michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "nsIDOMEvent.idl"
michael@0: 
michael@0: [scriptable, builtinclass, uuid(f5921a77-3ac5-4374-bc0c-1ed52fe83123)]
michael@0: interface nsIDOMDeviceOrientationEvent : nsIDOMEvent
michael@0: {
michael@0:   void initDeviceOrientationEvent(in DOMString eventTypeArg,
michael@0:                                   in boolean canBubbleArg,
michael@0:                                   in boolean cancelableArg,
michael@0:                                   in double alpha,
michael@0:                                   in double beta,
michael@0:                                   in double gamma,
michael@0:                                   in boolean absolute);
michael@0: 
michael@0:   /*
michael@0:    * W3C specification values: http://dev.w3.org/geo/api/spec-source-orientation.html
michael@0:    *
michael@0:    * Alpha, beta and gamma are Tait-Bryan angles (Z-X'-Y''), that is they correspond to
michael@0:    * yaw, pitch and roll in flight coordinates. More specifically, assume the device
michael@0:    * is resting face up on a flat surface (its screen is pointing straight up). Then
michael@0:    * the X axis points to the right when looking at the screen, the Y axis points up
michael@0:    * when looking at the screen, and the Z axis points toward you when looking at
michael@0:    * the screen. Alpha/beta/gamma then define the device's orientation by applying
michael@0:    * the following rotations to the device in order:
michael@0:    *
michael@0:    * 1) Rotate it by alpha degrees around its Z axis (like a compass, or like changing
michael@0:    *    the yaw of an aircraft, assuming the Y axis is the nose of the craft); alpha
michael@0:    *    is in [0,360).
michael@0:    * 2) Rotate it by beta degrees around its X axis (tilting the top of the device
michael@0:    *    towards or away from you, like pitching an aircraft); beta is in [-180,180).
michael@0:    * 3) Rotate it by gamma degrees around its Y axis (tilting it sideways, like
michael@0:    *    rolling an aircraft); gamma is in [-90,90).
michael@0:    */
michael@0: 
michael@0:   readonly attribute double alpha;
michael@0:   readonly attribute double beta;
michael@0:   readonly attribute double gamma;
michael@0:   readonly attribute boolean absolute;
michael@0: };