paulxstretch/deps/juce/modules/juce_box2d/box2d/Dynamics/Contacts/b2Contact.cpp

241 lines
7.1 KiB
C++
Raw Normal View History

/*
* Copyright (c) 2006-2009 Erin Catto http://www.box2d.org
*
* This software is provided 'as-is', without any express or implied
* warranty. In no event will the authors be held liable for any damages
* arising from the use of this software.
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute it
* freely, subject to the following restrictions:
* 1. The origin of this software must not be misrepresented; you must not
* claim that you wrote the original software. If you use this software
* in a product, an acknowledgment in the product documentation would be
* appreciated but is not required.
* 2. Altered source versions must be plainly marked as such, and must not be
* misrepresented as being the original software.
* 3. This notice may not be removed or altered from any source distribution.
*/
#include "b2Contact.h"
#include "b2CircleContact.h"
#include "b2PolygonAndCircleContact.h"
#include "b2PolygonContact.h"
#include "b2EdgeAndCircleContact.h"
#include "b2EdgeAndPolygonContact.h"
#include "b2ChainAndCircleContact.h"
#include "b2ChainAndPolygonContact.h"
#include "b2ContactSolver.h"
#include "../../Collision/b2Collision.h"
#include "../../Collision/b2TimeOfImpact.h"
#include "../../Collision/Shapes/b2Shape.h"
#include "../../Common/b2BlockAllocator.h"
#include "../b2Body.h"
#include "../b2Fixture.h"
#include "../b2World.h"
b2ContactRegister b2Contact::s_registers[b2Shape::e_typeCount][b2Shape::e_typeCount];
bool b2Contact::s_initialized = false;
void b2Contact::InitializeRegisters()
{
AddType(b2CircleContact::Create, b2CircleContact::Destroy, b2Shape::e_circle, b2Shape::e_circle);
AddType(b2PolygonAndCircleContact::Create, b2PolygonAndCircleContact::Destroy, b2Shape::e_polygon, b2Shape::e_circle);
AddType(b2PolygonContact::Create, b2PolygonContact::Destroy, b2Shape::e_polygon, b2Shape::e_polygon);
AddType(b2EdgeAndCircleContact::Create, b2EdgeAndCircleContact::Destroy, b2Shape::e_edge, b2Shape::e_circle);
AddType(b2EdgeAndPolygonContact::Create, b2EdgeAndPolygonContact::Destroy, b2Shape::e_edge, b2Shape::e_polygon);
AddType(b2ChainAndCircleContact::Create, b2ChainAndCircleContact::Destroy, b2Shape::e_chain, b2Shape::e_circle);
AddType(b2ChainAndPolygonContact::Create, b2ChainAndPolygonContact::Destroy, b2Shape::e_chain, b2Shape::e_polygon);
}
void b2Contact::AddType(b2ContactCreateFcn* createFcn, b2ContactDestroyFcn* destoryFcn,
b2Shape::Type type1, b2Shape::Type type2)
{
b2Assert(0 <= type1 && type1 < b2Shape::e_typeCount);
b2Assert(0 <= type2 && type2 < b2Shape::e_typeCount);
s_registers[type1][type2].createFcn = createFcn;
s_registers[type1][type2].destroyFcn = destoryFcn;
s_registers[type1][type2].primary = true;
if (type1 != type2)
{
s_registers[type2][type1].createFcn = createFcn;
s_registers[type2][type1].destroyFcn = destoryFcn;
s_registers[type2][type1].primary = false;
}
}
b2Contact* b2Contact::Create(b2Fixture* fixtureA, int32 indexA, b2Fixture* fixtureB, int32 indexB, b2BlockAllocator* allocator)
{
if (s_initialized == false)
{
InitializeRegisters();
s_initialized = true;
}
b2Shape::Type type1 = fixtureA->GetType();
b2Shape::Type type2 = fixtureB->GetType();
b2Assert(0 <= type1 && type1 < b2Shape::e_typeCount);
b2Assert(0 <= type2 && type2 < b2Shape::e_typeCount);
b2ContactCreateFcn* createFcn = s_registers[type1][type2].createFcn;
if (createFcn)
{
if (s_registers[type1][type2].primary)
{
return createFcn(fixtureA, indexA, fixtureB, indexB, allocator);
}
else
{
return createFcn(fixtureB, indexB, fixtureA, indexA, allocator);
}
}
else
{
return NULL;
}
}
void b2Contact::Destroy(b2Contact* contact, b2BlockAllocator* allocator)
{
b2Assert(s_initialized == true);
if (contact->m_manifold.pointCount > 0)
{
contact->GetFixtureA()->GetBody()->SetAwake(true);
contact->GetFixtureB()->GetBody()->SetAwake(true);
}
b2Shape::Type typeA = contact->GetFixtureA()->GetType();
b2Shape::Type typeB = contact->GetFixtureB()->GetType();
b2Assert(0 <= typeA && typeB < b2Shape::e_typeCount);
b2Assert(0 <= typeA && typeB < b2Shape::e_typeCount);
b2ContactDestroyFcn* destroyFcn = s_registers[typeA][typeB].destroyFcn;
destroyFcn(contact, allocator);
}
b2Contact::b2Contact(b2Fixture* fA, int32 indexA, b2Fixture* fB, int32 indexB)
{
m_flags = e_enabledFlag;
m_fixtureA = fA;
m_fixtureB = fB;
m_indexA = indexA;
m_indexB = indexB;
m_manifold.pointCount = 0;
m_prev = NULL;
m_next = NULL;
m_nodeA.contact = NULL;
m_nodeA.prev = NULL;
m_nodeA.next = NULL;
m_nodeA.other = NULL;
m_nodeB.contact = NULL;
m_nodeB.prev = NULL;
m_nodeB.next = NULL;
m_nodeB.other = NULL;
m_toiCount = 0;
m_friction = b2MixFriction(m_fixtureA->m_friction, m_fixtureB->m_friction);
m_restitution = b2MixRestitution(m_fixtureA->m_restitution, m_fixtureB->m_restitution);
}
// Update the contact manifold and touching status.
// Note: do not assume the fixture AABBs are overlapping or are valid.
void b2Contact::Update(b2ContactListener* listener)
{
b2Manifold oldManifold = m_manifold;
// Re-enable this contact.
m_flags |= e_enabledFlag;
bool touching = false;
bool wasTouching = (m_flags & e_touchingFlag) == e_touchingFlag;
bool sensorA = m_fixtureA->IsSensor();
bool sensorB = m_fixtureB->IsSensor();
bool sensor = sensorA || sensorB;
b2Body* bodyA = m_fixtureA->GetBody();
b2Body* bodyB = m_fixtureB->GetBody();
const b2Transform& xfA = bodyA->GetTransform();
const b2Transform& xfB = bodyB->GetTransform();
// Is this contact a sensor?
if (sensor)
{
const b2Shape* shapeA = m_fixtureA->GetShape();
const b2Shape* shapeB = m_fixtureB->GetShape();
touching = b2TestOverlap(shapeA, m_indexA, shapeB, m_indexB, xfA, xfB);
// Sensors don't generate manifolds.
m_manifold.pointCount = 0;
}
else
{
Evaluate(&m_manifold, xfA, xfB);
touching = m_manifold.pointCount > 0;
// Match old contact ids to new contact ids and copy the
// stored impulses to warm start the solver.
for (int32 i = 0; i < m_manifold.pointCount; ++i)
{
b2ManifoldPoint* mp2 = m_manifold.points + i;
mp2->normalImpulse = 0.0f;
mp2->tangentImpulse = 0.0f;
b2ContactID id2 = mp2->id;
for (int32 j = 0; j < oldManifold.pointCount; ++j)
{
b2ManifoldPoint* mp1 = oldManifold.points + j;
if (mp1->id.key == id2.key)
{
mp2->normalImpulse = mp1->normalImpulse;
mp2->tangentImpulse = mp1->tangentImpulse;
break;
}
}
}
if (touching != wasTouching)
{
bodyA->SetAwake(true);
bodyB->SetAwake(true);
}
}
if (touching)
{
m_flags |= e_touchingFlag;
}
else
{
m_flags &= ~e_touchingFlag;
}
if (wasTouching == false && touching == true && listener)
{
listener->BeginContact(this);
}
if (wasTouching == true && touching == false && listener)
{
listener->EndContact(this);
}
if (sensor == false && touching && listener)
{
listener->PreSolve(this, &oldManifold);
}
}