1、先获取用户的headimgurl和nickname

2、通过以下方法传入参数生成图片 ，  注意这里的fontPath  下载链接： 微软雅黑.ttf

public 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
			'fontPath' => '/static/fonts/msyh.ttf',
			'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']);
			}
		}
		//保存到本地
		$res = imagejpeg($imageRes,$filename,90);
		imagedestroy($imageRes);
		if(!$res) return false;
		return $filename;
	}

3、设置组合图片 的背景、文字、图片 等 ，注意图片的left和top   这个按背景图上的分辨率来处理

$config = array(
			'image'=>array(
				array(
					'url'=>'http://xjhuanbao.ks0.cn/static/tupian/erweima.png', //二维码资源
					'stream'=>0,
					'left'=>810,
					'top'=>1520,
					'right'=>0,
					'bottom'=>0,
					'width'=>250,
					'height'=>250,
					'opacity'=>100,
				),
				array(
					//'url'=>$useravatar, //用户头像
					'url'=>'http://xjhuanbao.ks0.cn/static/images/default_avatar.png',
					'stream'=>0,
					'left'=>270,
					'top'=>425,
					'right'=>0,
					'bottom'=>0,
					'width'=>130,
					'height'=>130,
					'opacity'=>100,
				),
			),
			'text'=>array(
				array(
					'text'=> $username,
					'left'=> 420,
					'top'=>485,
					'fontSize'=>35,       //字号
					'fontColor'=>'37,139,126', //字体颜色
					'angle'=>0
				),
				array(
					'text'=> $date,
					'left'=> 420,
					'top'=>550,
					'fontSize'=>30,       //字号
					'fontColor'=>'37,139,126', //字体颜色
					'angle'=>0
				),
				array(
					'text'=> "美丽海南 第".$num."位参与者",
					'left'=> 290,
					'top'=>1045,
					'fontSize'=>35,       //字号
					'fontColor'=>'37,139,126', //字体颜色
					'angle'=>0
				)
			),
			'background'=>$bgimg  //背景图
	  );
	createPoster($config, session('openid').'.jpg');