Dynamic Maps
Dynamic Features
The ability to dynamically update maps based on changing conditions is a critical part of most mapping applications. We provide a number of APIs and structures to help you do this easily and efficiently.
Our overlay system allows you to group various layers allowing you to efficiently refresh each overlay independently. While layers are platform independent and part of ThinkGeo’s Core, overlays are platform dependent and take advantage of each platform’s drawing system. Additionally, it is at the overlay level that we implement editing, popups and markers.
A common scenario this is used is in vehicle tracking. Typically, you would have a set of base layers that represent the roads, parks, and buildings along with moving vehicles. Using overlays, you can place all of your base layers in one overlay, then isolate the vehicle layer on an overlay. With that in place, you can independently call the refresh method on just the vehicle overlay, redrawing just the vehicles and saving system resources from drawing the base layers. Using just this technique, you can easily refresh 20,000 polygons every second, changing their color, while still retaining responsive user input.
Editing
Easily create or edit features using ThinkGeo’s TrackOverlay and EditOverlay tools. These built-in tools only take a few lines of code to implement and allow you rotate, move, shrink and expand shapes directly on the map. It's also capable of adding, removing and modifying a feature’s nodes.
Any changes made to the features are cached in memory until committed to the underlaying feature source. You can also easily modify the visual style of the features being edited, allowing for distinct edit mode visualizations.
Sample Code
* Feature available, but no specific sample.