pulp::state::ExternalBinding Class Reference

Reactive binding between a UI widget and an arbitrary external value source, interface-compatible with state::Binding but backed by getter/setter lambdas instead of a StateStore parameter. More...

#include <external_binding.hpp>

Public Types
using	ChangeCallback = std::function<void(float new_value)>

Public Member Functions
	ExternalBinding ()=default
	ExternalBinding (ExternalBindingConfig cfg)
float	get () const
	Read the current plain value.
void	set (float value)
	Write a new plain value.
float	get_normalized () const
	Read the value mapped to [0, 1] through the configured range.
void	set_normalized (float normalized)
	Write from a normalized [0, 1] value through the configured range.
void	begin_gesture ()
	Notify the host that a user gesture has begun / ended (optional).
void	end_gesture ()
void	on_change (ChangeCallback cb)
	Register a callback that fires when the value changes via set/poll/notify.
bool	poll ()
	Poll the source; fire on_change if it moved since the last observation.
void	notify ()
	UI-thread accelerator: the host knows the external value changed and wants an immediate refresh without waiting for the next poll().
void	reset ()
	Reset to the range's default value and fire change callbacks.
const std::string &	name () const
const std::string &	unit () const
const ParamRange &	range () const
bool	is_bound () const
	True if a getter is configured (an unbound ExternalBinding reads 0).

Detailed Description

Reactive binding between a UI widget and an arbitrary external value source, interface-compatible with state::Binding but backed by getter/setter lambdas instead of a StateStore parameter.

This is a SEPARATE type, not a base/override of Binding: the StateStore path (state::Binding) stays direct and vtable-free, paying nothing for this flexibility. Widgets bind to either via the param_attachment overloads.

Change notification: poll() reads the getter and fires on_change when the value moved — the fallback for a source with no listener list. A host that KNOWS when the external value changed may call notify() for an immediate refresh, but poll() remains the safety net (a host may forget to notify).

Note

Thread safety: get/set/poll/notify and the getter/setter callbacks run on the UI thread only. Any host-owned state they touch is the host's responsibility. These are NOT audio-thread APIs. Modulation is not modeled (a plain external value has no mod offset).

Member Typedef Documentation

ChangeCallback

using pulp::state::ExternalBinding::ChangeCallback = std::function<void(float new_value)>

Constructor & Destructor Documentation

ExternalBinding() [1/2]

pulp::state::ExternalBinding::ExternalBinding ( )

default

ExternalBinding() [2/2]

pulp::state::ExternalBinding::ExternalBinding ( ExternalBindingConfig cfg )

inlineexplicit

Member Function Documentation

begin_gesture()

void pulp::state::ExternalBinding::begin_gesture ( )

inline

Notify the host that a user gesture has begun / ended (optional).

end_gesture()

void pulp::state::ExternalBinding::end_gesture ( )

inline

get()

float pulp::state::ExternalBinding::get ( ) const

inline

Read the current plain value.

get_normalized()

float pulp::state::ExternalBinding::get_normalized ( ) const

inline

Read the value mapped to [0, 1] through the configured range.

is_bound()

bool pulp::state::ExternalBinding::is_bound ( ) const

inline

True if a getter is configured (an unbound ExternalBinding reads 0).

name()

const std::string & pulp::state::ExternalBinding::name ( ) const

inline

notify()

void pulp::state::ExternalBinding::notify ( )

inline

UI-thread accelerator: the host knows the external value changed and wants an immediate refresh without waiting for the next poll().

on_change()

void pulp::state::ExternalBinding::on_change ( ChangeCallback cb )

inline

Register a callback that fires when the value changes via set/poll/notify.

poll()

bool pulp::state::ExternalBinding::poll ( )

inline

Poll the source; fire on_change if it moved since the last observation.

Fallback for external sources without their own change signal.

range()

const ParamRange & pulp::state::ExternalBinding::range ( ) const

inline

reset()

void pulp::state::ExternalBinding::reset ( )

inline

Reset to the range's default value and fire change callbacks.

set()

void pulp::state::ExternalBinding::set ( float value )

inline

Write a new plain value.

Fires change callbacks if the value actually changed (the source may re-clamp/quantize, so we re-read afterwards).

set_normalized()

void pulp::state::ExternalBinding::set_normalized ( float normalized )

inline

Write from a normalized [0, 1] value through the configured range.

unit()

const std::string & pulp::state::ExternalBinding::unit ( ) const

inline

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

• /home/runner/work/pulp/pulp/core/state/include/pulp/state/external_binding.hpp