Creating Fog Of View in 2D game with lighting method

Question

I'm creating 2D side scrolling game with Unity, and i want to add feature where the player come into a cave, then all going dark, the player turn on the flash light, so the player can see around ( With limited range )

I have done creating that by setting all object color to Black, and if the light is touching the object, the object color turned to White, but the problem is, if just a little of light touching the object, the entire object color turned to white ( No Gradation or something like shading )

so my question is

Is there any suggestion or another method to fix that ?

Answer 1

Maybe i dont understand what you are trying to do, but the standard way to do this is to have a spot light as your flash light. In your case you would disable all lighting sources in the scene and set global ambient lighting to 0. This will make the scene pitch black where only the spot light attached to the player visible.

For 2d you will need to add normals maps to your sprites. this tutorial covers this. https://www.codeandweb.com/blog/2015/05/04/2d-dynamic-lighting-tutorial-for-unity.

With normal mapped sprites your sprites can perform lighting calculations with the regular unity lighting system.

Note you dont need normal maps for sprite lighting, if you angle the spot light correctly you will still light up your sprites. Unity will use the default normal's for lighting calculations.