[css-grid] Define the static position of absposes in a grid, per task force discussion.

Author: tabatkins

css-grid/Overview.html

@@ -42,7 +42,7 @@
 </a></p>
   <h1 class="p-name no-ref" id=title>CSS Grid Layout Module Level 1</h1>
   <h2 class="no-num no-toc no-ref" id=subtitle><span class=content>Editor's Draft,
-    <span class=dt-updated><span class=value-title title=20130823>23 August 2013</span></span></span></h2>
+    <span class=dt-updated><span class=value-title title=20130826>26 August 2013</span></span></span></h2>
   <div data-fill-with=spec-metadata><dl><dt>This version:<dd><a class=u-url href=http://dev.w3.org/csswg/css-grid/>http://dev.w3.org/csswg/css-grid/</a><dt>Latest version:<dd><a href=http://www.w3.org/TR/css3-grid-layout/>http://www.w3.org/TR/css3-grid-layout/</a><dt>Editor's Draft:<dd><a href=http://dev.w3.org/csswg/css-grid/>http://dev.w3.org/csswg/css-grid/</a>
 <dt>Feedback:</dt>
     <dd><a href="mailto:www-style@w3.org?subject=%5Bcss-grid%5D%20feedback">www-style@w3.org</a>
@@ -761,19 +761,18 @@ <h3 data-level=4.1 id=abspos-items><span class=secno>4.1 </span><span class=cont
 
 	<p>
 		An absolutely-positioned child element of a <a href=#grid-container>grid container</a> does not participate directly in grid layout.
-		Its static position is ???
-
-	<p class=issue>
-		The static position is affected by the alignment properties, 
-		as if it was a 0x0 thing floating around in the <a>containing block</a>.
-		(Defaults to the start/start corner, since <span class=css data-link-type=maybe>stretch</span> can't do anything to it.)
+		Its static position is affected by the values of <a class=property data-link-type=propdesc href=http://dev.w3.org/csswg/css-align-3/#justify-self title=justify-self>justify-self</a> and <a class=property data-link-type=propdesc href=http://dev.w3.org/csswg/css-align-3/#align-self title=align-self>align-self</a> on it,
+		using the <a href=#grid-container>grid container</a>’s padding box as the <a href=http://dev.w3.org/csswg/css-align-3/#alignment-container>alignment container</a>
+		and the element’s own box as the <a href=http://dev.w3.org/csswg/css-align-3/#alignment-container>alignment container</a>.
+		A <span class=css data-link-type=maybe>baseline</span> value for either <a class=property data-link-type=propdesc href=http://dev.w3.org/csswg/css-align-3/#justify-self title=justify-self>justify-self</a> or <a class=property data-link-type=propdesc href=http://dev.w3.org/csswg/css-align-3/#align-self title=align-self>align-self</a> is treated as <a class=css data-link-type=maybe href=http://dev.w3.org/csswg/css-writing-modes-3/#start>start</a> for these purposes.
 
 	<p>
 		If an absolutely positioned element's <a>containing block</a>
 		is generated by a <a href=#grid-container>grid container</a>,
 		the <a href=#grid-placement-properties>grid-placement properties</a> can be used to constrain it to a particular <a href=#grid-area>grid area</a>,
 		similar to how they affect regular <a href=#grid-item>grid items</a>.
-		In this case, an <a data-link-for="<grid-line>" data-link-type=value href=#grid-placement-auto>auto</a> value for a <a href=#grid-placement-properties>grid-placement property</a> indicates the corresponding padding edge of the <a href=#grid-container>grid container</a>.
+		In this case, an <a data-link-for="<grid-line>" data-link-type=value href=#grid-placement-auto>auto</a> value for a <a href=#grid-placement-properties>grid-placement property</a> 
+		indicates the corresponding padding edge of the <a href=#grid-container>grid container</a>.
 
 	<p class=note>
 		Absolute positioning can allow an element to “skip past” intervening grid containers,

css-grid/Overview.src.html

@@ -16,7 +16,7 @@ <h1>CSS Grid Layout Module Level 1</h1>
 Issues list: <a href="https://www.w3.org/Bugs/Public/buglist.cgi?product=CSS&amp;component=Grid+Layout&amp;bug_status=NEW&amp;bug_status=ASSIGNED&amp;bug_status=REOPENED">In Bugzilla</a>
 Abstract: This CSS module defines a two-dimensional grid-based layout system, optimized for user interface design. In the grid layout model, the children of a grid container can be positioned into arbitrary slots in a flexible or fixed predefined layout grid.
 Ignored Terms: column-*, justify-*, containing block, grid-field, <positive-integer>, <ident>, auto
-Link Defaults: css21 (property) margin
+Link Defaults: css21 (property) margin, css-align-3 (dfn) alignment container/alignment subject
 </pre>
 
 <style type="text/css">
@@ -675,19 +675,18 @@ <h3 id="abspos-items">
 
 	<p>
 		An absolutely-positioned child element of a <a>grid container</a> does not participate directly in grid layout.
-		Its static position is ???
-
-	<p class='issue'>
-		The static position is affected by the alignment properties, 
-		as if it was a 0x0 thing floating around in the <a>containing block</a>.
-		(Defaults to the start/start corner, since ''stretch'' can't do anything to it.)
+		Its static position is affected by the values of 'justify-self' and 'align-self' on it,
+		using the <a>grid container</a>’s padding box as the <a>alignment container</a>
+		and the element’s own box as the <a>alignment container</a>.
+		A ''baseline'' value for either 'justify-self' or 'align-self' is treated as ''start'' for these purposes.
 
 	<p>
 		If an absolutely positioned element's <a>containing block</a>
 		is generated by a <a>grid container</a>,
 		the <a>grid-placement properties</a> can be used to constrain it to a particular <a>grid area</a>,
 		similar to how they affect regular <a>grid items</a>.
-		In this case, an <a value for="<grid-line>">auto</a> value for a <a>grid-placement property</a> indicates the corresponding padding edge of the <a>grid container</a>.
+		In this case, an <a value for="<grid-line>">auto</a> value for a <a>grid-placement property</a> 
+		indicates the corresponding padding edge of the <a>grid container</a>.
 
 	<p class='note'>
 		Absolute positioning can allow an element to “skip past” intervening grid containers,