b2_fixture.h

// 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();
    const b2FixtureUserData& GetUserData() const;
 
    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 const b2FixtureUserData& b2Fixture::GetUserData() const
{
    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