topic Re: Use Graphic and Layer Transform to Calculate New Points in ArcGIS JavaScript Maps SDK Questions

Use Graphic and Layer Transform to Calculate New Points

omega_cancer — Fri, 10 Dec 2021 20:33:22 GMT

I have 4 graphics on map with 3 map points and a polyline. As I am scaling / rotating polyline with editor I want 3 map points to calculate its new position relatively to scale or rotation of polyline.

 editToolbar.on('graphic-move-stop',function(evt){
 var graphicTransform = graphicDojoShape.getTransform();
 var layerTransform = evt.graphic.getLayer()._div.getTransform();

var wrapOffset = 0;
 var f = map.toScreen({x: roomGeometry.x, y: roomGeometry.y, spatialReference: spatialReference}, !0);
 f.x += wrapOffset;
 f = matrix.multiplyPoint([layerTransform, graphicTransform, matrix.invert(layerTransform)], f);
 f.x -= wrapOffset;
 f = map.toMap(f);
});

This code is not working.

Any clue?

Re: Use Graphic and Layer Transform to Calculate New Points

RobertScheitlin__GISP — Tue, 31 May 2016 01:35:37 GMT

Abdul,

I am not sure about your code but the way I do this is get the polygons centroid on the graphics-move-start and store this and then use graphics-move-end and get the new centroid and calculate the delta (difference between the two and that is what I would move the other points by.

Re: Use Graphic and Layer Transform to Calculate New Points

omega_cancer — Tue, 31 May 2016 09:36:07 GMT

Makes sense.

Delta between two centroids? But Room points might not be at centroid!

Can you please share the snippet?

Re: Use Graphic and Layer Transform to Calculate New Points

RobertScheitlin__GISP — Wed, 01 Jun 2016 03:19:10 GMT

Abdul,

Delta, meaning the centroids original coords were -89.256, 32.569 and the new moved centroid is -89.156, 32.469 the the simple math is to find the difference from the two which would be a delta of .100 and .100. SO if the polygons centroid moved .100 and .100 then the labels in your image would need to move the same amount so just move all three of them individually .100 and .100.

Re: Use Graphic and Layer Transform to Calculate New Points

omega_cancer — Wed, 01 Jun 2016 05:07:20 GMT

I am using something similar in my code but I thought it would be easy and every point specific (not just centroid - as I have rooms in my example) when we use graphic and layer transform properties.

I have seen use of graphic and layer transform properties for the said purpose somewhere.

Thanks for your time.