Input Map

Visera Input Map defines data-driven mappings from physical input (keyboard keys, mouse buttons) to abstract actions. Actions are created and mappings are loaded from .vinputmap JSON; you subscribe to OnTriggered in code.

Asset format

• File extension: .vinputmap
• Schema: Engine/Schemas/InputMap.schema.json

Required fields:

Field	Type	Description
Version	integer (≥1)	Input map format version.
Mappings	array	List of physical input → action mappings.

Each mapping object:

Field	Type	Description
Action	string	Abstract action name (e.g. Jump, Attack).
Source	"KeyboardKey" | "MouseButton"	Physical input source.
Key	string	Required when Source is KeyboardKey. See schema enum for valid keys (e.g. Space, Escape, A).
Button	string	Required when Source is MouseButton. Valid: Left, Right, Middle, Button4–Button8.
Trigger	"Press" | "Release" | "Hold"	When the mapping fires.
Modifiers	array of strings	Optional. Values: Shift, Control, Alt, Super, CapsLock, NumLock. Empty array = none.

How to add a new Action

Step 1: Edit .vinputmap – Add a mapping entry:

{
  "Action": "Attack",
  "Source": "MouseButton",
  "Button": "Left",
  "Trigger": "Press",
  "Modifiers": []
}

Step 2: Load the input map – Call LoadInputMap once (e.g. in game init):

if (!Engine->GetInput()->LoadInputMap(FPath{"Assets/Input/Default.vinputmap"}))
{ LOG_ERROR("Failed to load input map"); }

Step 3: Subscribe in code – Get the action and bind a callback:

auto* AttackAction = Engine->GetInput()->GetAction(FName{"Attack"});
if (AttackAction) AttackAction->OnTriggered.Subscribe([](FInputAction* A) {
    // Handle attack
});

Both steps 2 and 3 are required: the JSON defines the mapping; the code defines the response.

C++ API

• FInput::LoadInputMap(FPath) – Load mappings from .vinputmap. Creates actions as needed. Returns false on error.
• FInput::GetOrAddAction(FName) – Get or create an action.
• FInput::GetAction(FName) – Get action by name. Returns nullptr if not found.
• FInputAction::OnTriggered – TMulticastDelegate<FInputAction*>; subscribe to respond when the action fires.
• ParseInputMap(FJSON) – Parse JSON to TArray<FInputMapping>. Returns NullOpt on parse error.

Valid Key and Button values are listed in Engine/Schemas/InputMap.schema.json for editor autocomplete and validation.