Question about the off screen particle rendering.


I am trying to show the smoke particles in low resolution texture and then blend back with other parts in the scene.
I read the article and make a simple test project in

But unfortunately, the alpha transparent of particle textures seem not working correctly, they are just showing black.
Anyone can help me how to correct this?

Thank you.

I released a version of this technique for free as part of my Unity2015 talk: