Geography 485/585L: Internet Mapping

Module 2.3 - Web-based Mapping Clients: OpenLayers Javascript Framework

Part 1

Background

The Google Maps API provides one method for presenting an interactive mapping tool within a web browser, but there are restrictions for free use based upon Google’s license agreement, and the API is completely controlled by Google - changes are limited to those that Google enables. The OpenLayers Javascript framework which (as quoted from the project home page)

has been developed to further the use of geographic information of all kinds. OpenLayers is completely free, Open Source JavaScript, released under the 2-clause BSD License (also known as the FreeBSD).

Given its Open Source model, OpenLayers is managed as a community software project, with the development of specific capabilities driven by particular project or functionality needs that come out of the community.

This week’s class focuses on the basics of designing an OpenLayers interactive mapping client, including

At the end of this class the students will be able to:

Key Concepts

At the end of this class students will understand that

Lecture: Web Mapping Clients - OpenLayers

Presentation Slides

Notes related to recorded lecture and demonstrations

Lab Assignment: OpenLayers Mapping

Following the model used in Lab 3 for your first Google Map web page, you should first answer the following questions about what and how you want to map - relating to a different focus than you have used in your previous assignments. As you define the type of map you want to build, think about a specific problem or topic that you would like to address with your map.

In this exercise you will be generating the configuration for the base map (i.e. including one or more OpenLayer enabled background layers), adding controls, and defining an appropriate map center and zoom level for the map. You will add your own custom content to a free-standing web page that include an interactive mapper and the reasoning behind the design of the map.

Create a web page that contains your lab assignment writeup (including the embedded OpenLayers map required by question 5), link it to the home page (index.html) you previously created, and submit the direct link to your lab writeup web page through the Learn Assignment submission tool.

Respond to Question 1–4 with an understanding that you are generating a web page that is publicly accessible, and should be, clear, complete, well-formatted, and reasonably styled.

Peer Review: This assignment also has a peer-review component. In addition to submitting the link to your lab assignment write-up through the assignment submission page, create a new discussion thread within the Lab Assignment 8 Peer Review forum where you provide a link to your lab assignment write-up (which includes your base Google Map). Select two submissions (i.e. discussion threads created in the Lab Assignment 8 peer review forum) from other students and provide comments on their submission. Keep your comments constructive, and focus both on what is done well and areas where there could be improvement. In your comments consider layout, functionality, content and presentation. This portion of the assignment is worth two points, and is due on Friday - the day after the due-date for the lab assignment writeup.

Question 1
What area do you want to depict in your map? Why?
Question 2
What is the center point (latitude and longitude) of your area of interest?
Question 3
What base map(s) did you select for use in your map? Why?
Question 4
What is the scale of your map (local, regional, continental, global)? How will this translate into your selection of an appropriate default zoom level for your map?

Now that you have answered these questions about the map that you want to create, refer to the examples in the lecture notes, the OpenLayers Examples (http://openlayers.org/dev/examples/), and this week’s reading assignment to create a custom OpenLayers map.

Question 5
Embed the OpenLayers Map in your writeup (included with the answers to questions 1–4 above) that is based upon your responses to questions 1–4 above.