Reduced connection data block size.

Previously we allocated a block for each connection. However when an output is reused by multiple connections this lead to duplicates. It also obfuscated which block is actually being used.

src/AnimGraph/AnimGraphResource.cc

@@ -496,10 +496,12 @@ void AnimGraphResource::CreateBlendTreeInstance(
 
   result.m_name = m_name;
 
+  NodeSocketDataOffsetMap node_offset_map;
+
   CreateBlendTreeRuntimeNodeInstances(result);
-  PrepareBlendTreeIOData(result);
+  PrepareBlendTreeIOData(result, node_offset_map);
   SetRuntimeNodeProperties(result);
-  CreateBlendTreeConnectionInstances(result);
+  CreateBlendTreeConnectionInstances(result, node_offset_map);
 
   result.UpdateOrderedNodes();
   result.ResetNodeStates();
@@ -537,7 +539,8 @@ void AnimGraphResource::CreateBlendTreeRuntimeNodeInstances(
 }
 
 void AnimGraphResource::PrepareBlendTreeIOData(
-    AnimGraphBlendTree& instance) const {
+    AnimGraphBlendTree& instance,
+    NodeSocketDataOffsetMap& node_offset_map) const {
   instance.m_node_descriptor =
       AnimNodeDescriptorFactory("BlendTree", instance.m_nodes[0]);
 
@@ -590,15 +593,23 @@ void AnimGraphResource::PrepareBlendTreeIOData(
     output_block_offset += sizeof(void*);
   }
 
-  // connections: make source and target sockets point to the same address in the connection data storage.
+  //
-  // TODO: instead of every connection, only create data blocks for the source sockets and make sure every source socket gets allocated once.
+  // connecton data storage
+  //
   size_t connection_data_storage_size = 0;
   for (const auto& connection : m_blend_tree_resource.m_connections) {
     const AnimNodeResource* source_node =
         m_blend_tree_resource.m_nodes[connection.source_node_index];
     Socket* source_socket = source_node->m_socket_accessor->GetOutputSocket(
         connection.source_socket_name.c_str());
-    connection_data_storage_size += source_socket->m_type_size;
+
+    NodeSocketPair source_socket_pair{source_node, source_socket->m_name};
+    if (node_offset_map.find(source_socket_pair) == node_offset_map.end()) {
+      node_offset_map.insert(
+          {source_socket_pair, connection_data_storage_size});
+
+      connection_data_storage_size += source_socket->m_type_size;
+    }
   }
 
   if (connection_data_storage_size > 0) {
@@ -608,7 +619,8 @@ void AnimGraphResource::PrepareBlendTreeIOData(
 }
 
 void AnimGraphResource::CreateBlendTreeConnectionInstances(
-    AnimGraphBlendTree& instance) const {
+    AnimGraphBlendTree& instance,
+    NodeSocketDataOffsetMap& node_offset_map) const {
   std::vector<NodeDescriptorBase*> instance_node_descriptors(
       m_blend_tree_resource.m_nodes.size(),
       nullptr);
@@ -630,7 +642,6 @@ void AnimGraphResource::CreateBlendTreeConnectionInstances(
   instance_node_descriptors[1]->m_outputs =
       instance.m_node_descriptor->m_outputs;
 
-  size_t connection_data_offset = 0;
   for (const auto& connection : m_blend_tree_resource.m_connections) {
     NodeDescriptorBase* source_node_descriptor =
         instance_node_descriptors[connection.source_node_index];
@@ -729,32 +740,48 @@ void AnimGraphResource::CreateBlendTreeConnectionInstances(
     instance_connection.m_target_socket_name = target_socket->m_name;
     instance_connection.m_socket = *target_socket;
 
+    size_t socket_data_offset = 0;
+
     if (connection.source_node_index == 1) {
       instance_connection.m_socket = *target_socket;
-    } else if (connection.target_node_index == 0) {
-      instance_connection.m_socket = *source_socket;
     } else {
+      if (connection.target_node_index == 0) {
+        instance_connection.m_socket = *source_socket;
+      }
+
+      NodeSocketPair node_socket_pair{
+          m_blend_tree_resource.m_nodes[connection.source_node_index],
+          source_socket->m_name};
+
+      NodeSocketDataOffsetMap::const_iterator socket_data_offset_iter =
+          node_offset_map.find(node_socket_pair);
+
+      if (socket_data_offset_iter != node_offset_map.end()) {
+        socket_data_offset = socket_data_offset_iter->second;
+      } else {
+        std::cerr << "Error: could not find data offset for node '"
+                  << source_node->m_name << "' and socket '"
+                  << source_socket->m_name << "'." << std::endl;
+        assert(false);
+        abort();
+      }
+
       *target_socket->m_reference.ptr_ptr =
-          &instance.m_connection_data_storage[connection_data_offset];
+          &instance.m_connection_data_storage[socket_data_offset];
       *source_socket->m_reference.ptr_ptr =
-          &instance.m_connection_data_storage[connection_data_offset];
+          &instance.m_connection_data_storage[socket_data_offset];
+
+      if (source_socket->m_type == SocketType::SocketTypeAnimation) {
+        instance.m_animdata_blocks.push_back(
+            (AnimData*)(&instance
+                             .m_connection_data_storage[socket_data_offset]));
+      }
     }
 
     instance.m_node_input_connections[connection.target_node_index].push_back(
         instance_connection);
     instance.m_node_output_connections[connection.source_node_index].push_back(
         instance_connection);
-
-    *instance_connection.m_socket.m_reference.ptr_ptr =
-        &instance.m_connection_data_storage[connection_data_offset];
-
-    if (source_socket->m_type == SocketType::SocketTypeAnimation) {
-      instance.m_animdata_blocks.push_back(
-          (AnimData*)(&instance
-                           .m_connection_data_storage[connection_data_offset]));
-    }
-
-    connection_data_offset += source_socket->m_type_size;
   }
 
   //

src/AnimGraph/AnimGraphResource.h

@@ -161,6 +161,9 @@ struct AnimGraphResource : AnimNodeResource {
   std::string m_graph_type_name;
 
   BlendTreeResource m_blend_tree_resource;
+  typedef std::pair<const AnimNodeResource*, std::string> NodeSocketPair;
+  typedef std::map<NodeSocketPair, int> NodeSocketDataOffsetMap;
+
   StateMachineResource m_state_machine_resource;
 
   void Clear() { m_blend_tree_resource.Reset(); }
@@ -174,8 +177,12 @@ struct AnimGraphResource : AnimNodeResource {
   // BlendTree
   bool SaveBlendTreeResourceToFile(const char* filename) const;
   void CreateBlendTreeRuntimeNodeInstances(AnimGraphBlendTree& result) const;
-  void PrepareBlendTreeIOData(AnimGraphBlendTree& instance) const;
+  void PrepareBlendTreeIOData(
-  void CreateBlendTreeConnectionInstances(AnimGraphBlendTree& instance) const;
+      AnimGraphBlendTree& instance,
+      NodeSocketDataOffsetMap& node_offset_map) const;
+  void CreateBlendTreeConnectionInstances(
+      AnimGraphBlendTree& instance,
+      NodeSocketDataOffsetMap& node_offset_map) const;
   void SetRuntimeNodeProperties(AnimGraphBlendTree& result) const;
 
   bool SaveStateMachineResourceToFile(const char* filename) const;