axmol/Box2D/Dynamics/Joints/b2Joint.cpp

/*
* Copyright (c) 2006-2007 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 <Box2D/Dynamics/Joints/b2Joint.h>
#include <Box2D/Dynamics/Joints/b2DistanceJoint.h>
#include <Box2D/Dynamics/Joints/b2WheelJoint.h>
#include <Box2D/Dynamics/Joints/b2MouseJoint.h>
#include <Box2D/Dynamics/Joints/b2RevoluteJoint.h>
#include <Box2D/Dynamics/Joints/b2PrismaticJoint.h>
#include <Box2D/Dynamics/Joints/b2PulleyJoint.h>
#include <Box2D/Dynamics/Joints/b2GearJoint.h>
#include <Box2D/Dynamics/Joints/b2WeldJoint.h>
#include <Box2D/Dynamics/Joints/b2FrictionJoint.h>
#include <Box2D/Dynamics/Joints/b2RopeJoint.h>
#include <Box2D/Dynamics/b2Body.h>
#include <Box2D/Dynamics/b2World.h>
#include <Box2D/Common/b2BlockAllocator.h>

#include <new>

b2Joint* b2Joint::Create(const b2JointDef* def, b2BlockAllocator* allocator)
{
    b2Joint* joint = NULL;

    switch (def->type)
    {
    case e_distanceJoint:
        {
            void* mem = allocator->Allocate(sizeof(b2DistanceJoint));
            joint = new (mem) b2DistanceJoint((b2DistanceJointDef*)def);
        }
        break;

    case e_mouseJoint:
        {
            void* mem = allocator->Allocate(sizeof(b2MouseJoint));
            joint = new (mem) b2MouseJoint((b2MouseJointDef*)def);
        }
        break;

    case e_prismaticJoint:
        {
            void* mem = allocator->Allocate(sizeof(b2PrismaticJoint));
            joint = new (mem) b2PrismaticJoint((b2PrismaticJointDef*)def);
        }
        break;

    case e_revoluteJoint:
        {
            void* mem = allocator->Allocate(sizeof(b2RevoluteJoint));
            joint = new (mem) b2RevoluteJoint((b2RevoluteJointDef*)def);
        }
        break;

    case e_pulleyJoint:
        {
            void* mem = allocator->Allocate(sizeof(b2PulleyJoint));
            joint = new (mem) b2PulleyJoint((b2PulleyJointDef*)def);
        }
        break;

    case e_gearJoint:
        {
            void* mem = allocator->Allocate(sizeof(b2GearJoint));
            joint = new (mem) b2GearJoint((b2GearJointDef*)def);
        }
        break;

    case e_wheelJoint:
        {
            void* mem = allocator->Allocate(sizeof(b2WheelJoint));
            joint = new (mem) b2WheelJoint((b2WheelJointDef*)def);
        }
        break;

    case e_weldJoint:
        {
            void* mem = allocator->Allocate(sizeof(b2WeldJoint));
            joint = new (mem) b2WeldJoint((b2WeldJointDef*)def);
        }
        break;
        
    case e_frictionJoint:
        {
            void* mem = allocator->Allocate(sizeof(b2FrictionJoint));
            joint = new (mem) b2FrictionJoint((b2FrictionJointDef*)def);
        }
        break;

    case e_ropeJoint:
        {
            void* mem = allocator->Allocate(sizeof(b2RopeJoint));
            joint = new (mem) b2RopeJoint((b2RopeJointDef*)def);
        }
        break;

    default:
        b2Assert(false);
        break;
    }

    return joint;
}

void b2Joint::Destroy(b2Joint* joint, b2BlockAllocator* allocator)
{
    joint->~b2Joint();
    switch (joint->m_type)
    {
    case e_distanceJoint:
        allocator->Free(joint, sizeof(b2DistanceJoint));
        break;

    case e_mouseJoint:
        allocator->Free(joint, sizeof(b2MouseJoint));
        break;

    case e_prismaticJoint:
        allocator->Free(joint, sizeof(b2PrismaticJoint));
        break;

    case e_revoluteJoint:
        allocator->Free(joint, sizeof(b2RevoluteJoint));
        break;

    case e_pulleyJoint:
        allocator->Free(joint, sizeof(b2PulleyJoint));
        break;

    case e_gearJoint:
        allocator->Free(joint, sizeof(b2GearJoint));
        break;

    case e_wheelJoint:
        allocator->Free(joint, sizeof(b2WheelJoint));
        break;
    
    case e_weldJoint:
        allocator->Free(joint, sizeof(b2WeldJoint));
        break;

    case e_frictionJoint:
        allocator->Free(joint, sizeof(b2FrictionJoint));
        break;

    case e_ropeJoint:
        allocator->Free(joint, sizeof(b2RopeJoint));
        break;

    default:
        b2Assert(false);
        break;
    }
}

b2Joint::b2Joint(const b2JointDef* def)
{
    b2Assert(def->bodyA != def->bodyB);

    m_type = def->type;
    m_prev = NULL;
    m_next = NULL;
    m_bodyA = def->bodyA;
    m_bodyB = def->bodyB;
    m_index = 0;
    m_collideConnected = def->collideConnected;
    m_islandFlag = false;
    m_userData = def->userData;

    m_edgeA.joint = NULL;
    m_edgeA.other = NULL;
    m_edgeA.prev = NULL;
    m_edgeA.next = NULL;

    m_edgeB.joint = NULL;
    m_edgeB.other = NULL;
    m_edgeB.prev = NULL;
    m_edgeB.next = NULL;
}

bool b2Joint::IsActive() const
{
    return m_bodyA->IsActive() && m_bodyB->IsActive();
}