Praxis3D/Dependencies/include/bullet3/Bullet3Collision/BroadPhaseCollision/shared/b3Aabb.h

#ifndef B3_AABB_H
#define B3_AABB_H

#include "Bullet3Common/shared/b3Float4.h"
#include "Bullet3Common/shared/b3Mat3x3.h"

typedef struct b3Aabb b3Aabb_t;

struct b3Aabb
{
	union {
		float m_min[4];
		b3Float4 m_minVec;
		int m_minIndices[4];
	};
	union {
		float m_max[4];
		b3Float4 m_maxVec;
		int m_signedMaxIndices[4];
	};
};

inline void b3TransformAabb2(b3Float4ConstArg localAabbMin, b3Float4ConstArg localAabbMax, float margin,
							 b3Float4ConstArg pos,
							 b3QuatConstArg orn,
							 b3Float4* aabbMinOut, b3Float4* aabbMaxOut)
{
	b3Float4 localHalfExtents = 0.5f * (localAabbMax - localAabbMin);
	localHalfExtents += b3MakeFloat4(margin, margin, margin, 0.f);
	b3Float4 localCenter = 0.5f * (localAabbMax + localAabbMin);
	b3Mat3x3 m;
	m = b3QuatGetRotationMatrix(orn);
	b3Mat3x3 abs_b = b3AbsoluteMat3x3(m);
	b3Float4 center = b3TransformPoint(localCenter, pos, orn);

	b3Float4 extent = b3MakeFloat4(b3Dot3F4(localHalfExtents, b3GetRow(abs_b, 0)),
								   b3Dot3F4(localHalfExtents, b3GetRow(abs_b, 1)),
								   b3Dot3F4(localHalfExtents, b3GetRow(abs_b, 2)),
								   0.f);
	*aabbMinOut = center - extent;
	*aabbMaxOut = center + extent;
}

/// conservative test for overlap between two aabbs
inline bool b3TestAabbAgainstAabb(b3Float4ConstArg aabbMin1, b3Float4ConstArg aabbMax1,
								  b3Float4ConstArg aabbMin2, b3Float4ConstArg aabbMax2)
{
	bool overlap = true;
	overlap = (aabbMin1.x > aabbMax2.x || aabbMax1.x < aabbMin2.x) ? false : overlap;
	overlap = (aabbMin1.z > aabbMax2.z || aabbMax1.z < aabbMin2.z) ? false : overlap;
	overlap = (aabbMin1.y > aabbMax2.y || aabbMax1.y < aabbMin2.y) ? false : overlap;
	return overlap;
}

#endif  //B3_AABB_H