Rename Box2D folder to box2d

src/libraries/box2d/b2_world_callbacks.h

@@ -0,0 +1,160 @@
+// 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_WORLD_CALLBACKS_H
+#define B2_WORLD_CALLBACKS_H
+
+#include "b2_settings.h"
+
+struct b2Vec2;
+struct b2Transform;
+class b2Fixture;
+class b2Body;
+class b2Joint;
+class b2Contact;
+struct b2ContactResult;
+struct b2Manifold;
+
+/// Joints and fixtures are destroyed when their associated
+/// body is destroyed. Implement this listener so that you
+/// may nullify references to these joints and shapes.
+class b2DestructionListener
+{
+public:
+	virtual ~b2DestructionListener() {}
+
+	/// Called when any joint is about to be destroyed due
+	/// to the destruction of one of its attached bodies.
+	virtual void SayGoodbye(b2Joint* joint) = 0;
+
+	/// Called when any fixture is about to be destroyed due
+	/// to the destruction of its parent body.
+	virtual void SayGoodbye(b2Fixture* fixture) = 0;
+};
+
+/// Implement this class to provide collision filtering. In other words, you can implement
+/// this class if you want finer control over contact creation.
+class b2ContactFilter
+{
+public:
+	virtual ~b2ContactFilter() {}
+
+	/// Return true if contact calculations should be performed between these two shapes.
+	/// @warning for performance reasons this is only called when the AABBs begin to overlap.
+	virtual bool ShouldCollide(b2Fixture* fixtureA, b2Fixture* fixtureB);
+};
+
+/// Contact impulses for reporting. Impulses are used instead of forces because
+/// sub-step forces may approach infinity for rigid body collisions. These
+/// match up one-to-one with the contact points in b2Manifold.
+struct b2ContactImpulse
+{
+	float normalImpulses[b2_maxManifoldPoints];
+	float tangentImpulses[b2_maxManifoldPoints];
+	int32 count;
+};
+
+/// Implement this class to get contact information. You can use these results for
+/// things like sounds and game logic. You can also get contact results by
+/// traversing the contact lists after the time step. However, you might miss
+/// some contacts because continuous physics leads to sub-stepping.
+/// Additionally you may receive multiple callbacks for the same contact in a
+/// single time step.
+/// You should strive to make your callbacks efficient because there may be
+/// many callbacks per time step.
+/// @warning You cannot create/destroy Box2D entities inside these callbacks.
+class b2ContactListener
+{
+public:
+	virtual ~b2ContactListener() {}
+
+	/// Called when two fixtures begin to touch.
+	virtual void BeginContact(b2Contact* contact) { B2_NOT_USED(contact); }
+
+	/// Called when two fixtures cease to touch.
+	virtual void EndContact(b2Contact* contact) { B2_NOT_USED(contact); }
+
+	/// This is called after a contact is updated. This allows you to inspect a
+	/// contact before it goes to the solver. If you are careful, you can modify the
+	/// contact manifold (e.g. disable contact).
+	/// A copy of the old manifold is provided so that you can detect changes.
+	/// Note: this is called only for awake bodies.
+	/// Note: this is called even when the number of contact points is zero.
+	/// Note: this is not called for sensors.
+	/// Note: if you set the number of contact points to zero, you will not
+	/// get an EndContact callback. However, you may get a BeginContact callback
+	/// the next step.
+	virtual void PreSolve(b2Contact* contact, const b2Manifold* oldManifold)
+	{
+		B2_NOT_USED(contact);
+		B2_NOT_USED(oldManifold);
+	}
+
+	/// This lets you inspect a contact after the solver is finished. This is useful
+	/// for inspecting impulses.
+	/// Note: the contact manifold does not include time of impact impulses, which can be
+	/// arbitrarily large if the sub-step is small. Hence the impulse is provided explicitly
+	/// in a separate data structure.
+	/// Note: this is only called for contacts that are touching, solid, and awake.
+	virtual void PostSolve(b2Contact* contact, const b2ContactImpulse* impulse)
+	{
+		B2_NOT_USED(contact);
+		B2_NOT_USED(impulse);
+	}
+};
+
+/// Callback class for AABB queries.
+/// See b2World::Query
+class b2QueryCallback
+{
+public:
+	virtual ~b2QueryCallback() {}
+
+	/// Called for each fixture found in the query AABB.
+	/// @return false to terminate the query.
+	virtual bool ReportFixture(b2Fixture* fixture) = 0;
+};
+
+/// Callback class for ray casts.
+/// See b2World::RayCast
+class b2RayCastCallback
+{
+public:
+	virtual ~b2RayCastCallback() {}
+
+	/// Called for each fixture found in the query. You control how the ray cast
+	/// proceeds by returning a float:
+	/// return -1: ignore this fixture and continue
+	/// return 0: terminate the ray cast
+	/// return fraction: clip the ray to this point
+	/// return 1: don't clip the ray and continue
+	/// @param fixture the fixture hit by the ray
+	/// @param point the point of initial intersection
+	/// @param normal the normal vector at the point of intersection
+	/// @param fraction the fraction along the ray at the point of intersection
+	/// @return -1 to filter, 0 to terminate, fraction to clip the ray for
+	/// closest hit, 1 to continue
+	virtual float ReportFixture(	b2Fixture* fixture, const b2Vec2& point,
+									const b2Vec2& normal, float fraction) = 0;
+};
+
+#endif