public void TestConstructor()
{
var pA = new Particle {
Mass = 1
};
var pB = new Particle {
Mass = 1
};
var rope = new ParticleRope(10, 0.5, pA, pB);
Assert.AreEqual(10, rope.MaxLength);
Assert.AreEqual(pA, rope.ParticleA);
Assert.AreEqual(pB, rope.ParticleB);
Assert.AreEqual(0.5, rope.Restitution);
}
public void TestGetEnumerator()
{
var pA = new Particle {
Mass = 1
};
var pB = new Particle {
Mass = 1
};
var rope = new ParticleRope(10, 0.5, pA, pB);
var contacts = new List <ParticleContact>();
contacts.AddRange(rope);
Assert.AreEqual(0, contacts.Count, "长度未变化时不产生任何碰撞");
pB.Position = new Vector2D(20, 0);
foreach (var contact in rope)
{
Assert.AreEqual(10, contact.Penetration);
Assert.AreEqual(new Vector2D(1, 0), contact.ContactNormal);
}
}
/// <summary>
/// 在物理世界创建一条质体绳索
/// 该绳索由两个质体（质点）组成，两个质体的距离被限定在指定的数值内
/// </summary>
/// <param name="world"></param>
/// <param name="maxLength"></param>
/// <param name="restitution"></param>
/// <param name="a"></param>
/// <param name="b"></param>
/// <returns></returns>
public static ParticleRope CreateRope(this World world, double maxLength, double restitution, Particle a, Particle b)
{
var rope = new ParticleRope(maxLength, restitution, a, b);
return(world.CreateContact(rope));
}
