Fast track for first tiles

qgis · Jan 13, 2020 · 4d5b3f0 · 4d5b3f0
1 parent 0c2c133
commit 4d5b3f0
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Showing 2 changed files with 21 additions and 8 deletions.
diff --git a/src/providers/postgres/raster/qgspostgresrasterprovider.cpp b/src/providers/postgres/raster/qgspostgresrasterprovider.cpp
@@ -375,8 +375,8 @@ bool QgsPostgresRasterProvider::readBlock( int bandNo, const QgsRectangle &viewE
       }
     }
 
-    qDebug() << "Overview desired: " << desiredOverviewFactor << "found:" << overviewFactor << tableToQuery;
-    qDebug() << "View extent" << viewExtent.toString( 1 ) << width << height << minPixelSize;
+    //qDebug() << "Overview desired: " << desiredOverviewFactor << "found:" << overviewFactor << tableToQuery;
+    //qDebug() << "View extent" << viewExtent.toString( 1 ) << width << height << minPixelSize;
 
     // Get the the tiles we need to build the block
     const QString dataSql { QStringLiteral( "SELECT %3, ENCODE( ST_AsBinary( %1, TRUE ), 'hex') "
@@ -435,7 +435,7 @@ bool QgsPostgresRasterProvider::readBlock( int bandNo, const QgsRectangle &viewE
 
     GDALDataType gdalDataType { static_cast<GDALDataType>( sourceDataType( bandNo ) ) };
 
-    qDebug() << "Creating output raster: " << tilesExtent.toString() << tmpWidth << tmpHeight;
+    //qDebug() << "Creating output raster: " << tilesExtent.toString() << tmpWidth << tmpHeight;
 
     gdal::dataset_unique_ptr tmpDS { QgsGdalUtils::createSingleBandMemoryDataset(
                                        gdalDataType, tilesExtent, tmpWidth, tmpHeight, mCrs ) };
@@ -456,7 +456,7 @@ bool QgsPostgresRasterProvider::readBlock( int bandNo, const QgsRectangle &viewE
       const int xOff { static_cast<int>( std::round( ( tile.upperLeftX - tilesExtent.xMinimum() ) / tile.scaleX ) ) };
       const int yOff { static_cast<int>( std::round( ( tilesExtent.yMaximum() - tile.extent.yMaximum() ) / std::fabs( tile.scaleY ) ) )};
 
-      qDebug() << "Merging tile output raster: " << tile.tileId << xOff << yOff << tile.width << tile.height ;
+      //qDebug() << "Merging tile output raster: " << tile.tileId << xOff << yOff << tile.width << tile.height ;
 
       CPLErr err =  GDALRasterIO( GDALGetRasterBand( tmpDS.get(), 1 ),
                                   GF_Write,
@@ -799,10 +799,10 @@ bool QgsPostgresRasterProvider::init()
                                        QStringLiteral( "PostGIS" ), Qgis::Info );
             mSrcHasNoDataValue.append( false );
             mUseSrcNoDataValue.append( false );
+            nodataValue = std::numeric_limits<double>::min();
           }
           else
           {
-            mSrcNoDataValue.append( nodataValue );
             mSrcHasNoDataValue.append( true );
             mUseSrcNoDataValue.append( true );
           }

diff --git a/src/providers/postgres/raster/qgspostgresrastershareddata.cpp b/src/providers/postgres/raster/qgspostgresrastershareddata.cpp
@@ -37,18 +37,30 @@ QgsPostgresRasterSharedData::TilesResponse QgsPostgresRasterSharedData::tiles( c
 
   QgsPostgresRasterSharedData::TilesResponse result;
 
+  bool hasIndex { true };
+
   // First check for index existence
   if ( mSpatialIndexes.find( request.overviewFactor ) == mSpatialIndexes.end() )
   {
     // Create the index
     mSpatialIndexes.emplace( request.overviewFactor, new QgsGenericSpatialIndex<Tile>() );
     mTiles.emplace( request.overviewFactor, std::map<TileIdType, std::unique_ptr<Tile>>() );
     mLoadedIndexBounds[ request.overviewFactor] = QgsGeometry::fromRect( QgsRectangle() );
+    hasIndex = false;
   }
 
   // Now check if the requested extent was completely downloaded
   const QgsGeometry requestedRect { QgsGeometry::fromRect( request.extent ) };
-  if ( ! mLoadedIndexBounds[ request.overviewFactor].contains( requestedRect ) )
+
+  // Fast track for first tile (where index is empty)
+  if ( ! hasIndex )
+  {
+    if ( ! fetchTilesIndex( requestedRect, request ) )
+    {
+      return result;
+    }
+  }
+  else if ( ! mLoadedIndexBounds[ request.overviewFactor].contains( requestedRect ) )
   {
     // Fetch index
     const QgsGeometry geomDiff { requestedRect.difference( mLoadedIndexBounds[ request.overviewFactor] ) };
@@ -223,11 +235,12 @@ bool QgsPostgresRasterSharedData::fetchTilesIndex( const QgsGeometry &requestPol
     {
       mSpatialIndexes[ request.overviewFactor ]->insert( tile.get(), tile->extent );
       mTiles[ request.overviewFactor ][ tileId ] = std::move( tile );
-      qDebug() << "Tile added:" << request.overviewFactor << " ID: " << tileId << "extent " << extent.toString( 4 ) << upperleftx << upperlefty << tileWidth  << tileHeight <<  extent.width() << extent.height();
+      //qDebug() << "Tile added:" << request.overviewFactor << " ID: " << tileId << "extent " << extent.toString( 4 ) << upperleftx << upperlefty << tileWidth  << tileHeight <<  extent.width() << extent.height();
     }
     else
     {
-      qDebug() << "Tile already indexed:" << request.overviewFactor << " ID: " << tileId << "extent " << extent.toString( 4 ) << upperleftx << upperlefty << tileWidth  << tileHeight <<  extent.width() << extent.height();
+      // This should never happen!
+      //qDebug() << "Tile already indexed:" << request.overviewFactor << " ID: " << tileId << "extent " << extent.toString( 4 ) << upperleftx << upperlefty << tileWidth  << tileHeight <<  extent.width() << extent.height();
     }
   }
   return true;