absolute_positioned[] =& $box; } function add_fixed_positioned(&$box) { $this->fixed_positioned[] =& $box; } function add_float(&$float) { $this->_floats[0][] =& $float; } function container_uid() { return $this->container_uid[0]; } function ¤t_floats() { return $this->_floats[0]; } // Get the bottom edge coordinate of the bottommost float in // current formatting context // // @return null in case of no floats exists in current context // numeric coordinate value otherwise // function float_bottom() { $floats =& $this->current_floats(); if (count($floats) == 0) { return null; } $bottom = $floats[0]->get_bottom_margin(); $size = count($floats); for ($i=1; $i<$size; $i++) { $bottom = min($bottom, $floats[$i]->get_bottom_margin()); }; return $bottom; } // Calculates the leftmost x-coordinate not covered by floats in current context // at the given level (y-coordinate) // // @param $x starting X coordinate (no point to the left of this allowed) // @param $y Y coordinate we're searching at // @return the leftmost X coordinate value // function float_left_x($x, $y) { $floats =& $this->current_floats(); $size = count($floats); for ($i=0; $i<$size; $i++) { $float =& $floats[$i]; // Process only left-floating boxes if ($float->get_css_property(CSS_FLOAT) == FLOAT_LEFT) { // Check if this float contains given Y-coordinate // // Note that top margin coordinate is inclusive but // bottom margin coordinate is exclusive! The cause is following: // - if we have several floats in one line, their top margin edge Y coordinates will be equal, // so we must use agreater or equal sign to avod placing all floats at one X coordinate // - on the other side, if we place one float under the other, the top margin Y coordinate // of bottom float will be equal to bottom margin Y coordinate of the top float and // we should NOT offset tho bottom float in this case // if ($float->get_top_margin() + EPSILON >= $y && $float->get_bottom_margin() < $y) { $x = max($x, $float->get_right_margin()); }; }; }; return $x; } // Calculates position of left floating box (taking into account the possibility // of "wrapping" float to next line in case we have not enough space at current level (Y coordinate) // // @param $parent reference to a parent box // @param $width width of float being placed. Full width! so, extra horizontal space (padding, margins and borders) is added here too // @param $x [out] X coordinate of float upper-left corner // @param $y [in,out] Y coordinate of float upper-left corner // function float_left_xy(&$parent, $width, &$x, &$y) { // Numbler of floats to clear; we need this because of the following example: //
//
T
//
T
//
T
// in this case the third float will be rendered directly under the second, so only the // second float should be cleared $clear = 0; $floats =& $this->current_floats(); // Prepare information about the float bottom coordinates $float_bottoms = array(); $size = count($floats); for ($i=0; $i<$size; $i++) { $float_bottoms[] = $floats[$i]->get_bottom_margin(); }; // Note that the sort function SHOULD NOT maintain key-value assotiations! rsort($float_bottoms); do { $x = $this->float_left_x($parent->get_left(), $y); // Check if current float will fit into the parent box // OR if there's no parent boxes with constrained width (it will expanded in this case anyway) // small value to hide the rounding errors $parent_wc = $parent->get_css_property(CSS_WIDTH); if ($parent->get_right() + EPSILON >= $x + $width || $parent->mayBeExpanded()) { // Will fit; // Check if current float will intersect the existing left-floating box // $x1 = $this->float_right_x($parent->get_right(), $y); if ($x1 + EPSILON > $x + $width) { return; }; return; }; // print("CLEAR
"); // No, float does not fit at current level, let's try to 'clear' some previous floats $clear++; // Check if we've cleared all existing floats; the loop will be terminated in this case, of course, // but we can get a notice/warning message if we'll try to access the non-existing array element if ($clear <= count($floats)) { $y = min( $y, $float_bottoms[$clear-1] ); }; } while ($clear <= count($floats)); // We need to check if all floats have been cleared to avoid infinite loop // All floats are cleared; fall back to the leftmost X coordinate $x = $parent->get_left(); } // Get the right edge coordinate of the rightmost float in // current formatting context // // @return null in case of no floats exists in current context // numeric coordinate value otherwise // function float_right() { $floats =& $this->current_floats(); if (count($floats) == 0) { return null; } $right = $floats[0]->get_right_margin(); $size = count($floats); for ($i=1; $i<$size; $i++) { $right = max($right, $floats[$i]->get_right_margin()); }; return $right; } // Calculates the rightmost x-coordinate not covered by floats in current context // at the given level (y-coordinate) // // @param $x starting X coordinate (no point to the right of this allowed) // @param $y Y coordinate we're searching at // @return the rightmost X coordinate value // function float_right_x($x, $y) { $floats =& $this->current_floats(); $size = count($floats); for ($i=0; $i<$size; $i++) { $float =& $floats[$i]; // Process only right-floating boxes if ($float->get_css_property(CSS_FLOAT) == FLOAT_RIGHT) { // Check if this float contains given Y-coordinate // // Note that top margin coordinate is inclusive but // bottom margin coordinate is exclusive! The cause is following: // - if we have several floats in one line, their top margin edge Y coordinates will be equal, // so we must use agreater or equal sign to avod placing all floats at one X coordinate // - on the other side, if we place one float under the other, the top margin Y coordinate // of bottom float will be equal to bottom margin Y coordinate of the top float and // we should NOT offset tho bottom float in this case // if ($float->get_top_margin() + EPSILON >= $y && $float->get_bottom_margin() < $y) { $x = min($x, $float->get_left_margin()); }; }; }; return $x; } // Calculates position of right floating box (taking into account the possibility // of "wrapping" float to next line in case we have not enough space at current level (Y coordinate) // // @param $parent reference to a parent box // @param $width width of float being placed. Full width! so, extra horizontal space (padding, margins and borders) is added here too // @param $x [out] X coordinate of float upper-right corner // @param $y [in,out] Y coordinate of float upper-right corner // function float_right_xy(&$parent, $width, &$x, &$y) { // Numbler of floats to clear; we need this because of the following example: //
//
T
//
T
//
T
// in this case the third float will be rendered directly under the second, so only the // second float should be cleared $clear = 0; $floats =& $this->current_floats(); // Prepare information about the float bottom coordinates $float_bottoms = array(); $size = count($floats); for ($i=0; $i<$size; $i++) { $float_bottoms[] = $floats[$i]->get_bottom_margin(); }; // Note that the sort function SHOULD NOT maintain key-value assotiations! rsort($float_bottoms); do { $x = $this->float_right_x($parent->get_right(), $y); // Check if current float will fit into the parent box // OR if the parent box have width: auto (it will expanded in this case anyway) // if ($parent->get_right() + EPSILON > $x || $parent->width == WIDTH_AUTO) { // Will fit; // Check if current float will intersect the existing left-floating box // $x1 = $this->float_left_x($parent->get_left(), $y); if ($x1 - EPSILON < $x - $width) { return; }; }; // No, float does not fit at current level, let's try to 'clear' some previous floats $clear++; // Check if we've cleared all existing floats; the loop will be terminated in this case, of course, // but we can get a notice/warning message if we'll try to access the non-existing array element if ($clear <= count($floats)) { $y = min( $y, $float_bottoms[$clear-1] ); }; } while($clear <= count($floats)); // We need to check if all floats have been cleared to avoid infinite loop // All floats are cleared; fall back to the rightmost X coordinate $x = $parent->get_right(); } function FlowContext() { $this->absolute_positioned = array(); $this->fixed_positioned = array(); $this->viewport = array(); $this->_floats = array(array()); $this->collapsed_margins = array(0); $this->container_uid = array(1); } function get_collapsed_margin() { return $this->collapsed_margins[0]; } function &get_viewport() { return $this->viewport[0]; } function pop() { $this->pop_collapsed_margin(); $this->pop_floats(); } function pop_collapsed_margin() { array_shift($this->collapsed_margins); } function pop_container_uid() { array_shift($this->container_uid); } function pop_floats() { array_shift($this->_floats); } function push() { $this->push_collapsed_margin(0); $this->push_floats(); } function push_collapsed_margin($margin) { array_unshift($this->collapsed_margins, $margin); } function push_container_uid($uid) { array_unshift($this->container_uid, $uid); } function push_floats() { array_unshift($this->_floats, array()); } function push_viewport(&$box) { array_unshift($this->viewport, $box); } function &point_in_floats($x, $y) { // Scan the floating children list of the current container box $floats =& $this->current_floats(); $size = count($floats); for ($i=0; $i<$size; $i++) { if ($floats[$i]->contains_point_margin($x, $y)) { return $floats[$i]; } } $dummy = null; return $dummy; } function pop_viewport() { array_shift($this->viewport); } function sort_absolute_positioned_by_z_index() { usort($this->absolute_positioned, "cmp_boxes_by_z_index"); } } function cmp_boxes_by_z_index($a, $b) { $a_z = $a->get_css_property(CSS_Z_INDEX); $b_z = $b->get_css_property(CSS_Z_INDEX); if ($a_z == $b_z) return 0; return ($a_z < $b_z) ? -1 : 1; } ?>