K2Nodes Intro¶
The Mountea Dialogue System ships one custom Blueprint graph node, K2Node_MounteaDialogueCallFunction. This page explains what it is, why it exists, and how to read the colors it puts on your graph - there's nothing you need to set up, but it helps to know what you're looking at.
1. What a K2Node Is¶
A K2Node is a custom Blueprint graph node implemented through the Blueprint compiler itself, rather than the plain "call this function" node the engine generates automatically for every BlueprintCallable function - it can change how a node looks, but that's the only thing this particular one does.
2. Why This Plugin Has One¶
A large Blueprint graph can end up with hundreds of grey function-call nodes, and nothing about a stock node's appearance tells you it came from the Dialogue System rather than the engine, another plugin, or your own game code.
Why a Custom Node Instead of Just More Functions?
The plugin doesn't need a custom node to expose its functions to Blueprint - plain BlueprintCallable already does that. The custom node exists purely so those functions are easy to spot once they're on the graph: color-coded by role and branded as coming from the Dialogue System, instead of blending into the grey.
3. How You Encounter It¶
You don't do anything to opt in. Any function in the plugin's three modules (MounteaDialogueSystem, MounteaDialogueSystemEditor, MounteaDialogueSystemDeveloper) that carries a recognized CustomTag metadata value is automatically registered with this node instead of the engine's default one - the grey call-function node for that function never appears in the right-click menu at all.
Info
The scan covers Blueprint Function Libraries, interfaces, and ordinary classes alike, so the same styling shows up whether you're calling a static helper, an interface function, or a method on a component like MounteaDialogueManager or MounteaDialogueParticipant.
4. The Three Roles¶
The CustomTag value on a function decides which role the node takes on, which in turn drives its title color, its icon, and the extra line added to its tooltip:
| Role | CustomTag Value |
Node Title Color | What It Signals |
|---|---|---|---|
| Getter | MounteaK2Getter |
Dark navy blue | Reads and returns a value without changing anything |
| Setter | MounteaK2Setter |
Deep plum/magenta | Writes or modifies a value or state on the target |
| Validator | MounteaK2Validate |
Amber/bronze | Checks data against rules and reports whether it's valid |
Each role also gets its own small icon (distinct per role, rendered next to the node title) and, if the engine doesn't already show one, a Mountea logo watermark in the node's corner. Underneath the title, the node adds a context line reading "Source is Mountea Dialogue System" (or the specific class the function lives on, e.g. "Source is Mountea Dialogue System Settings") - a second, textual confirmation that you're not looking at a stock engine node.
Warning
This is styling and discoverability only, not a different kind of node. It doesn't reshape pins, resolve wildcards, or change execution in any way - calling one of these functions from Blueprint behaves exactly like calling any other BlueprintCallable function. The only difference is what the node looks like on your graph.
5. Blueprint vs C++¶
This entire feature lives in the Blueprint graph compiler and has no C++ call-site equivalent. A C++ caller just calls the underlying function directly and never sees this node at all - nothing about the function's behavior, signature, or return value changes because of it.