Shader coloring

At present, The display effect of VC model is not as realistic as I want. I hope the following functions can be supported in the development:
1 Support the development of shader coloring language(It’s a very urgent demand.)
2 Support vertex shader, geometry shader and pixel shader
3 Support for multiple pass rendering
4 Support off screen rendering and post-processing
What should I do? Please give me a hand.

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