public Scatter(LineSegment[] segs, SCATTER_SEG_DIRECTION direction=SCATTER_SEG_DIRECTION.CLOCKWISE, double dc=2, string name="")
{
if (!IsSegmentsLegal(segs))
throw new Exception("线段集合不符合要求，请保证：\n" +
"1. 至少有3条线段\n" +
"2. 集合内的线段按序首尾相连\n" +
"3. 每条线段都不与除相临线段外的任何线段相交\n");
this.border_segments = segs;
this.seg_direction = direction;
this.dielectric_constant = dc;
int top = int.MaxValue, bottom = int.MinValue, left = int.MaxValue, right = int.MinValue;
foreach(LineSegment seg in segs)
{
if (seg.Top < top)
top = seg.Top;
if (seg.Bottom > bottom)
bottom = seg.Bottom;
if (seg.Left < left)
left = seg.Left;
if (seg.Right > right)
right = seg.Right;
}
this.border_rect.X = left;
this.border_rect.Y = top;
this.border_rect.Width = right - left;
this.border_rect.Height = bottom - top;
this.name = name == "" ? "Scatter" + id.ToString() : name;
id++;
}
///// <summary>
///// 自由空间路径损耗
///// </summary>
///// <param name="Pi"></param>
///// <param name="d"></param>
///// <param name="freq"></param>
///// <returns></returns>
//public static double FreeSpacePathLoss(double Pi, double d, double freq)
//{
// double dbi = 20 * Math.Log10(freq / 1e6) + 20 * Math.Log10(d / 1e3);
// double ratio = Math.Pow(10, (dbi / 10));
// return Pi / ratio;
//}
/// <summary>
/// 计算镜面反射角
/// </summary>
/// <param name="ray">入射波束线段</param>
/// <param name="barrier">产生碰撞的散射体线段</param>
/// <param name="dir">散射体的向量旋转方向</param>
/// /// <returns>出射角</returns>
public static double SpecularReflection(LineSegment ray, LineSegment barrier, SCATTER_SEG_DIRECTION dir)
{
double result;
double angle = ray.Angle(barrier);
if(dir == SCATTER_SEG_DIRECTION.CLOCKWISE)
{
result = barrier.DirectionRadian + angle;
result = result > Math.PI * 2 ? result - Math.PI * 2 : result;
}
else
{
result = barrier.DirectionRadian - angle;
result = result < 0 ? result + Math.PI * 2 : result;
}
return result;
}
public Scatter(Point[] vertices, SCATTER_SEG_DIRECTION direction=SCATTER_SEG_DIRECTION.CLOCKWISE, double dc=2, string name="")
{
Exception ex = new Exception("顶点集合不符合要求，请保证：\n" +
"1. 至少有3个顶点\n" +
"2. 顶点按序连成的每条线段都不与除相临线段外的任何线段相交\n");
if (vertices.Length < 3)
throw ex;
List<LineSegment> segs = new List<LineSegment>();
for(int i = 1; i < vertices.Length; i++)
{
segs.Add(new LineSegment(vertices[i - 1], vertices[i]));
}
segs.Add(new LineSegment(vertices[vertices.Length - 1], vertices[0]));
LineSegment[] sgs = segs.ToArray();
if (!IsSegmentsLegal(sgs))
throw ex;
this.border_segments = sgs;
this.seg_direction = direction;
this.dielectric_constant = dc;
int top = int.MaxValue, bottom = int.MinValue, left = int.MaxValue, right = int.MinValue;
foreach (LineSegment seg in segs)
{
if (seg.Top < top)
top = seg.Top;
if (seg.Bottom > bottom)
bottom = seg.Bottom;
if (seg.Left < left)
left = seg.Left;
if (seg.Right > right)
right = seg.Right;
}
this.border_rect.X = left;
this.border_rect.Y = top;
this.border_rect.Width = right - left;
this.border_rect.Height = bottom - top;
this.name = name == "" ? "Scatter" + id.ToString() : name;
id++;
}
/// <summary>
/// 获取反射点坐标及碰撞线段和碰撞散射体的旋转方向
/// </summary>
/// <param name="seg"></param>
/// <param name="collision_seg"></param>
/// <param name="dir"></param>
/// <returns></returns>
public Point? GetClosestReflectionPoint(LineSegment seg, out LineSegment collision_seg, out SCATTER_SEG_DIRECTION dir, out double dc)
{
Dictionary<Point?, object[]> pt_seg_dir_dict = new Dictionary<Point?, object[]>();
foreach (Scatter scatter in this.Scatters)
{
Point? tmp_pt = null;
LineSegment tmp_seg = null;
SCATTER_SEG_DIRECTION tmp_dir = scatter.SegDirection;
double tmp_dc = scatter.DielectricConstant;
tmp_pt = scatter.GetClosestReflectionPoint(seg, out tmp_seg);
if (tmp_pt != null)
pt_seg_dir_dict.Add(tmp_pt, new object[] { tmp_seg, tmp_dir, tmp_dc });
}
if(pt_seg_dir_dict.Count == 0) //没有交点
{
collision_seg = null;
dir = SCATTER_SEG_DIRECTION.CLOCKWISE;
dc = 0;
return null;
}
KeyValuePair<Point?, object[]> tmp_kvp = pt_seg_dir_dict.First();
double min_d2 = double.PositiveInfinity;
foreach (KeyValuePair<Point?, object[]> kvp in pt_seg_dir_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;
tmp_kvp = kvp;
}
}
collision_seg = tmp_kvp.Value[0] as LineSegment;
dir = (SCATTER_SEG_DIRECTION)tmp_kvp.Value[1];
dc = (double)tmp_kvp.Value[2];
return tmp_kvp.Key;
}
