A container for actions that make sense within a given context. More...

#include <input_system.hpp>

Public Member Functions
	ActionContext (InputManager &inputManager, const ContextName &name)
	Construct a new action context.

	ActionContext (InputManager &&inputManager, const ContextName &name)=delete
	Construct a new action context.

::std::vector<::std::pair< ActionDefinition, ActionData > >	getTriggeredActions ()
	Returns a list of triggered actions following input mapping in this context.

void	registerAction (const ActionName &name, InputAttributesType attributes)
	Creates an action and specifies its attributes.

void	registerAction (const nlohmann::json &actionParameters)
	Creates an action and specifies its attributes based on its JSON description.

void	unregisterAction (const ActionName &name)
	Removes an action from this context.

void	registerInputBind (const ActionName &forAction, AxisFilter targetAxis, const InputCombo &withInput)
	Register a binding from an input-sign-axis-modifiers combination to a specific axis of an action.

void	registerInputBind (const nlohmann::json &inputBindParameters)
	Register a binding from an input-sign-axis-modifiers combination to a specific axis of an action.

void	unregisterInputBind (const InputCombo &inputCombo)
	Remove the binding from this input-sign-axis-modifier combination to whatever action it's bound to.

void	unregisterInputBinds (const ActionName &forAction)
	Removes all input binds associated with a particular action.

void	unregisterInputBinds ()
	Removes all input combo -> action-axis bindings.

bool	propagateAllowed ()
	Checks whether this context allows propagation to lower priority contexts.

void	setPropagateAllowed (bool allowPropagate)
	Enables or disables input propagation to lower priority contexts.

bool	enabled ()
	Checks whether this context is active and able to process input events.

void	setEnabled (bool enable)
	Enable or disable this context, allowing it to or preventing it from receiving input events.

Static Public Member Functions
static ActionData	ApplyInput (const ActionDefinition &actionDefinition, const ActionData &actionData, const AxisFilter targetAxis, const UnmappedInputValue &inputValue)
	Returns the result of applying an unmapped input combo value to its target action-axis.

Private Member Functions
void	resetActionData (const ActionName &forAction, uint32_t timestamp)
	Sets action data for this action to 0.f or false, and queues a corresponding RESET action.

void	resetActionData (uint32_t timestamp)
	Sets all action data to 0.f or false for ALL actions, and queues related RESET actions.

void	mapToAction (const UnmappedInputValue &inputValue, const InputCombo &inputCombo)
	Maps the given input value to its assigned action state.

Private Attributes
InputManager &	mInputManager

const ContextName	mName
	The name of this action context.

bool	mEnabled { true }
	Determines whether this action context is active and allowed to process any bound input events.

bool	mPropagateInput { false }
	Determines whether, after mapping an input event to its corresponding action, other contexts waiting for the input event are allowed to have a go at processing it also.

::std::unordered_map< ActionDefinition, ActionData >	mActions {}
	All actions defined for this context and their most recently triggered state.

::std::vector<::std::pair< ActionDefinition, ActionData > >	mPendingTriggeredActions {}
	Action state changes that have recently been triggered, in the order that they were triggered.

::std::unordered_map< ActionDefinition, ::std::set< InputCombo > >	mActionToInputBinds {}
	All input bindings associated with a specific action.

::std::unordered_map< InputCombo, ::std::pair< AxisFilter, ActionDefinition > >	mInputBindToAction {}
	Mapping from unmapped input controls, provided by the input manager, to their associated action definitions.

Friends
class	InputManager

Detailed Description

A container for actions that make sense within a given context.

Different contexts might have different requirements, even with the same set of inputs. For example, it might make sense to have a "slash" action in the game world, but in the context of a game menu, slash cannot have meaning.

Action Contexts turn those requirements into a container object, where the semantics of an input event are indicated by the action and context, and are one degree removed from the inputs themselves.

This can be useful, for example, when a game requires input for character movement across multiple platforms. For a console, or when a controller is present, it would make sense to query the value of the left analog stick. However, no such control exists on a keyboard, which is the most common input device for a PC.

Action Contexts, among other things, allow it so that multiple mappings to the same type of input are possible, and the handlers of the input don't have to reason about differences in platforms. In the example above, that mapping might look something like this:

  W    ______
A|S|D        \___.--> Character : Move (2 Axes) --> (Move handlers)
<keyboard>    /
             /
            /
(( L ))----/
<controller>

This allows developers to reason about input somewhat uniformly during game development. The input mappings themselves are a matter of wiring inputs to high level actions during configuration, separate from game logic.

In this case, all a game programmer need know is that they want signed non-location state input on 2 axes, and that they want it for "Move".

Constructor & Destructor Documentation

◆ ActionContext() [1/2]

ToyMaker::ActionContext::ActionContext	(	InputManager &	inputManager,
		const ContextName &	name )

inline

Construct a new action context.

Parameters

inputManager	The input manager in charge of this context.
name	The name of the context.

◆ ActionContext() [2/2]

ToyMaker::ActionContext::ActionContext	(	InputManager &&	inputManager,
		const ContextName &	name )

delete

Construct a new action context.

Parameters

inputManager	The input manager in charge of this context.
name	The name of the context.

Member Function Documentation

◆ ApplyInput()

ActionData ActionContext::ApplyInput	(	const ActionDefinition &	actionDefinition,
		const ActionData &	actionData,
		const AxisFilter	targetAxis,
		const UnmappedInputValue &	inputValue )

static

Returns the result of applying an unmapped input combo value to its target action-axis.

Parameters

actionDefinition	Action definition of target action (but usually just a context-action name string pair).
actionData	The previous value of the data associated with the action.
targetAxis	The axis of the action affected.
inputValue	The value associated with the input combo being applied.

Returns: ActionData The action data after the input has been applied.

See also: InputCombo

◆ getTriggeredActions()

std::vector< std::pair< ActionDefinition, ActionData > > ActionContext::getTriggeredActions ( )

Returns a list of triggered actions following input mapping in this context.

Returns: std::vector<::std::pair<ActionDefinition, ActionData>> List of triggered actions after inputs are applied.

◆ mapToAction()

void ActionContext::mapToAction	(	const UnmappedInputValue &	inputValue,
		const InputCombo &	inputCombo )

private

Maps the given input value to its assigned action state.

Parameters

inputValue	The value of the input combo to be mapped to an axis of an action belonging to this action's context.
inputCombo	The combo whose value is being mapped.

◆ propagateAllowed()

bool ToyMaker::ActionContext::propagateAllowed ( )

inline

Checks whether this context allows propagation to lower priority contexts.

Return values

true	Allows propagation to lower priority contexts;
false	Disallows propagation to lower priority contexts;

◆ registerAction() [1/2]

void ActionContext::registerAction	(	const ActionName &	name,
		InputAttributesType	attributes )

Creates an action and specifies its attributes.

Parameters

name	The name of the action.
attributes	The attributes of the action (no. of axes, state or change, etc.)

◆ registerAction() [2/2]

void ActionContext::registerAction ( const nlohmann::json & actionParameters )

Creates an action and specifies its attributes based on its JSON description.

Parameters

actionParameters The action's description in JSON.

See also: InputManager::registerAction()

◆ registerInputBind() [1/2]

void ActionContext::registerInputBind	(	const ActionName &	forAction,
		AxisFilter	targetAxis,
		const InputCombo &	withInput )

Register a binding from an input-sign-axis-modifiers combination to a specific axis of an action.

Parameters

forAction	The action being mapped to.
targetAxis	The axis of the action affected.
withInput	The combo responsible for changing the action's value.

See also: InputManager::registerInputBind()

◆ registerInputBind() [2/2]

void ActionContext::registerInputBind ( const nlohmann::json & inputBindParameters )

Register a binding from an input-sign-axis-modifiers combination to a specific axis of an action.

Parameters

inputBindParameters A JSON description of the input bind.

◆ resetActionData() [1/2]

void ActionContext::resetActionData	(	const ActionName &	forAction,
		uint32_t	timestamp )

private

Sets action data for this action to 0.f or false, and queues a corresponding RESET action.

Parameters

forAction	The action whose vlaue is being reset.
timestamp	The time of the reset, in milliseconds since application start.

◆ resetActionData() [2/2]

void ActionContext::resetActionData ( uint32_t timestamp )

private

Sets all action data to 0.f or false for ALL actions, and queues related RESET actions.

Parameters

timestamp The time of the reset, in milliseconds since application start.

◆ setPropagateAllowed()

void ToyMaker::ActionContext::setPropagateAllowed ( bool allowPropagate )

inline

Enables or disables input propagation to lower priority contexts.

Parameters

allowPropagate Whether propagation is permitted (for handled actions)

◆ unregisterAction()

void ActionContext::unregisterAction ( const ActionName & name )

Removes an action from this context.

Parameters

name	The name of the action being removed.

◆ unregisterInputBind()

void ActionContext::unregisterInputBind ( const InputCombo & inputCombo )

Remove the binding from this input-sign-axis-modifier combination to whatever action it's bound to.

Parameters

inputCombo The combo of the input bind being removed.

◆ unregisterInputBinds()

void ActionContext::unregisterInputBinds ( const ActionName & forAction )

Removes all input binds associated with a particular action.

Parameters

forAction The action whose input binds are being removed.

The documentation for this class was generated from the following files:

src/engine/input_system/input_system.hpp
src/engine/input_system/action_context.cpp

Public Member Functions

Static Public Member Functions

Private Member Functions

Private Attributes

Friends

Detailed Description

Constructor & Destructor Documentation

◆ ActionContext() [1/2]

◆ ActionContext() [2/2]

Member Function Documentation

◆ ApplyInput()

◆ getTriggeredActions()

◆ mapToAction()

◆ propagateAllowed()

◆ registerAction() [1/2]

◆ registerAction() [2/2]

◆ registerInputBind() [1/2]

◆ registerInputBind() [2/2]

◆ resetActionData() [1/2]

◆ resetActionData() [2/2]

◆ setPropagateAllowed()

◆ unregisterAction()

◆ unregisterInputBind()

◆ unregisterInputBinds()