C++ TileSource::createHeightField方法代码示例

osg::HeightField*
ElevationLayer::createHeightFieldFromTileSource(const TileKey&    key,
                                                ProgressCallback* progress)
{
    osg::ref_ptr<osg::HeightField> result;

    if (progress && progress->isCanceled())
    {
        return 0L;
    }

    TileSource* source = getTileSource();
    if ( !source )
    {
        if (progress) progress->message() = "no tile source";
        return 0L;
    }

    // If the key is blacklisted, fail.
    if ( source->getBlacklist()->contains( key ))
    {
        OE_DEBUG << LC << "Tile " << key.str() << " is blacklisted " << std::endl;
        if (progress) progress->message() = "blacklisted";
        return 0L;
    }

    // If the profiles are horizontally equivalent (different vdatums is OK), take the
    // quick route:
    if ( key.getProfile()->isHorizEquivalentTo( getProfile() ) )
    {
        // Only try to get data if the source actually has data
        if (!mayHaveData(key))
        {
            OE_DEBUG << LC << "Source for layer has no data at " << key.str() << std::endl;
            //if (progress) progress->message() = "mayHaveData=false";
            return 0L;
        }

        // Make it from the source:
        result = source->createHeightField( key, getOrCreatePreCacheOp(), progress );

        // If the result is good, we how have a heightfield but it's vertical values
        // are still relative to the tile source's vertical datum. Convert them.
        if (result.valid())
        {
            if ( ! key.getExtent().getSRS()->isVertEquivalentTo( getProfile()->getSRS() ) )
            {
                VerticalDatum::transform(
                    getProfile()->getSRS()->getVerticalDatum(),    // from
                    key.getExtent().getSRS()->getVerticalDatum(),  // to
                    key.getExtent(),
                    result.get() );
            }
        }
        
        // Blacklist the tile if it is the same projection as the source and
        // we can't get it and it wasn't cancelled
        if (!result.valid())
        {
            if ( progress == 0L || !progress->isCanceled() )
            {
                source->getBlacklist()->add( key );
            }
        }
    }

    // Otherwise, profiles don't match so we need to composite:
    else
    {
        // note: this method takes care of the vertical datum shift internally.
        osg::ref_ptr<NormalMap> dummyNormalMap;
        assembleHeightField( key, result, dummyNormalMap, progress );
    }

    if (progress && progress->isCanceled())
    {
        return 0L;
    }

    return result.release();
}

osg::HeightField*
ElevationLayer::createHeightFieldFromTileSource(const TileKey&    key,
                                                ProgressCallback* progress)
{
    osg::HeightField* result = 0L;

    TileSource* source = getTileSource();
    if ( !source )
        return 0L;

    // If the key is blacklisted, fail.
    if ( source->getBlacklist()->contains( key.getTileId() ) )
    {
        OE_DEBUG << LC << "Tile " << key.str() << " is blacklisted " << std::endl;
        return 0L;
    }

    // If the profiles are horizontally equivalent (different vdatums is OK), take the
    // quick route:
    if ( key.getProfile()->isHorizEquivalentTo( getProfile() ) )
    {
        // Only try to get data if the source actually has data
        if ( !source->hasData(key) )
        {
            OE_DEBUG << LC << "Source for layer has no data at " << key.str() << std::endl;
            return 0L;
        }

        // Make it from the source:
        result = source->createHeightField( key, _preCacheOp.get(), progress );

        // If the result is good, we how have a heightfield but it's vertical values
        // are still relative to the tile source's vertical datum. Convert them.
        if ( result )
        {
            if ( ! key.getExtent().getSRS()->isVertEquivalentTo( getProfile()->getSRS() ) )
            {
                VerticalDatum::transform(
                    getProfile()->getSRS()->getVerticalDatum(),    // from
                    key.getExtent().getSRS()->getVerticalDatum(),  // to
                    key.getExtent(),
                    result );
            }
        }
        
        // Blacklist the tile if it is the same projection as the source and we can't get it and it wasn't cancelled
        if ( !result && (!progress || !progress->isCanceled()))
        {
            source->getBlacklist()->add( key.getTileId() );
        }
    }

    // Otherwise, profiles don't match so we need to composite:
    else
    {
        // note: this method takes care of the vertical datum shift internally.
        result = assembleHeightFieldFromTileSource( key, progress );
    }

#if 0
    // If the profiles don't match, use a more complicated technique to assemble the tile:
    if ( !key.getProfile()->isEquivalentTo( getProfile() ) )
    {
        result = assembleHeightFieldFromTileSource( key, progress );
    }
    else
    {
        // Only try to get data if the source actually has data
        if ( !source->hasData( key ) )
        {
            OE_DEBUG << LC << "Source for layer has no data at " << key.str() << std::endl;
            return 0L;
        }

        // Make it from the source:
        result = source->createHeightField( key, _preCacheOp.get(), progress );
    }
#endif



    return result;
}