Add tangential pressure

index.html

@@ -263,6 +263,10 @@ <h2><code>PointerEvent</code> Interface</h2>
                         <dd>
                             The normalized pressure of the pointer input in the range of [0,1], where 0 and 1 represent the minimum and maximum pressure the hardware is capable of detecting, respectively. For hardware that does not support pressure, the value MUST be 0.5 when in the <a>active buttons state</a> and 0 otherwise.
                         </dd>
+                    <dt>readonly attribute float tangentialPressure</dt>
+                        <dd>
+                          The normalized tangential pressure (also known as barrel pressure), typically set by an additional control (e.g. a finger wheel on an airbrush stylus), of the pointer input in the range of [-1,1], where 0 is the neutral position of the control. Note that some hardware may only support positive values in the range of [0,1]. For hardware that does not support tangential pressure, the value MUST be 0.
+                        </dd>
                     <dt>readonly attribute long tiltX</dt>
                         <dd>
                             <p>The plane angle (in degrees, in the range of [-90,90]) between the Y-Z plane and the plane containing both the transducer (e.g. pen stylus) axis and the Y axis. A positive <code>tiltX</code> is to the right. <code>tiltX</code> can be used along with <code>tiltY</code> to represent the tilt away from the normal of a transducer with the digitizer. For devices that do not report tilt, the value MUST be 0.</p>
@@ -313,6 +317,8 @@ <h2><code>PointerEvent</code> Interface</h2>
                         <dd>Initializes the <code>height</code> property of the <code>PointerEvent</code> object.</dd>
                     <dt>float pressure = 0</dt>
                         <dd>Initializes the <code>pressure</code> property of the <code>PointerEvent</code> object.</dd>
+                    <dt>float tangentialPressure = 0</dt>
+                        <dd>Initializes the <code>tangentialPressure</code> property of the <code>PointerEvent</code> object.</dd>
                     <dt>long tiltX = 0</dt>
                         <dd>Initializes the <code>tiltX</code> property of the <code>PointerEvent</code> object.</dd>
                     <dt>long tiltY = 0</dt>
@@ -536,7 +542,7 @@ <h3><dfn>The <code>pointerdown</code> event</dfn></h3>
             </section>
             <section>
                 <h3><dfn>The <code>pointermove</code> event</dfn></h3>
-                <p>A user agent MUST <a href="#firing-events-using-the-pointerevent-interface">fire a pointer event</a> named <code>pointermove</code> when a pointer changes coordinates. Additionally, when a pointer changes button state, pressure, tilt, twist, or contact geometry (e.g. <code>width</code> and <code>height</code>) and the circumstances produce no other pointer events defined in this specification then a user agent MUST <a href="#firing-events-using-the-pointerevent-interface">fire a pointer event</a> named <code>pointermove</code>.</p>
+                <p>A user agent MUST <a href="#firing-events-using-the-pointerevent-interface">fire a pointer event</a> named <code>pointermove</code> when a pointer changes coordinates. Additionally, when a pointer changes button state, pressure, tangential pressure, tilt, twist, or contact geometry (e.g. <code>width</code> and <code>height</code>) and the circumstances produce no other pointer events defined in this specification then a user agent MUST <a href="#firing-events-using-the-pointerevent-interface">fire a pointer event</a> named <code>pointermove</code>.</p>
             </section>
             <section>
                 <h3><dfn>The <code>pointerup</code> event</dfn></h3>
@@ -931,6 +937,7 @@ <h1>Revision History</h1>
         <p>The following is an informative summary of substantial and major editorial changes between publications of this specification, relative to the first [[PointerEvents]] specification. See the <a href="https://github.com/w3c/pointerevents/commits">complete revision history of the Editor's Drafts of this specification</a>.</p>
         <h3>Changes since the 24 February 2015 Recommendation</h3>
         <ul>
+            <li><a href="https://github.com/w3c/pointerevents/pull/87">Add digitizer/pen tangential (barrel) pressure</a></li>
             <li><a href="https://github.com/w3c/pointerevents/pull/79">Add digitizer/pen twist</a></li>
             <li><a href="https://github.com/w3c/pointerevents/pull/69">Make width/height default to 1, remove UA "guessing"/faking geometry</a></li>
             <li><a href="https://github.com/w3c/pointerevents/pull/56">Made mouseover/out/enter/leave event firing independent of corresponding PEs</a></li>