How to hide the alpha of image planes? (Images as Particles)

Question

I'm at the point where I need to add node materials to my leaf branches to make the colors diverse and react well to the lighting. However, whenever I add the mix shader nodes, the blank transparency or the alpha map of the images are exposed.

I was hoping to achieve something like Dragos Matkovski's stylized work in Unity but i'm having a hard time trying to reproduce the same output in blender with the png's alpha showing. I'm using cycles 2.83.

Edit 1: here is my node setup for the images to which the alpha shows.

Edit 2: The answers below helped a ton. Went for a translucent shader + emission instead since the glossy was too strong.

Answer 1

If you want to mix in another (non-principled) material this way, you would have to add transparency to it separately. You could do this with a Transparency material and another mix node, controlled by the image's alpha channel.

However, in your use case, I don't see why you would need another shader, especially not a glossy one - I see nothing like that in the reference image, and it wouldn't be physically accurate. Instead, I would recommend you decrease the roughness of your existing shader if you want more shine.

(Alternatively, you can use the clearcoat settings - these may work well for the natural fats that cover leaves, or to simulate wet leaves.)

Answer 2

Your node tree structure would have to look something like this. The alpha needs to effect all shaders, so make sure to always add an transparency shader at the very end of your tree. But as Reinis already said, there really is no point in mixing the principled shader with a glossy one.