rewrote renderers where necessary for new node structure

Largely conforming renderers to new NodeValue system. Code seems a lot cleaner
this way which is a nice advantage. Likely non-functional as this won't
compile just yet and still needs probably another day or two of testing to get
it back to where it was before.

app/render/backend/audio/audiobackend.cpp

@@ -62,14 +62,14 @@ void AudioBackend::DecompileInternal()
 
 void AudioBackend::ConnectWorkerToThis(RenderWorker *worker)
 {
-  connect(worker, SIGNAL(CompletedCache(NodeDependency)), this, SLOT(ThreadCompletedCache(NodeDependency)));
+  connect(worker, SIGNAL(CompletedCache(NodeDependency, QVariant)), this, SLOT(ThreadCompletedCache(NodeDependency, QVariant)));
 }
 
-void AudioBackend::ThreadCompletedCache(NodeDependency dep)
+void AudioBackend::ThreadCompletedCache(NodeDependency dep, QVariant data)
 {
   caching_ = false;
 
-  QByteArray cached_samples = dep.node()->get_cached_value(dep.range()).toByteArray();
+  QByteArray cached_samples = data.toByteArray();
 
   int offset = params().time_to_bytes(dep.in());
   int length = params().time_to_bytes(dep.range().length());

app/render/backend/audio/audiobackend.h

@@ -30,7 +30,7 @@ protected:
   virtual void ConnectWorkerToThis(RenderWorker* worker) override;
 
 private slots:
-  void ThreadCompletedCache(NodeDependency dep);
+  void ThreadCompletedCache(NodeDependency dep, QVariant data);
 
 private:
   QFile pull_device_;

app/render/backend/audio/audioworker.cpp

@@ -16,8 +16,8 @@ bool AudioWorker::OutputIsAccelerated(NodeOutput *output)
   return false;
 }
 
-QVariant AudioWorker::RunNodeAccelerated(NodeOutput *output)
+NodeValueTable AudioWorker::RunNodeAccelerated(NodeOutput *output)
 {
   Q_UNUSED(output)
-  return QVariant();
+  return NodeValueTable();
 }

app/render/backend/audio/audioworker.h

@@ -13,7 +13,7 @@ protected:
 
   virtual bool OutputIsAccelerated(NodeOutput *output) override;
 
-  virtual QVariant RunNodeAccelerated(NodeOutput *output) override;
+  virtual NodeValueTable RunNodeAccelerated(NodeOutput *output) override;
 
 private: