/// <summary>
/// 合并可以合并的线段
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void MergeTestBtn_Click(object sender, RoutedEventArgs e)
{
List <Geometry2D> gss = this.drawingKernel.GeometryShapes;
List <Line2D> lines = new List <Line2D>();
foreach (var g in gss)
{
if (g is DrawingKernel.Geometries.Primitives.LineGeometry)
{
DrawingKernel.Geometries.Primitives.LineGeometry line = g as DrawingKernel.Geometries.Primitives.LineGeometry;
lines.Add(Line2D.Create(line.Start, line.End));
}
if (g.GeometryId == "tp")
{
this.drawingKernel.RemoveGeometryShape(g);
}
}
List <Line2D> mergeLines = GraphicAlgorithm.Merge(lines);
if (mergeLines != null)
{
mergeLines.ForEach(x =>
{
DrawingKernel.Geometries.Primitives.LineGeometry lg = new DrawingKernel.Geometries.Primitives.LineGeometry(x.Start, x.End);
lg.PenColor = KernelProperty.GetRandomColor();
lg.GeometryId = "tp";
this.drawingKernel.AddShape(lg);
});
}
}
/// <summary>
/// 对多边形进行扩张和缩放，range为负数为内缩小，为正数为外扩
/// </summary>
/// <param name="lines"></param>
/// <param name="range"></param>
/// <returns></returns>
public List <Line2D> Elastic(List <Line2D> lines, double range, List <Line2D> neverOffset, bool allowDistortion = false)
{
if (range < 0)
{
//说明会引起多边形形状的变化
Line2D line = lines.Find(x => x.Length < Math.Abs(range));
//说明图形已经边型了，需要变形处理
if (line != null && allowDistortion)
{
//允许变形的缩放
this.ElasticDistortion(lines, range);
}
}
List <Line2D> NLList = new List <Line2D>();
//首先需要对线段进行一次合并，由于多边形可能存在共线的情况，那么偏移会出问题
var mergelines = GraphicAlgorithm.Merge(lines);
//获取当前线段的顺时针排序
List <Line2D> sortLines = GraphicAlgorithm.Sort(mergelines, null, 1);
//获取当前连续的顶点
List <Vector2D> PList = new List <Vector2D>();
//当前直线的方向
List <Vector2D> DList = new List <Vector2D>();
//记录所有的点
sortLines.ForEach(x => {
PList.Add(x.Start);
DList.Add(x.Direction);
});
//所有点的列表
List <Vector2D> NPList = new List <Vector2D>();
int startIndex, endindex;
//获取所有的点
for (int i = 0; i < DList.Count; i++)
{
startIndex = i == 0 ? DList.Count - 1 : i - 1;
endindex = i;
//两个线之间的夹角
double sina = DList[startIndex].Cross(DList[endindex]);
//用于判断当前是阴阳角
var Corndir = 0;
if (sina > 0)
{
Corndir = 1;
}
else
{
Corndir = -1;
}
//由于偏移出是平行四边形，则要移动的长度为
var moveLen = -range / sina;
Vector2D movedir = null;
if (neverOffset != null)
{
var nf = neverOffset.FindAll(x => x.Start.IsAlmostEqualTo(PList[i]) || x.End.IsAlmostEqualTo(PList[i]));
if (nf != null && nf.Count == 1)
{
if (nf[0].Direction.IsAlmostEqualTo(DList[startIndex]) || nf[0].Direction.IsAlmostEqualTo(-DList[startIndex]))
{
movedir = DList[startIndex];
Vector2D npt = PList[i] + movedir * range * Corndir;
NPList.Add(npt);
}
else
{
movedir = -DList[endindex];
Vector2D npt = PList[i] + movedir * range * Corndir;
NPList.Add(npt);
}
continue;
}
if (nf != null && nf.Count == 2)
{
NPList.Add(PList[i]);
continue;
}
}
//移动的方向为
movedir = DList[endindex] - DList[startIndex];
Vector2D np = PList[i] + movedir * moveLen;
//添加新点
NPList.Add(np);
}
///形成新的线
for (int i = 0; i < NPList.Count; i++)
{
var index = i == (NPList.Count - 1) ? 0 : i + 1;
NLList.Add(Line2D.Create(NPList[i], NPList[index]));
}
return(NLList);
}