如何用PHP旋转SVG

我搜索了很长一段时间，终于把这些放在了一起。希望能有所帮助。

您可以根据需要使用SimpleXML库来访问节点。

我的解决方案有效，但可能会简化。

首先，我添加了这个类（可以在这里的评论中找到）：

class ExSimpleXMLElement extends SimpleXMLElement 
{ 

    public function _construct($xml){
        parent::_construct($xml);
    }
    /** 
     * Add SimpleXMLElement code into a SimpleXMLElement 
     * @param SimpleXMLElement $append 
     */ 
    public function appendXML($append) 
    { 
        if ($append) { 
            if (strlen(trim((string) $append))==0) { 
                $xml = $this->addChild($append->getName()); 
                foreach($append->children() as $child) { 
                    $xml->appendXML($child); 
                } 
            } else { 
                $xml = $this->addChild($append->getName(), (string) $append); 
            }     
            foreach($append->attributes() as $n => $v) { 
                $xml->addAttribute($n, $v); 
            } 
         } 
     } 
} 

只需将其包含在任何代码之前。

//file
$file = 'svg-nog.svg';
//http://www.webdeveloper.com/forum/showthread.php?165648-Editing-XML-using-PHP
$xml = simplexml_load_file($file); //Load the File. 
$sxe = new EXSimpleXMLElement($xml->asXML()); //Load the child class (it will load the main one)
// Get the parent node's childrens
$nodeChildrens = $sxe->children();
//Check if there's more than one child and if there is more than one <g> tag
if(count($nodeChildrens) > 1 and count($sxe->g) > 1){
//Add our Wrapper Node
$g = $sxe->addChild("g");
//You can go ahead and add your desired transform code
$g['transform'] = "rotate(90 600 600)";
//Set an ID so it's unique
$g['id'] = "myWrapper";
$unsets = array();
//Loop through the children
foreach ($nodeChildrens as $value) {
            //Skip our wrapper element
    if($value->attributes()->id == "myWrapper"){
        continue;
    }
            //Append the element to the wrapper
            //Will recursively add elements as needed
    $g->appendXML($value);
    //Save a reference for the different elements we have
    $unsets[] = $value->getName();
}   
//Loop through the old/loose elements and remove them
foreach ($unsets as $name) {
    $segarr = $sxe->{$name};
    $count = count($segarr);
    $j = 0;
    for ($i = 0; $i < $count; $i++) {
        if ($segarr[$j]['id'] != 'myWrapper') {
            unset($segarr[$j]);
            $j = $j - 1;
        }
        $j = $j + 1;
    }
}
} else {
    //Just apply the transform
    $sxe->g['transform'] = "rotate(90 600 600)";
        //Can also be done with:
        //$sxe->g->addAttribute('transform', "rotate(90 600 600)");
}
//Save
$sxe->asXML('test.svg');

这对我来说非常有效，既适用于包装在标签中的SVG，也适用于未包装的SVG。也许有更简单的方法可以做到这一点，但这肯定是有效的。

还有一件事这可能不正确，但当我旋转SVG时，它们通常会被剪切。因此，我不得不改变主要属性。这需要交换高度和宽度，以及转换SVG以重新居中

//Set the vars of the primary attributes we want to edit
$w = "width";
$h= "height";
$viewbox = "viewBox";
$bg = 'enable-background';
//Get SVG Width & Height
$width = (string)$sxe->attributes()->$w;
$height = (string)$sxe->attributes()->$h;
//Get viewBox and background
$sxe->attributes()->$viewbox = "0 0 " . str_replace('px', '', $height) . " " . str_replace('px', '', $width);
$sxe->attributes()->$bg = "new 0 0 " . str_replace('px', '', $height) . " " . str_replace('px', '', $width);
//Get the numerical values for width and height
$rw = floatval(str_replace("px", "", $width));
$rh = floatval(str_replace("px", "", $height));
//Get the center point
$rx = $rw / 2;
$ry = $rh / 2;
//Logic will determine the appropiate translate value for the svg so that it will center in the new viewbox
if($rw < $rh){
    $trans = ($rw - $rh) / 2;
}
if($rw > $rh){
    $trans = -1 * ($rh - $rw) / 2;
}
//Swap width and height
$oldW = (string)$sxe->attributes()->$w;
$sxe->attributes()->$w = $height;
$sxe->attributes()->$h = $oldW;

// Get the parents node childrens
$nodeChildrens = $sxe->children();
//If the transform attribute is set, this svg has already been rotated, as such, we'll just unset it
if(isset($nodeChildrens->g->attributes()->transform)){
    unset($nodeChildrens->g->attributes()->transform);
} else {
    // Otherwise, we're going to add in the transform data for the rotation and re-centering.
    $nodeChildrens->g->addAttribute('transform', "rotate(90 ".$rx." ".$ry.") translate(".$trans." ".$trans.")");
}
//This next line will overwrite the original XML file with new data added 
$sxe->asXML("test.svg");

您可能会注意到，在底部，此代码也将反转旋转过程。

希望能有所帮助！