/// <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);
}