I created a tool that automates the setup and management of a multi-camera -> render texture system for our game. We did this so that we could have apply effects like transparency, dissolves, and outlines to our Spine assets. It worked so well for us that I extracted the code out into a standalone package.

Source: https://github.com/aflesher/EntityPostProcessor2D
Package: https://drive.google.com/open?id=1-eA-qDG59Q6EsTLXh0prcmobsTHtuyp5

There are a few drawbacks to this system. There is some performance overhead because you are adding an extra draw call for every asset you want to use this tool on. You also won't be able to use this with environmental lighting. This is because the assets are placed off screen and rendered back onto a texture on screen. I've been trying to come up with a solution for this but haven't yet.

Anyways, it's free to use so enjoy. If people actually find this useful I'll add some better effects. The ones I included were really just the bare minimum to demonstrate how it works.

I'll look into this, I see that rendering to a SpriteRenderer could be useful.

Unfortunately, I don't have the 2dxfx package but I have a feeling it could easily work with a camera or mesh renderer/quad.

Anyways, I'll respond to this once I have an update.

I took a look at compatibility with 2DxFX. I more or less got it working. You'll need to download a newer version of the tool which you can get from the links in the original post.

There are details at the bottom of https://github.com/aflesher/EntityPostProcessor2D on how to get this working. I tried about 5 different effects and they all worked after doing a search and replace for SpriteRenderer/MeshRenderer. It's not a perfect solution but hopefully it helps.

There were a few issues with this tool that have been resolved. Download the newest package and these issues should be resolved.

Also, I created a video to demonstrate how to setup Spine + 2DxFx. Hope this adds some clarity.

That's a great question Pharan. I actually set out to see if it was possible to render to a SpriteRenderer instead of MeshRenderer but it's not really feasible.

The issue is that a SpriteRenderer requires a Texture2D but a camera, when rendered to a texture, creates a RenderTexture. Converting a RenderTexture to a Texture2D is a pretty heavy operation and only supported by graphics cards that have copyTexture https://docs.unity3d.com/ScriptReference/Rendering.CopyTextureSupport.html

That's not to say that I couldn't add the option to render to a SpriteRenderer. But it would need warning information stating that this is a really inefficient approach and should be avoided if possible. I think anyone that is serious about the performance of their game would be wise to try and modify any effects to work with a MeshRenderer instead.