Esempio n. 1
0
void
TileNode::load(osg::NodeVisitor& nv)
{
    // Access the context:
    EngineContext* context = static_cast<EngineContext*>( nv.getUserData() );

    // Create a new load request on demand:
    if ( !_loadRequest.valid() )
    {
        Threading::ScopedMutexLock lock(_mutex);
        if ( !_loadRequest.valid() )
        {
            _loadRequest = new LoadTileData( this, context );
            _loadRequest->setName( _key.str() );
            _loadRequest->setTileKey( _key );
        }
    }

    // Prioritize by LOD. (negated because lower order gets priority)
    float priority = - (float)getTileKey().getLOD();

    if ( context->getOptions().highResolutionFirst() == true )
        priority = -priority;

    // then sort by distance within each LOD.
    float distance = nv.getDistanceToViewPoint( getBound().center(), true );
    priority = 10.0f*priority - log10(distance);

    // testing intermediate loading idea...
    //if ( getTileKey().getLOD() == 5 )
    //    priority += 100.0f;

    // Submit to the loader.
    context->getLoader()->load( _loadRequest.get(), priority, nv );
}
Esempio n. 2
0
void
TileNode::load(osg::NodeVisitor& nv)
{
    // Access the context:
    EngineContext* context = VisitorData::fetch<EngineContext>(nv, ENGINE_CONTEXT_TAG);

    // Create a new load request on demand:
    if ( !_loadRequest.valid() )
    {
        Threading::ScopedMutexLock lock(_mutex);
        if ( !_loadRequest.valid() )
        {
            _loadRequest = new LoadTileData( this, context );
            _loadRequest->setName( _key.str() );
            _loadRequest->setTileKey( _key );
        }
    }

    
    // Construct the load PRIORITY: 0=lowest, 1=highest.
    
    const SelectionInfo& si = context->getSelectionInfo();
    int lod     = getTileKey().getLOD();
    int numLods = si.numLods();
    
    // LOD priority is in the range [0..numLods]
    float lodPriority = (float)lod;
    if ( context->getOptions().highResolutionFirst() == false )
        lodPriority = (float)(numLods - lod);

    float distance = nv.getDistanceToViewPoint(getBound().center(), true);

    // dist priority uis in the range [0..1]
    float distPriority = 1.0 - distance/si.visParameters(0)._visibilityRange;

    // add thenm together, and you get tiles sorted first by lodPriority (because of
    // the biggest range), and second by distance.
    float priority = lodPriority + distPriority;

    // normalize the composite priority to [0..1].
    priority /= (float)(numLods+1);

    // Submit to the loader.
    context->getLoader()->load( _loadRequest.get(), priority, nv );
}
Esempio n. 3
0
void
TileNode::expireChildren(osg::NodeVisitor& nv)
{
    OE_DEBUG << LC << "Expiring children of " << getTileKey().str() << "\n";

    EngineContext* context = static_cast<EngineContext*>( nv.getUserData() );
    if ( !_expireRequest.valid() )
    {
        Threading::ScopedMutexLock lock(_mutex);
        if ( !_expireRequest.valid() )
        {
            _expireRequest = new ExpireTiles(this, context);
            _expireRequest->setName( getTileKey().str() + " expire" );
            _expireRequest->setTileKey( _key );
        }
    }
       
    // Low priority for expiry requests.
    const float lowPriority = -100.0f;
    context->getLoader()->load( _expireRequest.get(), lowPriority, nv );
}