added alternate pseudo-algorithm

Author: howcom

css3-multicol/Overview.src.html

@@ -779,7 +779,7 @@ <h3>Pseudo-algorithm</h3>
 (04)  fi
 (05)  
 (06)  if (available-width = unknown) and (column-count != auto) and (column-width != auto) then
-(07)    N := column-count;
+(07)    N := column-count;  
 (08)    W := column-width;
 (09)    exit;
 (10)  fi
@@ -808,6 +808,48 @@ <h3>Pseudo-algorithm</h3>
 (41)  fi
 </pre>
 
+<p><span class=issue>Alternative pseudo-algorithm:
+
+<pre>
+
+(01)  if ((column-width = auto) and (column-count = auto)) or
+(02)     ((available-width = unknown) and (column-count = auto)) then
+(03)    exit; /* no columns */
+(04)  fi
+(05)  
+(06)  if (available-width = unknown) and (column-count != auto) and (column-width != auto) then
+(07)    N := column-count;  
+(08)    W := column-width;
+(09)    exit;
+(10)  fi
+
+(12)  if (available-width = unknown) then
+(13)    available-width := shrink-to-fit;
+(14)  fi
+
+/* the next block is used when column-count is set, and column-width is auto  */
+
+(16)  if (column-width = auto) then
+(18)    N := column-count;
+(19)    W := max(0, (available-width - ((N - 1) * column-gap))/N);
+        exit;
+      fi
+
+/* the next block is used when column-width is set, and column-count is auto */
+   
+(27)  if (column-count = auto) then
+(32)    N := min(1, floor((available-width + column-gap) / (column-width + column-gap)));
+(33)    W := ((available-width + column-gap) / N) - column-gap;
+        exit;
+      fi 
+
+/* the next block is used if both column-count and column-width are set */
+
+(39)  N := min(column-count, floor((available-width + column-gap) / (column-width + column-gap)))
+(40)  W := ((available-width + column-gap) / N) - column-gap;
+
+</pre>
+
 
 <p>In paged media, user agents may perform this calculation on a
 per-page basis.