Non-standard: This feature is not standardized. We do not recommend using non-standard features in production, as they have limited browser support, and may change or be removed. However, they can be a suitable alternative in specific cases where no standard option exists.
The GestureEvent is a proprietary interface specific to WebKit which gives information regarding multi-touch gestures. Events using this interface include gesturestart, gesturechange, and gestureend.
This interface also inherits properties of its parents, UIEvent and Event.
GestureEvent.rotation Read only Change in rotation (in degrees) since the event's beginning. Positive values indicate clockwise rotation; negative values indicate counterclockwise rotation. Initial value: 0.0.
GestureEvent.scale Read only Distance between two digits since the event's beginning. Expressed as a floating-point multiple of the initial distance between the digits at the beginning of the gesture. Values below 1.0 indicate an inward pinch (zoom out). Values above 1.0 indicate an outward unpinch (zoom in). Initial value: 1.0.
This interface also inherits methods of its parents, UIEvent and Event.
GestureEvent.initGestureEvent() Initializes the value of a GestureEvent. If the event has already been dispatched, this method does nothing.
Not part of any specification. Apple has a description at the Safari Developer Library.