topic Re: Reordering ArcGISImageServiceLayer in ArcGIS JavaScript Maps SDK Questions

Reordering ArcGISImageServiceLayer

BryanSng1 — Mon, 23 May 2016 09:15:04 GMT

Hi guys,

Is there a way to reorder ArcGISImageServiceLayer (ArcGISImageServiceLayer | API Reference | ArcGIS API for JavaScript ) using the Map reorderLayer method (Map | API Reference | ArcGIS API for JavaScript ) ?

I notice that it will be created as

<div> under <div> with class="esriMapLayers"

instead of

<g> under <svg>

where all the feature layers are loaded into

I think this maybe the reason why reorderLayer does not work for ArcGISImageServiceLayer.

I'm ok with any method as long as I can do reordering of ArcGISImageServiceLayer with FeatureLayer.

Alternatively, is there any way I can display a raster image that support reordering?

Thanks!

Re: Reordering ArcGISImageServiceLayer

FC_Basson — Mon, 23 May 2016 11:01:15 GMT

Do you want to manipulate the order of the image data sets in the Image Service? Then you will need to apply a mosaic rule on the Image Service (see ArcGISImageServiceLayer | API Reference | ArcGIS API for JavaScript and MosaicRule | API Reference | ArcGIS API for JavaScript ). The map reorderLayer function only applies to the layer order of the map and not the drawing order within a layer.

Re: Reordering ArcGISImageServiceLayer

BryanSng1 — Mon, 23 May 2016 13:15:53 GMT

Hmm not really, more like imagine I got the following layers for a train station:

1) Feature layer A to showcase [Toilet]

2) Feature layer B to showcase [Trash Bin]

3) Image layer C to showcase [Station Layout]

User can use a control to manipulate which layer should be on top of which one such that if I were to state that Image layer C is the last of them, then I will not be able to see Feature layer A and B since Image layer C will cover them.

Re: Reordering ArcGISImageServiceLayer

FC_Basson — Fri, 10 Dec 2021 21:23:43 GMT

The layer order is index based with 0 being the bottom layer, so if you want to move a layer to the top then you can do it like this:

var fromtop = 0;  // layer order of visibility from the top
map.reorderLayer(layer, map.layerIds.length - 1 - fromtop);

Re: Reordering ArcGISImageServiceLayer

BryanSng1 — Tue, 24 May 2016 01:09:07 GMT

Hmm, yeah but unfortunately, that works only for the feature layers, image layer does not react to any reorderLayer call.

Most probably due to the way image layer render itself to the dom (separate div rather of g within svg)

Re: Reordering ArcGISImageServiceLayer

BryanSng1 — Fri, 10 Dec 2021 21:23:46 GMT

I realise that ArcGISImageServiceVectorLayer | API Reference | ArcGIS API for JavaScript is able to render raster layer as g within svg but unlike my feature layer, it is missing the path that are supposed to be in it.

Here's an example of the path:

Is there something special I should do to configure the image server or is it my js code?

My invocation is as follows:

var layer = new ArcGISImageServiceVectorLayer(url);
map.addLayer(layer);

Re: Reordering ArcGISImageServiceLayer

FC_Basson — Tue, 24 May 2016 07:29:53 GMT

First issue with this question, you asked about an ArcGISImageServiceLayer, which is inherits from a different class (DynamicMapServiceLayer) than a ArcGISImageServiceVectorLayer (GraphicsLayer). I think the graphics layers always render on top of the Dynamic layers, but if the layers you want to reorder are all from the Graphics layer type, you should still be able to reorder them. See this fiddle - click the switch button and layer order changes.

Re: Reordering ArcGISImageServiceLayer

BryanSng1 — Wed, 25 May 2016 11:34:12 GMT

The difference between the 2 layers type is good information. This assure me that using ArcGISImageServiceVectorLayer is the right way to go in order to play well in reordering with feature layers.

Now I would need to find out how to display the image layer as it always does not render. The online api states that:

The ArcGISImageServiceVectorLayer displays pixel values as vectors. To do this, the image service layer must be a two-band raster in which one band holds magnitude values and one band holds direction values. The ArcGISImageServiceVectorLayer also supports time-enabled data.

Currently my image layer has 3 bands (auto created when I import the image into ArcMap), do you think this is the problem?

Re: Reordering ArcGISImageServiceLayer

FC_Basson — Wed, 25 May 2016 11:38:00 GMT

I would think so. Try loading a single band of the image layer.

Re: Reordering ArcGISImageServiceLayer

BryanSng1 — Mon, 30 May 2016 09:46:20 GMT

Hmm so far I hasn't had much luck with 1 band raster (by converting 3 band raster into 1 band raster). I also notice that the online article mention magnitude and direction values, I thought band should be holding color values?

Re: Reordering ArcGISImageServiceLayer

BryanSng1 — Thu, 02 Jun 2016 10:13:03 GMT

Hmm I'm quite juiced out of ideas, if I start from scratch again, does anyone know any ideas on how to reorder raster and feature layers?

Re: Reordering ArcGISImageServiceLayer

FC_Basson — Thu, 02 Jun 2016 10:17:38 GMT

Can you provide us with some sample code to see why it is not working?

Re: Reordering ArcGISImageServiceLayer

BryanSng1 — Fri, 10 Dec 2021 21:23:48 GMT

The code is pretty simple:

var map = new Map("mapDiv");
var basemap = new ArcGISTiledMapServiceLayer("http://10.229.85.29/arcgis/rest/services/demoBasemap/MapServer");
var featureLayer = new FeatureLayer("http://10.229.85.29/arcgis/rest/services/demoFeature/MapServer/0");
var rasterLayer = new ArcGISImageVectorServiceLayer("http://10.229.85.29/arcgis/rest/services/demoRaster/ImageServer"); // 1 band raster layer
map.addLayer(basemap); // showing
map.addLayer(featureLayer); // showing
map.addLayer(rasterLayer); // not showing

I think the key concern is in http://10.229.85.29/arcgis/rest/services/demoRaster/ImageServer

Our image is like the layout of a train station that we scan into the computer and import it as a raster layer.

Don't think it has the directional or magnitude values as per the provided online sample

Re: Reordering ArcGISImageServiceLayer

FC_Basson — Thu, 02 Jun 2016 11:44:08 GMT

The API reference (ArcGISImageServiceVectorLayer | API Reference | ArcGIS API for JavaScript ) states that the ArcGISImageVectorServiceLayer must have 2 bands: "To do this, the image service layer must be a two-band raster in which one band holds magnitude values and one band holds direction values."

Will normal ArcGISImageServiceLayer not be sufficient?

Re: Reordering ArcGISImageServiceLayer

BryanSng1 — Fri, 03 Jun 2016 01:44:02 GMT

The current situation is like:

ArcGISImageServiceLayer can only display the layer but cannot reorder the layer between feature layer

ArcGISImageServiceVectorLayer cannot display the layer but can reorder the layer between feature layer

Hmm, imagine I got the train station layout raster and a feature layer that show where the exit point are

Our requirement is to be able to reorder the map such that if I reorder train station layout on top of exit point

The train station layout will cover the exit point

If I reorder exit point on top of train station layout

The exit point will overlay on top of train station layout

Currently, the choke point is the "cover the exit point" part because station layout will always render behind the exit point