Touch-based annotation system with temporary modes

摘要

One embodiment provides a system for processing gesture inputs on a touch screen display. The system receives a gesture input on the touch screen display. When the gesture is recognized as invoking an annotation canvas, the system determines the height, width and location of an annotation canvas, and displays the annotation canvas on the touch screen display. Then, in response to an input gesture within the annotation canvas, the system recognizes the gesture as an annotation gesture, and executes the annotation gesture. In response to receiving an input gesture outside of the annotation canvas, the gesture is interpreted by the system as a navigation input.