Three ways to display ArcGIS MapServer and ImageServer data
Method 1: Identify GIS data as part of a Gmap4 link
This simple syntax
can be used to display any ArcGIS MapServer layers or basemaps. Any necessary re-projection is handled by ArcGIS Server on-the-fly. This method is best suited for maps with just a few layers of GIS data.
For ImageServer data the syntax is even easier:
Here is what the parameters mean.
rest= Link to MapServer or ImageServer data
name= You make up a name but it should be similar to the name used on the GIS server. Use an underline character instead of a space.
layers= Layer number or numbers for this data on the GIS server.
transparent= To make the layer an overlay set this to true. To make this data a basemap set this to false.
Here is a Gmap4 map showing stream gages. If you click a gage then you will see a display with all the attribute data the GIS server has for the thing that you clicked. That attribute data includes a link that will display a very nice graph plus lots of additional information. Note that the &markers parameter is used to put a title on the map and %20 in the title is computer-speak for a space.
A Gmap4 link can identify multiple GIS layers for the map. This next map link identifies two GIS layers. Click the basemap button and then look under the "Overlay" heading. Mobile users need to scroll down. Click the "Weather_watch_warning" layer to turn it on. The overlay layer with the highest number is on 'top' and can be clicked.
Below is an example of a Gmap4 map that displays ImageServer data. These aerial photos cover Phoenix and the surrounding area. The default for ImageServer data is transparent=false which means that this data will be a basemap instead of an overlay.
Method 2: Identify GIS data in a text file
This is a good method to use when you want to have more than just a few GIS layers on a map. Here are the steps:
1. Make a text file that identifies the GIS layers for the map.
2. Put the text file online. Google Sites provides free hosting.
3. Make a Gmap4 link that points to the text file.
Here is a text file that is hosted on the MappingSupport server. This file identifies 20+ GIS layers related to rain and flooding. You can download this file and look at its contents. Lines that begin with // are comment lines. Note that the file includes a "title=" line which displays a title on the map.
The following Gmap4 link points to that text file. To turn GIS overlay layers on/off and restack them, click the basemap button (next to the "Menu" button) and then look under the "Overlay" heading. An overlay with a number in front is 'on'. The highest numbered overlay is on 'top' and can be clicked to display all the attribute data the GIS server has for the thing that you clicked. Sometimes that attribute data will include a link that leads to more information.
Note that the above map has a link in the upper left corner titled "Map tips". That link displays a web page with links to the map legend and other useful information. Instead of a web page the "Map tips" information could be put into a PDF file. You can host your text file and PDF file on Google Sites for free. For step-by-step instructions for using Google Sites, please go to the Gmap4 help page and download the pdf file 'Working With Files' and search that file on 'google sites'.
If you would like to see more examples of Gmap4 maps that use text files to display many layers of GIS data, then please visit the MappingSupport project page and scroll down to the section titled "Gmap4 Special Maps".
Method 3: Open Gmap4 and then surf GIS data almost as easy as you surf the internet
...Coming in 2018...
Are you a GIS beginner and would like more information?
You can find some background on GIS servers plus another explanation of using Gmap4 to view GIS data at: