Gmap4 thread - Enhanced Google map viewer

[Jelf]

Since Angle of Repose mentioned a kind word for Gmap4 in a different thread, I decided to stop by, say hello and share a few tips.

By way of introduction, my name is Joseph and I am the developer of Gmap4.  This project is part of my way to "pay it forward". Translation: Gmap4 is free for non-commercial use.  It is popular with people that enjoy a wide range of outdoor activities.

In addition to displaying the standard Google basemaps, it can also display a vast amount of data hosted on GIS servers.  For example, the following link shows the Ordnance Survey map centered on a random spot in England’s Lake District National Park.

http://www.mappingsupport.com/p/gmap4.php?ll=54.458855,-3.167060&z=14&t=Ordinance_Survey&q=http://www.mappingsupport.com/p/demo_maps/demo_map_e.txt

This second example shows the Google aerial for a random spot in England with an overlay of contour lines with a 5 meter interval.

http://www.mappingsupport.com/p/gmap4.php?ll=53.256254,-1.717815&z=16&t=h,England_5m_contour_lines&q=http://www.mappingsupport.com/p/demo_maps/demo_map_e.txt

Gmap4 is a browser app, not a native app.  Gmap4 runs in most browsers on most devices from smartphones to desktops.  Note that the browser does have to be online in order for the app to start.  When Gmap4 is running in the browser on a smartphone or other mobile device it automatically uses a touch-friendly interface.

There are three ways to access different features:
1.  One button always shows the name of the current basemap.  Use this button to change the basemap, turn overlays on/off and restack overlays in a different order.
2.  The "Menu" button gives access to various features including geolocation, search, current declination and a "link to this map" feature. 
3.  A rightclick will show coordinates in various formats for the point you clicked.

The Menu ==> "Draw and Save" feature lets you add data to the map and then save your data as either a GPX file or a delimited text file.  You can also use the map-in-a-link feature to save your data right in the Gmap4 link itself and not have to bother with any data file.

Gmap4 can display these types of files:  GPX, TPO, KML, KMZ, Google MyMap, and a delimited file format.

The Gmap4 homepage has a FAQ, examples, quick start info (on the Help page) and more to quickly get you up to speed. 

One of the articles on the Help page shows you how to use Gmap4 on your smartphone offline.

Gmap4 default map: http://www.mappingsupport.com/p/gmap4.php

Gmap4 homepage:  http://www.mappingsupport.com/p/gmap4.html

Joseph, the Gmap4 guy
Redmond, Washington State, USA

[Angle of Repose]

Awesome! I just used G4maps this am for a trip I have coming up.

[captain paranoia]

The ability to display contours over a white base map is interesting, as that's a potentially useful way to teach contour interpretation; dump the student in at the deep end and give them no clues other than contours to navigate by.  Concentrates the mind, as it were...

BTW, what's the source of the contours?  I imagine the ultimate source is SRTM data, but processed into contours and (I assume) tiled.  The annotation is a bit intrusive, and it would be nice to have a 10m option.  And an 'every fifth contour' emboldened highlight (as per OS and other mapping providers).

[Jelf]

Thanks for the kind words.

Yes, the contour data was processed into tiles and is hosted on a GIS server.  Gmap4 can display those tiles but does not have any ability to change them.

Joseph