* @version dompdf_trunk_with_helmut_mods.20090528
* - fix text decoration positions according to font metrics
* @version 20090610
* - better accuracy on using different renderer as cpdf, added comments
*/
/* $Id: text_renderer.cls.php 186 2009-10-19 22:42:06Z eclecticgeek@gmail.com $ */
/**
* Renders text frames
*
* @access private
* @package dompdf
*/
class Text_Renderer extends Abstract_Renderer {
const DECO_THICKNESS = 0.04; // Thickness of underline. Screen: 0.08, print: better less, e.g. 0.04
//Tweaking if $base and $descent are not accurate.
//Check method_exists( $this->_canvas, "get_cpdf" )
//- For cpdf these can and must stay 0, because font metrics are used directly.
//- For other renderers, if different values are wanted, separate the parameter sets.
// But $size and $size-$height seem to be accurate enough
const UNDERLINE_OFFSET = 0.0; // Relative to bottom of text, as fraction of height.
const OVERLINE_OFFSET = 0.0; // Relative to top of text
const LINETHROUGH_OFFSET = 0.0; // Relative to centre of text.
const DECO_EXTENSION = 0.0; // How far to extend lines past either end, in pt
//........................................................................
function render(Frame $frame) {
$style = $frame->get_style();
list($x, $y) = $frame->get_position();
$cb = $frame->get_containing_block();
if ( ($ml = $style->margin_left) == "auto" || $ml == "none" )
$ml = 0;
if ( ($pl = $style->padding_left) == "auto" || $pl == "none" )
$pl = 0;
if ( ($bl = $style->border_left_width) == "auto" || $bl == "none" )
$bl = 0;
$x += $style->length_in_pt( array($ml, $pl, $bl), $cb["w"] );
$text = $frame->get_text();
$font = $style->font_family;
$size = $style->font_size;
$height = $style->height;
$spacing = $frame->get_text_spacing() + $style->word_spacing;
// if ( preg_replace("/[\s]+/", "", $text) == "" )
// return;
$this->_canvas->text($x, $y, $text,
$font, $size,
$style->color, $spacing);
if ( method_exists( $this->_canvas, "get_cpdf" ) ) {
$base = ($this->_canvas->get_cpdf()->fonts[$this->_canvas->get_cpdf()->currentFont]['FontBBox'][3]*$size)/1000;
$descent = ($this->_canvas->get_cpdf()->fonts[$this->_canvas->get_cpdf()->currentFont]['FontBBox'][1]*$size)/1000;
//print 'Text_Renderer cpdf:'.$base.' '.$descent.' '.$size.'
';
} else {
//Descent is font part below baseline, typically negative. $height is about full height of font box.
//$descent = -$size/6; is less accurate, depends on font family.
$base = $size;
$descent = $size-$height;
//print 'Text_Renderer other than cpdf:'.$base.' '.$descent.' '.$size.'
';
}
// Handle text decoration:
// http://www.w3.org/TR/CSS21/text.html#propdef-text-decoration
// Draw all applicable text-decorations. Start with the root and work
// our way down.
$p = $frame;
$stack = array();
while ( $p = $p->get_parent() )
$stack[] = $p;
while ( count($stack) > 0 ) {
$f = array_pop($stack);
$deco_y = $y;
if ( ($text_deco = $f->get_style()->text_decoration) === "none" )
continue;
$color = $f->get_style()->color;
switch ($text_deco) {
default:
continue;
case "underline":
$deco_y += $base - $descent+ $size * (self::UNDERLINE_OFFSET - self::DECO_THICKNESS/2);
break;
case "overline":
$deco_y += $size * (self::OVERLINE_OFFSET + self::DECO_THICKNESS/2);
break;
case "line-through":
$deco_y += $base * 0.7 + $size * self::LINETHROUGH_OFFSET;
break;
}
$dx = 0;
$x1 = $x - self::DECO_EXTENSION;
$x2 = $x + $style->width + $dx + self::DECO_EXTENSION;
$this->_canvas->line($x1, $deco_y, $x2, $deco_y, $color, $size * self::DECO_THICKNESS);
}
}
}
?>