Spire Chart Overview
Sample Application: Usenet Views
How to Add a Spire Chart to Your Application
A spire chart is a data visualization tool invented by Fernanda Viegas, who worked as a summer intern for the Microsoft Research Community Technologies team. Here is a sample spire chart:
A spire chart has a column for each week in a specified year. The start date of each week is displayed along the x axis. The chart has an upper half and a lower half, with a dividing line in the middle and a label for each half on the y axis.
The chart has a collection of bubbles. Each bubble has a start date and an upper/lower flag that determine where the bubble is drawn, and a size metric that determines the size of the bubble. The bubbles in the upper half of each column are stacked vertically in order of size, with the largest bubble at the bottom and the smallest at the top. The bubbles in the lower half are stacked with the largest bubble at the top and the smallest at the bottom.
Spires can be transparent to allow covered bubbles to show through. If there are more bubbles in a stack than will fit within the chart, the "overflow" bubbles are clipped.
There are two .NET spire chart components. SpireChartGenerator is a drawing engine without its own user interface. It takes a set of bubble data, generates a spire chart from the data, and draws it onto a bitmap or Graphics object provided by the caller. It can be used in a variety of environments, including Web applications that generate images on the server for downloading to client browsers.
The SpireChartControl wraps the SpireChartGenerator into a Windows Forms control. It can be added to the Visual Studio toolbox and dropped into any Windows Forms application
Sample Application: Usenet Views
Usenet Views is a .NET Windows Forms application that displays Usenet statistics in a variety of graphical formats. The application's "Author Lines" view uses a SpireChartControl to show an author's Usenet activity over the course of a year. Here, for example, is one author's activity for 2002:
Each bubble represents a thread to which the author contributed. The red bubbles in the chart's upper half represent threads initiated by the author, while the blue bubbles in the lower half represent threads initiated by someone else. The size of each bubble is proportional to the number of posts the author made to the thread during the week.
Usenet Views is currently not available outside of Microsoft, but see the Netscan Web site for a related application.
How to Add a Spire Chart to Your Application
SpireChartGenerator and SpireChartControl are just two of the data visualization components that have been developed by the Microsoft Research Community Technologies team. See the Visualization Components overview for further information.
Questions and comments can be posted to the microsoft.public.research.netscan.discussion newsgroup.