openlayers3 (ol3) Magnifying Control

Ispired from official ol3 Layer Spy example, I have made a magnifying custom control.
Make map cursor act as a magnifying lense. Click on M button
This ol3 control is also hosted on gitgub. Here is the link to downlaod (includes example and configuration options).
No dependency on third party libs. Just ol3.
Here is a fiddle