GeoSite and GeoSVG

GeoSVG: A Dynamic Geometry Authoring Tool Written in SVG and Javascript Providing most of the capabilities of a traditional Dynamic Geometry System (DGS) Inherent web-oriented –What GeoSVG generates automatically can be viewed and manipulated online –The entire GeoSVG authoring tool is online –User does NOT need to install software and compose web pages –Server Geosite provides File open, File edit, and File save for GeoSVG.

What a DGS should be able to do Dynamic geometric object construction and manipulation (All mathematical relations are preserved while objects are being dragged by mouse or values are changing) Transformation of geometric objects (Translate, Rotate, Dilate, and Reflect) Measurement Animation Calculation (A dynamic calculator) Analytic Geometry (Plotting functions, coordinate systems) Locus (a totality of all points, satisfying the certain given conditions) Iteration (Geometric iteration and numerical iteration) Script/Macro (A sequence of steps that can be defined as a new function)

Current status of GeoSVG Initial design closely followed Geometer’s SketchPad Disadvantages of initial design: –Basic building blocks are too primitive (point/circle/line) –SketchPad is not able to generate most of the manipulatives in WME pilot site –Even a manipulative can be generated, user may have to create tens or hundreds of hidden objects. Current Design will provide more native support for high-level objects such as geometric shapes

GeoSite: Server-side support for GeoSVG Logged-in user can create unlimited levels of folders under his/her account and store manipulative under any folder (implemented by MySQL) Users can create new manipulative, edit existing manipulative or delete a manipulative. Users can share manipulative across the entire GeoSite –Link or copy other user’s manipulative –Access control can be defined –Search A user who doesn’t log in can only view/manipulate manipulative Manipulative can be embedded in pages outside GeoSite

Three phases of a manipulative GeoSite invokes different environments for three phases of a manipulative: author, configure, and view/manipulate –Disadvantage of traditional DGS Authoring phase (invoked by new or edit): the entire GeoSVG authoring environment will be provided Configuring phase (invoked by configure): Each object in a manipulative has some public interface. The configuring page will list all the configurable parameters for tuning for users who doesn’t want to use the authoring environment. –configuration example pageconfiguration example page Viewing/Manipulating phase: All the menus and buttons in the authoring environment are NOT provided. –An author can export a menu function as a button to extend the capability of the viewing environment.

Submission-type Manipulative How: An author exports a submit button during authoring Any user including guest can manipulate the submission-type manipulative and hit the submit button. The submission will be saved back to the GeoSite. The owner of the submission-type manipulative can check all the submissions.

Implementation of submitting a drawing to GeoSite Both the editing of a manipulative or submission of a submission-type manipulative need to save the manipulative back to the server GeoSite Current implementation uses inter-document communication (xhtml-svg), then submits a xhtml form to the server. –Only works under Windows/IE due to the inter-document communication problem Future implementation uses getURL() and postURL provided by Adobe SVG Viewer. –Works under Windows/IE/Mozilla, Unix/Mozilla, Mac(?) –Example Example2ExampleExample2

Server Connection Example getURL( “URL”, callback); function callback( urlRequestStatus ) { if ( urlRequestStatus.success ) { xmldoc=parseXML( urlRequestStatus.content ).documentElement; } else { alert(“Error!"); }

More on GeoSite Define access control of folders and manipulatives –Private, viewable, copyable / friend, group, anybody –Password protected –Who can submit the submission-type manipulative Search Possibility of interaction between WME sites and GeoSite Mostly important, a good GeoSVG should be developed before a good GeoSite.

Advantages of GeoSite and GeoSVG over Traditional DGS Users don’t have to install software A manipulative constructed by a user can be viewed immediately by other users GeoSite provides a bank of manipulatives. A teachers can quickly find a manipulative he/she wants. Submission-type manipulatives enable students to answer questions in graphics. –Submission of a drawing is also useful in Assessment for teachers to author questions with graphics