public Vector3 GetSteering(ICollection <Rigidbody> targets)
{
Vector3 acceleration = Vector3.zero;
// 只要存在发生碰撞的就要想办法分离
foreach (Rigidbody r in targets)
{
/* 远离的方向 */
Vector3 direction = transform.position - r.position;
float dist = direction.magnitude;
if (dist < maxSepDist)
{
float targetRadius = SteeringBasics.GetBoundingRadius(r.transform);
/* 计算分离强度(可改为使用平方反比，而不是线性) */
var strength = sepMaxAcceleration * (maxSepDist - dist) / (maxSepDist - boundingRadius - targetRadius);
/* 将分离加速度增加到现有的 Steer 上 （因为可能不是跟一个发生碰撞） */
direction.Normalize();
acceleration += direction * strength;
}
}
return(acceleration);
}
void Start()
{
// 得到屏幕大小
float z = -1 * Camera.main.transform.position.z;
bottomLeft = Camera.main.ViewportToWorldPoint(new Vector3(0, 0, z));
Vector3 topRight = Camera.main.ViewportToWorldPoint(new Vector3(1, 1, z));
widthHeight = topRight - bottomLeft;
// 如果需要的话 要避免和场景内其他对象重叠 纪录他们的数据
thingsToAvoidRadius = new float[thingsToAvoid.Length];
for (int i = 0; i < thingsToAvoid.Length; i++)
{
thingsToAvoidRadius[i] = SteeringBasics.GetBoundingRadius(thingsToAvoid[i].transform);
}
// 创建就行了
for (int i = 0; i < numberOfObjects; i++)
{
// 每次不一定创建成功，这里增加概率
for (int j = 0; j < 10; j++)
{
if (TryToCreateObject())
{
break;
}
}
}
}
/// <summary>
/// 判断是否可以放置， 主要判断是否重叠
/// </summary>
/// <param name="halfSize"></param>
/// <param name="pos"></param>
/// <returns></returns>
private bool CanPlaceObject(float halfSize, Vector3 pos)
{
// 确保它不会与任何东西重叠
for (int i = 0; i < thingsToAvoid.Length; i++)
{
float dist = Vector3.Distance(thingsToAvoid[i].position, pos);
if (dist < halfSize + thingsToAvoidRadius[i])
{
return(false);
}
}
//确保它不会与任何现有对象重叠
foreach (Rigidbody o in objs)
{
float dist = Vector3.Distance(o.position, pos);
float oRadius = SteeringBasics.GetBoundingRadius(o.transform);
if (dist < oRadius + spaceBetweenObjects + halfSize)
{
return(false);
}
}
return(true);
}
// 获取隐藏位置
private Vector3 GetHidingPosition(Rigidbody obstacle, Rigidbody target)
{
// 这个障碍物 附近
float distAway = SteeringBasics.GetBoundingRadius(obstacle.transform) + distanceFromBoundary;
// 目标看障碍物的方向（就要躲在这个方向上）
Vector3 dir = obstacle.position - target.position;
dir.Normalize();
// 最终隐藏位置
return(obstacle.position + dir * distAway);
}
public Vector3 GetSteering(ICollection <Rigidbody> targets)
{
Vector3 acceleration = Vector3.zero;
/* 1. 找出这个角色将会与之碰撞的第一个目标 */
/* 第一次碰撞时间 */
float shortestTime = float.PositiveInfinity; // 正无穷大 临时值
/* The first target that will collide and other data that
* we will need and can avoid recalculating */
// 重置数据 ，并且可以避免重新计算
Rigidbody firstTarget = null;
//float firstMinSeparation = 0, firstDistance = 0;
float firstMinSeparation = 0,
firstDistance = 0,
firstRadius = 0;
Vector3 firstRelativePos = Vector3.zero,
firstRelativeVel = Vector3.zero;
foreach (Rigidbody r in targets)
{
/* 计算碰撞时间 */
// 相差位置
Vector3 relativePos = transform.position - r.position;
// 相差速度
Vector3 relativeVel = rb.velocity - r.velocity;
// 标量
float distance = relativePos.magnitude;
float relativeSpeed = relativeVel.magnitude;
// 说明朝着相反的方向运动 并且速度一样
if (relativeSpeed == 0)
{
continue;
}
//
float timeToCollision = -1 * Vector3.Dot(relativePos, relativeVel) / (relativeSpeed * relativeSpeed);
/* 检查它们是否会碰撞 */
Vector3 separation = relativePos + relativeVel * timeToCollision;
float minSeparation = separation.magnitude;
float targetRadius = SteeringBasics.GetBoundingRadius(r.transform);
// 两者分离了
if (minSeparation > characterRadius + targetRadius)
//if (minSeparation > 2 * agentRadius)
{
continue;
}
/* 检查它是否是最短， 是的话就纪录最短的 */
if (timeToCollision > 0 && timeToCollision < shortestTime)
{
shortestTime = timeToCollision;
firstTarget = r;
firstMinSeparation = minSeparation;
firstDistance = distance;
firstRelativePos = relativePos;
firstRelativeVel = relativeVel;
firstRadius = targetRadius;
}
}
/* 2. 计算加速度 */
/* 如果没有目标，就退出 */
if (firstTarget == null)
{
return(acceleration);
}
/* If we are going to collide with no separation or if we are already colliding then
* Steer based on current position */
// 如果我们要在没有分离的情况下发生碰撞，或者如果我们已经碰撞了，然后根据当前位置进行碰撞
if (firstMinSeparation <= 0 || firstDistance < characterRadius + firstRadius)
//if (firstMinSeparation <= 0 || firstDistance < 2 * agentRadius)
{
acceleration = transform.position - firstTarget.position;
}
/* 计算未来的相对位置 */
else
{
acceleration = firstRelativePos + firstRelativeVel * shortestTime;
}
/* 远离目标 */
acceleration.Normalize();
acceleration *= maxAcceleration;
return(acceleration);
}
void Start()
{
characterRadius = SteeringBasics.GetBoundingRadius(transform);
rb = GetComponent <Rigidbody>();
}
// Use this for initialization
void Start()
{
boundingRadius = SteeringBasics.GetBoundingRadius(transform);
}