Drag to undo/redo a digital ink canvas using a visible history palette

Abstract

Techniques are described to support undo and redo operations in connection with a digital ink canvas on an appliance that can take part in a collaboration amongst multiple appliances that can share content. The digital ink canvas is a digital area that accepts inputs from a user and renders a digital stroke. The described techniques make use of a navigable history palette which includes individual history entries that each provide a visual representation of a state of the digital ink canvas at some point during the collaboration. The history palette provides a navigable user interface instrumentality which permits panning through the history palette to enable user to select a particular visual representation. The digital ink canvas is then returned to the state associated with the selected visual representation. The selected visual representation can be provided across the appliances participating in the virtual collaboration.