Misc edits to animation model section

Author: birtles

web-animations/img/animation-cascade.svg

@@ -3220,12 +3220,6 @@ <h2>Animation effects</h2>
         Since the result of an <a>animation effect</a> is based on the
         <a>time fraction</a> and <a>current iteration</a> value, it is updated
         whenever the timing model is <a title="sampling">sampled</a>.
-        Note that changes to the timing model caused by using the <a
-        href="#programming-interface">programming interface</a> do <em>not</em>
-        cause the animation model (and hence <a>animation effects</a>) to be
-        updated as described in <a
-        href="#script-execution-and-live-updates-to-the-model"
-        class="sectionRef"></a>.
       </p>
       <section>
         <h3>Target properties</h3>
@@ -3236,8 +3230,8 @@ <h3>Target properties</h3>
           <a title="target property">Target properties</a> may be CSS properties
           or DOM attributes.
           If a given <a>animation target</a> has an attribute with the same name
-          as a CSS property, any <a>target property</a> is taken to refer to to
-          the CSS property.
+          as a CSS property, any <a>target property</a> of that name is taken to
+          refer to to the CSS property.
         </p>
         <p class="note">
           If there ever exists a situation where we need to animate an attribute
@@ -3251,7 +3245,7 @@ <h3>Target properties</h3>
       <section>
         <h3>Procedures for animating properties</h3>
         <p>
-          In order to animate a <a>target property</a> the following procedures
+          In order to animate a <a>target property</a>, the following procedures
           must be defined.
         </p>
         <ul>
@@ -3275,11 +3269,22 @@ <h3>Procedures for animating properties</h3>
               multiplication) <var>V</var><sub>a</sub> represents the first term
               of the operation and <var>V</var><sub>b</sub> represents the
               second.
+              <div class="informative">
+                <p>
+                  While <a title="animation addition">addition</a> can often be
+                  expressed in terms of the same weighted sum function used to
+                  define <a title="animation interpolation">interpolation</a>,
+                  this is not always the case.
+                  For example, interpolation of transform matrices involves
+                  decomposing and interpolating the matrix components whilst
+                  addition relies on matrix multiplication.
+                </p>
+              </div>
           <li><dfn title="animation accumulation">accumulation</dfn> &mdash;
               given two target property values
               <var>V</var><sub>a</sub> and <var>V</var><sub>b</sub>, returns the
               result, <var>V</var><sub>result</sub>, of combining
-              the two operands such that <var>V</var><sub>b</sub> represents
+              the two operands such that <var>V</var><sub>b</sub> is treated as
               a <em>delta</em> from <var>V</var><sub>a</sub>.
               For accumulation that is not commutative (for example,
               accumulation of mismatched transform lists)
@@ -3306,18 +3311,9 @@ <h3>Procedures for animating properties</h3>
               </div>
           <li><dfn>distance computation</dfn> &mdash; given two target property
               values <var>V</var><sub>start</sub> and
-              <var>V</var><sub>end</sub> calculates some notion of scalar
+              <var>V</var><sub>end</sub>, calculates some notion of scalar
               distance between the values, <var>distance</var>.
         </ul>
-        <p class="note">
-          While <a title="animation addition">addition</a> can often be
-          expressed in terms of the same weighted sum function used to define <a
-          title="animation interpolation">interpolation</a>, this is not always
-          the case.
-          For example, interpolation of transform matrices involves
-          decomposing and interpolating the matrix components whilst addition
-          relies on matrix multiplication.
-        </p>
       </section>
       <section>
         <h3>Specific animation behaviors</h3>
@@ -3388,7 +3384,8 @@ <h4>Not animatable</h4>
             An <a>animation effect</a> that targets a property that is
             <a>not animatable</a> will still exhibit the usual behavior for
             a <a>timed item</a> such as occupying time in an <a>animation
-            sequence</a>.
+            sequence</a> and delaying the firing of a <a>player</a>'s <a
+            title="finish player event">finish event</a>.
           </p>
         </section>
         <section>
@@ -3689,24 +3686,20 @@ <h3>Intermediate animation values</h3>
           <a>underlying value</a>, an <a>animation effect</a> produces
           an <dfn>intermediate animation value</dfn> for each <a>animatable</a>
           <a>target property</a>.
-          Before being applied to the <a title="target property">target
-          properties</a>,
-          these <a>intermediate animation values</a> are composed together using
-          the process defined in <a href="#combining-animations"
-          class="sectionRef"></a>.
-        </p>
-        <p>
-          An <a>intermediate animation value</a> is the result of
-          evaluating an <a>animation effect</a> for a given <a>target
-          property</a>, <a>time fraction</a>, <a>current iteration</a>,
-          and <a>underlying value</a>.
           The procedure for calculating this value depends on the specific
           type of <a>animation effect</a> and is defined subsequently (see <a
           href="#the-intermediate-animation-value-of-a-keyframe-animation-effect"
           class="sectionRef"></a> and <a
           href="#the-intermediate-animation-value-of-a-motion-path-animation-effect"
           class="sectionRef"></a>).
         </p>
+        <p>
+          Before being applied to the <a title="target property">target
+          properties</a>,
+          these <a>intermediate animation values</a> are composed together using
+          the process defined in <a href="#combining-animations"
+          class="sectionRef"></a>.
+        </p>
       </section>
     </section>
 
@@ -3715,7 +3708,7 @@ <h2>Combining animations</h2>
       <div class="informative">
         <p>
           After calculating the <a>intermediate animation values</a> for an
-          <a>animation effect</a> they are applied to the <a>animation
+          <a>animation effect</a>, they are applied to the <a>animation
           effect</a>'s <a title="target property">target properties</a>.
         </p>
         <p>
@@ -3750,7 +3743,7 @@ <h2>Combining animations</h2>
           <code>!important</code> rules.
         </p>
         <p>
-          For <a>target property</a> that specifies a DOM attribute, the
+          For a <a>target property</a> that specifies a DOM attribute, the
           composited result is combined with the value of the attribute
           specified in the DOM or the lacuna value for that attribute if it is
           not specified.