Unity3D – Lights Cookies

Assign Light Cookie

Light Cookies are grayscale textures you use to control the precise look of in-game lighting.

0. MAIN TOP MENU> GameObject> Create Other> Spotlight, project the light over a plane

1. MAIN TOP MENU> Assets> Import Package> Light Cookies

2. Project> Standard Assets> Light Cookies> FlashLight DRAG AND DROP over Spotlight> Hierarchy> Light> Cookie

Create Light Cookie

To create a light cookie for a spot light:

Paint a cookie texture in Photoshop. The image should be greyscale. White pixels means full lighting intensity, black pixels mean no lighting. The borders of the texture need to be completely black, otherwise the light will appear to leak outside of the spotlight.
In the Texture Inspector change the Texture Type to Cookie
Enable Alpha From Grayscale (this way you can make a grayscale cookie and Unity converts it to an alpha map automatically)