/// <summary>
///
/// </summary>
/// <param name="poly1"></param>
/// <param name="poly2"></param>
/// <param name="poly"></param>
/// <param name="curedge"></param>
private static void SetInitData(Polygon2D poly1, Polygon2D poly2, ref Polygon2D poly, ref Double2Bool curPoint, ref int curedge)
{
if (poly1 == null || poly2 == null || poly1.GetEdgeNum() < 3 || poly2.GetEdgeNum() < 3)
{
return;
}
// 先找poly1 最小的。
poly = poly1;
curedge = 0;
Double2Bool min = poly1.GetPointPlus(0);
for (int i = 1; i < poly1.GetEdgeNum(); i++)
{
Double2Bool point = poly1.GetPointPlus(i);
if (point.y < min.y || (point.y == min.y && point.x < min.x))
{
min = point;
curedge = i;
}
}
//
for (int i = 0; i < poly2.GetEdgeNum(); i++)
{
Double2Bool point = poly2.GetPointPlus(i);
if (point.y < min.y || (point.y == min.y && point.x < min.x))
{
min = point;
curedge = i;
poly = poly2;
}
}
curPoint = min;
}
/// <summary>
/// 求多边形的并。
/// </summary>
/// <param name="polygon1"></param>
/// <param name="polygon2"></param>
/// <returns></returns>
private static Double2Bool[] CombinePolygon(Double2Bool[] polygon1, Double2Bool[] polygon2, ref bool isCombine)
{
isCombine = true;
if (polygon1 == null || polygon1.Length < 3)
{
return(null);
}
if (polygon2 == null || polygon2.Length < 3)
{
return(polygon1);
}
//
Polygon2D poly1 = new Polygon2D(polygon1);
Polygon2D poly2 = new Polygon2D(polygon2);
// 获取poly1每条线段上的交点。
List <Double3>[] Poly1IntersectArray = new List <Double3> [poly1.GetEdgeNum()];
List <Double3>[] Poly2IntersectArray = new List <Double3> [poly2.GetEdgeNum()];
GetAllEdgeInterSectPoint(poly1, poly2, ref Poly1IntersectArray, ref Poly2IntersectArray);
bool CheckIntersect = false;
foreach (List <Double3> list in Poly1IntersectArray)
{
if (list != null && list.Count > 0)
{
CheckIntersect = true;
break;
}
}
if (CheckIntersect == false)
{
isCombine = false;
ClearPolyIntersectArray(ref Poly1IntersectArray, ref Poly2IntersectArray);
return(polygon1);
}
//
List <Double2Bool> listPoint = new List <Double2Bool>();
Polygon2D poly = null;
int curedge = 0;
Double2Bool curPoint = new Double2Bool(0, 0, true);
bool SearchDir = true;
List <Double3>[] curPolyIntersectArray = null;
SetInitData(poly1, poly2, ref poly, ref curPoint, ref curedge);
if (poly == poly1)
{
curPolyIntersectArray = Poly1IntersectArray;
}
else if (poly == poly2)
{
curPolyIntersectArray = Poly2IntersectArray;
}
while (poly != null && curedge >= 0 && curedge < poly.GetEdgeNum())
{
Point2D ls2d = poly.GetSimpleEdge(curedge);
Double2 normalDir = poly.GetNormal(curedge);
if (AddPoint(ref listPoint, curPoint) == false)
{
break;
}
Double3 nextPoint = Double3.zero;
bool ret = GetNearPointInEdge(ls2d, SearchDir, curPoint, curPolyIntersectArray[curedge], ref nextPoint);
if (ret == false)
{
if (SearchDir == true)
{
curedge++;
if (curedge >= poly.GetEdgeNum())
{
curedge = 0;
}
curPoint = poly.GetPointPlus(curedge);
}
else
{
curedge--;
if (curedge < 0)
{
curedge = poly.GetEdgeNum() - 1;
}
curPoint = poly.GetPointPlus(curedge + 1);
}
}
else // 则需要交换了。换到另一个多边形。
{
// 肯定是边上的点了, 强制设置为true，可通过
curPoint = new Double2Bool(nextPoint.x, nextPoint.y, true);
curedge = (int)nextPoint.z;
ExChangePoly(ref poly, poly1, poly2, ref curPolyIntersectArray, Poly1IntersectArray, Poly2IntersectArray);
Point2D ls = poly.GetSimpleEdge(curedge);
if (Double2.Dot(ls.endPoint - ls.startPoint, normalDir) > 0)
{
SearchDir = true;
}
else
{
SearchDir = false;
}
}
}
ClearPolyIntersectArray(ref Poly1IntersectArray, ref Poly2IntersectArray);
return(listPoint.ToArray());
}
