added clone functions for nodes

Since nodes are are extremely derivative types, we use a clone/copy function
to produce new types of the derived class easily.

app/node/blend/alphaover/alphaover.cpp

@@ -25,6 +25,11 @@ AlphaOverBlend::AlphaOverBlend()
 
 }
 
+Node *AlphaOverBlend::copy()
+{
+  return new AlphaOverBlend();
+}
+
 QString AlphaOverBlend::Name()
 {
   return tr("Alpha Over");

app/node/blend/alphaover/alphaover.h

@@ -28,6 +28,8 @@ class AlphaOverBlend : public BlendNode
 public:
   AlphaOverBlend();
 
+  virtual Node* copy() override;
+
   virtual QString Name() override;
   virtual QString id() override;
   virtual QString Description() override;

app/node/block/block.h

@@ -41,8 +41,6 @@ public:
     kEnd
   };
 
-  virtual Block* copy() = 0;
-
   virtual Type type() = 0;
 
   virtual QString Category() override;

app/node/block/clip/clip.cpp

@@ -27,7 +27,7 @@ ClipBlock::ClipBlock()
   AddParameter(texture_input_);
 }
 
-Block *ClipBlock::copy()
+Node *ClipBlock::copy()
 {
   ClipBlock* c = new ClipBlock();
 

app/node/block/clip/clip.h

@@ -32,7 +32,7 @@ class ClipBlock : public Block
 public:
   ClipBlock();
 
-  virtual Block* copy() override;
+  virtual Node* copy() override;
 
   virtual Type type() override;
 

app/node/block/gap/gap.cpp

@@ -24,7 +24,7 @@ GapBlock::GapBlock()
 {
 }
 
-Block *GapBlock::copy()
+Node *GapBlock::copy()
 {
   GapBlock* c = new GapBlock();
 

app/node/block/gap/gap.h

@@ -32,7 +32,7 @@ class GapBlock : public Block
 public:
   GapBlock();
 
-  virtual Block * copy() override;
+  virtual Node * copy() override;
 
   virtual Type type() override;
 

app/node/color/opacity/opacity.cpp

@@ -37,6 +37,11 @@ OpacityNode::OpacityNode()
   AddParameter(texture_output_);
 }
 
+Node *OpacityNode::copy()
+{
+  return new OpacityNode();
+}
+
 QString OpacityNode::Name()
 {
   return tr("Opacity");

app/node/color/opacity/opacity.h

@@ -29,6 +29,8 @@ class OpacityNode : public Node
 public:
   OpacityNode();
 
+  virtual Node* copy() override;
+
   virtual QString Name() override;
   virtual QString Category() override;
   virtual QString Description() override;

app/node/distort/transform/transform.cpp

@@ -46,6 +46,11 @@ TransformDistort::TransformDistort()
   AddParameter(matrix_output_);
 }
 
+Node *TransformDistort::copy()
+{
+  return new TransformDistort();
+}
+
 QString TransformDistort::Name()
 {
   return tr("Transform");

app/node/distort/transform/transform.h

@@ -29,6 +29,8 @@ class TransformDistort : public Node
 public:
   TransformDistort();
 
+  virtual Node* copy() override;
+
   virtual QString Name() override;
   virtual QString id() override;
   virtual QString Category() override;

app/node/generator/solid/solid.cpp

@@ -31,6 +31,11 @@ SolidGenerator::SolidGenerator() :
   AddParameter(texture_output_);
 }
 
+Node *SolidGenerator::copy()
+{
+  return new SolidGenerator();
+}
+
 QString SolidGenerator::Name()
 {
   return tr("Solid");

app/node/generator/solid/solid.h

@@ -34,6 +34,8 @@ class SolidGenerator : public Node
 public:
   SolidGenerator();
 
+  virtual Node* copy() override;
+
   virtual QString Name() override;
   virtual QString id() override;
   virtual QString Category() override;

app/node/input/media/audio/audio.cpp

@@ -6,6 +6,11 @@ AudioInput::AudioInput()
   AddParameter(samples_output_);
 }
 
+Node *AudioInput::copy()
+{
+  return new AudioInput();
+}
+
 QString AudioInput::Name()
 {
   return tr("Audio Input");

app/node/input/media/audio/audio.h

@@ -8,6 +8,8 @@ class AudioInput : public MediaInput
 public:
   AudioInput();
 
+  virtual Node* copy() override;
+
   virtual QString Name() override;
   virtual QString id() override;
   virtual QString Category() override;

app/node/input/media/video/video.cpp

@@ -18,6 +18,11 @@ VideoInput::VideoInput()
   AddParameter(texture_output_);
 }
 
+Node *VideoInput::copy()
+{
+  return new VideoInput();
+}
+
 QString VideoInput::Name()
 {
   return tr("Video Input");

app/node/input/media/video/video.h

@@ -11,6 +11,8 @@ class VideoInput : public MediaInput
 public:
   VideoInput();
 
+  virtual Node* copy() override;
+
   virtual QString Name() override;
   virtual QString id() override;
   virtual QString Category() override;

app/node/node.h

@@ -50,6 +50,14 @@ class Node : public QObject
 public:
   Node();
 
+  /**
+   * @brief Creates a clone of the Node
+   *
+   * By default, the clone will NOT have the values and connections of the original node. The caller is responsible for
+   * copying that data with functions like CopyInputs() as copies may be done for different reasons.
+   */
+  virtual Node* copy() = 0;
+
   /**
    * @brief Return the name of the node
    *

app/node/output/timeline/timeline.cpp

@@ -53,6 +53,11 @@ TimelineOutput::TimelineOutput()
   AddParameter(length_output_);
 }
 
+Node *TimelineOutput::copy()
+{
+  return new TimelineOutput();
+}
+
 QString TimelineOutput::Name()
 {
   return tr("Timeline");

app/node/output/timeline/timeline.h

@@ -37,6 +37,8 @@ class TimelineOutput : public Node
 public:
   TimelineOutput();
 
+  virtual Node* copy() override;
+
   virtual QString Name() override;
   virtual QString id() override;
   virtual QString Category() override;

app/node/output/viewer/viewer.cpp

@@ -35,6 +35,11 @@ ViewerOutput::ViewerOutput()
   AddParameter(length_input_);
 }
 
+Node *ViewerOutput::copy()
+{
+  return new ViewerOutput();
+}
+
 QString ViewerOutput::Name()
 {
   return tr("Viewer");

app/node/output/viewer/viewer.h

@@ -36,6 +36,8 @@ class ViewerOutput : public Node
 public:
   ViewerOutput();
 
+  virtual Node* copy() override;
+
   virtual QString Name() override;
   virtual QString id() override;
   virtual QString Category() override;

app/widget/timelinewidget/undo/undo.cpp

@@ -25,7 +25,7 @@
 #include <QDebug>
 Block* CreateSplitBlock(Block* block, rational point, QObject* parent = nullptr)
 {
-  Block* copy = block->copy();
+  Block* copy = static_cast<Block*>(block->copy());
   copy->set_length_and_media_in(block->length() - (point - block->in()));
   copy->setParent(parent);