How to achieve 2d lights blocked by the wall

I used the alpha blending method to implement 2d lighting, but I don’t know how to achieve the light blocking by the wall. There is no idea. How can I achieve it,Like right。

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Maybe this could help you out:

Finally, it’s succeed.

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Cool.
Any plans to share that code?

This is a clumsy implementation, using the CPU to calculate the light length and manually updating the depth map, but it has met my game’s needs.It can throw a brick and attract jade to get a better implement, of 2d lighting.

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