Re-add rotationAngle property from v2 draft and clarify radius definition relative to it.
--- a/touchevents.html Mon Oct 28 10:35:43 2013 -0400
+++ b/touchevents.html Thu Jun 05 23:22:17 2014 -0400
@@ -560,6 +560,7 @@
<pre class="idl"><span class="idlInterface" id="idl-def-Touch">partial interface <span class="idlInterfaceID">Touch</span> {
<span class="idlAttribute"> readonly attribute <span class="idlAttrType">long</span> <span class="idlAttrName"><a href="#widl-Touch-radiusX">radiusX</a></span>;</span>
<span class="idlAttribute"> readonly attribute <span class="idlAttrType">long</span> <span class="idlAttrName"><a href="#widl-Touch-radiusY">radiusY</a></span>;</span>
+<span class="idlAttribute"> readonly attribute <span class="idlAttrType">float</span> <span class="idlAttrName"><a href="#widl-Touch-rotationAngle">rotationAngle</a></span>;</span>
<span class="idlAttribute"> readonly attribute <span class="idlAttrType">float</span> <span class="idlAttrName"><a href="#widl-Touch-force">force</a></span>;</span>
};</span></pre><section id="attributes"><h3 aria-level="2" role="heading" id="h3_attributes"><span class="secno">2.1 </span>Attributes</h3><dl class="attributes"><dt id="widl-Touch-force"><code>force</code> of type <span class="idlAttrType">float</span>, readonly </dt><dd>
a relative value of pressure applied, in the range <code>0</code> to
@@ -579,14 +580,29 @@
</p></div>
</dd><dt id="widl-Touch-radiusX"><code>radiusX</code> of type <span class="idlAttrType">long</span>, readonly </dt><dd>
the radius of the ellipse which most closely circumscribes the
- touching area (e.g. finger, stylus) along the x-axis, in CSS pixels of
+ touching area (e.g. finger, stylus) along the axis indicated by rotationAngle, in CSS pixels of
the same scale as screenX; <code>1</code> if no value is
known. The value must be positive.
</dd><dt id="widl-Touch-radiusY"><code>radiusY</code> of type <span class="idlAttrType">long</span>, readonly </dt><dd>
the radius of the ellipse which most closely circumscribes the
- touching area (e.g. finger, stylus) along the y-axis, in CSS pixels of
+ touching area (e.g. finger, stylus) along the axis perpendicular to that indicated by rotationAngle, in CSS pixels of
the same scale as screenY; <code>1</code> if no value is
known. The value must be positive.
+ </dd><dt id="widl-Touch-rotationAngle"><code>rotationAngle</code> of type <span class="idlAttrType">float</span>, readonly </dt><dd>
+ <p>
+ the angle (in degrees) that the ellipse described by <a>radiusX</a>
+ and <a>radiusY</a> is rotated clockwise about its center;
+ <code>0</code> if no value is known. The value must be greater
+ than or equal to <code>0</code> and less than <code>90</code>.
+ </p>
+ <p>
+ If the ellipse described by <a>radiusX</a> and <a>radiusY</a> is
+ circular, then <a>rotationAngle</a> has no effect. The user agent
+ may use <code>0</code> as the value in this case, or it may use any
+ other value in the allowed range. (For example, the user agent may
+ use the <a>rotationAngle</a> value from the previous touch event,
+ to avoid sudden changes.)
+ </p>
</dd></dl></section>
</section>