/// <summary>
/// GJK算法的多边形碰撞检测
/// </summary>
/// <param name="a">形状a</param>
/// <param name="b">形状b</param>
/// <returns>是否碰撞</returns>
public static bool GJKCheck(ShapBase a, ShapBase b)
{
Fixed2 direction = a.position - b.position;
Simplex s = new Simplex();
s.Push(ShapBase.Support(a, b, direction));
direction = -direction;
while (true) //迭代
{
s.Push(ShapBase.Support(a, b, direction));
if (s.GetA().Dot(direction) < 0)
{
return(false);
}
else
{
if (s.ContainsOrigin())
{
return(true);
}
else
{
direction = s.GetDirection();
}
}
}
}
/// <summary>
/// 给定方向 给定两个凸体 该函数返回这两个凸体明可夫斯基差形状中的一个点
/// </summary>
/// <param name="a">形状a</param>
/// <param name="b">形状b</param>
/// <param name="direction">迭代方向</param>
/// <returns>指定方向内的一点</returns>
public static Fixed2 Support(ShapBase a, ShapBase b, Fixed2 direction)
{
Fixed2 p1 = a.Support(direction);
Fixed2 p2 = b.Support(-direction);
//Debug.Log("Support{ p1:" + p1 + "p2:" + p2 + "p3:" + (p1 - p2));
return(p1 - p2);
}
public static void Draw(ShapBase shap, Color color, float time = 0.1f)
{
for (int i = 0; i < shap.PointsCount - 1; i++)
{
UnityEngine.Debug.DrawLine((shap.position + shap.GetPoint(i)).ToVector3(), (shap.position + shap.GetPoint(i + 1)).ToVector3(), color, time);
}
UnityEngine.Debug.DrawLine((shap.position + shap.GetPoint(shap.PointsCount - 1)).ToVector3(), (shap.position + shap.GetPoint(0)).ToVector3(), color, time);
}
public List <Tree4> GetInTrees(ShapBase shap)
{
List <Tree4> treeList = new List <Tree4>();
foreach (var t in trees)
{
treeList.AddRange(t.GetInTress(shap));
}
return(treeList);
}
public void SetShap(Vector2[] points)
{
var ps = new Fixed2[points.Length];
for (int i = 0; i < ps.Length; i++)
{
ps[i] = points[i].ToFixed2();
}
Shap = new ShapBase(ps);
}
public static bool BoxCheck(ShapBase objA, ShapBase objB)
{
if (FixedNumber.Abs((objA.position.x - objB.position.x)) < (objA.width + objB.width) / 2
&&
FixedNumber.Abs((objA.position.y - objB.position.y)) < (objA.height + objB.height) / 2
)
{
return(true);
}
return(false);
}
public bool IsIn(ShapBase shap)
{
if (((border.center.x - shap.position.x).Abs() <= (border.size + shap.width / 2))
&&
((border.center.y - shap.position.y).Abs() <= (border.size + shap.height / 2))
)
{
return(true);
}
return(false);
}
public List <Tree4> GetInTress(ShapBase shap)
{
List <Tree4> treeList = new List <Tree4>();
if (child == null)
{
if (IsIn(shap))
{
treeList.Add(this);
}
}
else
{
treeList.AddRange(child.GetInTrees(shap));
}
return(treeList);
}
public List <NetData> CheckShap(ShapBase shap)
{
List <NetData> objs = new List <NetData>();
var treeList = GetInTress(shap);
foreach (var tree in treeList)
{
for (int i = 0; i < tree.objs.Count; i++)
{
if (ShapPhysics.Check(shap, tree.objs[i].Shap))
{
objs.Add(tree.objs[i]);
}
}
}
return(objs);
}
public List <NetData> CheckShap(ShapBase shap)
{
List <NetData> objs = new List <NetData>();
var treeList = GetInTress(shap);
foreach (var tree in treeList)
{
for (int i = 0; i < tree.objs.Count; i++)
{
if (!tree.objs[i].isTrigger && ShapPhysics.Check(shap, tree.objs[i].Shap))
{
//当物体处于四叉树交界处 可能会添加多次
if (!objs.Contains(tree.objs[i]))
{
objs.Add(tree.objs[i]);
}
}
}
}
return(objs);
}
public List <NetData> OverlapShap(ShapBase shap)
{
return(tree.CheckShap(shap));
}
public List <NetData> OverlapShap(ShapBase shap, Fixed2 position)
{
shap.position = position;
return(OverlapShap(shap));
}
//GJK算法原理
//两个物体进行明可夫斯基差操作 得到的新图形形状包含原点则这两个图形的是相交的
/// <summary>
/// 立即检测两个物体是否发生细节碰撞
/// 先包围盒检测（粗略） 后GJK碰撞检测（细节）
/// </summary>
/// <param name="a">检测对象a</param>
/// <param name="b">检测对象b</param>
/// <returns>是否碰撞</returns>
public static bool Check(ShapBase a, ShapBase b)
{
return(BoxCheck(a, b) && GJKCheck(a, b));//;// xB&&yB;
}
public List <NetData> OverlapShap(ShapBase shap)
{
ShapDebug.Draw(shap, UnityEngine.Color.red);
return(tree.CheckShap(shap));
}