[css-gaps-1][editorial] Merge the gap decoration segment algorithms

Author: kbabbitt

css-gaps-1/Overview.bs

@@ -361,10 +361,10 @@ Gap decoration segments</h4>
 	Algorithms</h5>
 
 	<div algorithm>
-		To <dfn>determine the gap decoration segments</dfn> for a given [=gap=] |G|:
+		To <dfn>determine gap decoration segments</dfn> for a given [=gap=] |G|:
 		<ol>
 			<li>
-				Let |S|, the collection of [=gap decoration segments=] for |G|, be an empty list.
+				Let |S| be an empty list.
 			</li>
 			<li>
 				Let |endpoints| be the result of [=creating segment endpoints=] for |G|,
@@ -374,58 +374,41 @@ Gap decoration segments</h4>
 				between [=start segment endpoint=] and [=end segment endpoint=], beginning with a [=start segment endpoint=].
 			</li>
 			<li>
-				While |endpoints| is not empty:
-				<ul>
-					<li>Let |u| be the first [=segment endpoint=] in |endpoints|, and remove it from the list.</li>
-					<li>Let |v| be the first [=segment endpoint=] in |endpoints|, and remove it from the list.</li>
-					<li>Create a new [=gap decoration segment=] starting at |u| and ending at |v|.</li>
-					<li>Append the new segment to |S|.</li>
-				</ul>
+				If |endpoints| is empty, return |S|.
 			</li>
 			<li>
-				Return |S|.
+				Let |break| be the used value of either 'column-rule-break' or 'row-rule-break', whichever applies to the gap.
 			</li>
-		</ol>
-
-	</div>
-
-	<div algorithm>
-		To <dfn>determine painted segments</dfn> |C| from segments list |S|:
-
-		<ol>
-			<li>Let |S| be the list of segments <a lt="determine the gap decoration segments">determined</a> for the given gap, ordered from start to end along the gap's axis.
-			<li>Let |C| be an empty list of segments.
-			<li>Let |break| be the used value of either 'column-rule-break' or 'row-rule-break', whichever applies to the gap.
-
-			<li>If |S| is empty, return |C|.
-
 			<li>If |break| is ''column-rule-break/none'':
 				<ol>
-					<li>Let |first| be the first segment in |S|.
-					<li>Let |last| be the last segment in |S|.
-					<li>Let |segment| be [=UNION=](|first|, |last|).
-					<li>[=Apply offsets to a segment|Apply offsets to=] |segment|, then append it to |C|.
-					<li>Return |C|.
+					<li>Let |first| be the first item in |endpoints|.
+					<li>Let |last| be the last item in |endpoints|.
+					<li>Create a [=gap decoration segment=] |segment| = [|first|, |last|].
+					<li>[=Apply offsets to a segment|Apply offsets to=] |segment|, then append it to |S|.
+					<li>Return |S|.
 				</ol>
+			</li>
+
+			<li><em>Empty Check:</em> If |endpoints| is empty, return |S|.
 
-			<li>Remove the first segment from |S|. Let |s| be that segment.
+			<li>Create a [=gap decoration segment=] |s| from the first two items in |endpoints|. Remove them both from the list.
 
-			<li>If |s|'s endpoints are <a>discontiguous</a>, go back to step 4.
+			<li>If |s|'s endpoints are <a>discontiguous</a>, go back to <em>Empty Check</em>.
 
-			<li>If |S| is not empty:
+			<li>While |endpoints| is not empty:
 				<ol>
-					<li>Let |next| be the first segment in |S|.
+					<li>Create a [=gap decoration segment=] |next| from the first two items in |endpoints|, leaving them both in the list.
 					<li>Let |candidate| be <a>UNION</a>(|s|, |next|).
-					<li>If |candidate|'s endpoints are <a>discontiguous</a>, go to step 9.
-					<li>If |break| is ''column-rule-break/intersection'' and |candidate| is not <a>flanked by spanning items</a>, go to step 9.
-					<li>Remove the first segment from |S|.
+					<li>If |candidate|'s endpoints are <a>discontiguous</a>, exit this loop.
+					<li>If |break| is ''column-rule-break/intersection'' and |candidate| is not <a>flanked by spanning items</a>, exit this loop.
+					<li>Remove the first two items from |endpoints|.
 					<li>Set |s| to <a>UNION</a>(|s|, |next|).
-					<li>Go back to step 8.
 				</ol>
+			</li>
 
-			<li>[=Apply offsets to a segment|Apply offsets to=] |s|, then append it to |C|.
+			<li>[=Apply offsets to a segment|Apply offsets to=] |s|, then append it to |S|.
 
-			<li>Go back to step 4.
+			<li>Go back to <em>Empty Check</em>.
 		</ol>
 	</div>
 
@@ -576,7 +559,7 @@ Break behaviors at intersections: The 'column-rule-break', 'row-rule-break', and
 
 	Sets the behavior for breaking decorations within a given gap into segments
 	at visible "T" or "cross" intersections formed by items in the container.
-	Precise details for how to apply these values are given in the steps to [=determine painted segments=].
+	Precise details for how to apply these values are given in the steps to [=determine gap decoration segments=].
 
 	<dl dfn-type="value" dfn-for="column-rule-break, row-rule-break">
 		<dt><dfn>none</dfn>