[Marble-commits] KDE/kdeedu/marble/src/lib

[Jens-Michael Hoffmann]

SVN commit 1118971 by jmhoffmann:

DownloadRegionDialog::region: switch from tile coords to pixel coords.

When calculating tile coords, it is better to do it in pixel coords as long
as possible to not loose accuracy for no reason. With the current approach
of using the top level (of the pyramid) coords as reference this might not
give benefit, but once we switch to bottom level coords, there will be much
better accuracy.

 M  +29 -24    DownloadRegionDialog.cpp  


--- trunk/KDE/kdeedu/marble/src/lib/DownloadRegionDialog.cpp #1118970:1118971
@@ -216,43 +216,48 @@
     int const tileWidth = d->m_textureMapper->tileSize().width();
     int const tileHeight = d->m_textureMapper->tileSize().height();
 
-    int const visibleLevelTileX1 = qMin( westX, eastX ) / tileWidth;
-    int const visibleLevelTileY1 = qMin( northY, southY ) / tileHeight;
-    int const pixelX2 = qMax( westX, eastX );
-    int const pixelY2 = qMax( northY, southY );
-    int const visibleLevelTileX2 = pixelX2 / tileWidth + ( pixelX2 % tileWidth > 0 ? 1 : 0 );
-    int const visibleLevelTileY2 = pixelY2 / tileHeight + ( pixelY2 % tileHeight > 0 ? 1 : 0 );
+    int const visibleLevelX1 = qMin( westX, eastX );
+    int const visibleLevelY1 = qMin( northY, southY );
+    int const visibleLevelX2  = qMax( westX, eastX );
+    int const visibleLevelY2 = qMax( northY, southY );
 
-    mDebug() << "visible level tile coords (x1/y1/x2/y2):"
-             << visibleLevelTileX1 << visibleLevelTileY1 << visibleLevelTileX2 << visibleLevelTileY2;
+    mDebug() << "visible level pixel coords (x1/y1/x2/y2):"
+             << visibleLevelX1 << visibleLevelY1 << visibleLevelX2 << visibleLevelY2;
 
-    QRect topLevelTileCoords;
+    int topLevelX1, topLevelY1, topLevelX2, topLevelY2;
     // the pixel coords calculated above are referring to the originating ("visible") tile level,
     // if the top level is now a different level, we have to take it into account
     if ( d->m_originatingTileLevel > d->m_tileLevelRangeWidget->topLevel() ) {
         int const deltaLevel = d->m_originatingTileLevel - d->m_tileLevelRangeWidget->topLevel();
-        topLevelTileCoords.setCoords( visibleLevelTileX1 >> deltaLevel,
-                                      visibleLevelTileY1 >> deltaLevel,
-                                      visibleLevelTileX2 >> deltaLevel,
-                                      visibleLevelTileY2 >> deltaLevel );
+        topLevelX1 = visibleLevelX1 >> deltaLevel;
+        topLevelY1 = visibleLevelY1 >> deltaLevel;
+        topLevelX2 = visibleLevelX2 >> deltaLevel;
+        topLevelY2 = visibleLevelY2 >> deltaLevel;
     }
     else if ( d->m_originatingTileLevel < d->m_tileLevelRangeWidget->topLevel() ) {
         int const deltaLevel = d->m_tileLevelRangeWidget->topLevel() - d->m_originatingTileLevel;
-        topLevelTileCoords.setCoords( visibleLevelTileX1 << deltaLevel,
-                                      visibleLevelTileY1 << deltaLevel,
-                                      (( visibleLevelTileX2 + 1 ) << deltaLevel ) - 1,
-                                      (( visibleLevelTileY2 + 1 ) << deltaLevel ) - 1 );
+        topLevelX1 = visibleLevelX1 << deltaLevel;
+        topLevelY1 = visibleLevelY1 << deltaLevel;
+        topLevelX2 = visibleLevelX2 << deltaLevel;
+        topLevelY2 = visibleLevelY2 << deltaLevel;
     }
-    else
-        topLevelTileCoords.setCoords( visibleLevelTileX1, visibleLevelTileY1,
-                                      visibleLevelTileX2, visibleLevelTileY2 );
+    else {
+        topLevelX1 = visibleLevelX1;
+        topLevelY1 = visibleLevelY1;
+        topLevelX2 = visibleLevelX2;
+        topLevelY2 = visibleLevelY2;
+    }
+    mDebug() << "top level pixel coords: (x1/y1/x2/y2):"
+             << topLevelX1 << topLevelY1 << topLevelX2 << topLevelY2;
 
-    mDebug() << "originating level tile coords (x1/y1/x2/y2):"
-             << visibleLevelTileX1 << visibleLevelTileY1 << visibleLevelTileX2 << visibleLevelTileY2;
-    mDebug() << "top level tile coords (x1/y1/w x h):" << topLevelTileCoords;
-
     TileCoordsPyramid coordsPyramid( d->m_tileLevelRangeWidget->topLevel(),
                                      d->m_tileLevelRangeWidget->bottomLevel() );
+    QRect topLevelTileCoords;
+    topLevelTileCoords.setCoords( topLevelX1 / tileWidth,
+                                  topLevelY1 / tileHeight,
+                                  topLevelX2 / tileWidth + ( topLevelX2 % tileWidth > 0 ? 1 : 0 ),
+                                  topLevelY2 / tileHeight + ( topLevelY2 % tileHeight > 0 ? 1 : 0 ));
+    mDebug() << "top level tile coords: (x1/y1/size):" << topLevelTileCoords;
     coordsPyramid.setTopLevelCoords( topLevelTileCoords );
     mDebug() << "tiles count:" << coordsPyramid.tilesCount();
     return coordsPyramid;