some render cache adjustments

app/node/processor/renderer/rendererthreadbase.cpp

@@ -24,7 +24,6 @@
 
 RendererThreadBase::RendererThreadBase(QOpenGLContext *share_ctx, const int &width, const int &height, const olive::PixelFormat &format, const olive::RenderMode &mode) :
   share_ctx_(share_ctx),
-  cancelled_(false),
   width_(width),
   height_(height),
   format_(format),
@@ -34,15 +33,6 @@ RendererThreadBase::RendererThreadBase(QOpenGLContext *share_ctx, const int &wid
   connect(share_ctx_, SIGNAL(aboutToBeDestroyed()), this, SLOT(Cancel()));
 }
 
-void RendererThreadBase::Cancel()
-{
-  // Escape main loop
-  cancelled_ = true;
-
-  // Wait until thread is finished before returning
-  wait();
-}
-
 RenderInstance *RendererThreadBase::render_instance()
 {
   return render_instance_;
@@ -79,11 +69,6 @@ void RendererThreadBase::run()
   mutex_.unlock();
 }
 
-bool RendererThreadBase::Cancelled()
-{
-  return cancelled_;
-}
-
 void RendererThreadBase::StartThread(QThread::Priority priority)
 {
   caller_mutex_.lock();