C++ CacheBin::readImage方法代码示例

GeoImage
ImageLayer::createImageInKeyProfile( const TileKey& key, ProgressCallback* progress, bool forceFallback, bool& out_isFallback )
{
    GeoImage result;

    out_isFallback = false;

    // If the layer is disabled, bail out.
    if ( !getEnabled() )
    {
        return GeoImage::INVALID;
    }

    // Check the max data level, which limits the LOD of available data.
    if ( _runtimeOptions.maxDataLevel().isSet() && key.getLOD() > _runtimeOptions.maxDataLevel().value() )
    {
        return GeoImage::INVALID;
    }

    // Check for a "Minumum level" setting on this layer. If we are before the
    // min level, just return the empty image. Do not cache empties
    if ( _runtimeOptions.minLevel().isSet() && key.getLOD() < _runtimeOptions.minLevel().value() )
    {
        return GeoImage( _emptyImage.get(), key.getExtent() );
    }

    // Check for a "Minimum resolution" setting on the layer. If we are before the
    // min resolution, return the empty image. Do not cache empties.
    if ( _runtimeOptions.minResolution().isSet() )
    {
        double keyres = key.getExtent().width() / getTileSize();
        double keyresInLayerProfile = key.getProfile()->getSRS()->transformUnits(keyres, getProfile()->getSRS());

        if ( keyresInLayerProfile > _runtimeOptions.minResolution().value() )
        {
            return GeoImage( _emptyImage.get(), key.getExtent() );
        }
    }

    OE_DEBUG << LC << "create image for \"" << key.str() << "\", ext= "
        << key.getExtent().toString() << std::endl;


    // locate the cache bin for the target profile for this layer:
    CacheBin* cacheBin = getCacheBin( key.getProfile() );

    // validate that we have either a valid tile source, or we're cache-only.
    if ( ! (getTileSource() || (isCacheOnly() && cacheBin) ) )
    {
        OE_WARN << LC << "Error: layer does not have a valid TileSource, cannot create image " << std::endl;
        _runtimeOptions.enabled() = false;
        return GeoImage::INVALID;
    }

    // validate the existance of a valid layer profile (unless we're in cache-only mode, in which
    // case there is no layer profile)
    if ( !isCacheOnly() && !getProfile() )
    {
        OE_WARN << LC << "Could not establish a valid profile" << std::endl;
        _runtimeOptions.enabled() = false;
        return GeoImage::INVALID;
    }

    // First, attempt to read from the cache. Since the cached data is stored in the
    // map profile, we can try this first.
    if ( cacheBin && getCachePolicy().isCacheReadable() )
    {
        ReadResult r = cacheBin->readImage( key.str(), getCachePolicy().getMinAcceptTime() );
        if ( r.succeeded() )
        {
            ImageUtils::normalizeImage( r.getImage() );
            return GeoImage( r.releaseImage(), key.getExtent() );
        }
        //else if ( r.code() == ReadResult::RESULT_EXPIRED )
        //{
        //    OE_INFO << LC << getName() << " : " << key.str() << " record expired!" << std::endl;
        //}
    }
    
    // The data was not in the cache. If we are cache-only, fail sliently
    if ( isCacheOnly() )
    {
        return GeoImage::INVALID;
    }

    // Get an image from the underlying TileSource.
    result = createImageFromTileSource( key, progress, forceFallback, out_isFallback );

    // Normalize the image if necessary
    if ( result.valid() )
    {
        ImageUtils::normalizeImage( result.getImage() );
    }

    // If we got a result, the cache is valid and we are caching in the map profile, write to the map cache.
    if (result.valid()  &&
        //JB:  Removed the check to not write out fallback data.  If you have a low resolution base dataset (max lod 3) and a high resolution insert (max lod 22)
        //     then the low res data needs to "fallback" from LOD 4 - 22 so you can display the high res inset.  If you don't cache these intermediate tiles then
        //     performance can suffer generating all those fallback tiles, especially if you have to do reprojection or mosaicing.
        //!out_isFallback &&
//.........这里部分代码省略.........

GeoImage
ImageLayer::createImageInKeyProfile(const TileKey&    key, 
                                    ProgressCallback* progress)
{
    if (getStatus().isError())
    {
        return GeoImage::INVALID;
    }

    // If the layer is disabled, bail out.
    if ( !getEnabled() )
    {
        return GeoImage::INVALID;
    }

    // Make sure the request is in range.
    if ( !isKeyInRange(key) )
    {
        return GeoImage::INVALID;
    }


    GeoImage result;

    OE_DEBUG << LC << "create image for \"" << key.str() << "\", ext= "
        << key.getExtent().toString() << std::endl;

    // the cache key combines the Key and the horizontal profile.
    std::string cacheKey = Stringify() << key.str() << "_" << key.getProfile()->getHorizSignature();
    const CachePolicy& policy = getCacheSettings()->cachePolicy().get();
    
    // Check the layer L2 cache first
    if ( _memCache.valid() )
    {
        CacheBin* bin = _memCache->getOrCreateDefaultBin();
        ReadResult result = bin->readObject(cacheKey, 0L);
        if ( result.succeeded() )
            return GeoImage(static_cast<osg::Image*>(result.releaseObject()), key.getExtent());
    }

    // locate the cache bin for the target profile for this layer:
    CacheBin* cacheBin = getCacheBin( key.getProfile() );

    // validate that we have either a valid tile source, or we're cache-only.
    if (getTileSource() || (cacheBin && policy.isCacheOnly()))
    {
        //nop = OK.
    }
    else
    {
        disable("Error: layer does not have a valid TileSource, cannot create image");
        return GeoImage::INVALID;
    }

    // validate the existance of a valid layer profile (unless we're in cache-only mode, in which
    // case there is no layer profile)
    if ( !policy.isCacheOnly() && !getProfile() )
    {
        disable("Could not establish a valid profile");
        return GeoImage::INVALID;
    }

    osg::ref_ptr< osg::Image > cachedImage;

    // First, attempt to read from the cache. Since the cached data is stored in the
    // map profile, we can try this first.
    if ( cacheBin && policy.isCacheReadable() )
    {
        ReadResult r = cacheBin->readImage(cacheKey, 0L);
        if ( r.succeeded() )
        {
            cachedImage = r.releaseImage();
            ImageUtils::fixInternalFormat( cachedImage.get() );            
            bool expired = policy.isExpired(r.lastModifiedTime());
            if (!expired)
            {
                OE_DEBUG << "Got cached image for " << key.str() << std::endl;                
                return GeoImage( cachedImage.get(), key.getExtent() );                        
            }
            else
            {
                OE_DEBUG << "Expired image for " << key.str() << std::endl;                
            }
        }
    }
    
    // The data was not in the cache. If we are cache-only, fail sliently
    if ( policy.isCacheOnly() )
    {
        // If it's cache only and we have an expired but cached image, just return it.
        if (cachedImage.valid())
        {
            return GeoImage( cachedImage.get(), key.getExtent() );            
        }
        else
        {
            return GeoImage::INVALID;
        }
    }

//.........这里部分代码省略.........

GeoImage
ImageLayer::createImageInKeyProfile(const TileKey&    key, 
                                    ProgressCallback* progress)
{
    GeoImage result;

    // If the layer is disabled, bail out.
    if ( !getEnabled() )
    {
        return GeoImage::INVALID;
    }

    // Make sure the request is in range.
    if ( !isKeyInRange(key) )
    {
        return GeoImage::INVALID;
    }

    OE_DEBUG << LC << "create image for \"" << key.str() << "\", ext= "
        << key.getExtent().toString() << std::endl;
    
    // Check the layer L2 cache first
    if ( _memCache.valid() )
    {
        CacheBin* bin = _memCache->getOrCreateBin( key.getProfile()->getFullSignature() );        
        ReadResult result = bin->readObject(key.str(), 0);
        if ( result.succeeded() )
            return GeoImage(static_cast<osg::Image*>(result.releaseObject()), key.getExtent());
        //_memCache->dumpStats(key.getProfile()->getFullSignature());
    }

    // locate the cache bin for the target profile for this layer:
    CacheBin* cacheBin = getCacheBin( key.getProfile() );

    // validate that we have either a valid tile source, or we're cache-only.
    if ( ! (getTileSource() || (isCacheOnly() && cacheBin) ) )
    {
        OE_WARN << LC << "Error: layer does not have a valid TileSource, cannot create image " << std::endl;
        _runtimeOptions.enabled() = false;
        return GeoImage::INVALID;
    }

    // validate the existance of a valid layer profile (unless we're in cache-only mode, in which
    // case there is no layer profile)
    if ( !isCacheOnly() && !getProfile() )
    {
        OE_WARN << LC << "Could not establish a valid profile" << std::endl;
        _runtimeOptions.enabled() = false;
        return GeoImage::INVALID;
    }

    // First, attempt to read from the cache. Since the cached data is stored in the
    // map profile, we can try this first.
    if ( cacheBin && getCachePolicy().isCacheReadable() )
    {
        ReadResult r = cacheBin->readImage( key.str(), getCachePolicy().getMinAcceptTime() );
        if ( r.succeeded() )
        {
            ImageUtils::normalizeImage( r.getImage() );
            return GeoImage( r.releaseImage(), key.getExtent() );
        }
    }
    
    // The data was not in the cache. If we are cache-only, fail sliently
    if ( isCacheOnly() )
    {
        return GeoImage::INVALID;
    }

    // Get an image from the underlying TileSource.
    result = createImageFromTileSource( key, progress );

    // Normalize the image if necessary
    if ( result.valid() )
    {
        ImageUtils::normalizeImage( result.getImage() );
    }

    // memory cache first:
    if ( result.valid() && _memCache.valid() )
    {
        CacheBin* bin = _memCache->getOrCreateBin( key.getProfile()->getFullSignature() ); 
        bin->write(key.str(), result.getImage());
    }

    // If we got a result, the cache is valid and we are caching in the map profile,
    // write to the map cache.
    if (result.valid()  &&
        cacheBin        && 
        getCachePolicy().isCacheWriteable() )
    {
        if ( key.getExtent() != result.getExtent() )
        {
            OE_INFO << LC << "WARNING! mismatched extents." << std::endl;
        }

        cacheBin->write( key.str(), result.getImage() );
    }

    if ( result.valid() )
//.........这里部分代码省略.........