Physics::Utils::ContactListenerImpl Class Reference

ContactListener implementation. More...

#include <ContactListenerImpl.hpp>

Inheritance diagram for Physics::Utils::ContactListenerImpl:

Public Member Functions
	ContactListenerImpl ()=delete
	ContactListenerImpl (Engine::Core &core)
	~ContactListenerImpl () override=default
JPH::ValidateResult	OnContactValidate (const JPH::Body &inBody1, const JPH::Body &inBody2, JPH::RVec3Arg inBaseOffset, const JPH::CollideShapeResult &inCollisionResult) override
void	OnContactAdded (const JPH::Body &inBody1, const JPH::Body &inBody2, const JPH::ContactManifold &inManifold, JPH::ContactSettings &ioSettings) override
	Called when two bodies start to make contact.
void	OnContactPersisted (const JPH::Body &inBody1, const JPH::Body &inBody2, const JPH::ContactManifold &inManifold, JPH::ContactSettings &ioSettings) override
	Called when two bodies continue to make contact.
void	OnContactRemoved (const JPH::SubShapeIDPair &inSubShapePair) override
	Called when two bodies cease to make contact.
void	ProcessBufferedEvents (Engine::Core &core)
	Flush buffered events to the main thread EventManager (should be called from main thread).

Private Attributes
Engine::Core &	_core
std::mutex	_bufferMutex
std::vector< Physics::Event::CollisionAddedEvent >	_bufferedAdded
std::vector< Physics::Event::CollisionPersistedEvent >	_bufferedPersisted
std::vector< Physics::Event::CollisionRemovedEvent >	_bufferedRemoved

Detailed Description

ContactListener implementation.

This is used to define callbacks for contact events between bodies. Callbacks will be called with the Core, as well as the two entities that collided.

Note

Jolt will call these callbacks from physics worker threads. To avoid concurrent access to engine resources (like the entt registry) and the EventManager, events are buffered in worker threads and flushed to the main thread by calling ProcessBufferedEvents(core) from the main physics update system. Do NOT call EventManager::PushEvent() directly in these callbacks.

Constructor & Destructor Documentation

ContactListenerImpl() [1/2]

Physics::Utils::ContactListenerImpl::ContactListenerImpl ( )

delete

ContactListenerImpl() [2/2]

Physics::Utils::ContactListenerImpl::ContactListenerImpl ( Engine::Core & core )

inlineexplicit

~ContactListenerImpl()

Physics::Utils::ContactListenerImpl::~ContactListenerImpl ( )

overridedefault

Member Function Documentation

OnContactAdded()

void Physics::Utils::ContactListenerImpl::OnContactAdded ( const JPH::Body & inBody1, const JPH::Body & inBody2, const JPH::ContactManifold & inManifold, JPH::ContactSettings & ioSettings )

override

Called when two bodies start to make contact.

Right now we use 32 bits for entities IDs with EnTT but Jolt stores user data as 64 bits so we have to mask the upper 32 bits auto entity1 = static_cast<Engine::Entity>(inBody1.GetUserData() & ENTITY_ID_MASK); auto entity2 = static_cast<Engine::Entity>(inBody2.GetUserData() & ENTITY_ID_MASK);

Validate entity ids and buffer the event on a worker thread; it will be flushed on the main thread by the PhysicsUpdate system.

Buffer the event. Can't safely access the registry from a physics worker thread, so defer any entity validity checks until ProcessBufferedEvents (main thread).

Parameters

inBody1	The first body involved in the contact.
inBody2	The second body involved in the contact.
inManifold	The contact manifold containing contact points.
ioSettings	Contact settings that can be modified.

OnContactPersisted()

void Physics::Utils::ContactListenerImpl::OnContactPersisted ( const JPH::Body & inBody1, const JPH::Body & inBody2, const JPH::ContactManifold & inManifold, JPH::ContactSettings & ioSettings )

override

Called when two bodies continue to make contact.

Same as OnContactAdded: delay entity validation until ProcessBufferedEvents (main thread)

Parameters

inBody1	The first body involved in the contact.
inBody2	The second body involved in the contact.
inManifold	The contact manifold containing contact points.
ioSettings	Contact settings that can be modified.

OnContactRemoved()

void Physics::Utils::ContactListenerImpl::OnContactRemoved ( const JPH::SubShapeIDPair & inSubShapePair )

override

Called when two bodies cease to make contact.

Buffer the event on a worker thread; it will be flushed on the main thread by the PhysicsUpdate system.

Parameters

inSubShapePair

The pair of sub-shapes that were in contact.

OnContactValidate()

JPH::ValidateResult Physics::Utils::ContactListenerImpl::OnContactValidate ( const JPH::Body & inBody1, const JPH::Body & inBody2, JPH::RVec3Arg inBaseOffset, const JPH::CollideShapeResult & inCollisionResult )

inlineoverride

ProcessBufferedEvents()

void Physics::Utils::ContactListenerImpl::ProcessBufferedEvents

(

Engine::Core &

core

)

Flush buffered events to the main thread EventManager (should be called from main thread).

Move buffers into local copies under lock then push events to the EventManager from main thread.

Member Data Documentation

_bufferedAdded

std::vector<Physics::Event::CollisionAddedEvent> Physics::Utils::ContactListenerImpl::_bufferedAdded

private

_bufferedPersisted

std::vector<Physics::Event::CollisionPersistedEvent> Physics::Utils::ContactListenerImpl::_bufferedPersisted

private

_bufferedRemoved

std::vector<Physics::Event::CollisionRemovedEvent> Physics::Utils::ContactListenerImpl::_bufferedRemoved

private

_bufferMutex

std::mutex Physics::Utils::ContactListenerImpl::_bufferMutex

private

_core

Engine::Core& Physics::Utils::ContactListenerImpl::_core

private

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

• src/plugin/physics/src/utils/ContactListenerImpl.hpp
• src/plugin/physics/src/utils/ContactListenerImpl.cpp