Modifying or pooling ArcGisPoint?

genarus

Here I am again.

I want to move hundreds of objects on the global map using Web-Mercator positions. Apparently you have to use the ArcGisPoint API, but for some reason ArcGisPoint is a class & immutable. So if I want to move lots of objects every frame, I have to create lots of new instances of it. Which leads to an incredible amount of garbage and poor performance.

Hence my question, is there any way to reuse, modify or pool ArcGisPoint? I found another ArcGisPointBuilder, so you can at least modify a point. However, you still have to create a new class for each modification, so it is not more performant. So how would you handle this in scenarios where many objects have to move?

Could any official team member or dev please comment on this?

AShahbaz

You might get some performance gain by using ArcGISMutablePointCollection, but you still wont be able to modify the individual points in the collection. I don't think you can avoid using ArcgisPoint or ArcGISLocationComponent unless you implement the conversion to the engine coordinates yourself (I assume you are using `GeographicToEngine` for the projection).

Since you are using a projected coordinate system, you might be able to keep track of the changes over time and apply the offset without reprojecting to engine coordinates. So in if an object is at (0,0,0) in web mercator at frame 0 and at (1,0,0) in the next frame, you could move the object by one meter toward east in the engine. But my guess is that the objects will start to drift from the actual location and you would have to do a projection every few frames.

Similarly, if the objects are moving in a somewhat predicable manner (e.g. airplanes), you could improve the performance by doing the conversion to engine coordinates less frequently (say once per second). For the frames in-between you would move the object by interpolating between the two calculated locations.