[css-flexbox] Initial commit of a bunch of rephrasings of Resolving Flexible Lengths.

Author: fantasai

css-flexbox/Overview.bs

@@ -2322,8 +2322,9 @@ Resolving Flexible Lengths</h3>
 		<li>
 			<strong>Size inflexible items.</strong>
 			For any items that have a flex factor of zero,
-			set their used main size
-			to their <i>hypothetical main size</i>.
+			set their <i>target main size</i>
+			to their <i>hypothetical main size</i>
+			and freeze them.
 
 			If the <i>flex grow factor</i> is being used for this algorithm,
 			if any flexible items have a <a>flex base size</a> greater than their <a>hypothetical main size</a>,
@@ -2336,107 +2337,90 @@ Resolving Flexible Lengths</h3>
 			and freeze them.
 
 		<li>
-			<strong>Calculate free space.</strong>
-			Sum the sizes of all items on the line:
-			for frozen items,
-			use their outer main size;
-			for all other items,
-			both flexible and inflexible,
-			use their outer <a>flex base size</a>.
-			Subtract this sum from the flex container's inner main size.
-			This is the free space.
+			<strong>Calculate initial <dfn>free space</dfn>.</strong>
+			Sum the outer sizes of all items on the line,
+			and subtract this from the flex container's inner main size.
+			For frozen items, use their used main size;
+			for other items, use their <a>flex base size</a>.
+			This is the initial <i>free space</i>.
 
 		<li>
-			<strong>Calculate desired free space.</strong>
-			If the free space is zero or positive,
-			then for each <a>flex item</a> on the line,
-			its <var>originally desired free space</var>
-			is the free space multiplied by the flex grow factor.
-
-			Otherwise, if the free space is negative,
-			then first sum the flex shrink factors of all the flex items on the line.
-			If this number is greater than 1, set it to 1.
-			Let this result be the <var>scaled flex factor sum</var>.
-			For each flex item, multiply its flex shrink factor by its <a>flex base size</a>.
-			Then, renormalize each flex shrink factor so that their sum is the <var>scaled flex factor sum</var>.
-			Then, multiply the flex shrink factor by the free space,
-			and let the result be the <var>originally desired free space</var>.
+			<strong>Calculate each item‘s <dfn>desired free space</dfn>.</strong>
+			<li>
+				If the initial <i>free space</i> is zero or positive,
+				each <i>flex item</i>’s <i>desired free space</i> is
+				the initial <i>free space</i> multiplied by the item’s <i>flex grow factor</i>.
+			<li>
+				If the initial <i>free space</i> is negative,
+				then first sum the flex shrink factors of all the flex items on the line.
+				If this number is greater than 1, set it to 1.
+				Let this result be the <var>scaled flex factor sum</var>.
+				For each flex item, multiply its flex shrink factor by its <a>flex base size</a>.
+				Then, normalize each <i>flex shrink factor</i> so that their sum is the <var>scaled flex factor sum</var>.
+				Then, multiply the <i>flex shrink factor</i> by the initial <i>free space</i>,
+				and let the result be the <i>desired free space</var>.
+			</dl>
 
 		<li>
-			Loop:
-
-			<ol>
+			<strong>Distribute <i>free space</i>.</strong>
+			<ol type=a>
 				<li>
-					<strong>Check that you can distribute any space.</strong>
-					If all the non-frozen flex items on the line have a flex factor of zero,
-					exit the algorithm.
+					<strong>Check for flexible items.</strong>
+					If all the <i>flex items</i> on the line are frozen,
+					free space has been distributed;
+					exit this step.
 
 				<li>
-					<strong>Reset desired free space.</strong>
-					For each non-frozen flex item on the line,
-					set its <var>desired free space</var>
-					to its <var>originally desired free space</var>.
+					<strong>Calculate the remaining <i>free space</i></strong>
+					as for initial <i>free space</i>, above.
 
 				<li>
-					<strong>Recalculate free space.</strong>
-					Calculate the free space again,
-					according to the “Calculate free space” step before this loop.
-					<span class='note'>Note that this does not alter the desired free space of the items.</span>
+					<strong>Find each unfrozen item’s <dfn>normalized free space</dfn>.</strong>
+					If the remaining <i>free space</i> is non-zero,
+					and its magnitude is less than that of the sum of the non-frozen <i>flex items</i>’ <i>desired free space</i>,
+					multiply each item’s <i>desired free space</i>
+					by the ratio (<var>remaining free space</var>/<var>initial free space</var>).
+					This is the item’s <i>normalized free space</i>.
+					Otherwise, use each item’s <i>desired free space</i> as its <i>normalized free space</i>.
 
 				<li>
-					<strong>Normalize desired free space if necessary.</strong>
-					If the free space is positive,
-					and the sum of the <var>desired free spaces</var> of all the non-frozen flex items on the line
-					is greater than the free space,
-					normalize all the <var>desired free spaces</var> so that they sum exactly to the free space
-					while maintaining their magnitudes relative to each other.
-
-					Otherwise, if the free space is negative,
-					and the sum of the <var>desired free spaces</var> of all the non-frozen flex items on the line
-					is less than the free space,
-					normalize all the <var>desired free spaces</var> so that they sum exactly to the free space
-					while maintaining their magnitudes relative to each other.
-
-					Otherwise, if the free space is zero,
-					set the <var>desired free spaces</var> of all the non-frozen flex items on the line
-					to zero.
-
-				<li>
-					<strong>Adjust main size.</strong>
-					Set each non-frozen flex item's used main size
-					to the sum of its <a>flex base size</a> and its <var>desired free space</var>.
-
+					<strong>Calculate each item’s <dfn>target main size</dfn>.</strong>
+					Set each non-frozen flex item's <i>target main size</i>
+					to the sum of its <a>flex base size</a> and its <var>normalized free space</var>.
 					Note: This may result in a negative main size temporarily.
 
 				<li>
 					<strong>Fix min/max violations.</strong>
-					Clamp each non-frozen item's main size by its min and max main size properties.
+					Clamp each non-frozen item's <i>target main size</i> by its min and max main size properties.
 					If the item's main size was made smaller by this, it's a max violation.
 					If the item's main size was made larger by this, it's a min violation.
 
 				<li>
-					The total violation is the sum of the adjustments from the previous step
-					(<code><var>clamped size</var> - <var>unclamped size</var></code>).
+					<strong>Freeze over-flexed items.</strong>
+					The total violation is the sum of the adjustments from the previous step,
+					<code>&sum;(<var>clamped size</var> - <var>unclamped size</var></code>).
 					If the total violation is:
 
 					<dl>
 						<dt>Zero
 						<dd>
-							Exit the algorithm.
+							Do nothing.
 
 						<dt>Positive
 						<dd>
-							Freeze all the items with min violations,
-							reset all other items to their size upon entering this algorithm,
-							and return to the start of this loop.
+							Freeze all the items with min violations to their clamped size.
 
 						<dt>Negative
 						<dd>
-							Freeze all the items with max violations,
-							reset all other items to their size upon entering this algorithm,
-							and return to the start of this loop.
+							Freeze all the items with max violations to their clamped size.
 					</dl>
+				<li>
+					<strong>Loop:</strong>
+					Return to the first step, “Distribute free space.”
 			</ol>
+			<li>
+				<strong>Set each fozen item’s used size to its <i>target main size</i>.</strong>
+				Note: All items should be frozen at this point.
 	</ol>
 
 <h3 id='intrinsic-sizes'>