srcBits = inputBlock->bits( srcIndex );
char *destBits = outputBlock->bits( destIndex );
if ( !srcBits )
{
QgsDebugMsg( QString( "Cannot get input block data: row = %1 col = %2" ).arg( i ).arg( j ) );
continue;
}
if ( !destBits )
{
QgsDebugMsg( QString( "Cannot set output block data: srcRow = %1 srcCol = %2" ).arg( srcRow ).arg( srcCol ) );
continue;
}
memcpy( destBits, srcBits, pixelSize );
outputBlock->setIsData( i, j );
}
}
delete inputBlock;
return outputBlock;
}
void * QgsRasterProjector::readBlock( int bandNo, QgsRectangle const & extent, int width, int height )
{
QgsDebugMsg( QString( "extent:\n%1" ).arg( extent.toString() ) );
QgsDebugMsg( QString( "width = %1 height = %2" ).arg( width ).arg( height ) );
if ( !mInput ) return 0;
if ( ! mSrcCRS.isValid() || ! mDestCRS.isValid() || mSrcCRS == mDestCRS )
{
QgsDebugMsg( "No projection necessary" );
return mInput->block( bandNo, extent, width, height );
}
mDestExtent = extent;
mDestRows = height;
mDestCols = width;
calc();
QgsDebugMsg( QString( "srcExtent:\n%1" ).arg( srcExtent().toString() ) );
QgsDebugMsg( QString( "srcCols = %1 srcRows = %2" ).arg( srcCols() ).arg( srcRows() ) );
// If we zoom out too much, projector srcRows / srcCols maybe 0, which can cause problems in providers
if ( srcRows() <= 0 || srcCols() <= 0 )
{
return 0;
}
void * inputData = mInput->block( bandNo, srcExtent(), srcCols(), srcRows() );
if ( !inputData ) return 0;
size_t pixelSize = mInput->typeSize( mInput->dataType( bandNo ) ) / 8;
size_t inputSize = pixelSize * srcCols() * srcRows();
size_t outputSize = width * height * pixelSize;
void * outputData = malloc( outputSize );
// Check for allcoation error
if ( ! outputData )
{
QgsDebugMsg( QString( "Couldn't malloc %1 bytes!" ).arg( outputSize ) );
free( inputData );
return 0;
}
// TODO: fill by transparent
int srcRow, srcCol;
for ( int i = 0; i < height; ++i )
{
for ( int j = 0; j < width; ++j )
{
srcRowCol( i, j, &srcRow, &srcCol );
size_t srcIndex = pixelSize * ( srcRow * mSrcCols + srcCol );
size_t destIndex = pixelSize * ( i * width + j );
if ( srcIndex >= inputSize || destIndex >= outputSize ) continue; // should not happen
memcpy(( char* )outputData + destIndex, ( char* )inputData + srcIndex, pixelSize );
}
}
free( inputData );
return outputData;
}