PG raster: make wkb parser more flexible

elpaso · elpaso · commit e9b58cc1e6e5 · 2020-01-15T11:21:50.000+01:00
diff --git a/src/providers/postgres/raster/qgspostgresrastershareddata.cpp b/src/providers/postgres/raster/qgspostgresrastershareddata.cpp
@@ -261,5 +261,5 @@ QgsPostgresRasterSharedData::Tile::Tile( const QgsPostgresRasterSharedData::Tile
 
 QByteArray QgsPostgresRasterSharedData::Tile::bandData( int bandNo ) const
 {
-  return QgsPostgresRasterUtils::parseWkb( data, bandNo )[ QStringLiteral( "data" )].toByteArray();
+  return QgsPostgresRasterUtils::parseWkb( data, bandNo )[ QStringLiteral( "band%1" ).arg( bandNo )].toByteArray();
 }
diff --git a/src/providers/postgres/raster/qgspostgresrasterutils.cpp b/src/providers/postgres/raster/qgspostgresrasterutils.cpp
@@ -14,6 +14,7 @@
  *                                                                         *
  ***************************************************************************/
 
+
 #include "qgspostgresrasterutils.h"
 #include "qgsmessagelog.h"
 
@@ -121,6 +122,7 @@ QVariantMap QgsPostgresRasterUtils::parseWkb( const QByteArray &wkb, int bandNo
         pxSize = 8;
         break;
       default:
+        result[ QStringLiteral( "nodata" ) ] = std::numeric_limits<double>::min();
         QgsMessageLog::logMessage( QStringLiteral( "Unsupported pixel type: %1" )
                                    .arg( result[ QStringLiteral( "pxType" ) ].toInt() ), QStringLiteral( "PostGIS" ), Qgis::Critical );
 
@@ -137,19 +139,19 @@ QVariantMap QgsPostgresRasterUtils::parseWkb( const QByteArray &wkb, int bandNo
     return result;
   }
 
-  // Read first band
-  readBandHeader( );
-  // Read other bands
-  for ( int i = 2; i <= bandNo; ++i )
+  // Read bands (all bands if bandNo is 0)
+  for ( unsigned int bandCnt = 1; bandCnt <= ( bandNo == 0 ? nBands : static_cast<unsigned int>( bandNo ) ); ++bandCnt )
   {
-    offset += result[ QStringLiteral( "dataSize" ) ].toInt();
     readBandHeader( );
+    if ( bandNo == 0 || static_cast<unsigned int>( bandNo ) == bandCnt )
+    {
+      result[ QStringLiteral( "band%1" ).arg( bandCnt )] = wkb.mid( offset, result[ QStringLiteral( "dataSize" ) ].toInt() );
+    }
+    else
+    {
+      // Skip
+    }
+    offset += result[ QStringLiteral( "dataSize" ) ].toInt();
   }
-
-  // Check we did the math good
-  Q_ASSERT( result[ QStringLiteral( "dataSize" ) ].toInt() == result[ QStringLiteral( "width" ) ].toInt() * result[ QStringLiteral( "height" ) ].toInt() * result[ QStringLiteral( "pxSize" ) ].toInt( ) );
-
-  result[ QStringLiteral( "data" )] = wkb.mid( offset, result[ QStringLiteral( "dataSize" ) ].toInt() );
-
   return result;
 }
diff --git a/src/providers/postgres/raster/qgspostgresrasterutils.h b/src/providers/postgres/raster/qgspostgresrasterutils.h
@@ -22,8 +22,11 @@
 struct QgsPostgresRasterUtils
 {
 
-  //! Parses a WKB raster hex and returns information as a variant map
-  static QVariantMap parseWkb( const QByteArray &wkb, int bandNo = 1 );
+  /**
+   * Parses a \a wkb raster hex and returns information as a variant map
+   * for a particular \a bandNo or for all bands if bandNo is 0
+   */
+  static QVariantMap parseWkb( const QByteArray &wkb, int bandNo = 0 );
 
 };
 

Original file line number	Diff line number	Diff line change
`@@ -261,5 +261,5 @@ QgsPostgresRasterSharedData::Tile::Tile( const QgsPostgresRasterSharedData::Tile`
`261`	`261`
`262`	`262`	`QByteArray QgsPostgresRasterSharedData::Tile::bandData( int bandNo ) const`
`263`	`263`	`{`
`264`		`- return QgsPostgresRasterUtils::parseWkb( data, bandNo )[ QStringLiteral( "data" )].toByteArray();`
	`264`	`+ return QgsPostgresRasterUtils::parseWkb( data, bandNo )[ QStringLiteral( "band%1" ).arg( bandNo )].toByteArray();`
`265`	`265`	`}`