PHP实现生成推广海报的方法详解

/**
 * 生成宣传海报
 * @param array  参数,包括图片和文字
 * @param string  $filename 生成海报文件名,不传此参数则不生成文件,直接输出图片
 * @return [type] [description]
 */
function createPoster($config=array(),$filename=""){
  //如果要看报什么错，可以先注释调这个header
  if(empty($filename)) header("content-type: image/png");
  $imageDefault = array(
    'left'=>0,
    'top'=>0,
    'right'=>0,
    'bottom'=>0,
    'width'=>100,
    'height'=>100,
    'opacity'=>100
  );
  $textDefault = array(
    'text'=>'',
    'left'=>0,
    'top'=>0,
    'fontSize'=>32,       //字号
    'fontColor'=>'255,255,255', //字体颜色
    'angle'=>0,
  );
  $background = $config['background'];//海报最底层得背景
  //背景方法
  $backgroundInfo = getimagesize($background);
  $backgroundFun = 'imagecreatefrom'.image_type_to_extension($backgroundInfo[2], false);
  $background = $backgroundFun($background);
  $backgroundWidth = imagesx($background);  //背景宽度
  $backgroundHeight = imagesy($background);  //背景高度
  $imageRes = imageCreatetruecolor($backgroundWidth,$backgroundHeight);
  $color = imagecolorallocate($imageRes, 0, 0, 0);
  imagefill($imageRes, 0, 0, $color);
  // imageColorTransparent($imageRes, $color);  //颜色透明
  imagecopyresampled($imageRes,$background,0,0,0,0,imagesx($background),imagesy($background),imagesx($background),imagesy($background));
  //处理了图片
  if(!empty($config['image'])){
    foreach ($config['image'] as $key => $val) {
      $val = array_merge($imageDefault,$val);
      $info = getimagesize($val['url']);
      $function = 'imagecreatefrom'.image_type_to_extension($info[2], false);
      if($val['stream']){   //如果传的是字符串图像流
        $info = getimagesizefromstring($val['url']);
        $function = 'imagecreatefromstring';
      }
      $res = $function($val['url']);
      $resWidth = $info[0];
      $resHeight = $info[1];
      //建立画板 ，缩放图片至指定尺寸
      $canvas=imagecreatetruecolor($val['width'], $val['height']);
      imagefill($canvas, 0, 0, $color);
      //关键函数，参数（目标资源，源，目标资源的开始坐标x,y, 源资源的开始坐标x,y,目标资源的宽高w,h,源资源的宽高w,h）
      imagecopyresampled($canvas, $res, 0, 0, 0, 0, $val['width'], $val['height'],$resWidth,$resHeight);
      $val['left'] = $val['left']<0?$backgroundWidth- abs($val['left']) - $val['width']:$val['left'];
      $val['top'] = $val['top']<0?$backgroundHeight- abs($val['top']) - $val['height']:$val['top'];
      //放置图像
      imagecopymerge($imageRes,$canvas, $val['left'],$val['top'],$val['right'],$val['bottom'],$val['width'],$val['height'],$val['opacity']);//左，上，右，下，宽度，高度，透明度
    }
  }
  //处理文字
  if(!empty($config['text'])){
    foreach ($config['text'] as $key => $val) {
      $val = array_merge($textDefault,$val);
      list($R,$G,$B) = explode(',', $val['fontColor']);
      $fontColor = imagecolorallocate($imageRes, $R, $G, $B);
      $val['left'] = $val['left']<0?$backgroundWidth- abs($val['left']):$val['left'];
      $val['top'] = $val['top']<0?$backgroundHeight- abs($val['top']):$val['top'];
      imagettftext($imageRes,$val['fontSize'],$val['angle'],$val['left'],$val['top'],$fontColor,$val['fontPath'],$val['text']);
    }
  }
  //生成图片
  if(!empty($filename)){
    $res = imagejpeg ($imageRes,$filename,90); //保存到本地
    imagedestroy($imageRes);
    if(!$res) return false;
    return $filename;
  }else{
    imagejpeg ($imageRes);     //在浏览器上显示
    imagedestroy($imageRes);
  }
}

$config = array(
  'image'=>array(
    array(
      'url'=>'qrcode/qrcode.png',     //二维码资源
      'stream'=>0,
      'left'=>116,
      'top'=>-216,
      'right'=>0,
      'bottom'=>0,
      'width'=>178,
      'height'=>178,
      'opacity'=>100
    )
  ),
  'background'=>'bg/bg1.jpg'          //背景图
);
$filename = 'bg/'.time().'.jpg';
//echo createPoster($config,$filename);
echo createPoster($config);

$config = array(
  'text'=>array(
    array(
      'text'=>'昵称',
      'left'=>182,
      'top'=>105,
      'fontPath'=>'qrcode/simhei.ttf',     //字体文件
      'fontSize'=>18,             //字号
      'fontColor'=>'255,0,0',       //字体颜色
      'angle'=>0,
    )
  ),
  'image'=>array(
    array(
      'url'=>'qrcode/qrcode.png',       //图片资源路径
      'left'=>130,
      'top'=>-140,
      'stream'=>0,             //图片资源是否是字符串图像流
      'right'=>0,
      'bottom'=>0,
      'width'=>150,
      'height'=>150,
      'opacity'=>100
    ),
    array(
      'url'=>'https://wx.qlogo.cn/mmopen/vi_32/DYAIOgq83eofD96opK97RXwM179G9IJytIgqXod8jH9icFf6Cia6sJ0fxeILLMLf0dVviaF3SnibxtrFaVO3c8Ria2w/0',
      'left'=>120,
      'top'=>70,
      'right'=>0,
      'stream'=>0,
      'bottom'=>0,
      'width'=>55,
      'height'=>55,
      'opacity'=>100
    ),
  ),
  'background'=>'qrcode/bjim.jpg',
);
$filename = 'qrcode/'.time().'.jpg';
//echo createPoster($config,$filename);
echo createPoster($config);