Flow v2.1

This is the upcoming release. This page is updated regularly, after pushing changes to the repository.

This release includes pull requests from the community: 39M (Nil), HomerJohnston (Kyle Wilcox), LindyHopperGT, Ryan DowlingSoka, Soraphis

This is the first release for UE 5.6.

Flow Asset

• Graph refresh refactored. (contributed by HomerJohnston)
  • The goal of this PR is to make the graph editor stop refreshing the entire graph during as many events as possible. It also fixes a few minor bugs related to orphaned pins, running undo/redo commands on edge cases, and unnecessary graph dirtying on edge cases such as when nodes contain orphaned or invalid pins.
  • BREAKING CHANGE. Public void UFlowGraphNode::RefreshContextPins(bool) changed to protected void UFlowGraphNode::RefreshContextPins(). The existing system has some logic that could result in attempts to recursively call ReconstructNode -> RefreshContextPins -> ReconstructNode -> RefreshContextPins. Currently, there are bools to guard against this, but both methods are exposed and this felt unclean to me.
  • UFlowGraphNode::PostLoad now rebuilds the unserialized InputPins and OutputPins arrays using the serialized Pins array.
  • UFlowAsset::HarvestNodeConnections - made this function able to harvest a single node, or harvest the whole graph (pass in nullptr to harvest the whole graph, or pass in a single node to harvest just that node). Then UFlowGraphNode::NodeConnectionListChanged updates node connections for only a single node when its connections are changed.
  • Changed the right-click context menu command, "Refresh Context Pins", to "Reconstruct Node".
  • Modified the following functions to only refresh individual nodes instead of the whole graph by changing NotifyGraphChanged() calls to NotifyNodeChanged(Node): FFlowGraphSchemaAction_NewNode::CreateNode, UFlowGraphSchema::TryCreateConnection, UFlowGraphSchema::BreakNodeLinks, UFlowGraphNode::RemoveOrphanedPin, UFlowGraphNode::AddInstancePin, UFlowGraphNode::RemoveInstancePin.
  • FlowGraphSchemaAction_NewNode::CreateNode now runs ReconstructNode() instead of only spawning default pins.
  • UFlowGraphNode::OnGraphRefresh now runs ReconstructNode() instead of RefreshContextPins(), on all nodes.
  • UFlowGraphNode::RefreshContextPins - no longer runs if an editor transaction is in progress (running undo/redo).
  • `UFlowGraphNode::HavePinsChanged - now disregards any orphaned pin connections.
  • Added a new delegate UFlowGraphNode::OnReconstructNodeCompleted to trigger the rebuild of SFlowGraphNode widgets whenever ReconstructNode is called.
  • SFlowGraphNode added destructor to unbind from UFlowGraphNode delegates.
  • UFlowGraphSchemaadded virtual bool ShouldAlwaysPurgeOnModification() const override { return false; } to reduce unnecessary graph refreshes.
  • UFlowNodeAddOn - GetContextInput/OutputPins functions changed to ignore invalid pins and write a log warning for invalid pins.

Flow Node

• Exposed ability to override node's Category via OverridenNodeCategories list Flow Graph project settings. This way you can fully reorganize Flow Palette to your liking. (inspired by LindyHopperGT's proposal)
• UFlowNode::TriggerOutput won't execute its logic if a given node is deactivated. (contributed by 39M)
• Fixed UFlowNode::Branch never deactivating after checking its condition. (fix suggested by Geckostya)

Flow Component

• Added TriggerRootFlowCustomInput method. (contributed by Soraphis)
• Renamed methods related to Custom Output events, now called BP_OnRootFlowCustomEvent and OnRootFlowCustomEvent.