PHP 生成圆角图片

public function radius_img($imgpath,$outpath) {
$radius = 200;
$ext     = pathinfo($imgpath);
$src_img = null;

switch ($ext['extension']) {
case 'jpg':
$src_img = imagecreatefromjpeg($imgpath);
break;
case 'png':
$src_img = imagecreatefrompng($imgpath);
break;
}

$wh = getimagesize($imgpath);
$w  = $wh[0];
$h  = $wh[1];
// $radius = $radius == 0 ? (min($w, $h) / 2) : $radius;
$img = imagecreatetruecolor($w, $h);
//这一句一定要有
imagesavealpha($img, true);
//拾取一个完全透明的颜色,最后一个参数127为全透明
$bg = imagecolorallocatealpha($img, 255, 255, 255, 127);
imagefill($img, 0, 0, $bg);
$r = $radius; //圆 角半径
for ($x = 0; $x < $w; $x++) {
for ($y = 0; $y < $h; $y++) {
$rgbColor = imagecolorat($src_img, $x, $y);
if (($x >= $radius && $x <= ($w - $radius)) || ($y >= $radius && $y <= ($h - $radius))) {
//不在四角的范围内,直接画
imagesetpixel($img, $x, $y, $rgbColor);
} else {
//在四角的范围内选择画
//上左
$y_x = $r; //圆心X坐标
$y_y = $r; //圆心Y坐标
if (((($x - $y_x) * ($x - $y_x) + ($y - $y_y) * ($y - $y_y)) <= ($r * $r))) {
imagesetpixel($img, $x, $y, $rgbColor);
}
//上右
$y_x = $w - $r; //圆心X坐标
$y_y = $r; //圆心Y坐标
if (((($x - $y_x) * ($x - $y_x) + ($y - $y_y) * ($y - $y_y)) <= ($r * $r))) {
imagesetpixel($img, $x, $y, $rgbColor);
}
//下左
$y_x = $r; //圆心X坐标
$y_y = $h - $r; //圆心Y坐标
if (((($x - $y_x) * ($x - $y_x) + ($y - $y_y) * ($y - $y_y)) <= ($r * $r))) {
imagesetpixel($img, $x, $y, $rgbColor);
}
//下右
$y_x = $w - $r; //圆心X坐标
$y_y = $h - $r; //圆心Y坐标
if (((($x - $y_x) * ($x - $y_x) + ($y - $y_y) * ($y - $y_y)) <= ($r * $r))) {
imagesetpixel($img, $x, $y, $rgbColor);
}
}
}
}
header("content-type:image/jpeg");
imagepng($img,$outpath);
}