topic Re: Panning around the world - geometry contains() test fails in ArcGIS JavaScript Maps SDK Questions

Panning around the world - geometry contains() test fails

JonathanTiu — Wed, 06 Sep 2023 16:38:01 GMT

Using the sketchviewmodel i have drawn a graphic which acts like a polygon filter on the map.

Anyways, i have added logic such that clicking inside the polygon pops up a custom toolbar etc.

To do all this, my code is something like this:

mapView.hitTest(clickCoordinates).then((response: any) => {

if (response.results.length === 0) {
const polygonFilter = getPolygonFilterGraphic(layer);

// check if the click coordinates is inside the polygon filter
const point = new esri.Point({

x: event.mapPoint.x, y: event.mapPoint.y, spatialReference: esri.SpatialReference.WebMercator

);
if (polygonFilter && polygonFilter.geometry.contains(point)) {

// pop up the toolbar
}

This works fine except in the case where i pan around the world. so in my screenshot above if i pan around the world and arrive at this polygon filter over japan again, if i click inside it, the mapPoint is never inside the polygonFilter.geometry (ie. the contains() predicate always fails.)

I suspect it has to do with the mapPoint's x coordinate being outside the current extent xmin and xmax. do i need to be normalizing the mapPoint or the polygonFilter.geometry or both? and if so, how do i normalize it? Any help would be appreciated thanks!

Re: Panning around the world - geometry contains() test fails

JoelBennett — Wed, 06 Sep 2023 17:28:59 GMT

If your polygon is always a rectangle, then the issue is straightforward:

var extents = polygonFilter.geometry.extent.clone().normalize(); var nPoint = point.clone().normalize(); for (var x = 0; x < extents.length; x++) { if (extents[x].intersects(nPoint)) { //pop up the toolbar break; } }

Re: Panning around the world - geometry contains() test fails

JonathanTiu — Wed, 06 Sep 2023 17:40:40 GMT

It won't always be a rectangle. we allow freeform filter like this.

I see, you're normalizing the extent of the polygon filter's geometry. does your approach not work for arbitrary shapes? i guess the extent is a rectangle...

Re: Panning around the world - geometry contains() test fails

JoelBennett — Wed, 06 Sep 2023 17:58:23 GMT

If your polygon won't cross the international dateline, then you can normalize it on the client-side by rebuilding it from normalized points. If it could could cross it, then perhaps the recommended solution for normalizing the polygon would be to use normalizeUtils.normalizeCentralMeridian. Whatever method you choose, I recommend you normalize the polygon before adding it to your GraphicsLayer.

Anyhow, assuming the polygon is normalized, then it would just be a matter of:

if (polygonFilter && polygonFilter.geometry.contains(point.clone().normalize())) { // pop up the toolbar }