因为客户上传的商品图大小不一,所以加了一个原图裁剪方法 mkThumbnail (代码参考另一篇文章 https://www.cnblogs.com/gyrgyr/p/13726317.html )
生成图示例:(背景尺寸1066*1599)

public function getActivityImg($logo='',$template,$url,$goods_info)
{
$price = empty($goods_info['sg_vip_price']) || $goods_info['sg_vip_price']==0 ?$goods_info['sg_price']:$goods_info['sg_vip_price']; //商品价格
$QR = "base.png";
$last = "last.png";
$errorCorrectionLevel = 'Q'; //防错等级
$matrixPointSize = 3; //二维码大小
//二维码位置
$x = 815;
$y = 625;
//生成二维码
//参数内容:二维码储存内容,生成存储,防错等级,二维码大小,白边大小
Vendor('phpqrcode.phpqrcode');
$object = new QRcode();
$object->png($url, $QR, $errorCorrectionLevel, $matrixPointSize, 1);
$last = $QR;
//合成二维码图片跟 模板图片
$path_1 = $template; //背景图
$path_2 = $last; //二维码图
$dst = imagecreatefromstring(file_get_contents($path_1));
$src = imagecreatefromstring(file_get_contents($path_2));
list($src_w, $src_h) = getimagesize($path_2);
imagecopymerge($dst, $src, $x, $y, 0, 0, $src_w, $src_h, 100);
//商品图片缩放为新图片
$EchoPath='./share_cod/-'.rand(99).time().'.png';
$r = $this->mkThumbnail($goods_info['sg_img_url'],'418','408',$EchoPath);
//商品图位置
$goods_x = 176;
$goods_y = 937;
//合并商品图 与 二维码带背景
$path_2 = $EchoPath; //商品图
$src = imagecreatefromstring(file_get_contents($path_2));
list($src_w, $src_h) = getimagesize($path_2);
imagecopymerge($dst, $src, $goods_x, $goods_y, 0, 0, $src_w, $src_h, 100);
//打上文字 商品名称
$font = '/usr/share/fonts/chinese/msyhbd.ttf';
$g_name = mb_substr($goods_info['sg_name'],0,10,'utf-8').'...';
/*
这块注释的是原来设计图文字是居中的,具体文字数量不确定,所以计算的居中位置,后来改为靠右,有了具体尺寸就不用了
$fontBox = imagettfbbox(33, 0, $font, $g_name);
$textx = ceil((896 - $fontBox[2]) / 2 ); //计算居中位置
$black = imagecolorallocate($dst, 0x00, 0x00, 0x00);//字体
$black = imagecolorallocate($dst, 0x00, 0x00, 0x00);//字体
imagefttext($dst, 33, 0, $textx, 290, $black, $font, $g_name);//字体颜色
*/
$black = imagecolorallocate($dst, 254, 243, 222);//字体
imagefttext($dst, 50, 0, 370, 270, $black, $font, $g_name);//字体颜色
//打上文字 原价
$black = imagecolorallocate($dst, 231,162,115);//字体
imagefttext($dst, 30, 0, 552, 388, $black, $font, intval($goods_info['sg_y_price']));//字体颜色
//打上文字 价格
$black = imagecolorallocate($dst, 255,255,255);//字体
imagefttext($dst, 35, 0, 810, 388, $black, $font, intval($price));//字体颜色
//打上文字 卖点
$black = imagecolorallocate($dst, 255, 255, 255);//字体
imagefttext($dst, 38, 0, 399, 530, $black, $font, $goods_info['sg_describe']);//字体颜色
//输出图片
list($dst_w, $dst_h, $dst_type) = getimagesize($path_1);
switch ($dst_type) {
case 1://GIF
$typ = 'gif';
break;
case 2://JPG
$typ = 'jpg';
break;
case 3://PNG
$typ = 'png';
break;
default:
break;
}
//输出到本地文件夹,返回生成图片的路径
$fileName= get_mpid().'_'.$goods_info['sg_id'].time();
$EchoPath='./Images/share_img/'.$fileName.'.'.$typ;
imagepng($dst,$EchoPath);
imagedestroy($dst);
imagedestroy($src);
return $EchoPath;
}