/********************************************************************************

** All rights reserved

** Auth： kay.yang

** Date： 6/12/2017 9:12:46 AM

** Version: v1.0.0

*********************************************************************************/

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using UnityEngine;

namespace BVH

{

public class BVHSphereObject : BVHObject

{

public Vector3 mCenter;

public float mRadius, mRadius2; // Radius, Radius^2

public BVHSphereObject(Vector3 center, float r)

{

mCenter = center;

mRadius = r;

mRadius2 = mRadius * mRadius;

}

override

public bool GetIntersection(ref BVHRay ray, ref BVHIntersectionInfo intersection)

{

Vector3 s = mCenter - ray.mOrigin;

float sd = Vector3.Dot(s, ray.mDirection);

float ss = s.magnitude * s.magnitude;

float disc = sd * sd + mRadius2 - ss;

if (disc < 0.0f)

{

return false;

}

intersection.mObject = this;

intersection.mLength = sd - Mathf.Sqrt(disc);

return true;

}

override

public Vector3 GetNormal(ref BVHIntersectionInfo i)

{

Vector3 nor = i.mHitPoint - mCenter;

nor.Normalize();

return nor;

}

override

public BVHBox GetBBox()

{

return new BVHBox(mCenter - new Vector3(mRadius, mRadius, mRadius), mCenter + new Vector3(mRadius, mRadius, mRadius)); ;

}

override

public Vector3 GetCentroid()

{

return mCenter;

}

}

}