opc_sphereaabboverlap.h

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///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
/**
 *	Sphere-AABB overlap test, based on Jim Arvo's code.
 *	\param		center_		[in] box center
 *	\param		extents_		[in] box extents
 *	\return		TRUE on overlap
 */
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
inline_ BOOL SphereCollider::SphereAABBOverlap(const IceMaths::Point& center_, const IceMaths::Point& extents_)
{ 
	// Stats
	mNbVolumeBVTests++;

	// Applies the model's local scale
	const IceMaths::Point  center = center_ *mLocalScale;
	const IceMaths::Point extents = extents_*mLocalScale;

	float d = 0.0f;

	//find the square of the distance
	//from the sphere to the box
#ifdef OLDIES
	for(udword i=0;i<3;i++)
	{
		float tmp = mCenter[i] - center[i];
		float s = tmp + extents[i];

		if(s<0.0f)	d += s*s;
		else
		{
			s = tmp - extents[i];
			if(s>0.0f)	d += s*s;
		}
	}
#endif

//#ifdef NEW_TEST

//	float tmp = mCenter.x - center.x;
//	float s = tmp + extents.x;

	float tmp,s;

	tmp = mCenter.x - center.x;
	s = tmp + extents.x;

	if(s<0.0f)
	{
		d += s*s;
		if(d>mRadius2)	return FALSE;
	}
	else
	{
		s = tmp - extents.x;
		if(s>0.0f)
		{
			d += s*s;
			if(d>mRadius2)	return FALSE;
		}
	}

	tmp = mCenter.y - center.y;
	s = tmp + extents.y;

	if(s<0.0f)
	{
		d += s*s;
		if(d>mRadius2)	return FALSE;
	}
	else
	{
		s = tmp - extents.y;
		if(s>0.0f)
		{
			d += s*s;
			if(d>mRadius2)	return FALSE;
		}
	}

	tmp = mCenter.z - center.z;
	s = tmp + extents.z;

	if(s<0.0f)
	{
		d += s*s;
		if(d>mRadius2)	return FALSE;
	}
	else
	{
		s = tmp - extents.z;
		if(s>0.0f)
		{
			d += s*s;
			if(d>mRadius2)	return FALSE;
		}
	}
//#endif

#ifdef OLDIES
//	Point Min = center - extents;
//	Point Max = center + extents;

	float d = 0.0f;

	//find the square of the distance
	//from the sphere to the box
	for(udword i=0;i<3;i++)
	{
float Min = center[i] - extents[i];

//		if(mCenter[i]<Min[i])
		if(mCenter[i]<Min)
		{
//			float s = mCenter[i] - Min[i];
			float s = mCenter[i] - Min;
			d += s*s;
		}
		else
		{
float Max = center[i] + extents[i];

//			if(mCenter[i]>Max[i])
			if(mCenter[i]>Max)
			{
				float s = mCenter[i] - Max;
				d += s*s;
			}
		}
	}
#endif
	return d <= mRadius2;
}