## rendering responsive Images variants
You can use the srcset argument to generate several differently sized
versions of this image that will be added as a srcset argument to the img tag.
enter a list of widths in the srcset to genereate copies of the same crop +
ratio but in the specified widths. Put the width at the start that you want
to use as a fallback to be shown when no srcset functionality is supported.
### Example
### Browser Support
To have the widest Browser-Support you should consider using a polyfill like:
http://scottjehl.github.io/picturefill/
/**
* @return void
*/
public function initializeArguments()
{
parent::initializeArguments();
$this->registerArgument('path', 'string', 'DEPRECATED: Use src instead');
$this->registerArgument('minWidth', 'integer', 'DEPRECATED: Use minW instead');
$this->registerArgument('minHeight', 'integer', 'DEPRECATED: Use minH instead');
$this->registerArgument('maxWidth', 'integer', 'DEPRECATED: Use maxW instead');
$this->registerArgument('maxHeight', 'integer', 'DEPRECATED: Use maxH instead');
$this->registerArgument('density', 'integer', 'Canvas resolution for rendering the PDF in dpi (higher means better quality)', false, 100);
$this->registerArgument('background', 'string', 'Fill background of resulting image with this color (for transparent source files)');
$this->registerArgument('rotate', 'integer', 'Number of degress to rotate resulting image by (caution: very slow if not multiple of 90)', false, 0);
$this->registerArgument('page', 'integer', 'Optional page number to render as thumbnail for PDF documents with multiple pages', false, 1);
$this->registerArgument('forceOverwrite', 'boolean', 'Forcibly overwrite existing converted PDF files', false, false);
}
/**
* @return string
*/
public function render()
{
$path = GeneralUtility::getFileAbsFileName($this->arguments['path']);
if (FALSE === file_exists($path)) {
return NULL;
}
$density = $this->arguments['density'];
$rotate = $this->arguments['rotate'];
$page = intval($this->arguments['page']);
$background = $this->arguments['background'];
$forceOverwrite = (bool) $this->arguments['forceOverwrite'];
$width = $this->arguments['width'];
$height = $this->arguments['height'];
$minWidth = $this->arguments['minWidth'];
$minHeight = $this->arguments['minHeight'];
$maxWidth = $this->arguments['maxWidth'];
$maxHeight = $this->arguments['maxHeight'];
$filename = basename($path);
$pageArgument = $page > 0 ? $page - 1 : 0;
$colorspace = TRUE === isset($GLOBALS['TYPO3_CONF_VARS']['GFX']['colorspace']) ? $GLOBALS['TYPO3_CONF_VARS']['GFX']['colorspace'] : 'RGB';
$destination = GeneralUtility::getFileAbsFileName('typo3temp/vhs-pdf-' . $filename . '-page' . $page . '.png');
if (FALSE === file_exists($destination) || TRUE === $forceOverwrite) {
$arguments = '-colorspace ' . $colorspace;
if (0 < intval($density)) {
$arguments .= ' -density ' . $density;
}
if (0 !== intval($rotate)) {
$arguments .= ' -rotate ' . $rotate;
}
$arguments .= ' "' . $path . '"[' . $pageArgument . ']';
if (NULL !== $background) {
$arguments .= ' -background "' . $background . '" -flatten';
}
$arguments .= ' "' . $destination . '"';
$command = CommandUtility::imageMagickCommand('convert', $arguments);
CommandUtility::exec($command);
}
$image = substr($destination, strlen(PATH_site));
return parent::render($image, $width, $height, $minWidth, $minHeight, $maxWidth, $maxHeight);
}