php实现简易合成图片方法

//生成二维码function qr_user_code($url_code,$uid){
    header("Access-Control-Allow-Origin:*");
    vendor('phpqrcode.phpqrcode');//引用phpqrcode类包
    $url = $url_code;    $errorCorrectionLevel = 'H';//容错级别
    $matrixPointSize = 5;//图片大小慢慢自己调整，只要是int就行
    $path = 'user_cache/';    if (!file_exists($path)) {
        mkdir($path);
    }    $QR =$QRB = $path.rand(10000,99999).time().".png";
    \QRcode::png($url, $QR, $errorCorrectionLevel, $matrixPointSize, 2);    $dst_path = '20180326171846.png';//web\lALPBbCc1VATaEvNA4DNAnw_636_896.png
    $src_path = $QR;//覆盖图
    //创建图片的实例
    $dst = imagecreatefromstring(file_get_contents($dst_path));    $src = imagecreatefromstring(file_get_contents($src_path));//获取覆盖图图片的宽高
    list($src_w, $src_h) = getimagesize($src_path);//将覆盖图复制到目标图片上，最后个参数100是设置透明度（100是不透明），这里实现不透明效果
    imagecopymerge($dst, $src, 184, 410, 0, 0, 286, 286, 100);//     @unlink($QIMG); //删除二维码与logo的合成图片
    @unlink($QRB);  //删除服务器上二维码图片
    header("Content-type: image/png");
    imagepng($dst,'uploads/user/'.$uid.'.png');//    imagejpeg($dst,'../uploads/user/'.$uid.'.jpg');
    imagedestroy($dst);
    imagedestroy($src);
}

 public function qr_code($uid){
        $url = 'http://ypyz.yxyzyl.com/template/mobile/xian/static/takehtml/personalhtml/bind.html?uid='.$uid;
        qr_user_code($url,$uid);//因为我封装在common里面的，所以这样调用
        $time = time();        $path = '/uploads/user/'.$uid.'.png';        $sha1 = sha1($uid.$time.'.png');        $res = (new Us())->where(['user_id'=>$uid])->update(['qr_code'=>$sha1]);        $re = db('picture')->insert([            'path'=>$path,            'sha1'=>$sha1,            'status'=>1,            'create_time'=>$time
        ]);        if ($res !== false&&$re!=false) {            $this->assign('path',$path);            return $this->fetch();
        } else {            $this->error('生成二维码失败', '');
        }

    }