I will present google_chart_tools, a Drupal module for data visualization. It is used for creating rich interactive charts. It uses Google Chart Tools (GCT), a Javascript API, for creating charts in SVG (Scalable Vector Graphics). I will present code for creating built-in charts--LineChart, PieChart, ColumnChart, GeoChart and others. Next, I will describe coding of interactivity and animation features of GCT.

I will describe a project in which we customized the GCT module to create custom charts and custom chart features. The project involved creating a custom DB specifically for data visualization. We used forms API to create forms to input various configuration parameters. I will present, a new chart type, polar charts. This is created by modifying the GCT module. Other enhancements to the module are done to meet our need for displaying custom circles, lines and text in background of a line chart. This is accomplished by modifying the module to take as input “raw” SVG elements, which are then added to chart’s SVG DOM.

Google Chart Tools is a very good option for presenting data as rich interactive charts.