I wanted to create the simple double-sided force field shader but stumbled upon a problem with the double-sided rendering of transparent objects.

You can see that the Cull Off shader has some artifacts. On the other hand, the double-sided mesh with the Cull Back shader doesn’t have these artifacts.

I’ve decided to do some research about the ways to render objects from both sides. I want to look into how they work with transparent objects and what approaches can be used in LWRP.

There are several ways to render meshes from both sides:

1. A single-pass Cull Off shader with normals flip on VFACE, if lighting is needed
2. Two-pass shader, the first pass with Cull Front, the second with Cull Back
3. Two Materials Basic material and material with Cull Front and flipped normals
4. Double-sided mesh

All variants except the fourth require shader modifications. The second and the third variants are not supported by LWRP at all, because it doesn’t support the two pass shaders, at least not without some or another magic.

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