public SelectResult SelectPoint(GISVertex vertex, List <GISFeature> features,
GISView view, GISExtent MinSelectExtent)
{
Double distance = Double.MaxValue;
int id = -1;
for (int i = 0; i < features.Count; i++) //找最近的feature判断是否有效
{
if (MinSelectExtent.IntersectOrNot(features[i].spatialpart.extent) == false)
{
continue;
}
GISPoint point = (GISPoint)(features[i].spatialpart);
double dist = point.Distance(vertex);
if (dist < distance)//每次找到最小的距离并记录id号
{
distance = dist;
id = i;
}
}
Console.WriteLine("id:" + id.ToString()); //测试id是否存在
Console.WriteLine(features[id].spatialpart.centroid.x.ToString() + "|" + features[id].spatialpart.centroid.y.ToString());
Console.WriteLine("鼠标点到元素点在地图上相距" + distance.ToString()); //此处的distance是features中最近的元素点到鼠标点映射到地图上点的距离
//精选
if (id == -1) //经过遍历 没有与minsextent相交的点则跳出
{
SelectedFeature = null;
return(SelectResult.TooFar);
}
else
{
double screendistance = view.ToScreenDistance(vertex, features[id].spatialpart.centroid);
//Console.WriteLine(screendistance);
if (screendistance < GISConst.MinScreenDistance)
{
SelectedFeature = features[id];
return(SelectResult.OK);
}
else
{
SelectedFeature = null;
return(SelectResult.TooFar);//即使在粗选相交 精选距离也超过了限制 则返回
}
}
}
public SelectResult SelectLine(GISVertex vertex, List <GISFeature> features,
GISView view, GISExtent MinSelectExtent)
{
Double distance = Double.MaxValue;
int id = -1;
for (int i = 0; i < features.Count; i++) //找最近的feature判断是否有效
{
if (MinSelectExtent.IntersectOrNot(features[i].spatialpart.extent) == false)
{
continue;
}
GISLine line = (GISLine)(features[i].spatialpart);
double dist = line.Distance(vertex);
//Console.WriteLine("dist:" + dist);
if (dist < distance)//每次找到最小的距离并记录id号
{
distance = dist;
id = i;
}
}
Console.WriteLine("id:" + id.ToString());//测试id是否存在
//Console.WriteLine(distance);
//精选
if (id == -1)//经过遍历 没有与minsextent相交的点则跳出
{
SelectedFeature = null;
return(SelectResult.TooFar);
}
else
{
double screendistance = view.ToScreenDistance(distance);
if (screendistance < GISConst.MinScreenDistance)
{
SelectedFeature = features[id];
return(SelectResult.OK);
}
else
{
SelectedFeature = null;
return(SelectResult.TooFar);//即使在粗选相交 精选距离也超过了限制 则返回
}
}
}
