(PHP 4 >= 4.0.6, PHP 5)
imagesetthickness — Set the thickness for line drawing
imagesetthickness() sets the thickness of the lines drawn when drawing rectangles, polygons, ellipses etc. etc. to thickness pixels.
An image resource, returned by one of the image creation functions, such as imagecreatetruecolor().
如果成功則回傳 TRUE,失敗則回傳 FALSE。
Note: 本函式需要 GD 2.0.1 或更高版本(推薦 2.0.28 及更高版本)。