affix.js in bootstrap-sass-3.1.1.1

- old
+ new

@@ -53,22 +53,20 @@
     var position     = this.$element.offset()
     var offset       = this.options.offset
     var offsetTop    = offset.top
     var offsetBottom = offset.bottom
 
-    if (this.affixed == 'top') position.top += scrollTop
-
     if (typeof offset != 'object')         offsetBottom = offsetTop = offset
     if (typeof offsetTop == 'function')    offsetTop    = offset.top(this.$element)
     if (typeof offsetBottom == 'function') offsetBottom = offset.bottom(this.$element)
 
     var affix = this.unpin   != null && (scrollTop + this.unpin <= position.top) ? false :
                 offsetBottom != null && (position.top + this.$element.height() >= scrollHeight - offsetBottom) ? 'bottom' :
                 offsetTop    != null && (scrollTop <= offsetTop) ? 'top' : false
 
     if (this.affixed === affix) return
-    if (this.unpin) this.$element.css('top', '')
+    if (this.unpin != null) this.$element.css('top', '')
 
     var affixType = 'affix' + (affix ? '-' + affix : '')
     var e         = $.Event(affixType + '.bs.affix')
 
     this.$element.trigger(e)
@@ -82,10 +80,10 @@
       .removeClass(Affix.RESET)
       .addClass(affixType)
       .trigger($.Event(affixType.replace('affix', 'affixed')))
 
     if (affix == 'bottom') {
-      this.$element.offset({ top: scrollHeight - offsetBottom - this.$element.height() })
+      this.$element.offset({ top: position.top })
     }
   }
 
 
   // AFFIX PLUGIN DEFINITION