Simple 2D light shader in Unity

Lighting in 2D games can be achieved by different means. In Unity you can find nice assets in the asset store or use the 3D classic lights by changing your sprite shader from default to diffuse. What I want to achieve here is a very simple light effect by addding a sprite mask on top of my scene and modify the resulting color in a shader to emulate light like the image below:

Unity basic custom popup Property drawer

With Unity4 came a nice feature : Property drawers.

They allow you to customize the appearance and behavior of your class property and thus create a nice and robust interface in Unity's editor.

One thing I needed when coding my classes was the ability to show a basic popup select list. It allowed me to choose the right behavior for the gameObject depending on this particular field value.