topic Re: Symbol size not affected by map zoom in ArcGIS Runtime SDK for iOS Questions

Symbol size not affected by map zoom

SimonFox — Mon, 11 May 2015 16:24:53 GMT

Hi folks,

I have a server sending me symbols onto my map. They're quite small when zoomed out. When I zoom in on my AGSMapView, I can see the symbols increasing in size as I'd want them to.

However as soon as I left go of the zoom gesture, the symbols snap back to the tiny resolution. So the result is that regardless of the map scale, the symbols remain tiny.

We tried making their images very large on the server as a test, but it's the same. Seems to be a client-side issue.

Any ideas on what I could do?

Thanks guys, much appreciated.

Simon.

Re: Symbol size not affected by map zoom

RickeyFight — Mon, 11 May 2015 16:34:43 GMT

Simon,

Have you checked the source mxd reference scale?

To get to this menu Right click on Layers in the Table of Contents --> General Tab

Re: Symbol size not affected by map zoom

SimonFox — Mon, 11 May 2015 16:38:47 GMT

Thanks Rickey, I'll pass this on to our server manager and see if it helps. Back soon.

Re: Symbol size not affected by map zoom

SimonFox — Mon, 11 May 2015 16:45:41 GMT

Ok, yes we had tried that, but made no difference unfortunately.

Re: Symbol size not affected by map zoom

RickeyFight — Mon, 11 May 2015 17:01:35 GMT

Can you share the link or the service?

Re: Symbol size not affected by map zoom

ToddBlanchette — Mon, 11 May 2015 17:34:29 GMT

As Rickey stated, the data frame's reference scale would set up symbology that got bigger or smaller as you zoomed past or away from that set scale level. If you have no reference scale (the default) then the symbology will remain whatever size you published it at, at all scale levels. If the symbology itself is not changing after you've changed the size of the symbol and republished the service, then there is an issue with whatever web app you're using to visualize your layer.

Re: Symbol size not affected by map zoom

SimonFox — Mon, 11 May 2015 17:38:21 GMT

I'm using the iOS components to view the layer, so I'm pretty sure it's a server config issue.

I'll try and get permission for Rickey to take a look. Will have to go offline with it

Thanks guys.

Re: Symbol size not affected by map zoom

SimonFox — Mon, 11 May 2015 17:42:47 GMT

Hi Rickey, could I send the server details by email? It's proprietary data, so can't post publicly.

I'm at simonfoxguitar@gmail.com

Thanks so much, really appreciate your help.

Re: Symbol size not affected by map zoom

SimonFox — Mon, 11 May 2015 19:03:25 GMT

Thanks for Rickey for taking a look. The native app view behaves quite different to the browser view.

I tested this with one of the ESRI sample apps, and the same zoom problem seems to occur.

Does anyone from the iOS dev team have a comment?

Re: Symbol size not affected by map zoom

RickeyFight — Mon, 11 May 2015 19:10:59 GMT

Simon,

I am sorry to hear it is not a simple fix

If you want esri iOS dev team help I might unmark my answer as correct.

Re: Symbol size not affected by map zoom

SimonFox — Mon, 11 May 2015 20:17:24 GMT

I tracked all the actual AGSPictureMarkerSymbols in my layer via the AGSRenderer object.

The image size is very small (6x6) (ish)

Also used a proxy server to see the image data. The images are small on arrival.

I can scale the symbols up by setting the size attribute of the symbols, but of course the images are too fuzzy.

I noticed that the feature layer rendering mode was "static" not dynamic. Not sure if that matters.

Is there something I should be doing when I call initWithURL for my feature layer perhaps? Some attribute that needs to be set?

Why would the server scale down the vector images so low?

Re: Symbol size not affected by map zoom

DiveshGoyal — Tue, 19 May 2015 22:07:01 GMT

Simon,

What you're seeing is expected. The AGSPictureMarkerSymbol uses an image to render the symbol. The size of the symbol depends on the size of the image. So if the image is 6 pixels x 6 pixels, that's how big it'll be displayed on screen. Now, you can override the size property of the symbol to make it larger, but that would force the image to be scaled possibly making them fuzzy.

When you pinch to zoom in, the feature layer waits till the gesture is over to re-render its content, and in the meanwhile, it just re-scales the content on screen. It does this because you could potentially have a lot of features in your layer, and re-rendering it while the gesture is in progress would be very CPU intensive and might deteriorate the responsiveness of the map. Thus, the symbol might temporarily appear larger as it is re-scaled while the gesture is in progress. And yes, this behavior is specifically tied to the "static" mode.

The "dynamic" mode is more suitable to graphics layer (not feature layers) which typically have only a few graphics. In this mode, the content is drawn using the GPU (not CPU as with static mode). The GPU fares much better at re-rendering content on-the-fly while the gesture is in progress. So you would not see picture marker symbols temporarily appear fuzzy, they would always be their true size.

But in both the cases, the picture marker symbol is drawn based on the size of the image (unless overriden in code)

Re: Symbol size not affected by map zoom

LasseReedtz — Tue, 01 Dec 2015 12:28:02 GMT

Did you ever find a solution ?

I'm trying to find a solution to the same problem, but for the windows desktop runtime sdk

- Lasse