The Cascading Style Sheets (CSS) Working Group and the SVG Working Group have published a Last Call Working Draft of Compositing and Blending Level 1. Compositing describes how shapes of different elements are combined into a single image. There are various possible approaches for compositing. Previous versions of SVG used Simple Alpha Compositing. In this model, each element is rendered into its own buffer and is then merged with its backdrop using the Porter Duff source-over operator. This specification will define a new compositing model that expands upon the Simple Alpha Compositing model by offering additional Porter Duff compositing operators; advanced blending modes which allow control of how colors mix in the areas where shapes overlap; and compositing groups. Please send Last Call comments by 8 November 2013. Learn more about the Style Activity.