1. Intro to Virtual and Web Mapping
Today's Lecture Covers only the Basics
Preparing Maps for online display
Basics of the Online world
HTML, Javascript
KML
Internet Map Servers

2. Raster Graphics
Almost all maps displayed on a webpage will be converted to a Raster for display
Resolution
Bit-Depth (bitmap vs indexed image)
Color Palette
Alpha Channel
Re-sampling
Compression

3. Figure 16.1

4. Figure 16.2

5. Table 16.1

6. Table 16.2

7. Vector Format for Web Mapping
SVG (Scalable Vector Graphic)
5/Map_of_USA_with_state_names.svg
Flash / Flex
PDF
dlands/ms.pdf

8. Web Basics Web pages are written in a language called HTML
Hypertext markup language
It provides a means to create structured documents by denoting structural semantics for text such as headings, paragraphs, lists etc as well as for links, quotes, and other items. It allows images and objects to be embedded and can be used to create interactive forms. It is written in the form of HTML elements consisting of "tags" surrounded by angle brackets within the web page content.

9. Figure 16.3

10. Web Basics JavaScript CSS
Provides a way to modify or change the content in an HTML by accessing page elements based on user clicks or input
CSS
Cascading style sheets
Allows the web designer to make changes to the format or look of a webpage or website

11. Server Side Mapping
A mapserver is a computer that is running a special program that sends rater maps (map images) back to a user based on input parameters
USA_Topo_Maps/MapServer/export?bbox= %2C %2C %2C &bboxSR=4326&layers=&layerdefs=&size=&image SR=&format=png&transparent=false&dpi=&time=&l ayerTimeOptions=&f=html

12. Examples of Online Map Content
Climate Wizard
Coastal Resilience

13. Geographic Markup Languages
KML / GML / GeoRSS / GeoJSON
These are text based formats for sharing GIS data on the internet. They each have structured methods for storing both the geometry and attribute information.
Some, such as KML have methods for storing the cartographic or design elements of the spatial information

14. Design Implications for Thematic Mapping
Monitor is viewing medium
Refresh Rate
Number of pixels
Aspect ratio
~ 100 dpi
Color and Labeling

15. Figure 16.4

16. Animation Sharing data online opens up the ability for map animation
Fly-through Animation (Exploration)
Animation often depicts change over time
City population growth
Weather patters
Earthquakes
erwithfeaturelayer.html
Frame Based Animation
Raster based
Cast Based Animation
Vector Based

17. Figure 16.5

18. Figure 16.6

19. Figure 16.7