sweeping node graph changes for new rendering pipeline

The new rendering pipeline strives to simplify the nodes themselves as much
as possible and move much of the logic to an external rendering engine. This
change removes all of the responsibilities that no longer belong to the
nodes themselves and will soon be folded into the renderer.

app/node/node.h

@@ -129,13 +129,6 @@ public:
    */
   virtual QString Code(NodeOutput* output);
 
-  /**
-   * @brief Wrapper for Process()
-   *
-   * It's recommended to call this directly over Value(), yet in derivatives of Node, override Value().
-   */
-  QVariant Run(NodeOutput* output, const rational &in, const rational &out);
-
   /**
    * @brief For nodes that have different dependencies at different times, this function can be used for that purpose
    *
@@ -176,7 +169,7 @@ public:
   /**
    * @brief Add's unique information about this Node at the given time to a QCryptographicHash
    */
-  virtual void Hash(QCryptographicHash* hash, NodeOutput *from, const rational& time);
+  //virtual void Hash(QCryptographicHash* hash, NodeOutput *from, const rational& time);
 
   /**
    * @brief Convert a pointer to a value that can be sent between NodeParams
@@ -200,15 +193,19 @@ public:
    */
   virtual void InvalidateCache(const rational& start_range, const rational& end_range, NodeInput* from = nullptr);
 
-  /**
-   * @brief Lock mutex (for thread safety)
-   */
-  void Lock();
+  virtual TimeRange InputTimeAdjustment(NodeInput* input, const TimeRange& input_time);
 
   /**
-   * @brief Unock mutex (for thread safety)
+   * @brief User input lock prevents any user changes while a graph is being rendered
    */
-  void Unlock();
+  void LockUserInput();
+  void UnlockUserInput();
+
+  /**
+   * @brief Processing lock prevents more than one thread trying to process a Node at once
+   */
+  void LockProcessing();
+  void UnlockProcessing();
 
   /**
    * @brief Copies inputs from from Node to another including connections
@@ -235,6 +232,21 @@ public:
    */
   virtual bool IsBlock();
 
+  /**
+   * @brief The main processing function
+   *
+   * The node's main purpose is to take values from inputs to set values in outputs. For whatever subclass node you
+   * create, this is where the code for that goes.
+   *
+   * Note that as a video editor, the node graph has to work across time. Depending on the purpose of your node, it may
+   * output different values depending on the time, and even if not, it will likely be receiving different input
+   * depending on the time. Most of the difficult work here is handled by NodeInput::get_value() which you should pass
+   * the `time` parameter to. It will return its value (at that time, if it's keyframed), or pass the time to a
+   * corresponding output if it's connected to one. If your node doesn't directly deal with time, the default behavior
+   * of the NodeParam objects will handle everything related to it automatically.
+   */
+  virtual QVariant Value(NodeOutput* output);
+
 protected:
   /**
    * @brief Add a parameter to this node
@@ -252,21 +264,6 @@ protected:
    */
   void RemoveParameter(NodeParam* param);
 
-  /**
-   * @brief The main processing function
-   *
-   * The node's main purpose is to take values from inputs to set values in outputs. For whatever subclass node you
-   * create, this is where the code for that goes.
-   *
-   * Note that as a video editor, the node graph has to work across time. Depending on the purpose of your node, it may
-   * output different values depending on the time, and even if not, it will likely be receiving different input
-   * depending on the time. Most of the difficult work here is handled by NodeInput::get_value() which you should pass
-   * the `time` parameter to. It will return its value (at that time, if it's keyframed), or pass the time to a
-   * corresponding output if it's connected to one. If your node doesn't directly deal with time, the default behavior
-   * of the NodeParam objects will handle everything related to it automatically.
-   */
-  virtual QVariant Value(NodeOutput* output, const rational &in, const rational &out);
-
   /**
    * @brief Retrieve the last timecode Process() was called with
    */
@@ -325,12 +322,12 @@ private:
   /**
    * @brief Used for thread safety from main thread
    */
-  QMutex lock_;
+  QMutex user_input_lock_;
 
   /**
    * @brief Used for thread safety between multiple threads
    */
-  QMutex run_lock_;
+  QMutex processing_lock_;
 
   /**
    * @brief Internal variable for whether this Node can be deleted or not