b2_island.h

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// MIT License

// Copyright (c) 2019 Erin Catto

// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:

// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.

// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.

#ifndef B2_ISLAND_H
#define B2_ISLAND_H

#include "box2d/b2_body.h"
#include "box2d/b2_math.h"
#include "box2d/b2_time_step.h"

class b2Contact;
class b2Joint;
class b2StackAllocator;
class b2ContactListener;
struct b2ContactVelocityConstraint;
struct b2Profile;

class b2Island
{
public:
        b2Island(int32 bodyCapacity, int32 contactCapacity, int32 jointCapacity,
                        b2StackAllocator* allocator, b2ContactListener* listener);
        ~b2Island();

        void Clear()
        {
                m_bodyCount = 0;
                m_contactCount = 0;
                m_jointCount = 0;
        }

        void Solve(b2Profile* profile, const b2TimeStep& step, const b2Vec2& gravity, bool allowSleep);

        void SolveTOI(const b2TimeStep& subStep, int32 toiIndexA, int32 toiIndexB);

        void Add(b2Body* body)
        {
                b2Assert(m_bodyCount < m_bodyCapacity);
                body->m_islandIndex = m_bodyCount;
                m_bodies[m_bodyCount] = body;
                ++m_bodyCount;
        }

        void Add(b2Contact* contact)
        {
                b2Assert(m_contactCount < m_contactCapacity);
                m_contacts[m_contactCount++] = contact;
        }

        void Add(b2Joint* joint)
        {
                b2Assert(m_jointCount < m_jointCapacity);
                m_joints[m_jointCount++] = joint;
        }

        void Report(const b2ContactVelocityConstraint* constraints);

        b2StackAllocator* m_allocator;
        b2ContactListener* m_listener;

        b2Body** m_bodies;
        b2Contact** m_contacts;
        b2Joint** m_joints;

        b2Position* m_positions;
        b2Velocity* m_velocities;

        int32 m_bodyCount;
        int32 m_jointCount;
        int32 m_contactCount;

        int32 m_bodyCapacity;
        int32 m_contactCapacity;
        int32 m_jointCapacity;
};

#endif