topic SPATIAL_REL_INTERSECTS in Web AppBuilder Custom Widgets Questions

SPATIAL_REL_INTERSECTS

LefterisKoumis — Sun, 12 Dec 2021 09:23:59 GMT

I want to replicate the behavior of Arcmap analysis tools/overlay/intersect tool by using SPATIAL_REL_INTERSECTS.

In that tool, when you specified two polygon classes, it doesn't matter the order, the area of intersection is the same.

I want the users to be able to use any two polygon classes to run the intersect tool to get the intersected area.

I am using the script below. If I switch the first layer with the second the results are different. Why? The intersected area should be the same regardless which layer is specified as first or second. Thanks.

var firstgraphics = [];
            var features = [];
            array.forEach(firstlayer.graphics, function (feature) {
              firstgraphics.push(feature.geometry)
            })

            var secondgraphics = [];
            array.forEach(secondlayer.graphics, function (feature1) {
              secondgraphics.push(feature1.geometry)
            })
           

            var queryTask = new esri.tasks.QueryTask(firstlayer.url);
            queryTask.on("error", this.queryTaskErrorHandler);
            for (j = 0; j < secondgraphics.length; j++) {
              query = new esri.tasks.Query();
              query.geometry = secondgraphics[j];
              query.returnGeometry = true;
              query.where = "1=1";
              query.maxAllowableOffset=0;
              query.distance=0;
              query.outFields = ["*"];
              query.outSpatialReference = this.map.spatialReference;
              query.spatialRelationship = esri.tasks.Query.SPATIAL_REL_INTERSECTS;
              queryTask.execute(query, function (results) {
                  for (i = 0; i < results.features.length; i++) {
                    console.log(results.features[i].attributes);
                   // thefeatureSet =  results.results;
                    var graphic = new esri.Graphic(results.features[i].geometry, inter_symbol);
                    bufferGraphicsLayer.add(graphic);
                  }
                })
              }
            

              this.map.addLayer(bufferGraphicsLayer);
           
            },‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

Re: SPATIAL_REL_INTERSECTS

RobertScheitlin__GISP — Wed, 01 Aug 2018 12:53:01 GMT

Lefteris,

It makes perfect sense that they are different depending on which layer is specified as the source layer. You are doing a QueryTask which is just giving you the features that intersect (meaning Part of a feature from feature class 1 is contained in a feature from feature class 2). You are not doing a GeometryService Intersect operation where the geometry returned is the intersecting portions of the two geometries. The QueryTask will just return the full features that intersects the other feature.

Re: SPATIAL_REL_INTERSECTS

LefterisKoumis — Wed, 01 Aug 2018 16:05:21 GMT

Got it. Your response: "The QueryTask will just return the full features that intersects the other feature." should be included in ESRI docs.

One more question. Do you know what the Arcmap analysis tools/overlay/intersect tool is running on? I am trying to create a tool to use in wab where you don't specify a source layer. Thanks.

Re: SPATIAL_REL_INTERSECTS

RobertScheitlin__GISP — Wed, 01 Aug 2018 16:10:26 GMT

Lefteris,

What ArcMap does is based on ArcObjects on the desktop machine and NOT applicable to a Server environment. The only option you have is to use GeometryService.intersect or GeometryEngine.intersect.

Re: SPATIAL_REL_INTERSECTS

LefterisKoumis — Wed, 01 Aug 2018 16:41:18 GMT

ok. Thank you.