vendor/dompdf/dompdf/src/Renderer/AbstractRenderer.php

   1 <?php
   2 /**
   3  * @package dompdf
   4  * @link    http://dompdf.github.com/
   5  * @author  Benj Carson <benjcarson@digitaljunkies.ca>
   6  * @author  Helmut Tischer <htischer@weihenstephan.org>
   7  * @author  Fabien Ménager <fabien.menager@gmail.com>
   8  * @license http://www.gnu.org/copyleft/lesser.html GNU Lesser General Public License
   9  */
  10 namespace Dompdf\Renderer;
  11
  12 use Dompdf\Adapter\CPDF;
  13 use Dompdf\Css\Color;
  14 use Dompdf\Css\Style;
  15 use Dompdf\Dompdf;
  16 use Dompdf\Helpers;
  17 use Dompdf\Frame;
  18 use Dompdf\Image\Cache;
  19
  20 /**
  21  * Base renderer class
  22  *
  23  * @package dompdf
  24  */
  25 abstract class AbstractRenderer
  26 {
  27
  28     /**
  29      * Rendering backend
  30      *
  31      * @var \Dompdf\Canvas
  32      */
  33     protected $_canvas;
  34
  35     /**
  36      * Current dompdf instance
  37      *
  38      * @var Dompdf
  39      */
  40     protected $_dompdf;
  41
  42     /**
  43      * Class constructor
  44      *
  45      * @param Dompdf $dompdf The current dompdf instance
  46      */
  47     function __construct(Dompdf $dompdf)
  48     {
  49         $this->_dompdf = $dompdf;
  50         $this->_canvas = $dompdf->get_canvas();
  51     }
  52
  53     /**
  54      * Render a frame.
  55      *
  56      * Specialized in child classes
  57      *
  58      * @param Frame $frame The frame to render
  59      */
  60     abstract function render(Frame $frame);
  61
  62     //........................................................................
  63
  64     /**
  65      * Render a background image over a rectangular area
  66      *
  67      * @param string $url   The background image to load
  68      * @param float $x      The left edge of the rectangular area
  69      * @param float $y      The top edge of the rectangular area
  70      * @param float $width  The width of the rectangular area
  71      * @param float $height The height of the rectangular area
  72      * @param Style $style  The associated Style object
  73      *
  74      * @throws \Exception
  75      */
  76     protected function _background_image($url, $x, $y, $width, $height, $style)
  77     {
  78         if (!function_exists("imagecreatetruecolor")) {
  79             throw new \Exception("The PHP GD extension is required, but is not installed.");
  80         }
  81
  82         $sheet = $style->get_stylesheet();
  83
  84         // Skip degenerate cases
  85         if ($width == 0 || $height == 0) {
  86             return;
  87         }
  88
  89         $box_width = $width;
  90         $box_height = $height;
  91
  92         //debugpng
  93         if ($this->_dompdf->get_option("debugPng")) print '[_background_image ' . $url . ']';
  94
  95         list($img, $type, /*$msg*/) = Cache::resolve_url(
  96             $url,
  97             $sheet->get_protocol(),
  98             $sheet->get_host(),
  99             $sheet->get_base_path(),
 100             $this->_dompdf
 101         );
 102
 103         // Bail if the image is no good
 104         if (Cache::is_broken($img)) {
 105             return;
 106         }
 107
 108         //Try to optimize away reading and composing of same background multiple times
 109         //Postponing read with imagecreatefrom   ...()
 110         //final composition parameters and name not known yet
 111         //Therefore read dimension directly from file, instead of creating gd object first.
 112         //$img_w = imagesx($src); $img_h = imagesy($src);
 113
 114         list($img_w, $img_h) = Helpers::dompdf_getimagesize($img, $this->_dompdf->getHttpContext());
 115         if (!isset($img_w) || $img_w == 0 || !isset($img_h) || $img_h == 0) {
 116             return;
 117         }
 118
 119         $repeat = $style->background_repeat;
 120         $dpi = $this->_dompdf->get_option("dpi");
 121
 122         //Increase background resolution and dependent box size according to image resolution to be placed in
 123         //Then image can be copied in without resize
 124         $bg_width = round((float)($width * $dpi) / 72);
 125         $bg_height = round((float)($height * $dpi) / 72);
 126
 127         //Need %bg_x, $bg_y as background pos, where img starts, converted to pixel
 128
 129         list($bg_x, $bg_y) = $style->background_position;
 130
 131         if (Helpers::is_percent($bg_x)) {
 132             // The point $bg_x % from the left edge of the image is placed
 133             // $bg_x % from the left edge of the background rectangle
 134             $p = ((float)$bg_x) / 100.0;
 135             $x1 = $p * $img_w;
 136             $x2 = $p * $bg_width;
 137
 138             $bg_x = $x2 - $x1;
 139         } else {
 140             $bg_x = (float)($style->length_in_pt($bg_x) * $dpi) / 72;
 141         }
 142
 143         $bg_x = round($bg_x + $style->length_in_pt($style->border_left_width) * $dpi / 72);
 144
 145         if (Helpers::is_percent($bg_y)) {
 146             // The point $bg_y % from the left edge of the image is placed
 147             // $bg_y % from the left edge of the background rectangle
 148             $p = ((float)$bg_y) / 100.0;
 149             $y1 = $p * $img_h;
 150             $y2 = $p * $bg_height;
 151
 152             $bg_y = $y2 - $y1;
 153         } else {
 154             $bg_y = (float)($style->length_in_pt($bg_y) * $dpi) / 72;
 155         }
 156
 157         $bg_y = round($bg_y + $style->length_in_pt($style->border_top_width) * $dpi / 72);
 158
 159         //clip background to the image area on partial repeat. Nothing to do if img off area
 160         //On repeat, normalize start position to the tile at immediate left/top or 0/0 of area
 161         //On no repeat with positive offset: move size/start to have offset==0
 162         //Handle x/y Dimensions separately
 163
 164         if ($repeat !== "repeat" && $repeat !== "repeat-x") {
 165             //No repeat x
 166             if ($bg_x < 0) {
 167                 $bg_width = $img_w + $bg_x;
 168             } else {
 169                 $x += ($bg_x * 72) / $dpi;
 170                 $bg_width = $bg_width - $bg_x;
 171                 if ($bg_width > $img_w) {
 172                     $bg_width = $img_w;
 173                 }
 174                 $bg_x = 0;
 175             }
 176
 177             if ($bg_width <= 0) {
 178                 return;
 179             }
 180
 181             $width = (float)($bg_width * 72) / $dpi;
 182         } else {
 183             //repeat x
 184             if ($bg_x < 0) {
 185                 $bg_x = -((-$bg_x) % $img_w);
 186             } else {
 187                 $bg_x = $bg_x % $img_w;
 188                 if ($bg_x > 0) {
 189                     $bg_x -= $img_w;
 190                 }
 191             }
 192         }
 193
 194         if ($repeat !== "repeat" && $repeat !== "repeat-y") {
 195             //no repeat y
 196             if ($bg_y < 0) {
 197                 $bg_height = $img_h + $bg_y;
 198             } else {
 199                 $y += ($bg_y * 72) / $dpi;
 200                 $bg_height = $bg_height - $bg_y;
 201                 if ($bg_height > $img_h) {
 202                     $bg_height = $img_h;
 203                 }
 204                 $bg_y = 0;
 205             }
 206             if ($bg_height <= 0) {
 207                 return;
 208             }
 209             $height = (float)($bg_height * 72) / $dpi;
 210         } else {
 211             //repeat y
 212             if ($bg_y < 0) {
 213                 $bg_y = -((-$bg_y) % $img_h);
 214             } else {
 215                 $bg_y = $bg_y % $img_h;
 216                 if ($bg_y > 0) {
 217                     $bg_y -= $img_h;
 218                 }
 219             }
 220         }
 221
 222         //Optimization, if repeat has no effect
 223         if ($repeat === "repeat" && $bg_y <= 0 && $img_h + $bg_y >= $bg_height) {
 224             $repeat = "repeat-x";
 225         }
 226
 227         if ($repeat === "repeat" && $bg_x <= 0 && $img_w + $bg_x >= $bg_width) {
 228             $repeat = "repeat-y";
 229         }
 230
 231         if (($repeat === "repeat-x" && $bg_x <= 0 && $img_w + $bg_x >= $bg_width) ||
 232             ($repeat === "repeat-y" && $bg_y <= 0 && $img_h + $bg_y >= $bg_height)
 233         ) {
 234             $repeat = "no-repeat";
 235         }
 236
 237         //Use filename as indicator only
 238         //different names for different variants to have different copies in the pdf
 239         //This is not dependent of background color of box! .'_'.(is_array($bg_color) ? $bg_color["hex"] : $bg_color)
 240         //Note: Here, bg_* are the start values, not end values after going through the tile loops!
 241
 242         $filedummy = $img;
 243
 244         $is_png = false;
 245         $filedummy .= '_' . $bg_width . '_' . $bg_height . '_' . $bg_x . '_' . $bg_y . '_' . $repeat;
 246
 247         //Optimization to avoid multiple times rendering the same image.
 248         //If check functions are existing and identical image already cached,
 249         //then skip creation of duplicate, because it is not needed by addImagePng
 250         if ($this->_canvas instanceof CPDF &&
 251             $this->_canvas->get_cpdf()->image_iscached($filedummy)
 252         ) {
 253             $bg = null;
 254         } else {
 255
 256             // Create a new image to fit over the background rectangle
 257             $bg = imagecreatetruecolor($bg_width, $bg_height);
 258
 259             switch (strtolower($type)) {
 260                 case "png":
 261                     $is_png = true;
 262                     imagesavealpha($bg, true);
 263                     imagealphablending($bg, false);
 264                     $src = imagecreatefrompng($img);
 265                     break;
 266
 267                 case "jpeg":
 268                     $src = imagecreatefromjpeg($img);
 269                     break;
 270
 271                 case "gif":
 272                     $src = imagecreatefromgif($img);
 273                     break;
 274
 275                 case "bmp":
 276                     $src = Helpers::imagecreatefrombmp($img);
 277                     break;
 278
 279                 default:
 280                     return; // Unsupported image type
 281             }
 282
 283             if ($src == null) {
 284                 return;
 285             }
 286
 287             //Background color if box is not relevant here
 288             //Non transparent image: box clipped to real size. Background non relevant.
 289             //Transparent image: The image controls the transparency and lets shine through whatever background.
 290             //However on transparent image preset the composed image with the transparency color,
 291             //to keep the transparency when copying over the non transparent parts of the tiles.
 292             $ti = imagecolortransparent($src);
 293
 294             if ($ti >= 0) {
 295                 $tc = imagecolorsforindex($src, $ti);
 296                 $ti = imagecolorallocate($bg, $tc['red'], $tc['green'], $tc['blue']);
 297                 imagefill($bg, 0, 0, $ti);
 298                 imagecolortransparent($bg, $ti);
 299             }
 300
 301             //This has only an effect for the non repeatable dimension.
 302             //compute start of src and dest coordinates of the single copy
 303             if ($bg_x < 0) {
 304                 $dst_x = 0;
 305                 $src_x = -$bg_x;
 306             } else {
 307                 $src_x = 0;
 308                 $dst_x = $bg_x;
 309             }
 310
 311             if ($bg_y < 0) {
 312                 $dst_y = 0;
 313                 $src_y = -$bg_y;
 314             } else {
 315                 $src_y = 0;
 316                 $dst_y = $bg_y;
 317             }
 318
 319             //For historical reasons exchange meanings of variables:
 320             //start_* will be the start values, while bg_* will be the temporary start values in the loops
 321             $start_x = $bg_x;
 322             $start_y = $bg_y;
 323
 324             // Copy regions from the source image to the background
 325             if ($repeat === "no-repeat") {
 326
 327                 // Simply place the image on the background
 328                 imagecopy($bg, $src, $dst_x, $dst_y, $src_x, $src_y, $img_w, $img_h);
 329
 330             } else if ($repeat === "repeat-x") {
 331
 332                 for ($bg_x = $start_x; $bg_x < $bg_width; $bg_x += $img_w) {
 333                     if ($bg_x < 0) {
 334                         $dst_x = 0;
 335                         $src_x = -$bg_x;
 336                         $w = $img_w + $bg_x;
 337                     } else {
 338                         $dst_x = $bg_x;
 339                         $src_x = 0;
 340                         $w = $img_w;
 341                     }
 342                     imagecopy($bg, $src, $dst_x, $dst_y, $src_x, $src_y, $w, $img_h);
 343                 }
 344
 345             } else if ($repeat === "repeat-y") {
 346
 347                 for ($bg_y = $start_y; $bg_y < $bg_height; $bg_y += $img_h) {
 348                     if ($bg_y < 0) {
 349                         $dst_y = 0;
 350                         $src_y = -$bg_y;
 351                         $h = $img_h + $bg_y;
 352                     } else {
 353                         $dst_y = $bg_y;
 354                         $src_y = 0;
 355                         $h = $img_h;
 356                     }
 357                     imagecopy($bg, $src, $dst_x, $dst_y, $src_x, $src_y, $img_w, $h);
 358
 359                 }
 360
 361             } else if ($repeat === "repeat") {
 362
 363                 for ($bg_y = $start_y; $bg_y < $bg_height; $bg_y += $img_h) {
 364                     for ($bg_x = $start_x; $bg_x < $bg_width; $bg_x += $img_w) {
 365
 366                         if ($bg_x < 0) {
 367                             $dst_x = 0;
 368                             $src_x = -$bg_x;
 369                             $w = $img_w + $bg_x;
 370                         } else {
 371                             $dst_x = $bg_x;
 372                             $src_x = 0;
 373                             $w = $img_w;
 374                         }
 375
 376                         if ($bg_y < 0) {
 377                             $dst_y = 0;
 378                             $src_y = -$bg_y;
 379                             $h = $img_h + $bg_y;
 380                         } else {
 381                             $dst_y = $bg_y;
 382                             $src_y = 0;
 383                             $h = $img_h;
 384                         }
 385                         imagecopy($bg, $src, $dst_x, $dst_y, $src_x, $src_y, $w, $h);
 386                     }
 387                 }
 388             } else {
 389                 print 'Unknown repeat!';
 390             }
 391
 392             imagedestroy($src);
 393
 394         } /* End optimize away creation of duplicates */
 395
 396         $this->_canvas->clipping_rectangle($x, $y, $box_width, $box_height);
 397
 398         //img: image url string
 399         //img_w, img_h: original image size in px
 400         //width, height: box size in pt
 401         //bg_width, bg_height: box size in px
 402         //x, y: left/top edge of box on page in pt
 403         //start_x, start_y: placement of image relative to pattern
 404         //$repeat: repeat mode
 405         //$bg: GD object of result image
 406         //$src: GD object of original image
 407         //When using cpdf and optimization to direct png creation from gd object is available,
 408         //don't create temp file, but place gd object directly into the pdf
 409         if (!$is_png && $this->_canvas instanceof CPDF) {
 410             // Note: CPDF_Adapter image converts y position
 411             $this->_canvas->get_cpdf()->addImagePng($filedummy, $x, $this->_canvas->get_height() - $y - $height, $width, $height, $bg);
 412         } else {
 413             $tmp_dir = $this->_dompdf->get_option("temp_dir");
 414             $tmp_name = tempnam($tmp_dir, "bg_dompdf_img_");
 415             @unlink($tmp_name);
 416             $tmp_file = "$tmp_name.png";
 417
 418             //debugpng
 419             if ($this->_dompdf->get_option("debugPng")) print '[_background_image ' . $tmp_file . ']';
 420
 421             imagepng($bg, $tmp_file);
 422             $this->_canvas->image($tmp_file, $x, $y, $width, $height);
 423             imagedestroy($bg);
 424
 425             //debugpng
 426             if ($this->_dompdf->get_option("debugPng")) print '[_background_image unlink ' . $tmp_file . ']';
 427
 428             if (!$this->_dompdf->get_option("debugKeepTemp")) {
 429                 unlink($tmp_file);
 430             }
 431         }
 432
 433         $this->_canvas->clipping_end();
 434     }
 435
 436     protected function _get_dash_pattern($style, $width)
 437     {
 438         $pattern = array();
 439
 440         switch ($style) {
 441             default:
 442                 /*case "solid":
 443                 case "double":
 444                 case "groove":
 445                 case "inset":
 446                 case "outset":
 447                 case "ridge":*/
 448             case "none":
 449                 break;
 450
 451             case "dotted":
 452                 if ($width <= 1)
 453                     $pattern = array($width, $width * 2);
 454                 else
 455                     $pattern = array($width);
 456                 break;
 457
 458             case "dashed":
 459                 $pattern = array(3 * $width);
 460                 break;
 461         }
 462
 463         return $pattern;
 464     }
 465
 466     protected function _border_none($x, $y, $length, $color, $widths, $side, $corner_style = "bevel", $r1 = 0, $r2 = 0)
 467     {
 468         return;
 469     }
 470
 471     protected function _border_hidden($x, $y, $length, $color, $widths, $side, $corner_style = "bevel", $r1 = 0, $r2 = 0)
 472     {
 473         return;
 474     }
 475
 476     // Border rendering functions
 477
 478     protected function _border_dotted($x, $y, $length, $color, $widths, $side, $corner_style = "bevel", $r1 = 0, $r2 = 0)
 479     {
 480         $this->_border_line($x, $y, $length, $color, $widths, $side, $corner_style, "dotted", $r1, $r2);
 481     }
 482
 483
 484     protected function _border_dashed($x, $y, $length, $color, $widths, $side, $corner_style = "bevel", $r1 = 0, $r2 = 0)
 485     {
 486         $this->_border_line($x, $y, $length, $color, $widths, $side, $corner_style, "dashed", $r1, $r2);
 487     }
 488
 489
 490     protected function _border_solid($x, $y, $length, $color, $widths, $side, $corner_style = "bevel", $r1 = 0, $r2 = 0)
 491     {
 492         // TODO: Solve rendering where one corner is beveled (radius == 0), one corner isn't.
 493         if ($corner_style !== "bevel" || $r1 > 0 || $r2 > 0) {
 494             // do it the simple way
 495             $this->_border_line($x, $y, $length, $color, $widths, $side, $corner_style, "solid", $r1, $r2);
 496             return;
 497         }
 498
 499         list($top, $right, $bottom, $left) = $widths;
 500
 501         // All this polygon business is for beveled corners...
 502         switch ($side) {
 503             case "top":
 504                 $points = array($x, $y,
 505                     $x + $length, $y,
 506                     $x + $length - $right, $y + $top,
 507                     $x + $left, $y + $top);
 508                 $this->_canvas->polygon($points, $color, null, null, true);
 509                 break;
 510
 511             case "bottom":
 512                 $points = array($x, $y,
 513                     $x + $length, $y,
 514                     $x + $length - $right, $y - $bottom,
 515                     $x + $left, $y - $bottom);
 516                 $this->_canvas->polygon($points, $color, null, null, true);
 517                 break;
 518
 519             case "left":
 520                 $points = array($x, $y,
 521                     $x, $y + $length,
 522                     $x + $left, $y + $length - $bottom,
 523                     $x + $left, $y + $top);
 524                 $this->_canvas->polygon($points, $color, null, null, true);
 525                 break;
 526
 527             case "right":
 528                 $points = array($x, $y,
 529                     $x, $y + $length,
 530                     $x - $right, $y + $length - $bottom,
 531                     $x - $right, $y + $top);
 532                 $this->_canvas->polygon($points, $color, null, null, true);
 533                 break;
 534
 535             default:
 536                 return;
 537         }
 538     }
 539
 540     protected function _apply_ratio($side, $ratio, $top, $right, $bottom, $left, &$x, &$y, &$length, &$r1, &$r2)
 541     {
 542         switch ($side) {
 543
 544             case "top":
 545                 $r1 -= $left * $ratio;
 546                 $r2 -= $right * $ratio;
 547                 $x += $left * $ratio;
 548                 $y += $top * $ratio;
 549                 $length -= $left * $ratio + $right * $ratio;
 550                 break;
 551
 552             case "bottom":
 553                 $r1 -= $right * $ratio;
 554                 $r2 -= $left * $ratio;
 555                 $x += $left * $ratio;
 556                 $y -= $bottom * $ratio;
 557                 $length -= $left * $ratio + $right * $ratio;
 558                 break;
 559
 560             case "left":
 561                 $r1 -= $top * $ratio;
 562                 $r2 -= $bottom * $ratio;
 563                 $x += $left * $ratio;
 564                 $y += $top * $ratio;
 565                 $length -= $top * $ratio + $bottom * $ratio;
 566                 break;
 567
 568             case "right":
 569                 $r1 -= $bottom * $ratio;
 570                 $r2 -= $top * $ratio;
 571                 $x -= $right * $ratio;
 572                 $y += $top * $ratio;
 573                 $length -= $top * $ratio + $bottom * $ratio;
 574                 break;
 575
 576             default:
 577                 return;
 578
 579         }
 580     }
 581
 582     protected function _border_double($x, $y, $length, $color, $widths, $side, $corner_style = "bevel", $r1 = 0, $r2 = 0)
 583     {
 584         list($top, $right, $bottom, $left) = $widths;
 585
 586         $third_widths = array($top / 3, $right / 3, $bottom / 3, $left / 3);
 587
 588         // draw the outer border
 589         $this->_border_solid($x, $y, $length, $color, $third_widths, $side, $corner_style, $r1, $r2);
 590
 591         $this->_apply_ratio($side, 2 / 3, $top, $right, $bottom, $left, $x, $y, $length, $r1, $r2);
 592
 593         $this->_border_solid($x, $y, $length, $color, $third_widths, $side, $corner_style, $r1, $r2);
 594     }
 595
 596     protected function _border_groove($x, $y, $length, $color, $widths, $side, $corner_style = "bevel", $r1 = 0, $r2 = 0)
 597     {
 598         list($top, $right, $bottom, $left) = $widths;
 599
 600         $half_widths = array($top / 2, $right / 2, $bottom / 2, $left / 2);
 601
 602         $this->_border_inset($x, $y, $length, $color, $half_widths, $side, $corner_style, $r1, $r2);
 603
 604         $this->_apply_ratio($side, 0.5, $top, $right, $bottom, $left, $x, $y, $length, $r1, $r2);
 605
 606         $this->_border_outset($x, $y, $length, $color, $half_widths, $side, $corner_style, $r1, $r2);
 607
 608     }
 609
 610     protected function _border_ridge($x, $y, $length, $color, $widths, $side, $corner_style = "bevel", $r1 = 0, $r2 = 0)
 611     {
 612         list($top, $right, $bottom, $left) = $widths;
 613
 614         $half_widths = array($top / 2, $right / 2, $bottom / 2, $left / 2);
 615
 616         $this->_border_outset($x, $y, $length, $color, $half_widths, $side, $corner_style, $r1, $r2);
 617
 618         $this->_apply_ratio($side, 0.5, $top, $right, $bottom, $left, $x, $y, $length, $r1, $r2);
 619
 620         $this->_border_inset($x, $y, $length, $color, $half_widths, $side, $corner_style, $r1, $r2);
 621
 622     }
 623
 624     protected function _tint($c)
 625     {
 626         if (!is_numeric($c))
 627             return $c;
 628
 629         return min(1, $c + 0.16);
 630     }
 631
 632     protected function _shade($c)
 633     {
 634         if (!is_numeric($c))
 635             return $c;
 636
 637         return max(0, $c - 0.33);
 638     }
 639
 640     protected function _border_inset($x, $y, $length, $color, $widths, $side, $corner_style = "bevel", $r1 = 0, $r2 = 0)
 641     {
 642         switch ($side) {
 643             case "top":
 644             case "left":
 645                 $shade = array_map(array($this, "_shade"), $color);
 646                 $this->_border_solid($x, $y, $length, $shade, $widths, $side, $corner_style, $r1, $r2);
 647                 break;
 648
 649             case "bottom":
 650             case "right":
 651                 $tint = array_map(array($this, "_tint"), $color);
 652                 $this->_border_solid($x, $y, $length, $tint, $widths, $side, $corner_style, $r1, $r2);
 653                 break;
 654
 655             default:
 656                 return;
 657         }
 658     }
 659
 660     protected function _border_outset($x, $y, $length, $color, $widths, $side, $corner_style = "bevel", $r1 = 0, $r2 = 0)
 661     {
 662         switch ($side) {
 663             case "top":
 664             case "left":
 665                 $tint = array_map(array($this, "_tint"), $color);
 666                 $this->_border_solid($x, $y, $length, $tint, $widths, $side, $corner_style, $r1, $r2);
 667                 break;
 668
 669             case "bottom":
 670             case "right":
 671                 $shade = array_map(array($this, "_shade"), $color);
 672                 $this->_border_solid($x, $y, $length, $shade, $widths, $side, $corner_style, $r1, $r2);
 673                 break;
 674
 675             default:
 676                 return;
 677         }
 678     }
 679
 680     // Draws a solid, dotted, or dashed line, observing the border radius
 681     protected function _border_line($x, $y, $length, $color, $widths, $side, $corner_style = "bevel", $pattern_name, $r1 = 0, $r2 = 0)
 682     {
 683         list($top, $right, $bottom, $left) = $widths;
 684
 685         $width = $$side;
 686         $pattern = $this->_get_dash_pattern($pattern_name, $width);
 687
 688         $half_width = $width / 2;
 689         $r1 -= $half_width;
 690         $r2 -= $half_width;
 691         $adjust = $r1 / 80;
 692         $length -= $width;
 693
 694         switch ($side) {
 695             case "top":
 696                 $x += $half_width;
 697                 $y += $half_width;
 698
 699                 if ($r1 > 0) {
 700                     $this->_canvas->arc($x + $r1, $y + $r1, $r1, $r1, 90 - $adjust, 135 + $adjust, $color, $width, $pattern);
 701                 }
 702
 703                 $this->_canvas->line($x + $r1, $y, $x + $length - $r2, $y, $color, $width, $pattern);
 704
 705                 if ($r2 > 0) {
 706                     $this->_canvas->arc($x + $length - $r2, $y + $r2, $r2, $r2, 45 - $adjust, 90 + $adjust, $color, $width, $pattern);
 707                 }
 708                 break;
 709
 710             case "bottom":
 711                 $x += $half_width;
 712                 $y -= $half_width;
 713
 714                 if ($r1 > 0) {
 715                     $this->_canvas->arc($x + $r1, $y - $r1, $r1, $r1, 225 - $adjust, 270 + $adjust, $color, $width, $pattern);
 716                 }
 717
 718                 $this->_canvas->line($x + $r1, $y, $x + $length - $r2, $y, $color, $width, $pattern);
 719
 720                 if ($r2 > 0) {
 721                     $this->_canvas->arc($x + $length - $r2, $y - $r2, $r2, $r2, 270 - $adjust, 315 + $adjust, $color, $width, $pattern);
 722                 }
 723                 break;
 724
 725             case "left":
 726                 $y += $half_width;
 727                 $x += $half_width;
 728
 729                 if ($r1 > 0) {
 730                     $this->_canvas->arc($x + $r1, $y + $r1, $r1, $r1, 135 - $adjust, 180 + $adjust, $color, $width, $pattern);
 731                 }
 732
 733                 $this->_canvas->line($x, $y + $r1, $x, $y + $length - $r2, $color, $width, $pattern);
 734
 735                 if ($r2 > 0) {
 736                     $this->_canvas->arc($x + $r2, $y + $length - $r2, $r2, $r2, 180 - $adjust, 225 + $adjust, $color, $width, $pattern);
 737                 }
 738                 break;
 739
 740             case "right":
 741                 $y += $half_width;
 742                 $x -= $half_width;
 743
 744                 if ($r1 > 0) {
 745                     $this->_canvas->arc($x - $r1, $y + $r1, $r1, $r1, 0 - $adjust, 45 + $adjust, $color, $width, $pattern);
 746                 }
 747
 748                 $this->_canvas->line($x, $y + $r1, $x, $y + $length - $r2, $color, $width, $pattern);
 749
 750                 if ($r2 > 0) {
 751                     $this->_canvas->arc($x - $r2, $y + $length - $r2, $r2, $r2, 315 - $adjust, 360 + $adjust, $color, $width, $pattern);
 752                 }
 753                 break;
 754         }
 755     }
 756
 757     protected function _set_opacity($opacity)
 758     {
 759         if (is_numeric($opacity) && $opacity <= 1.0 && $opacity >= 0.0) {
 760             $this->_canvas->set_opacity($opacity);
 761         }
 762     }
 763
 764     protected function _debug_layout($box, $color = "red", $style = array())
 765     {
 766         $this->_canvas->rectangle($box[0], $box[1], $box[2], $box[3], Color::parse($color), 0.1, $style);
 767     }
 768 }