One fix for bug [#33785] compositor is (unnecessarily?) slow

Added additional buffers - new subtree - for groupnodes.
One needs to be aware of how groupnodes should be created. 
Having translate & scale nodes, with the translate inside the groupnode and the scale node outside, causes artefacts.
Both should be inside or outside the groupnode. Same holds for other distort nodes. 
  

3 files changed, 23 insertions, 7 deletions

diff --git a/source/blender/compositor/nodes/COM_GroupNode.cpp b/source/blender/compositor/nodes/COM_GroupNode.cpp
index e10d7dbad2e..32190010aa6 100644
--- a/source/blender/compositor/nodes/COM_GroupNode.cpp
+++ b/source/blender/compositor/nodes/COM_GroupNode.cpp
@@ -58,7 +58,7 @@ void GroupNode::ungroup(ExecutionSystem &system)
 		InputSocket *inputSocket = inputsockets[index];
 		bNodeSocket *editorInput = inputSocket->getbNodeSocket();
 		if (editorInput->groupsock) {
-			SocketProxyNode *proxy = new SocketProxyNode(bnode, editorInput, editorInput->groupsock);
+            SocketProxyNode *proxy = new SocketProxyNode(bnode, editorInput, editorInput->groupsock, false);
 			inputSocket->relinkConnections(proxy->getInputSocket(0), index, &system);
 			ExecutionSystemHelper::addNode(system.getNodes(), proxy);
 		}
@@ -68,7 +68,7 @@ void GroupNode::ungroup(ExecutionSystem &system)
 		OutputSocket *outputSocket = outputsockets[index];
 		bNodeSocket *editorOutput = outputSocket->getbNodeSocket();
 		if (editorOutput->groupsock) {
-			SocketProxyNode *proxy = new SocketProxyNode(bnode, editorOutput->groupsock, editorOutput);
+            SocketProxyNode *proxy = new SocketProxyNode(bnode, editorOutput->groupsock, editorOutput, true);
 			outputSocket->relinkConnections(proxy->getOutputSocket(0));
 			ExecutionSystemHelper::addNode(system.getNodes(), proxy);
 		}
diff --git a/source/blender/compositor/nodes/COM_SocketProxyNode.cpp b/source/blender/compositor/nodes/COM_SocketProxyNode.cpp
index bfb32a96156..e6026675d20 100644
--- a/source/blender/compositor/nodes/COM_SocketProxyNode.cpp
+++ b/source/blender/compositor/nodes/COM_SocketProxyNode.cpp
@@ -27,11 +27,14 @@
 #include "COM_SetValueOperation.h"
 #include "COM_SetVectorOperation.h"
 #include "COM_SetColorOperation.h"
+#include "COM_WriteBufferOperation.h"
+#include "COM_ReadBufferOperation.h"
 
-SocketProxyNode::SocketProxyNode(bNode *editorNode, bNodeSocket *editorInput, bNodeSocket *editorOutput) : Node(editorNode, false)
+SocketProxyNode::SocketProxyNode(bNode *editorNode, bNodeSocket *editorInput, bNodeSocket *editorOutput, bool buffer) : Node(editorNode, false)
 {
 	DataType dt;
-	
+    this->m_buffer = buffer;
+
 	dt = COM_DT_VALUE;
 	if (editorInput->type == SOCK_RGBA) dt = COM_DT_COLOR;
 	if (editorInput->type == SOCK_VECTOR) dt = COM_DT_VECTOR;
@@ -49,11 +52,22 @@ void SocketProxyNode::convertToOperations(ExecutionSystem *graph, CompositorCont
 	InputSocket *inputsocket = this->getInputSocket(0);
 	if (outputsocket->isConnected()) {
 		if (inputsocket->isConnected()) {
-			SocketProxyOperation *operation = new SocketProxyOperation(this->getOutputSocket()->getDataType());
+            SocketProxyOperation *operation = new SocketProxyOperation(this->getOutputSocket()->getDataType());
 			inputsocket->relinkConnections(operation->getInputSocket(0));
 			outputsocket->relinkConnections(operation->getOutputSocket(0));
 			graph->addOperation(operation);
-		}
+            if (m_buffer){
+                WriteBufferOperation * writeOperation = new WriteBufferOperation();
+                ReadBufferOperation * readOperation = new ReadBufferOperation();
+                readOperation->setMemoryProxy(writeOperation->getMemoryProxy());
+
+                operation->getOutputSocket()->relinkConnections(readOperation->getOutputSocket());
+                addLink(graph, operation->getOutputSocket(), writeOperation->getInputSocket(0));
+
+                graph->addOperation(writeOperation);
+                graph->addOperation(readOperation);
+            }
+        }
 		else {
 			/* If input is not connected, add a constant value operation instead */
 			switch (outputsocket->getDataType()) {
diff --git a/source/blender/compositor/nodes/COM_SocketProxyNode.h b/source/blender/compositor/nodes/COM_SocketProxyNode.h
index ea50be418e2..a83ac094b2b 100644
--- a/source/blender/compositor/nodes/COM_SocketProxyNode.h
+++ b/source/blender/compositor/nodes/COM_SocketProxyNode.h
@@ -30,8 +30,10 @@
  * @ingroup Node
  */
 class SocketProxyNode : public Node {
+private:
+    bool m_buffer;
 public:
-	SocketProxyNode(bNode *editorNode, bNodeSocket *editorInput, bNodeSocket *editorOutput);
+    SocketProxyNode(bNode *editorNode, bNodeSocket *editorInput, bNodeSocket *editorOutput, bool buffer);
 	void convertToOperations(ExecutionSystem *graph, CompositorContext *context);
 
 	virtual bool isProxyNode() const { return true; }