Rename Box2D folder to box2d

src/libraries/box2d/b2_broad_phase.h

@@ -0,0 +1,237 @@
+// 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_BROAD_PHASE_H
+#define B2_BROAD_PHASE_H
+
+#include "b2_settings.h"
+#include "b2_collision.h"
+#include "b2_dynamic_tree.h"
+
+struct b2Pair
+{
+	int32 proxyIdA;
+	int32 proxyIdB;
+};
+
+/// The broad-phase is used for computing pairs and performing volume queries and ray casts.
+/// This broad-phase does not persist pairs. Instead, this reports potentially new pairs.
+/// It is up to the client to consume the new pairs and to track subsequent overlap.
+class b2BroadPhase
+{
+public:
+
+	enum
+	{
+		e_nullProxy = -1
+	};
+
+	b2BroadPhase();
+	~b2BroadPhase();
+
+	/// Create a proxy with an initial AABB. Pairs are not reported until
+	/// UpdatePairs is called.
+	int32 CreateProxy(const b2AABB& aabb, void* userData);
+
+	/// Destroy a proxy. It is up to the client to remove any pairs.
+	void DestroyProxy(int32 proxyId);
+
+	/// Call MoveProxy as many times as you like, then when you are done
+	/// call UpdatePairs to finalized the proxy pairs (for your time step).
+	void MoveProxy(int32 proxyId, const b2AABB& aabb, const b2Vec2& displacement);
+
+	/// Call to trigger a re-processing of it's pairs on the next call to UpdatePairs.
+	void TouchProxy(int32 proxyId);
+
+	/// Get the fat AABB for a proxy.
+	const b2AABB& GetFatAABB(int32 proxyId) const;
+
+	/// Get user data from a proxy. Returns nullptr if the id is invalid.
+	void* GetUserData(int32 proxyId) const;
+
+	/// Test overlap of fat AABBs.
+	bool TestOverlap(int32 proxyIdA, int32 proxyIdB) const;
+
+	/// Get the number of proxies.
+	int32 GetProxyCount() const;
+
+	/// Update the pairs. This results in pair callbacks. This can only add pairs.
+	template <typename T>
+	void UpdatePairs(T* callback);
+
+	/// Query an AABB for overlapping proxies. The callback class
+	/// is called for each proxy that overlaps the supplied AABB.
+	template <typename T>
+	void Query(T* callback, const b2AABB& aabb) const;
+
+	/// Ray-cast against the proxies in the tree. This relies on the callback
+	/// to perform a exact ray-cast in the case were the proxy contains a shape.
+	/// The callback also performs the any collision filtering. This has performance
+	/// roughly equal to k * log(n), where k is the number of collisions and n is the
+	/// number of proxies in the tree.
+	/// @param input the ray-cast input data. The ray extends from p1 to p1 + maxFraction * (p2 - p1).
+	/// @param callback a callback class that is called for each proxy that is hit by the ray.
+	template <typename T>
+	void RayCast(T* callback, const b2RayCastInput& input) const;
+
+	/// Get the height of the embedded tree.
+	int32 GetTreeHeight() const;
+
+	/// Get the balance of the embedded tree.
+	int32 GetTreeBalance() const;
+
+	/// Get the quality metric of the embedded tree.
+	float GetTreeQuality() const;
+
+	/// Shift the world origin. Useful for large worlds.
+	/// The shift formula is: position -= newOrigin
+	/// @param newOrigin the new origin with respect to the old origin
+	void ShiftOrigin(const b2Vec2& newOrigin);
+
+private:
+
+	friend class b2DynamicTree;
+
+	void BufferMove(int32 proxyId);
+	void UnBufferMove(int32 proxyId);
+
+	bool QueryCallback(int32 proxyId);
+
+	b2DynamicTree m_tree;
+
+	int32 m_proxyCount;
+
+	int32* m_moveBuffer;
+	int32 m_moveCapacity;
+	int32 m_moveCount;
+
+	b2Pair* m_pairBuffer;
+	int32 m_pairCapacity;
+	int32 m_pairCount;
+
+	int32 m_queryProxyId;
+};
+
+inline void* b2BroadPhase::GetUserData(int32 proxyId) const
+{
+	return m_tree.GetUserData(proxyId);
+}
+
+inline bool b2BroadPhase::TestOverlap(int32 proxyIdA, int32 proxyIdB) const
+{
+	const b2AABB& aabbA = m_tree.GetFatAABB(proxyIdA);
+	const b2AABB& aabbB = m_tree.GetFatAABB(proxyIdB);
+	return b2TestOverlap(aabbA, aabbB);
+}
+
+inline const b2AABB& b2BroadPhase::GetFatAABB(int32 proxyId) const
+{
+	return m_tree.GetFatAABB(proxyId);
+}
+
+inline int32 b2BroadPhase::GetProxyCount() const
+{
+	return m_proxyCount;
+}
+
+inline int32 b2BroadPhase::GetTreeHeight() const
+{
+	return m_tree.GetHeight();
+}
+
+inline int32 b2BroadPhase::GetTreeBalance() const
+{
+	return m_tree.GetMaxBalance();
+}
+
+inline float b2BroadPhase::GetTreeQuality() const
+{
+	return m_tree.GetAreaRatio();
+}
+
+template <typename T>
+void b2BroadPhase::UpdatePairs(T* callback)
+{
+	// Reset pair buffer
+	m_pairCount = 0;
+
+	// Perform tree queries for all moving proxies.
+	for (int32 i = 0; i < m_moveCount; ++i)
+	{
+		m_queryProxyId = m_moveBuffer[i];
+		if (m_queryProxyId == e_nullProxy)
+		{
+			continue;
+		}
+
+		// We have to query the tree with the fat AABB so that
+		// we don't fail to create a pair that may touch later.
+		const b2AABB& fatAABB = m_tree.GetFatAABB(m_queryProxyId);
+
+		// Query tree, create pairs and add them pair buffer.
+		m_tree.Query(this, fatAABB);
+	}
+
+	// Send pairs to caller
+	for (int32 i = 0; i < m_pairCount; ++i)
+	{
+		b2Pair* primaryPair = m_pairBuffer + i;
+		void* userDataA = m_tree.GetUserData(primaryPair->proxyIdA);
+		void* userDataB = m_tree.GetUserData(primaryPair->proxyIdB);
+
+		callback->AddPair(userDataA, userDataB);
+	}
+
+	// Clear move flags
+	for (int32 i = 0; i < m_moveCount; ++i)
+	{
+		int32 proxyId = m_moveBuffer[i];
+		if (proxyId == e_nullProxy)
+		{
+			continue;
+		}
+
+		m_tree.ClearMoved(proxyId);
+	}
+
+	// Reset move buffer
+	m_moveCount = 0;
+}
+
+template <typename T>
+inline void b2BroadPhase::Query(T* callback, const b2AABB& aabb) const
+{
+	m_tree.Query(callback, aabb);
+}
+
+template <typename T>
+inline void b2BroadPhase::RayCast(T* callback, const b2RayCastInput& input) const
+{
+	m_tree.RayCast(callback, input);
+}
+
+inline void b2BroadPhase::ShiftOrigin(const b2Vec2& newOrigin)
+{
+	m_tree.ShiftOrigin(newOrigin);
+}
+
+#endif