Overview.src.html

Author: fantasai

css3-background/Overview.html

@@ -22,12 +22,12 @@
 
    <h1>CSS Backgrounds and Borders Module Level 3</h1>
 
-   <h2 class="no-num no-toc" id=longstatus-date>Editor's Draft 28 April 2010</h2>
+   <h2 class="no-num no-toc" id=longstatus-date>Editor's Draft 5 May 2010</h2>
 
    <dl>
     <dt>This version:
 
-    <dd><!--<a href="http://www.w3.org/TR/2010/WD-css3-background-20100428">http://www.w3.org/TR/2010/ED-css3-background-20100428</a>-->
+    <dd><!--<a href="http://www.w3.org/TR/2010/WD-css3-background-20100505">http://www.w3.org/TR/2010/ED-css3-background-20100505</a>-->
      <a
      href="http://dev.w3.org/csswg/css3-background">http://dev.w3.org/csswg/css3-background</a>
 
@@ -3704,14 +3704,27 @@ <h3 id=the-box-shadow><span class=secno>6.2. </span>The &lsquo;<a
    <li>The second length is the vertical offset. A positive value offsets the
     shadow down, a negative one up.
 
-   <li>The third length is a blur radius. Negative values are not allowed. If
-    it is 0, the shadow is sharp, otherwise the larger the value, the more
-    the shadow is blurred. The exact algorithm is not specified.
+   <li>The third length is a blur radius. Negative values are not allowed.
+    The blur radius is perpendicular to and centered on the shadow's edge and
+    defines a gradient color transition ranging from the full shadow color at
+    the radius endpoint inside the shadow to fully transparent at the
+    endpoint outside it: if the blur radius is 0, the shadow's edge is sharp,
+    otherwise the larger the value, the more the shadow is blurred. The exact
+    algorithm for the blur transition is not specified.
 
    <li>The fourth length is a spread radius. Positive values cause the shadow
-    to grow in all directions by the specified radius. Negative values cause
-    the shadow to shrink. The shadow should not change shape when a spread
-    radius is applied: sharp corners should remain sharp.
+    shape to expand in all directions by the specified radius. Negative
+    values cause the shadow shape to contract. For corners with a zero
+    border-radius, the corner remains sharp. Otherwise the spread radius
+    outsets the edge of the shadow by the amount of the spread radius in the
+    direction perpendicular to the shadow's edge. <span class=note>Note that
+    for inner shadows, expanding the shadow means shrinking the shadow's
+    perimeter.</span> The UA may approximate the spread shape by outsetting
+    (insetting, for inner shadows) the shadow's straight edges by the spread
+    radius and increasing (decreasing, for inner shadows) and flooring at
+    zero the corner radii by the same amount. If both a blur radius and a
+    spread radius are defined, the blur is applied to the resulting shape
+    after the spread is applied.
 
    <li>The color is the color of the shadow.
 

css3-background/Overview.src.html

@@ -2681,15 +2681,30 @@ <h3 id="the-box-shadow">The 'box-shadow' property</h3>
   offsets the shadow down, a negative one up.
 
   <li>The third length is a blur radius. Negative values are not
-  allowed. If it is 0, the shadow is sharp, otherwise the larger the
-  value, the more the shadow is blurred. The exact algorithm is not
-  specified.
+  allowed. The blur radius is perpendicular to and centered on the
+  shadow's edge and defines a gradient color transition ranging from
+  the full shadow color at the radius endpoint inside the shadow to
+  fully transparent at the endpoint outside it: if the blur radius
+  is 0, the shadow's edge is sharp, otherwise the larger the value,
+  the more the shadow is blurred. The exact algorithm for the blur
+  transition is not specified.
 
   <li>The fourth length is a spread radius. Positive values cause
-  the shadow to grow in all directions by the specified radius.
-  Negative values cause the shadow to shrink. The shadow should not
-  change shape when a spread radius is applied: sharp corners should
-  remain sharp.
+  the shadow shape to expand in all directions by the specified
+  radius. Negative values cause the shadow shape to contract. For
+  corners with a zero border-radius, the corner remains sharp.
+  Otherwise the spread radius outsets the edge of the shadow by
+  the amount of the spread radius in the direction perpendicular
+  to the shadow's edge.
+  <span class="note">Note that for inner shadows, expanding the
+  shadow means shrinking the shadow's perimeter.</span>
+  The UA may approximate the spread shape by outsetting (insetting,
+  for inner shadows) the shadow's straight edges by the spread
+  radius and increasing (decreasing, for inner shadows) and
+  flooring at zero the corner radii by the same amount.
+
+  If both a blur radius and a spread radius are defined, the blur
+  is applied to the resulting shape after the spread is applied.
 
   <li>The color is the color of the shadow.