Crepuscular Rays is an Image Effect used to create Crepuscular Rays.
This goes a little further than the intrinsic Unity3D version, you are able to use your own texture for the light source, you can place it anywhere in a 2D or 3D scene using the intrinsic Lights that come with Unity3D, the effect will use the light’s colour, intensity and scale to render the light source and then from its position render the light rays. You are also able to rotate the source texture.
The Asset comes with both a 3D and a 2D sample showing how it can be used.
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