After all Subshaders a Fallback can be defined. It basically says “if none of subshadersEach shader in Unity consists of a list of subshaders. When Unity has to display a mesh, it will find the shader to use, and pick the first subshader that runs on the user’s graphics card. More info
See in Glossary can run on this hardware, try using the ones from another shaderA small script that contains the mathematical calculations and algorithms for calculating the Color of each pixel rendered, based on the lighting input and the Material configuration. More info
See in Glossary”.
Fallback "name"
Fallback to shader with a given name or…
Fallback Off
Explicitly state that there is no fallback and no warning should be printed, even if no subshaders can run on this hardware.
A fallback statement has the same effect as if all subshaders from the other shader would be inserted into its place.
Shader "example" {
// properties and subshaders here...
Fallback "otherexample"
}