QgsRasterIdentifyResult QgsGrassRasterProvider::identify( const QgsPoint & thePoint, QgsRaster::IdentifyFormat theFormat, const QgsRectangle &theExtent, int theWidth, int theHeight, int /*theDpi*/ )
{
  Q_UNUSED( theExtent );
  Q_UNUSED( theWidth );
  Q_UNUSED( theHeight );
  QgsDebugMsg( "Entered" );
  QMap<int, QVariant> results;
  QMap<int, QVariant> noDataResults;
  noDataResults.insert( 1, QVariant() );
  QgsRasterIdentifyResult noDataResult( QgsRaster::IdentifyFormatValue, results );

  if ( theFormat != QgsRaster::IdentifyFormatValue )
  {
    return QgsRasterIdentifyResult( QGS_ERROR( tr( "Format not supported" ) ) );
  }

  if ( !extent().contains( thePoint ) )
  {
    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( thePoint.x(), thePoint.y(), &ok );

  if ( !ok )
  {
    return QgsRasterIdentifyResult( QGS_ERROR( tr( "Cannot read data" ) ) );
  }

  // no data?
  if ( qIsNaN( 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 );
}
Example #2
0
QgsRasterBlock *QgsRasterDataProvider::block( int bandNo, QgsRectangle  const &boundingBox, int width, int height, QgsRasterBlockFeedback *feedback )
{
  QgsDebugMsgLevel( QString( "bandNo = %1 width = %2 height = %3" ).arg( bandNo ).arg( width ).arg( height ), 4 );
  QgsDebugMsgLevel( QString( "boundingBox = %1" ).arg( boundingBox.toString() ), 4 );

  QgsRasterBlock *block = new QgsRasterBlock( dataType( bandNo ), width, height );
  if ( sourceHasNoDataValue( bandNo ) && useSourceNoDataValue( bandNo ) )
  {
    block->setNoDataValue( sourceNoDataValue( bandNo ) );
  }

  if ( block->isEmpty() )
  {
    QgsDebugMsg( "Couldn't create raster block" );
    return block;
  }

  // Read necessary extent only
  QgsRectangle tmpExtent = extent().intersect( &boundingBox );

  if ( tmpExtent.isEmpty() )
  {
    QgsDebugMsg( "Extent outside provider extent" );
    block->setIsNoData();
    return block;
  }

  double xRes = boundingBox.width() / width;
  double yRes = boundingBox.height() / height;
  double tmpXRes, tmpYRes;
  double providerXRes = 0;
  double providerYRes = 0;
  if ( capabilities() & Size )
  {
    providerXRes = extent().width() / xSize();
    providerYRes = extent().height() / ySize();
    tmpXRes = std::max( providerXRes, xRes );
    tmpYRes = std::max( providerYRes, yRes );
    if ( qgsDoubleNear( tmpXRes, xRes ) ) tmpXRes = xRes;
    if ( qgsDoubleNear( tmpYRes, yRes ) ) tmpYRes = yRes;
  }
  else
  {
    tmpXRes = xRes;
    tmpYRes = yRes;
  }

  if ( tmpExtent != boundingBox ||
       tmpXRes > xRes || tmpYRes > yRes )
  {
    // Read smaller extent or lower resolution

    if ( !extent().contains( boundingBox ) )
    {
      QRect subRect = QgsRasterBlock::subRect( boundingBox, width, height, extent() );
      block->setIsNoDataExcept( subRect );
    }

    // Calculate row/col limits (before tmpExtent is aligned)
    int fromRow = std::round( ( boundingBox.yMaximum() - tmpExtent.yMaximum() ) / yRes );
    int toRow = std::round( ( boundingBox.yMaximum() - tmpExtent.yMinimum() ) / yRes ) - 1;
    int fromCol = std::round( ( tmpExtent.xMinimum() - boundingBox.xMinimum() ) / xRes );
    int toCol = std::round( ( tmpExtent.xMaximum() - boundingBox.xMinimum() ) / xRes ) - 1;

    QgsDebugMsgLevel( QString( "fromRow = %1 toRow = %2 fromCol = %3 toCol = %4" ).arg( fromRow ).arg( toRow ).arg( fromCol ).arg( toCol ), 4 );

    if ( fromRow < 0 || fromRow >= height || toRow < 0 || toRow >= height ||
         fromCol < 0 || fromCol >= width || toCol < 0 || toCol >= width )
    {
      // Should not happen
      QgsDebugMsg( "Row or column limits out of range" );
      return block;
    }

    // If lower source resolution is used, the extent must beS aligned to original
    // resolution to avoid possible shift due to resampling
    if ( tmpXRes > xRes )
    {
      int col = std::floor( ( tmpExtent.xMinimum() - extent().xMinimum() ) / providerXRes );
      tmpExtent.setXMinimum( extent().xMinimum() + col * providerXRes );
      col = std::ceil( ( tmpExtent.xMaximum() - extent().xMinimum() ) / providerXRes );
      tmpExtent.setXMaximum( extent().xMinimum() + col * providerXRes );
    }
    if ( tmpYRes > yRes )
    {
      int row = std::floor( ( extent().yMaximum() - tmpExtent.yMaximum() ) / providerYRes );
      tmpExtent.setYMaximum( extent().yMaximum() - row * providerYRes );
      row = std::ceil( ( extent().yMaximum() - tmpExtent.yMinimum() ) / providerYRes );
      tmpExtent.setYMinimum( extent().yMaximum() - row * providerYRes );
    }
    int tmpWidth = std::round( tmpExtent.width() / tmpXRes );
    int tmpHeight = std::round( tmpExtent.height() / tmpYRes );
    tmpXRes = tmpExtent.width() / tmpWidth;
    tmpYRes = tmpExtent.height() / tmpHeight;

    QgsDebugMsgLevel( QString( "Reading smaller block tmpWidth = %1 height = %2" ).arg( tmpWidth ).arg( tmpHeight ), 4 );
    QgsDebugMsgLevel( QString( "tmpExtent = %1" ).arg( tmpExtent.toString() ), 4 );

    QgsRasterBlock *tmpBlock = new QgsRasterBlock( dataType( bandNo ), tmpWidth, tmpHeight );
    if ( sourceHasNoDataValue( bandNo ) && useSourceNoDataValue( bandNo ) )
    {
      tmpBlock->setNoDataValue( sourceNoDataValue( bandNo ) );
    }

    readBlock( bandNo, tmpExtent, tmpWidth, tmpHeight, tmpBlock->bits(), feedback );

    int pixelSize = dataTypeSize( bandNo );

    double xMin = boundingBox.xMinimum();
    double yMax = boundingBox.yMaximum();
    double tmpXMin = tmpExtent.xMinimum();
    double tmpYMax = tmpExtent.yMaximum();

    for ( int row = fromRow; row <= toRow; row++ )
    {
      double y = yMax - ( row + 0.5 ) * yRes;
      int tmpRow = std::floor( ( tmpYMax - y ) / tmpYRes );

      for ( int col = fromCol; col <= toCol; col++ )
      {
        double x = xMin + ( col + 0.5 ) * xRes;
        int tmpCol = std::floor( ( x - tmpXMin ) / tmpXRes );

        if ( tmpRow < 0 || tmpRow >= tmpHeight || tmpCol < 0 || tmpCol >= tmpWidth )
        {
          QgsDebugMsg( "Source row or column limits out of range" );
          block->setIsNoData(); // so that the problem becomes obvious and fixed
          delete tmpBlock;
          return block;
        }

        qgssize tmpIndex = static_cast< qgssize >( tmpRow ) * static_cast< qgssize >( tmpWidth ) + tmpCol;
        qgssize index = row * static_cast< qgssize >( width ) + col;

        char *tmpBits = tmpBlock->bits( tmpIndex );
        char *bits = block->bits( index );
        if ( !tmpBits )
        {
          QgsDebugMsg( QString( "Cannot get input block data tmpRow = %1 tmpCol = %2 tmpIndex = %3." ).arg( tmpRow ).arg( tmpCol ).arg( tmpIndex ) );
          continue;
        }
        if ( !bits )
        {
          QgsDebugMsg( "Cannot set output block data." );
          continue;
        }
        memcpy( bits, tmpBits, pixelSize );
      }
    }

    delete tmpBlock;
  }
  else
  {
    readBlock( bandNo, boundingBox, width, height, block->bits(), feedback );
  }

  // apply scale and offset
  block->applyScaleOffset( bandScale( bandNo ), bandOffset( bandNo ) );
  // apply user no data values
  block->applyNoDataValues( userNoDataValues( bandNo ) );
  return block;
}