b2_fixture.h

Go to the documentation of this file.

// 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_FIXTURE_H
#define B2_FIXTURE_H

#include "b2_api.h"
#include "b2_body.h"
#include "b2_collision.h"
#include "b2_shape.h"

class b2BlockAllocator;
class b2Body;
class b2BroadPhase;
class b2Fixture;

struct B2_API b2Filter
{
        b2Filter()
        {
                categoryBits = 0x0001;
                maskBits = 0xFFFF;
                groupIndex = 0;
        }

        uint16 categoryBits;

        uint16 maskBits;

        int16 groupIndex;
};

struct B2_API b2FixtureDef
{
        b2FixtureDef()
        {
                shape = nullptr;
                friction = 0.2f;
                restitution = 0.0f;
                restitutionThreshold = 1.0f * b2_lengthUnitsPerMeter;
                density = 0.0f;
                isSensor = false;
        }

        const b2Shape* shape;

        b2FixtureUserData userData;

        float friction;

        float restitution;

        float restitutionThreshold;

        float density;

        bool isSensor;

        b2Filter filter;
};

struct B2_API b2FixtureProxy
{
        b2AABB aabb;
        b2Fixture* fixture;
        int32 childIndex;
        int32 proxyId;
};

class B2_API b2Fixture
{
public:
        b2Shape::Type GetType() const;

        b2Shape* GetShape();
        const b2Shape* GetShape() const;

        void SetSensor(bool sensor);

        bool IsSensor() const;

        void SetFilterData(const b2Filter& filter);

        const b2Filter& GetFilterData() const;

        void Refilter();

        b2Body* GetBody();
        const b2Body* GetBody() const;

        b2Fixture* GetNext();
        const b2Fixture* GetNext() const;

        b2FixtureUserData& GetUserData();

        bool TestPoint(const b2Vec2& p) const;

        bool RayCast(b2RayCastOutput* output, const b2RayCastInput& input, int32 childIndex) const;

        void GetMassData(b2MassData* massData) const;

        void SetDensity(float density);

        float GetDensity() const;

        float GetFriction() const;

        void SetFriction(float friction);

        float GetRestitution() const;

        void SetRestitution(float restitution);

        float GetRestitutionThreshold() const;

        void SetRestitutionThreshold(float threshold);

        const b2AABB& GetAABB(int32 childIndex) const;

        void Dump(int32 bodyIndex);

protected:

        friend class b2Body;
        friend class b2World;
        friend class b2Contact;
        friend class b2ContactManager;

        b2Fixture();

        // We need separation create/destroy functions from the constructor/destructor because
        // the destructor cannot access the allocator (no destructor arguments allowed by C++).
        void Create(b2BlockAllocator* allocator, b2Body* body, const b2FixtureDef* def);
        void Destroy(b2BlockAllocator* allocator);

        // These support body activation/deactivation.
        void CreateProxies(b2BroadPhase* broadPhase, const b2Transform& xf);
        void DestroyProxies(b2BroadPhase* broadPhase);

        void Synchronize(b2BroadPhase* broadPhase, const b2Transform& xf1, const b2Transform& xf2);

        float m_density;

        b2Fixture* m_next;
        b2Body* m_body;

        b2Shape* m_shape;

        float m_friction;
        float m_restitution;
        float m_restitutionThreshold;

        b2FixtureProxy* m_proxies;
        int32 m_proxyCount;

        b2Filter m_filter;

        bool m_isSensor;

        b2FixtureUserData m_userData;
};

inline b2Shape::Type b2Fixture::GetType() const
{
        return m_shape->GetType();
}

inline b2Shape* b2Fixture::GetShape()
{
        return m_shape;
}

inline const b2Shape* b2Fixture::GetShape() const
{
        return m_shape;
}

inline bool b2Fixture::IsSensor() const
{
        return m_isSensor;
}

inline const b2Filter& b2Fixture::GetFilterData() const
{
        return m_filter;
}

inline b2FixtureUserData& b2Fixture::GetUserData()
{
        return m_userData;
}

inline b2Body* b2Fixture::GetBody()
{
        return m_body;
}

inline const b2Body* b2Fixture::GetBody() const
{
        return m_body;
}

inline b2Fixture* b2Fixture::GetNext()
{
        return m_next;
}

inline const b2Fixture* b2Fixture::GetNext() const
{
        return m_next;
}

inline void b2Fixture::SetDensity(float density)
{
        b2Assert(b2IsValid(density) && density >= 0.0f);
        m_density = density;
}

inline float b2Fixture::GetDensity() const
{
        return m_density;
}

inline float b2Fixture::GetFriction() const
{
        return m_friction;
}

inline void b2Fixture::SetFriction(float friction)
{
        m_friction = friction;
}

inline float b2Fixture::GetRestitution() const
{
        return m_restitution;
}

inline void b2Fixture::SetRestitution(float restitution)
{
        m_restitution = restitution;
}

inline float b2Fixture::GetRestitutionThreshold() const
{
        return m_restitutionThreshold;
}

inline void b2Fixture::SetRestitutionThreshold(float threshold)
{
        m_restitutionThreshold = threshold;
}

inline bool b2Fixture::TestPoint(const b2Vec2& p) const
{
        return m_shape->TestPoint(m_body->GetTransform(), p);
}

inline bool b2Fixture::RayCast(b2RayCastOutput* output, const b2RayCastInput& input, int32 childIndex) const
{
        return m_shape->RayCast(output, input, m_body->GetTransform(), childIndex);
}

inline void b2Fixture::GetMassData(b2MassData* massData) const
{
        m_shape->ComputeMass(massData, m_density);
}

inline const b2AABB& b2Fixture::GetAABB(int32 childIndex) const
{
        b2Assert(0 <= childIndex && childIndex < m_proxyCount);
        return m_proxies[childIndex].aabb;
}

#endif