Enhancing Web Sketchpad

As a longtime Sketchpad fan, one of the most interesting features of Web Sketchpad (WSP) for me is the way its behavior can be customized. WSP makes it possible to add JavaScript to a web page in order to interact directly with objects in the sketch. For instance, a JavaScript function could use the locations of three points in a sketch to calculate whether or not they are vertices of an equilateral triangle. A different function could be used to listen for a specific event in a sketch such as a point being dragged, a tool being used,  a new page being shown, or a sketch object being tapped.

I’ve had the opportunity recently to write some JavaScript that allows students to tap an object to change its color, style, or visibility. You can try it out using the websketch below (or here on its own page). Tap the visibility widget (visibility icon) to hide or show objects in the sketch. Tap the style widget (style icon) to change the styles and colors of objects in the sketch.

Once you activate the visibility widget (visibility icon), tap any object in the sketch to change its visibility; your changes will take effect when you tap the widget again. (You can still drag and even construct objects normally; the widget responds only to taps.) After you tap the style widget (style icon), you can choose a style from one of the panes that appear and then tap objects in the sketch to change their styles and colors.

Page 1 contains a sample construction of a square; your task is to figure out how it was made. Use the remaining pages to create your own ways of constructing a square, different from the method on page 1. Use object styles, colors, and visibility to distinguish between construction lines and the sides of the finished square. See our earlier blog post to view a short movie demonstrating how the various construction tools work.

As you try out these widgets, I’d love to hear your thoughts about how they work. I tried to make them simple to figure out and easy to use, but they remain a work in progress and I’d love to hear your suggestions for improving them. (Also let us know about other enhancements you’d like to see implemented.)

In creating this format controller, the support of folks at McGraw-Hill Education has been invaluable: WSP developers Matt Litwin, Lyn Headly, and Raymond Cheung; product manager Bryan Corwin; and my long-time colleague and good friend Daniel Scher.

(If you own Sketchpad and would like to try out Web Sketchpad for your own non-commercial purposes, email dscher at kcptech dot com for information about the current beta test. We’re particularly interested in your experiences using WSP with your students.)

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