Method computeHashInternal

Engine/Node.cpp:1506–1602

}

bool
Node::computeHashInternal()
{
    if (!_imp->effect) {
        return false;
    }
    ///Always called in the main thread
    assert( QThread::currentThread() == qApp->thread() );
    if (!_imp->inputsInitialized) {
        qDebug() << "Node::computeHash(): inputs not initialized";
    }

    U64 oldHash, newHash;
    {
        QWriteLocker l(&_imp->knobsAgeMutex);

        oldHash = _imp->hash.value();

        ///reset the hash value
        _imp->hash.reset();

        ///append the effect's own age
        _imp->hash.append(_imp->knobsAge);

        ///append all inputs hash
        boost::shared_ptr<RotoDrawableItem> attachedStroke = _imp->paintStroke.lock();
        NodePtr attachedStrokeContextNode;
        if (attachedStroke) {
            attachedStrokeContextNode = attachedStroke->getContext()->getNode();
        }
        {
            ViewerInstance* isViewer = dynamic_cast<ViewerInstance*>( _imp->effect.get() );

            if (isViewer) {
                int activeInput[2];
                isViewer->getActiveInputs(activeInput[0], activeInput[1]);

                for (int i = 0; i < 2; ++i) {
                    NodePtr input = getInput(activeInput[i]);
                    if (input) {
                        _imp->hash.append( input->getHashValue() );
                    }
                }
            } else {
                for (U32 i = 0; i < _imp->inputs.size(); ++i) {
                    NodePtr input = getInput(i);
                    if (input) {
                        //Since the rotopaint node is connected to the internal nodes of the tree, don't change their hash
                        if ( attachedStroke && (input == attachedStrokeContextNode) ) {
                            continue;
                        }
                        ///Add the index of the input to its hash.
                        ///Explanation: if we didn't add this, just switching inputs would produce a similar
                        ///hash.
                        _imp->hash.append(input->getHashValue() + i);
                    }
                }
            }