Fix: assembleTiles could leave gaps of unitializited imagery in a mos…

…aic.
gwaldron · Feb 13, 2015 · 450a575 · 450a575
1 parent 3300e40
commit 450a575
Showing 1 changed file with 48 additions and 3 deletions.
diff --git a/src/osgEarth/ImageLayer.cpp b/src/osgEarth/ImageLayer.cpp
@@ -723,11 +723,11 @@ ImageLayer::assembleImageFromTileSource(const TileKey&    key,
         bool retry = false;
         ImageMosaic mosaic;
 
+        // keep track of failed tiles.
+        std::vector<TileKey> failedKeys;
+
         for( std::vector<TileKey>::iterator k = intersectingKeys.begin(); k != intersectingKeys.end(); ++k )
         {
-            double minX, minY, maxX, maxY;
-            k->getExtent().getBounds(minX, minY, maxX, maxY);
-
             GeoImage image = createImageFromTileSource( *k, progress );
             if ( image.valid() )
             {
@@ -755,6 +755,8 @@ ImageLayer::assembleImageFromTileSource(const TileKey&    key,
             else
             {
                 // the tile source did not return a tile, so make a note of it.
+                failedKeys.push_back( *k );
+
                 if (progress && (progress->isCanceled() || progress->needsRetry()))
                 {
                     retry = true;
@@ -770,6 +772,49 @@ ImageLayer::assembleImageFromTileSource(const TileKey&    key,
             return GeoImage::INVALID;
         }
 
+        // We got at least one good tile, so go through the bad ones and try to fall back on
+        // lower resolution data to fill in the gaps. The entire mosaic must be populated or
+        // this qualifies as a bad tile.
+        for(std::vector<TileKey>::iterator k = failedKeys.begin(); k != failedKeys.end(); ++k)
+        {
+            GeoImage image;
+
+            for(TileKey parentKey = k->createParentKey();
+                parentKey.valid() && !image.valid();
+                parentKey = parentKey.createParentKey())
+            {
+                image = createImageFromTileSource( parentKey, progress );
+                if ( image.valid() )
+                {
+                    ImageUtils::normalizeImage(image.getImage());
+                    if (   (image.getImage()->getDataType() != GL_UNSIGNED_BYTE)
+                        || (image.getImage()->getPixelFormat() != GL_RGBA) )
+                    {
+                        osg::ref_ptr<osg::Image> convertedImg = ImageUtils::convertToRGBA8(image.getImage());
+                        if (convertedImg.valid())
+                        {
+                            image = GeoImage(convertedImg, image.getExtent());
+                        }
+                    }
+
+                    OE_DEBUG << LC << "Tile " << k->str() << " fell back on " << parentKey.str() << "\n";
+
+                    // cut out the piece we need:
+                    GeoImage croppedImage = image.crop( k->getExtent(), true, image.getImage()->s(), image.getImage()->t() );
+
+                    // and queue it.
+                    mosaic.getImages().push_back( TileImage(croppedImage.getImage(), *k) );
+                }
+            }
+
+            if ( !image.valid() )
+            {
+                // a tile completely failed, even with fallback. Eject.
+                OE_DEBUG << LC << "Couldn't fallback on tiles for ImageMosaic" << std::endl;
+                return GeoImage::INVALID;
+            }
+        }
+
         // all set. Mosaic all the images together.
         double rxmin, rymin, rxmax, rymax;
         mosaic.getExtents( rxmin, rymin, rxmax, rymax );