Move determination of tiles in ranges to QgsTileMatrixSet

This gives more flexibility in future to handle known missing tiles or
other special circumstances (eg falling back to lower
zoom level tiles from the matrix set in certain circumstances)

python/core/auto_generated/qgstiles.sip.in

@@ -365,6 +365,13 @@ Returns the scale to tile zoom method.
 Sets the scale to tile zoom method.
 
 .. seealso:: :py:func:`scaleToTileZoomMethod`
+%End
+
+    QVector<QgsTileXYZ> tilesInRange( QgsTileRange range, int zoomLevel ) const;
+%Docstring
+Returns a list of tiles in the given tile range.
+
+.. versionadded:: 3.32
 %End
 
 };

src/core/qgstiles.cpp

@@ -398,3 +398,21 @@ QDomElement QgsTileMatrixSet::writeXml( QDomDocument &document, const QgsReadWri
 
   return setElement;
 }
+
+QVector<QgsTileXYZ> QgsTileMatrixSet::tilesInRange( QgsTileRange range, int zoomLevel ) const
+{
+  QVector<QgsTileXYZ> tiles;
+  tiles.reserve( static_cast< std::size_t>( range.endColumn() - range.startColumn() + 1 ) * ( range.endRow() - range.startRow() + 1 ) );
+
+  const QgsTileMatrix &matrix = mTileMatrices.value( zoomLevel );
+
+  for ( int tileRow = range.startRow(); tileRow <= range.endRow(); ++tileRow )
+  {
+    for ( int tileColumn = range.startColumn(); tileColumn <= range.endColumn(); ++tileColumn )
+    {
+      tiles.append( QgsTileXYZ( tileColumn, tileRow, zoomLevel ) );
+    }
+  }
+  return tiles;
+}
+

src/core/qgstiles.h

@@ -376,6 +376,13 @@ class CORE_EXPORT QgsTileMatrixSet
      */
     void setScaleToTileZoomMethod( Qgis::ScaleToTileZoomLevelMethod method ) { mScaleToTileZoomMethod = method; }
 
+    /**
+     * Returns a list of tiles in the given tile range.
+     *
+     * \since QGIS 3.32
+     */
+    QVector<QgsTileXYZ> tilesInRange( QgsTileRange range, int zoomLevel ) const;
+
   private:
 
     // Usually corresponds to zoom level 0, even if that zoom level is NOT present in the actual tile matrices for this set

src/core/vectortile/qgsvectortileloader.cpp

@@ -39,7 +39,7 @@ QgsVectorTileLoader::QgsVectorTileLoader( const QgsVectorTileDataProvider *provi
   }
 
   QgsDebugMsgLevel( QStringLiteral( "Starting network loader" ), 2 );
-  QVector<QgsTileXYZ> tiles = QgsVectorTileUtils::tilesInRange( range, zoomLevel );
+  QVector<QgsTileXYZ> tiles = tileMatrixSet.tilesInRange( range, zoomLevel );
   QgsVectorTileUtils::sortTilesByDistanceFromCenter( tiles, viewCenter );
   for ( QgsTileXYZ id : std::as_const( tiles ) )
   {
@@ -152,7 +152,7 @@ QList<QgsVectorTileRawData> QgsVectorTileLoader::blockingFetchTileRawData( const
   if ( feedback && feedback->isCanceled() )
     return {};
 
-  QVector<QgsTileXYZ> tiles = QgsVectorTileUtils::tilesInRange( range, zoomLevel );
+  QVector<QgsTileXYZ> tiles = tileMatrixSet.tilesInRange( range, zoomLevel );
 
   // if a tile matrix results in a HUGE number of tile requests, we skip the sort -- it can be expensive
   if ( tiles.size() < 10000 )

src/core/vectortile/qgsvectortileutils.cpp

@@ -163,19 +163,6 @@ struct LessThanTileRequest
   }
 };
 
-QVector<QgsTileXYZ> QgsVectorTileUtils::tilesInRange( QgsTileRange range, int zoomLevel )
-{
-  QVector<QgsTileXYZ> tiles;
-  for ( int tileRow = range.startRow(); tileRow <= range.endRow(); ++tileRow )
-  {
-    for ( int tileColumn = range.startColumn(); tileColumn <= range.endColumn(); ++tileColumn )
-    {
-      tiles.append( QgsTileXYZ( tileColumn, tileRow, zoomLevel ) );
-    }
-  }
-  return tiles;
-}
-
 void QgsVectorTileUtils::sortTilesByDistanceFromCenter( QVector<QgsTileXYZ> &tiles, QPointF center )
 {
   LessThanTileRequest cmp;

src/core/vectortile/qgsvectortileutils.h

@@ -48,8 +48,6 @@ class CORE_EXPORT QgsVectorTileUtils
 {
   public:
 
-    //! Returns a list of tiles in the given tile range
-    static QVector<QgsTileXYZ> tilesInRange( QgsTileRange range, int zoomLevel );
     //! Orders tile requests according to the distance from view center (given in tile matrix coords)
     static void sortTilesByDistanceFromCenter( QVector<QgsTileXYZ> &tiles, QPointF center );
 

tests/src/python/test_qgstiles.py

@@ -94,6 +94,14 @@ def testQgsTileMatrixSet(self):
         self.assertEqual(matrix_set.maximumZoom(), 1)
         self.assertEqual(matrix_set.crs().authid(), 'EPSG:4326')
 
+        range = QgsTileRange(1, 3, 4, 7)
+        tiles = matrix_set.tilesInRange(range, 1)
+        self.assertEqual(len(tiles), 12)
+        self.assertEqual(min(t.column() for t in tiles), 1)
+        self.assertEqual(max(t.column() for t in tiles), 3)
+        self.assertEqual(min(t.row() for t in tiles), 4)
+        self.assertEqual(max(t.row() for t in tiles), 7)
+
         # should not apply any special logic here, and return scales unchanged
         self.assertEqual(matrix_set.calculateTileScaleForMap(1000, QgsCoordinateReferenceSystem('EPSG:4326'),
                                                              QgsRectangle(0, 2, 20, 12), QSize(20, 10), 96), 1000)
@@ -123,6 +131,23 @@ def testQgsTileMatrixSet(self):
         self.assertEqual(matrix_set.tileMatrix(2).zoomLevel(), 2)
         self.assertEqual(matrix_set.tileMatrix(99).zoomLevel(), -1)
 
+        tiles = matrix_set.tilesInRange(QgsTileRange(1, 3, 4, 7), 1)
+        self.assertEqual(len(tiles), 12)
+        self.assertEqual(min(t.column() for t in tiles), 1)
+        self.assertEqual(max(t.column() for t in tiles), 3)
+        self.assertEqual(min(t.row() for t in tiles), 4)
+        self.assertEqual(max(t.row() for t in tiles), 7)
+        self.assertEqual(min(t.zoomLevel() for t in tiles), 1)
+        self.assertEqual(max(t.zoomLevel() for t in tiles), 1)
+        tiles = matrix_set.tilesInRange(QgsTileRange(2, 4, 1, 3), 2)
+        self.assertEqual(len(tiles), 9)
+        self.assertEqual(min(t.column() for t in tiles), 2)
+        self.assertEqual(max(t.column() for t in tiles), 4)
+        self.assertEqual(min(t.row() for t in tiles), 1)
+        self.assertEqual(max(t.row() for t in tiles), 3)
+        self.assertEqual(min(t.zoomLevel() for t in tiles), 2)
+        self.assertEqual(max(t.zoomLevel() for t in tiles), 2)
+
         self.assertAlmostEqual(matrix_set.scaleToZoom(776503144), 1, 5)
         self.assertEqual(matrix_set.scaleToZoom(1776503144), 1)
         self.assertAlmostEqual(matrix_set.scaleToZoom(76503144), 2, 5)