/// <summary>
/// 获取反射点坐标及碰撞线段
/// </summary>
/// <param name="seg"></param>
/// <returns></returns>
public Point? GetClosestReflectionPoint(LineSegment seg, out LineSegment collision_seg)
{
if (!this.BorderRect.IntersectsWith(new Rectangle(seg.Left, seg.Top, seg.Right - seg.Left, seg.Bottom - seg.Top))) //先用矩形进行快速判断
{
collision_seg = null;
return null;
}
Dictionary<Point?, int> pt_idx_dict = new Dictionary<Point?, int>();
for (int i = 0; i < this.border_segments.Length; i++)
{
Point? pt = seg.GetIntersectionPoint(this.border_segments[i]);
if (pt != null && !pt_idx_dict.Keys.Contains(pt))
pt_idx_dict.Add(pt, i);
}
if(pt_idx_dict.Count == 0) //没有交点
{
collision_seg = null;
return null;
}
KeyValuePair<Point?, int> pt_idx = new KeyValuePair<Point?, int>();
double min_d2 = double.PositiveInfinity;
foreach(KeyValuePair<Point?, int> kvp in pt_idx_dict)
{
double dist2 = Math.Pow(kvp.Key.Value.X - seg.TailPosition.X, 2) + Math.Pow(kvp.Key.Value.Y - seg.TailPosition.Y, 2);
if(dist2 > 0 && dist2 < min_d2)
{
min_d2 = dist2;
pt_idx = kvp;
}
}
collision_seg = this.border_segments[pt_idx.Value];
return pt_idx.Key;
}
/// <summary>
/// 线段类的单元测试
/// </summary>
/// <param name="epsilon"></param>
/// <returns></returns>
public static string RunTest(double epsilon=1e-3)
{
LineSegment This = new LineSegment();
LineSegment That = new LineSegment();
DateTime time = DateTime.Now;
StringBuilder sb = new StringBuilder("LineSegment Class Test Begin at " + time.ToString("yyyy-MM-dd HH:mm:ss") + "\n");
test_log.Add(time, "");
//test Length
sb.AppendLine("----------------------------");
sb.AppendLine("length test 1");
Debug.Assert(new LineSegment(new Point(0, 0), new Point(0, 0)).Length == 0, "length should be 0");
sb.AppendLine("length test 2");
Debug.Assert(new LineSegment(new Point(0, 1), new Point(1, 0)).Length == Math.Sqrt(2), "length should be sqrt(2)");
sb.AppendLine("length test 3");
Debug.Assert(new LineSegment(new Point(2, 0), new Point(0, 0)).Length == 2, "length should be 2");
sb.AppendLine("length test 4");
Debug.Assert(new LineSegment(new Point(0, 0), new Point(0, 2)).Length == 2, "length should be 2");
//test DirectionRadius
sb.AppendLine("----------------------------");
sb.AppendLine("direction test 1");
Debug.Assert(new LineSegment(new Point(0, 0), new Point(0, 0)).DirectionRadian == 0, "direction should be 0");
sb.AppendLine("direction test 2");
Debug.Assert(new LineSegment(new Point(1, 0), new Point(0, 0)).DirectionRadian == 0, "direction should be 0");
sb.AppendLine("direction test 3");
Debug.Assert(new LineSegment(new Point(0, 0), new Point(0, 1)).DirectionRadian == Math.PI / 2, "direction should be pi/2");
sb.AppendLine("direction test 4");
Debug.Assert(new LineSegment(new Point(0, 0), new Point(1, 0)).DirectionRadian == Math.PI, "direction should be pi");
sb.AppendLine("direction test 5");
Debug.Assert(new LineSegment(new Point(0, 1), new Point(0, 0)).DirectionRadian == Math.PI / 2 * 3, "direction should be pi/2*3");
sb.AppendLine("direction test 6");
Debug.Assert(new LineSegment(new Point(1, 0), new Point(0, 1)).DirectionRadian == Math.PI / 4, "direction should be pi/4");
sb.AppendLine("direction test 7");
Debug.Assert(new LineSegment(new Point(0, 0), new Point(1, 1)).DirectionRadian == Math.PI / 4 * 3, "direction should be pi/4*3");
sb.AppendLine("direction test 8");
Debug.Assert(new LineSegment(new Point(0, 1), new Point(1, 0)).DirectionRadian == Math.PI / 4 * 5, "direction should be pi/4*5");
sb.AppendLine("direction test 9");
Debug.Assert(new LineSegment(new Point(1, 1), new Point(0, 0)).DirectionRadian == Math.PI / 4 * 7, "direction should be pi/4*7");
//test Angle
sb.AppendLine("----------------------------");
This = new LineSegment(new Point(1, 0), new Point(0, 0));
sb.AppendLine("angle test 1");
That = new LineSegment(new Point(1, 0), new Point(0, 0));
Debug.Assert(This.Angle(That) == 0, "angle should be 0");
sb.AppendLine("angle test 2");
That = new LineSegment(new Point(0, 0), new Point(0, 1));
Debug.Assert(This.Angle(That) == Math.PI / 2, "angle should be pi/2");
sb.AppendLine("angle test 3");
That = new LineSegment(new Point(0, 0), new Point(1, 0));
Debug.Assert(This.Angle(That) == Math.PI, "angle should be pi");
sb.AppendLine("angle test 4");
That = new LineSegment(new Point(0, 1), new Point(0, 0));
Debug.Assert(This.Angle(That) == Math.PI / 2, "angle should be pi/2");
sb.AppendLine("angle test 5");
That = new LineSegment(new Point(1, 0), new Point(0, 1));
Debug.Assert(This.Angle(That) > Math.PI / 4 - epsilon && This.Angle(That) < Math.PI / 4 + epsilon, "angle should be pi/4");
sb.AppendLine("angle test 6");
Debug.Assert(new LineSegment(new Point(1, 0), new Point(0, 0)).Angle(new LineSegment(new Point(0, 0), new Point(1, 1))) == Math.PI / 4 * 3, "angle should be pi/4*3");
sb.AppendLine("angle test 7");
Debug.Assert(new LineSegment(new Point(1, 0), new Point(0, 0)).Angle(new LineSegment(new Point(0, 1), new Point(1, 0))) == Math.PI / 4 * 3, "angle should be pi/4*3");
sb.AppendLine("angle test 8");
That = new LineSegment(new Point(1, 1), new Point(0, 0));
Debug.Assert(This.Angle(That) > Math.PI / 4 - epsilon && This.Angle(That) < Math.PI / 4 + epsilon, "angle should be pi/4");
sb.AppendLine("angle test 9");
That = new LineSegment(new Point(0, 0), new Point(0, 0));
Debug.Assert(This.Angle(That) == 0, "angle should be 0");
//test JudgeIntersection
sb.AppendLine("----------------------------");
This = new LineSegment(new Point(2, 2), new Point(0, 2));
sb.AppendLine("intersection test 1");
That = new LineSegment(new Point(1, 2), new Point(0, 2));
Debug.Assert(This.JudgeIntersection(That) == false, "intersection should be false");
sb.AppendLine("intersection test 2");
That = new LineSegment(new Point(1, 1), new Point(0, 1));
Debug.Assert(This.JudgeIntersection(That) == false, "intersection should be false");
sb.AppendLine("intersection test 3");
That = new LineSegment(new Point(0, 1), new Point(1, 1));
Debug.Assert(This.JudgeIntersection(That) == false, "intersection should be false");
sb.AppendLine("intersection test 4");
That = new LineSegment(new Point(1, 0), new Point(1, 1));
Debug.Assert(This.JudgeIntersection(That) == false, "intersection should be false");
sb.AppendLine("intersection test 5");
That = new LineSegment(new Point(1, 1), new Point(1, 0));
Debug.Assert(This.JudgeIntersection(That) == false, "intersection should be false");
sb.AppendLine("intersection test 6");
That = new LineSegment(new Point(1, 1), new Point(0, 2));
Debug.Assert(This.JudgeIntersection(That) == true, "intersection should be true");
sb.AppendLine("intersection test 7");
That = new LineSegment(new Point(1, 1), new Point(2, 2));
Debug.Assert(This.JudgeIntersection(That) == true, "intersection should be true");
sb.AppendLine("intersection test 8");
That = new LineSegment(new Point(3, 1), new Point(2, 2));
Debug.Assert(This.JudgeIntersection(That) == true, "intersection should be true");
sb.AppendLine("intersection test 9");
That = new LineSegment(new Point(2, 1), new Point(1, 2));
Debug.Assert(This.JudgeIntersection(That) == true, "intersection should be true");
sb.AppendLine("intersection test 10");
That = new LineSegment(new Point(1, 2), new Point(2, 3));
Debug.Assert(This.JudgeIntersection(That) == true, "intersection should be true");
sb.AppendLine("intersection test 11");
That = new LineSegment(new Point(0, 0), new Point(2, 3));
Debug.Assert(This.JudgeIntersection(That) == true, "intersection should be true");
sb.AppendLine("intersection test 12");
That = new LineSegment(new Point(1, 0), new Point(0, 3));
Debug.Assert(This.JudgeIntersection(That) == true, "intersection should be true");
sb.AppendLine("intersection test 13");
That = new LineSegment(new Point(1, 3), new Point(1, 1));
Debug.Assert(This.JudgeIntersection(That) == true, "intersection should be true");
sb.AppendLine("intersection test 14");
That = new LineSegment(new Point(3, 2), new Point(2, 2));
Debug.Assert(This.JudgeIntersection(That) == false, "intersection should be false");
sb.AppendLine("intersection test 15");
That = new LineSegment(new Point(1, 2), new Point(1, 2));
Debug.Assert(This.JudgeIntersection(That) == false, "intersection should be false");
//test GetIntersectionPoint
sb.AppendLine("----------------------------");
This = new LineSegment(new Point(3, 2), new Point(1, 2));
sb.AppendLine("intersection point test 1");
That = new LineSegment(new Point(3, 1), new Point(1, 1));
Debug.Assert(This.GetIntersectionPoint(That) == null, "intersection point should be null");
sb.AppendLine("intersection point test 2");
That = new LineSegment(new Point(4, 1), new Point(3, 2));
Debug.Assert(This.GetIntersectionPoint(That) == new Point(3, 2), "intersection point should be (3, 2)");
sb.AppendLine("intersection point test 3");
That = new LineSegment(new Point(3, 1), new Point(3, 2));
Debug.Assert(This.GetIntersectionPoint(That) == new Point(3, 2), "intersection point should be (3, 2)");
sb.AppendLine("intersection point test 4");
That = new LineSegment(new Point(2, 1), new Point(3, 2));
Debug.Assert(This.GetIntersectionPoint(That) == new Point(3, 2), "intersection point should be (3, 2)");
sb.AppendLine("intersection point test 5");
That = new LineSegment(new Point(3, 2), new Point(2, 3));
Debug.Assert(This.GetIntersectionPoint(That) == new Point(3, 2), "intersection point should be (3, 2)");
sb.AppendLine("intersection point test 6");
That = new LineSegment(new Point(3, 2), new Point(4, 3));
Debug.Assert(This.GetIntersectionPoint(That) == new Point(3, 2), "intersection point should be (3, 2)");
sb.AppendLine("intersection point test 7");
That = new LineSegment(new Point(2, 1), new Point(2, 3));
Debug.Assert(This.GetIntersectionPoint(That) == new Point(2, 2), "intersection point should be (2, 2)");
sb.AppendLine("intersection point test 8");
That = new LineSegment(new Point(1, 1), new Point(3, 3));
Debug.Assert(This.GetIntersectionPoint(That) == new Point(2, 2), "intersection point should be (2, 2)");
sb.AppendLine("intersection point test 9");
That = new LineSegment(new Point(3, 3), new Point(1, 1));
Debug.Assert(This.GetIntersectionPoint(That) == new Point(2, 2), "intersection point should be (2, 2)");
sb.AppendLine("intersection point test 10");
That = new LineSegment(new Point(3, 1), new Point(1, 3));
Debug.Assert(This.GetIntersectionPoint(That) == new Point(2, 2), "intersection point should be (2, 2)");
sb.AppendLine("intersection point test 11");
That = new LineSegment(new Point(1, 3), new Point(3, 1));
Debug.Assert(This.GetIntersectionPoint(That) == new Point(2, 2), "intersection point should be (2, 2)");
sb.AppendLine("intersection point test 12");
That = new LineSegment(new Point(2, 3), new Point(0, 1));
Debug.Assert(This.GetIntersectionPoint(That) == new Point(1, 2), "intersection point should be (1, 2)");
sb.AppendLine("intersection point test 13");
That = new LineSegment(new Point(2, 2), new Point(2, 2));
Debug.Assert(This.GetIntersectionPoint(That) == null, "intersection point should be null");
test_log[time] = sb.ToString();
return test_log[time];
}
