示例#1
0
 function get_pages_traverse_block(&$box, &$next, &$previous, $penalty)
 {
     $locations = array();
     // Absolute/fixed positioned blocks do not cause page breaks
     // (CSS 2.1. 13.2.3 Content outside the page box)
     $position = $box->get_css_property(CSS_POSITION);
     if ($position == POSITION_FIXED || $position == POSITION_ABSOLUTE) {
         return $locations;
     }
     // Fake cell boxes do not generate page break locations
     if (is_a($box, 'FakeTableCellBox')) {
         return $locations;
     }
     /**
      * Check for breaks in block box vertical margin
      */
     /**
      * Check for pre-breaks
      */
     if (PageBreakLocator::has_forced_page_break_before($box)) {
         $location = new PageBreakLocation($box->get_top_margin(), FORCED_PAGE_BREAK_BONUS);
     } elseif (!is_null($previous) && $previous->get_css_property(CSS_PAGE_BREAK_AFTER) == PAGE_BREAK_AVOID) {
         $location = new PageBreakLocation($box->get_top_margin(), $penalty + PAGE_BREAK_AFTER_AVOID_PENALTY);
     } elseif ($box->get_css_property(CSS_PAGE_BREAK_BEFORE) == PAGE_BREAK_AVOID) {
         $location = new PageBreakLocation($box->get_top_margin(), $penalty + PAGE_BREAK_BEFORE_AVOID_PENALTY);
     } else {
         $location = new PageBreakLocation($box->get_top_margin(), $penalty);
     }
     $locations[] = $location;
     /**
      * Check for post-breaks
      */
     if (PageBreakLocator::has_forced_page_break_after($box)) {
         $location = new PageBreakLocation($box->get_bottom_margin(), FORCED_PAGE_BREAK_BONUS);
     } elseif (!is_null($next) && $next->get_css_property(CSS_PAGE_BREAK_BEFORE) == PAGE_BREAK_AVOID) {
         $location = new PageBreakLocation($box->get_bottom_margin(), $penalty + PAGE_BREAK_AFTER_AVOID_PENALTY);
     } elseif ($box->get_css_property(CSS_PAGE_BREAK_AFTER) == PAGE_BREAK_AVOID) {
         $location = new PageBreakLocation($box->get_bottom_margin(), $penalty + PAGE_BREAK_AFTER_AVOID_PENALTY);
     } else {
         $location = new PageBreakLocation($box->get_bottom_margin(), $penalty);
     }
     $locations[] = $location;
     /**
      * Check for breaks inside this box
      * Note that this check should be done after page-break-before/after checks,
      * as 'penalty' value may be modified here
      */
     if ($box->get_css_property(CSS_PAGE_BREAK_INSIDE) == PAGE_BREAK_AVOID) {
         $penalty += PAGE_BREAK_INSIDE_AVOID_PENALTY;
     }
     /**
      * According to CSS 2.1, 13.3.5 'Best' page breaks, 
      * User agent shoud /Avoid breaking inside a block that has a border/
      *
      * From my point of view, top and bottom borders should not affect page 
      * breaks (as they're not broken by page break), while left and right ones - should.
      */
     $border_left =& $box->get_css_property(CSS_BORDER_LEFT);
     $border_right =& $box->get_css_property(CSS_BORDER_RIGHT);
     $has_left_border = $border_left->style != BS_NONE && $border_left->width->getPoints() > 0;
     $has_right_border = $border_left->style != BS_NONE && $border_left->width->getPoints() > 0;
     if ($has_left_border || $has_right_border) {
         $penalty += PAGE_BREAK_BORDER_PENALTY;
     }
     /**
      * Process box content
      */
     $locations = array_merge($locations, PageBreakLocator::get_pages_traverse($box, $penalty));
     return $locations;
 }