/// <summary>
/// 计算多边形和折线（包括线段）是否相交，（未考虑“回”字型）
/// </summary>
/// <param name="pd"></param>
/// <param name="line"></param>
/// <returns></returns>
public static bool CalcIfPolygonIntersectPolyline(PolygonD pd, PointDArray line)
{
if (!pd.Bounds.IntersectsWith(line.Bounds))
{
return(false);
}
PointD[] plg1 = pd.Points[0].Points;
PointD[] plg2 = line.Points;
PointD start1, end1, start2, end2;
for (int i = 0; i < plg1.Length; i++)
{
start1 = plg1[i];
end1 = (i == plg1.Length - 1) ? plg1[0] : plg1[i + 1];
for (int j = 0; j < plg2.Length - 1; j++)
{
start2 = plg2[j];
end2 = plg2[j + 1];
if (CrossLine(start1, end1, start2, end2) != 0)
{
return(true);
}
}
}
//补充判断多边形完全包含折线或线段的情况
if (PtInPolygon(line.Points[0].X, line.Points[0].Y, pd))
{
return(true);
}
return(false);
}
/// <summary>
/// 计算两个多边形是否相交。(未考虑“回”字型)
/// </summary>
/// <param name="pd1"></param>
/// <param name="pd2"></param>
/// <returns></returns>
public static bool CalcIfPolygonsIntersect(PolygonD pd1, PolygonD pd2)
{
if (!pd1.Bounds.IntersectsWith(pd2.Bounds))
{
return(false);
}
PointD[] plg1 = pd1.Points[0].Points;
PointD[] plg2 = pd2.Points[0].Points;
PointD start1, end1, start2, end2;
for (int i = 0; i < plg1.Length; i++)
{
start1 = plg1[i];
end1 = (i == plg1.Length - 1) ? plg1[0] : plg1[i + 1];
for (int j = 0; j < plg2.Length; j++)
{
start2 = plg2[j];
end2 = (j == plg2.Length - 1) ? plg2[0] : plg2[j + 1];
if (CrossLine(start1, end1, start2, end2) != 0)
{
return(true);
}
}
}
return(CalcPolygonContainsPolygon(pd1, pd2) || CalcPolygonContainsPolygon(pd2, pd1));
}
/// <summary>
/// 判断多边形是否和一个矩形相交
/// </summary>
/// <param name="pd"></param>
/// <param name="rd"></param>
/// <returns></returns>
public static bool CalcIfPolygonIntersectRectangle(PolygonD pd, RectangleD rd)
{
if (!pd.Bounds.IntersectsWith(rd))
{
return(false);
}
if (CalcPolygonIntersect(pd.Points[0].Points, rd).Length == 0)
{
return(false);
}
return(true);
}
/// <summary>
/// 计算多边形(不含“回”字型)是否包含一个矩形
/// </summary>
/// <param name="pd"></param>
/// <param name="rd"></param>
/// <returns></returns>
public static bool CalcPolygonContainsRectangle(PolygonD pd, RectangleD rd)
{
if (!pd.Bounds.IntersectsWith(rd))
{
return(false);
}
PointD[] rc = CalcPolygonIntersect(pd.Points[0].Points, rd);
if (rc.Length > 2)
{
byte result = 0x00;
for (int i = 0; i < rc.Length; i++)
{
if ((rc[i].X != rd.Left && rc[i].X != rd.Right) || (rc[i].Y != rd.Top && rc[i].Y != rd.Bottom))
{
return(false);
}
if (rc[i].X == rd.Left && rc[i].Y == rd.Top)
{
result |= 0x01;
}
if (rc[i].X == rd.Right && rc[i].Y == rd.Top)
{
result |= 0x02;
}
if (rc[i].X == rd.Right && rc[i].Y == rd.Bottom)
{
result |= 0x04;
}
if (rc[i].X == rd.Left && rc[i].Y == rd.Bottom)
{
result |= 0x08;
}
}
if (result == 0x0f)
{
return(true);
}
else
{
return(false);
}
}
else
{
return(false);
}
}
/// <summary>
/// 计算点是否在多边形内(包括“回”字型)
/// </summary>
/// <param name="x"></param>
/// <param name="y"></param>
/// <param name="pd"></param>
/// <returns></returns>
public static bool PtInPolygon(double x, double y, PolygonD pd)
{
if (!pd.Bounds.Contains(x, y))
{
return(false);
}
int count = 0;
for (int i = 0; i < pd.Points.Count; i++)
{
if (ptInRgn(x, y, pd.Points[i].Points))
{
count++;
}
}
return(count % 2 == 1);
}
public static bool CalcPolygonContainsRectangle2(PolygonD pd, RectangleD rd)
{
bool result = CalcRegionContainsRectangle2(pd.Points[0], rd);
if (pd.Points.Count > 1 && result)
{
for (int i = 1; i < pd.Points.Count; i++)
{
if (CalcRegionContainsRectangle2(pd.Points[i], rd) || calcIfPolygonIntersect(pd.Points[i].Points, rd))//CalcPolygonIntersect(pd.Points[i].Points,rd).Length>0)
{
return(false);
}
}
return(true);
}
else
{
return(result);
}
}
/// <summary>
/// 计算多边形(含“回”字型)是否包含另一个多边形
/// </summary>
/// <param name="pdOutter"></param>
/// <param name="pdInner"></param>
/// <returns></returns>
public static bool CalcPolygonContainsPolygon(PolygonD pdOutter, PolygonD pdInner)
{
if (!pdOutter.Bounds.IntersectsWith(pdInner.Bounds))
{
return(false);
}
if (!CalcRegionContainsRegion(pdOutter.Points[0], pdInner.Points[0]))
{
return(false);
}
if (pdOutter.Points.Count > 1)
{
for (int i = 1; i < pdOutter.Points.Count; i++)
{
if (CalcRegionContainsRegion(pdInner.Points[0], pdOutter.Points[i]))
{
return(false);
}
}
}
return(true);
}
public static bool CalcIfPolygonIntersect(PolygonD pd1, PolygonD pd2)
{
return(pd1.Bounds.IntersectsWith(pd2.Bounds));
}