Frequently Asked Questions¶

General¶

Does FWDialogueSystem require any other plugins?¶

No. FWDialogueSystem has no external dependencies. The built-in conditions and actions reference game concepts (items, quests, skills, currency) through their own evaluation/execution methods, which you implement to integrate with your game's systems.

Can I use this plugin for non-NPC dialogue (e.g., intercom messages, environmental storytelling)?¶

Yes. The dialogue component does not assume anything about the owning Actor. Attach it to any Actor -- an NPC, a radio, a terminal, a sign. The SpeakerName field in each node can be set to anything.

Does this plugin support Blueprint-only projects?¶

No. FWDialogueSystem contains C++ modules and requires a C++ project.

Can I create conditions and actions in Blueprints?¶

Yes. Both UFWDialogueConditionBase and UFWDialogueActionBase can be subclassed in Blueprints. Override the Evaluate or Execute function respectively.

Dialogue Trees¶

How do I make the NPC say different things based on quest progress?¶

You have two approaches:

Approach A -- Single tree with conditional responses. Create one dialogue tree with a greeting node that has multiple responses, each gated by a FWDlgCondition_QuestState condition. The player only sees responses whose conditions pass. See the tutorial for a complete example.

Approach B -- Multiple trees. Create separate dialogue trees for each quest state and select which tree to pass to StartDialogue based on external logic. This is simpler for NPCs with dramatically different conversations per state.

What happens if no responses pass their conditions?¶

If all responses on a node have conditions and none of them pass, GetAvailableResponses returns an empty array. Your UI should handle this case -- typically by showing a "Continue" or "End Conversation" button that calls EndDialogue.

Always Include an Unconditional Response

As a best practice, include at least one response with no conditions on every node (such as "Farewell" or "Continue"). This ensures the player always has a way to exit or advance the conversation.

Can a response loop back to an earlier node?¶

Yes. Set NextNodeId to any valid node ID in the tree, including nodes that appeared earlier in the conversation. This allows for:

Returning to a main menu node after a sub-topic
Repeating a node until the player makes a different choice
Creating conversational loops

Infinite Loops

There is no built-in loop detection. If you create a cycle with no exit path (e.g., Node A leads to Node B which leads back to Node A, with no farewell option), the player will be stuck in the dialogue. Always provide an exit.

Can I have multiple dialogue trees reference the same nodes?¶

No. Each UFWDialogueTree is a self-contained asset. Nodes are local to their tree and cannot be shared across trees. If you need shared dialogue segments, duplicate the nodes or create a shared subtree that multiple NPCs reference by using the same dialogue tree asset.

What is the maximum number of nodes per tree?¶

There is no hard limit. Node lookup by ID uses a linear search through the array, so extremely large trees (hundreds of nodes) may have a minor lookup cost. For practical purposes, trees with up to 50-100 nodes perform without issue.

Conditions¶

How are multiple conditions on a single response evaluated?¶

With AND logic. All conditions must return true for the response to appear. If any condition returns false, the entire response is hidden.

How do I implement OR logic for conditions?¶

Create separate responses that lead to the same NextNodeId. Each response has its own condition set. If either response's conditions pass, the player sees that path.

Response A: "I can pay in gold" (Condition: HasCurrency Gold >= 100) --> Node 5
Response B: "I can pay in gems" (Condition: HasItem Gems >= 3)      --> Node 5

Can conditions modify game state?¶

No. The Evaluate method is const and should be side-effect-free. Use actions for state changes, not conditions.

When are conditions evaluated?¶

Conditions are evaluated when GetAvailableResponses is called. This happens automatically when OnNodeChanged fires, and can be called again manually if you need to re-evaluate (e.g., if game state changed while the dialogue UI was open).

Actions¶

What happens if an action fails (e.g., inventory full)?¶

The dialogue still advances. Actions are fire-and-forget. If you need to validate before executing, add a corresponding condition to the response. For example, pair FWDlgAction_GiveItem with a custom condition that checks for available inventory space.

Can I chain multiple actions on a single response?¶

Yes. Add multiple actions to a response's Actions array. They execute in array order, top to bottom.

What is the difference between EntryActions and Response Actions?¶

EntryActions fire when a node becomes the active node (i.e., it is now being displayed to the player). Use these for side effects that should happen regardless of which response the player picks.
Response Actions fire when the player selects a specific response. Use these for effects tied to the player's choice.

Can actions trigger dialogue events (e.g., start a new dialogue)?¶

Actions can call any game code, including starting a new dialogue. However, be careful about calling StartDialogue from within an action -- the current dialogue is still active at that point. The component will end the current dialogue first, which may cause unexpected event ordering.

UI Integration¶

How do I animate dialogue text (typewriter effect)?¶

The component provides the full text in FFWDialogueNode::DialogueText. Implement the typewriter effect in your UI widget by revealing characters over time. See the Blueprints page for a pattern.

Can I show speaker portraits?¶

The component provides SpeakerName as an FText. Map speaker names to portrait textures using a Data Table or a custom lookup function in your UI widget. The dialogue system itself does not manage portrait assets.

How do I handle voice-over audio?¶

FWDialogueSystem does not include audio playback. Trigger audio from your UI or NPC Blueprint when OnNodeChanged fires. You can map NodeId values to audio assets using a Data Table or a custom mapping.

Networking¶

Is dialogue replicated across the network?¶

The dialogue component itself does not replicate. Dialogue is typically a client-side interaction between one player and one NPC. If you need other players to see that an NPC is "in conversation" (e.g., to prevent simultaneous interactions), implement a simple replicated busy flag on the NPC Actor.

Can actions trigger server-side logic?¶

If your action subclass calls a server RPC, yes. The built-in actions execute locally. For server-authoritative games, create custom action subclasses that call your game's server functions.

Performance¶

Is there a performance cost to evaluating conditions?¶

Condition evaluation calls a virtual function per condition per response. For typical dialogue nodes (5-10 responses, 1-3 conditions each), the cost is negligible. Avoid placing expensive game queries (database lookups, pathfinding) inside condition evaluation.

Are dialogue trees loaded into memory all at once?¶

Yes, when the tree asset is loaded. However, dialogue trees are small -- they contain only text and references to condition/action objects, not textures or meshes. A tree with 50 nodes is a few kilobytes at most.

Troubleshooting¶

The NPC starts talking but the UI does not appear.¶

Verify that you have bound to OnDialogueStarted and OnNodeChanged events. The component does not manage UI -- it only fires events. Your UI code must respond to those events.

A response that should appear is missing.¶

Check its conditions. Call GetAvailableResponses in a debug context and log the result count. Then check each condition individually:

Is the condition class correct?
Are the condition properties (ItemId, QuestId, etc.) spelled exactly right?
Does the condition's Evaluate function return true for the current game state?

SelectResponse does nothing or crashes.¶

Verify the index you are passing matches the GetAvailableResponses array, not the raw Responses array from GetCurrentNode. These arrays may differ if conditions filter some responses out.

EntryActions fire twice.¶

This can happen if StartDialogue is called twice in rapid succession (e.g., double-click on interact). Guard your interaction logic with an IsDialogueActive check before calling StartDialogue.