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Try to make the definitions of 'available', 'supported', image.width, image.height, and image.complete more correct. (whatwg r3126)

From: poot <cvsmail@w3.org>
Date: Tue, 26 May 2009 08:33:25 +0900 (JST)
To: public-html-diffs@w3.org
Message-Id: <20090525233325.954BC2BC4B@toro.w3.mag.keio.ac.jp>
Try to make the definitions of 'available', 'supported', image.width,
image.height, and image.complete more correct. (whatwg r3126)

Diffs for this change per section: 
http://people.w3.org/mike/diffs/html5/spec/Overview.1.2284.html#img-available
http://people.w3.org/mike/diffs/html5/spec/Overview.1.2284.html#text-that-has-been-rendered-to-a-graphic-for-typographical-effect
http://people.w3.org/mike/diffs/html5/spec/Overview.1.2284.html#attr-input-alt
http://people.w3.org/mike/diffs/html5/spec/Overview.1.2284.html#character-encodings
http://people.w3.org/mike/diffs/html5/spec/Overview.1.2284.html#a-short-phrase-or-label-with-an-alternative-graphical-representation:-icons-logos
http://people.w3.org/mike/diffs/html5/spec/Overview.1.2284.html#attr-img-alt
http://people.w3.org/mike/diffs/html5/spec/Overview.1.2284.html#input-img-available
http://people.w3.org/mike/diffs/html5/spec/Overview.1.2284.html#dom-img-complete
http://people.w3.org/mike/diffs/html5/spec/Overview.1.2284.html#conformance-requirements
http://people.w3.org/mike/diffs/html5/spec/Overview.1.2284.html#attr-input-src
http://people.w3.org/mike/diffs/html5/spec/Overview.1.2284.html#images-0
http://people.w3.org/mike/diffs/html5/spec/Overview.1.2284.html#resources
http://people.w3.org/mike/diffs/html5/spec/Overview.1.2284.html#dom-img-width

http://people.w3.org/mike/diffs/html5/spec/Overview.diff.html
http://dev.w3.org/cvsweb/html5/spec/Overview.html?r1=1.2283&r2=1.2284&f=h
http://html5.org/tools/web-apps-tracker?from=3125&to=3126

===================================================================
RCS file: /sources/public/html5/spec/Overview.html,v
retrieving revision 1.2283
retrieving revision 1.2284
diff -u -d -r1.2283 -r1.2284
--- Overview.html	25 May 2009 22:10:45 -0000	1.2283
+++ Overview.html	25 May 2009 23:31:43 -0000	1.2284
@@ -294,7 +294,8 @@
      <li><a href="#dom-trees"><span class="secno">2.1.2 </span>DOM trees</a></li>
      <li><a href="#scripting-0"><span class="secno">2.1.3 </span>Scripting</a></li>
      <li><a href="#plugins"><span class="secno">2.1.4 </span>Plugins</a></li>
-     <li><a href="#character-encodings"><span class="secno">2.1.5 </span>Character encodings</a></ol></li>
+     <li><a href="#character-encodings"><span class="secno">2.1.5 </span>Character encodings</a></li>
+     <li><a href="#resources"><span class="secno">2.1.6 </span>Resources</a></ol></li>
    <li><a href="#conformance-requirements"><span class="secno">2.2 </span>Conformance requirements</a>
     <ol>
      <li><a href="#dependencies"><span class="secno">2.2.1 </span>Dependencies</a></li>
@@ -1462,7 +1463,20 @@
   the set 0x09, 0x0A, 0x0C, 0x0D, 0x20 - 0x22, 0x26, 0x27, 0x2C -
   0x3F, 0x41 - 0x5A, and 0x61 - 0x7A<!-- is that list ok? do any
   character sets we want to support do things outside that range?
-  -->. <!-- XXX #refs RFC1345 ? --><h3 id="conformance-requirements"><span class="secno">2.2 </span>Conformance requirements</h3><p>All diagrams, examples, and notes in this specification are
+  -->. <!-- XXX #refs RFC1345 ? --><h4 id="resources"><span class="secno">2.1.6 </span>Resources</h4><p>The specification uses the term <i>supported</i> when referring
+  to whether a user agent has an implementation capable of decoding
+  the semantics of an external resource. A format or type is said to
+  be <i>supported</i> if the implementation can process an external
+  resource of that format or type without critical aspects of the
+  resource being ignored. Whether a specific resource is
+  <i>supported</i> can depend on what features of the resource's
+  format are in use.<p class="example">For example, a PNG image would be considered to
+  be in a supported format if its pixel data could be decoded and
+  rendered, even if, unbeknownst to the implementation, the image
+  actually also contained animation data.<p class="example">A MPEG4 video file would not be considered to be
+  in a supported format if the compression format used was not
+  supported, even if the implementation could determine the dimensions
+  of the movie from the file's metadata.<h3 id="conformance-requirements"><span class="secno">2.2 </span>Conformance requirements</h3><p>All diagrams, examples, and notes in this specification are
   non-normative, as are all sections explicitly marked non-normative.
   Everything else in this specification is normative.<p>The key words "MUST", "MUST NOT", "REQUIRED", <!--"SHALL", "SHALL
   NOT",--> "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and
@@ -15099,29 +15113,30 @@
   <a href="#origin-0" title="origin">cross-origin</a> access control policies
   that mitigate this attack.</p>
 
-  <p>If the image's type is a supported image type, and the image is a
-  valid image of that type, then the image is said to be
-  <i>available</i> (this affects exactly what the element represents,
-  as defined below). This can be true even before the image is
-  completely downloaded, if the user agent supports incremental
-  rendering of images; in such cases, each <a href="#concept-task" title="concept-task">task</a> that is <a href="#queue-a-task" title="queue a
+  <p>If the image is in a supported image type and its dimensions are
+  known, then the image is said to be <dfn id="img-available" title="img-available"><i>available</i></dfn> (this affects exactly
+  what the element represents, as defined below). This can be true
+  even before the image is completely downloaded, if the user agent
+  supports incremental rendering of images; in such cases, each <a href="#concept-task" title="concept-task">task</a> that is <a href="#queue-a-task" title="queue a
   task">queued</a> by the <a href="#networking-task-source">networking task source</a> while
   the image is being <a href="#fetch" title="fetch">fetched</a> must update
-  the presentation of the image appropriately.</p>
+  the presentation of the image appropriately. It can also stop being
+  true, e.g. if the user agent finds, after obtaining the image's
+  dimensions, that the image data is actually fatally corrupted.</p>
 
   <p>If the image was not fetched (e.g. because the UA's image support
   is disabled, or because the <code title="attr-img-src"><a href="#attr-img-src">src</a></code>
   attribute's value is an <i>ignored self-reference</i>), or if the
   conditions in the previous paragraph are not met, then the image is
-  <em>not</em> <i>available</i>.</p>
+  <em>not</em> <i title="img-available"><a href="#img-available">available</a></i>.</p>
 
-  <p class="note">An image might be <i>available</i> in one
-  <a href="#view">view</a> but not another. For instance, a
-  <code>Document</code> could be rendered by a screen reader providing
-  a speech synthesis view of the output of a Web browser using the
-  screen media. In this case, the image would be <i>available</i> in
-  the Web browser's screen view, but <em>not</em> <i>available</i> in
-  the screen reader's view.</p>
+  <p class="note">An image might be <i title="img-available"><a href="#img-available">available</a></i> in one <a href="#view">view</a> but not
+  another. For instance, a <code>Document</code> could be rendered by
+  a screen reader providing a speech synthesis view of the output of a
+  Web browser using the screen media. In this case, the image would be
+  <i title="img-available"><a href="#img-available">available</a></i> in the Web browser's screen
+  view, but <em>not</em> <i title="img-available"><a href="#img-available">available</a></i> in the
+  screen reader's view.</p>
 
   <p>Whether the image is fetched successfully or not (e.g. whether
   the response code was a 2xx code <a href="#concept-http-equivalent-codes" title="concept-http-equivalent-codes">or equivalent</a>) must be
@@ -15152,8 +15167,8 @@
 
   <p>The <a href="#concept-task" title="concept-task">task</a> that is <a href="#queue-a-task" title="queue a task">queued</a> by the <a href="#networking-task-source">networking task
   source</a> once the resource has been <a href="#fetch" title="fetch">fetched</a>, must, if the download was successful
-  and the image is <i>available</i>, <a href="#queue-a-task">queue a task</a> to
-  <a href="#fire-a-simple-event">fire a simple event</a> called <code title="event-load"><a href="#event-load">load</a></code> at the <code><a href="#the-img-element">img</a></code> element (this
+  and the image is <i title="img-available"><a href="#img-available">available</a></i>, <a href="#queue-a-task">queue
+  a task</a> to <a href="#fire-a-simple-event">fire a simple event</a> called <code title="event-load"><a href="#event-load">load</a></code> at the <code><a href="#the-img-element">img</a></code> element (this
   happens after <code title="dom-img-complete"><a href="#dom-img-complete">complete</a></code> starts
   returning true); and otherwise, if the fetching process fails
   without a response from the remote server, or completes but the
@@ -15176,8 +15191,8 @@
     the content, redundant with some other information in the
     document.</p>
 
-    <p>If the image is <i>available</i> and the user agent is
-    configured to display that image, then the element
+    <p>If the image is <i title="img-available"><a href="#img-available">available</a></i> and the
+    user agent is configured to display that image, then the element
     <a href="#represents">represents</a> the image specified by the <code title="attr-img-src"><a href="#attr-img-src">src</a></code> attribute.</p>
 
     <p>Otherwise, the element <a href="#represents">represents</a> nothing, and may
@@ -15196,8 +15211,8 @@
     <p>The image is a key part of the content; the <code title="attr-img-alt"><a href="#attr-img-alt">alt</a></code> attribute gives a textual
     equivalent or replacement for the image.</p>
 
-    <p>If the image is <i>available</i> and the user agent is
-    configured to display that image, then the element
+    <p>If the image is <i title="img-available"><a href="#img-available">available</a></i> and the
+    user agent is configured to display that image, then the element
     <a href="#represents">represents</a> the image specified by the <code title="attr-img-src"><a href="#attr-img-src">src</a></code> attribute.</p>
 
     <p>Otherwise, the element <a href="#represents">represents</a> the text given
@@ -15219,16 +15234,16 @@
     is a key part of the content but that a textual replacement for
     the image was not available when the image was generated.</p>
 
-    <p>If the image is <i>available</i>, the element
-    <a href="#represents">represents</a> the image specified by the <code title="attr-img-src"><a href="#attr-img-src">src</a></code> attribute.</p>
+    <p>If the image is <i title="img-available"><a href="#img-available">available</a></i>, the
+    element <a href="#represents">represents</a> the image specified by the <code title="attr-img-src"><a href="#attr-img-src">src</a></code> attribute.</p>
 
-    <p>If the image is not <i>available</i> or if the user agent is
-    not configured to display the image, then the user agent should
-    display some sort of indicator that there is an image that is not
-    being rendered, and may, if requested by the user, or if so
-    configured, or when required to provide contextual information in
-    response to navigation, provide caption information for the image,
-    derived as follows:</p>
+    <p>If the image is not <i title="img-available"><a href="#img-available">available</a></i> or
+    if the user agent is not configured to display the image, then the
+    user agent should display some sort of indicator that there is an
+    image that is not being rendered, and may, if requested by the
+    user, or if so configured, or when required to provide contextual
+    information in response to navigation, provide caption information
+    for the image, derived as follows:</p>
 
     <ol><li><p>If the image has a <code title="attr-title"><a href="#the-title-attribute">title</a></code>
      attribute whose value is not the empty string, then the value of
@@ -15346,17 +15361,18 @@
   rendered width and height of the image, in CSS pixels, if the image
   is being rendered, and is being rendered to a visual medium; or else
   the intrinsic width and height of the image, in CSS pixels, if the
-  image is <i>available</i> but not being rendered to a visual medium;
-  or else 0, if the image is not <i>available</i> or its dimensions
-  are not known. <a href="#references">[CSS21]</a></p>
+  image is <i title="img-available"><a href="#img-available">available</a></i> but not being
+  rendered to a visual medium; or else 0, if the image is not <i title="img-available"><a href="#img-available">available</a></i> or its dimensions are not
+  known. <a href="#references">[CSS21]</a></p>
 
   <p>On setting, they must act as if they <a href="#reflect" title="reflect">reflected</a> the respective content attributes
   of the same name.</p>
 
   <p>The DOM attribute <dfn id="dom-img-complete" title="dom-img-complete"><code>complete</code></dfn> must return
-  true if the user agent has fetched the image specified in the <code title="attr-img-src"><a href="#attr-img-src">src</a></code> attribute, and it is a valid image,
-  even if the final <a href="#concept-task" title="concept-task">task</a> queued by
-  the <a href="#networking-task-source">networking task source</a> for the <a href="#fetch" title="fetch">fetching</a> of the image resource has not yet been
+  true if the user agent has fetched the image specified in the <code title="attr-img-src"><a href="#attr-img-src">src</a></code> attribute, and it is in a supported
+  image type (i.e. it was decoded without fatal errors), even if the
+  final <a href="#concept-task" title="concept-task">task</a> queued by the
+  <a href="#networking-task-source">networking task source</a> for the <a href="#fetch" title="fetch">fetching</a> of the image resource has not yet been
   processed. Otherwise, the attribute must return false.</p>
 
   <p class="note">The value of <code title="dom-img-complete"><a href="#dom-img-complete">complete</a></code> can thus change while a
@@ -15679,9 +15695,9 @@
 at least that would look good on the cover of a blue book.&lt;/p&gt;</pre>
 
    <p>This example shows how the alternative text should be written
-   such that if the image isn't <i>available</i>, and the text is used
-   instead, the text flows seamlessly into the surrounding text, as
-   if the image had never been there in the first place.</p>
+   such that if the image isn't <i title="img-available"><a href="#img-available">available</a></i>, and the text is used instead,
+   the text flows seamlessly into the surrounding text, as if the
+   image had never been there in the first place.</p>
 
   </div><h6 id="text-that-has-been-rendered-to-a-graphic-for-typographical-effect"><span class="secno">4.8.2.1.4 </span>Text that has been rendered to a graphic for typographical effect</h6><p>Sometimes, an image just consists of text, and the purpose of the
   image is not to highlight the actual typographic effects used to
@@ -28803,12 +28819,11 @@
 
   <p>If the image was successfully obtained, with no network errors,
   and the image's type is a supported image type, and the image is a
-  valid image of that type, then the image is said to be
-  <i>available</i>. If this is true before the image is completely
-  downloaded, each <a href="#concept-task" title="concept-task">task</a> that is
-  <a href="#queue-a-task" title="queue a task">queued</a> by the <a href="#networking-task-source">networking
-  task source</a> while the image is being <a href="#fetch" title="fetch">fetched</a> must update the presentation of the
-  image appropriately.</p>
+  valid image of that type, then the image is said to be <dfn id="input-img-available" title="input-img-available"><i>available</i></dfn>. If this is true
+  before the image is completely downloaded, each <a href="#concept-task" title="concept-task">task</a> that is <a href="#queue-a-task" title="queue a
+  task">queued</a> by the <a href="#networking-task-source">networking task source</a> while
+  the image is being <a href="#fetch" title="fetch">fetched</a> must update
+  the presentation of the image appropriately.</p>
 
   <p>The user agents should apply the <a href="#content-type-sniffing:-image" title="Content-Type
   sniffing: image">image sniffing rules</a> to determine the type
@@ -28826,13 +28841,14 @@
 
   <p>The <a href="#concept-task" title="concept-task">task</a> that is <a href="#queue-a-task" title="queue a task">queued</a> by the <a href="#networking-task-source">networking task
   source</a> once the resource has been <a href="#fetch" title="fetch">fetched</a>, must, if the download was successful
-  and the image is <i>available</i>, <a href="#queue-a-task">queue a task</a> to
-  <a href="#fire-a-simple-event">fire a simple event</a> called <code title="event-load"><a href="#event-load">load</a></code> at the <code><a href="#the-input-element">input</a></code> element;
-  and otherwise, if the fetching process fails without a response from
-  the remote server, or completes but the image is not a valid or
-  supported image, <a href="#queue-a-task">queue a task</a> to <a href="#fire-a-simple-event">fire a simple
-  event</a> called <code title="event-error"><a href="#event-error">error</a></code> on the
-  <code><a href="#the-input-element">input</a></code> element.</p>
+  and the image is <i title="input-img-available"><a href="#input-img-available">available</a></i>,
+  <a href="#queue-a-task">queue a task</a> to <a href="#fire-a-simple-event">fire a simple event</a> called
+  <code title="event-load"><a href="#event-load">load</a></code> at the <code><a href="#the-input-element">input</a></code>
+  element; and otherwise, if the fetching process fails without a
+  response from the remote server, or completes but the image is not a
+  valid or supported image, <a href="#queue-a-task">queue a task</a> to <a href="#fire-a-simple-event">fire a
+  simple event</a> called <code title="event-error"><a href="#event-error">error</a></code> on
+  the <code><a href="#the-input-element">input</a></code> element.</p>
 
   <hr></div><p>The <dfn id="attr-input-alt" title="attr-input-alt"><code>alt</code></dfn> attribute
   provides the textual label for the alternative button for users and
@@ -28841,9 +28857,9 @@
   attributes</a>.<div class="impl">
 
   <hr><p>If the <code title="attr-input-src"><a href="#attr-input-src">src</a></code> attribute is set,
-  and the image is <i>available</i> and the user agent is configured
-  to display that image, then: The element <a href="#represents">represents</a> a
-  control for selecting a <a href="#concept-input-type-image-coordinate" title="concept-input-type-image-coordinate">coordinate</a> from
+  and the image is <i title="input-img-available"><a href="#input-img-available">available</a></i> and
+  the user agent is configured to display that image, then: The
+  element <a href="#represents">represents</a> a control for selecting a <a href="#concept-input-type-image-coordinate" title="concept-input-type-image-coordinate">coordinate</a> from
   the image specified by the <code title="attr-input-src"><a href="#attr-input-src">src</a></code>
   attribute; if the element is <i title="concept-input-mutable"><a href="#concept-input-mutable">mutable</a></i>, the user agent should
   allow the user to select this <a href="#concept-input-type-image-coordinate" title="concept-input-type-image-coordinate">coordinate</a>. The
@@ -62632,14 +62648,14 @@
   does not <a href="#represents" title="represents">represent</a> an image, but the
   element already has intrinsic dimensions (e.g. from the
   <a href="#dimension-attributes">dimension attributes</a> or CSS rules), and either the user
-  agent has reason to believe that the image will become
-  <i>available</i> and be rendered in due course or the
-  <code>Document</code> is in <a href="#quirks-mode">quirks mode</a>, the element is
-  expected to be treated as a replaced element whose content is the
-  text that the element represents, if any, optionally alongside an
-  icon indicating that the image is being obtained. For
-  <code><a href="#the-input-element">input</a></code> elements, the text is expected to appear
-  button-like to indicate that the element is a <a href="#concept-button" title="concept-button">button</a>.</p>
+  agent has reason to believe that the image will become <i title="img-available"><a href="#img-available">available</a></i><!--input-img-available also-->
+  and be rendered in due course or the <code>Document</code> is in
+  <a href="#quirks-mode">quirks mode</a>, the element is expected to be treated as a
+  replaced element whose content is the text that the element
+  represents, if any, optionally alongside an icon indicating that the
+  image is being obtained. For <code><a href="#the-input-element">input</a></code> elements, the text
+  is expected to appear button-like to indicate that the element is a
+  <a href="#concept-button" title="concept-button">button</a>.</p>
 
   <p>When an <code><a href="#the-img-element">img</a></code> element <a href="#represents">represents</a> some
   text and the user agent does not expect this to change, the element
Received on Monday, 25 May 2009 23:34:03 GMT

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