php添加水印 水印平铺整个图片

$bigImgPath = "logo.png"; //原图

$logo = "logo2.png"; //水印

$im = imagecreatefromstring(file_get_contents($bigImgPath));

//获取水印源

$watermark = imagecreatefromstring(file_get_contents($logo));

//获取图、水印 宽高类型

list($bgWidth, $bgHight, $bgType) = getimagesize($bigImgPath);

list($logoWidth, $logoHight, $logoType) = getimagesize($logo);

//定义平铺数据

$x_length = $bgWidth - 10; //x轴总长度

$y_length = $bgHight - 10; //y轴总长度

//创建透明画布 伪白色

$opacity=20;

$w = imagesx($watermark);

$h = imagesy($watermark);

$cut = imagecreatetruecolor($w,$h);

$white = imagecolorallocatealpha($cut, 255,255,255,0);

imagefill( $cut, 0, 0, $white );

//整合水印

imagecopy($cut, $watermark, 0, 0, 0, 0, $w, $h);

//循环平铺水印

for ($x = 0; $x < $x_length; $x) {

for ($y = 0; $y < $y_length; $y) {

imagecopymerge($im, $cut, $x, $y, 0, 0, $logoWidth, $logoHight, $opacity);

$y += $logoHight;

}

$x += $logoWidth;

}

header("Content-type:image/png");

imagejpeg($im);