https://qooah.com/2012/09/01/samsung-s-pen-sdk-%e6%9b%b4%e6%96%b0%e5%88%b0-2-2-%ef%bc%8c%e5%b0%87%e6%94%af%e6%8f%b4%e6%9b%b4%e5%a4%9a%e5%8a%9f%e8%83%bd%e3%80%81%e5%8a%a0%e5%85%a5%e6%87%b8%e6%b5%ae%e9%96%8b%e5%95%9f%e6%87%89/