"Shader error redefinition of 'Varyings'" error appears when selecting the shader

It looks like the shader needs few fixes to work with no errors: * struct Varyings {...} needs a ";" at the end of it. * You're using: #pragma vertex MeshCloudVertex but then you have Varyings Vertex(Attributes IN) { Varyings OUT = (Varyings)0; OUT.color.w = ComputeFogFactor(OUT.positionHCS.z); } The compiler looks for a function named MeshCloudVertex (because of the #pragma vertex line). But you’ve actually defined Vertex. Because of this mismatch, Unity falls back to some default behavior during compilation and re-parses Varyings in a way that leads to a duplicate structure definition in the generated code for Metal. So the user should either change the pragma to "#pragma vertex Vertex" or rename their function to "Varyings MeshCloudVertex". * Also the function is missing a return value of type Varyings -> Add "return OUT;" at the end of the function.

It looks like the shader needs few fixes to work with no errors: * struct Varyings {...} needs a ";" at the end of it. * You're using: #pragma vertex MeshCloudVertex but then you have Varyings Vertex(Attributes IN) { Varyings OUT = (Varyings)0; OUT.color.w = ComputeFogFactor(OUT.positionHCS.z); } The compiler looks for a function named MeshCloudVertex (because of the #pragma vertex line). But you’ve actually defined Vertex. Because of this mismatch, Unity falls back to some default behavior during compilation and re-parses Varyings in a way that leads to a duplicate structure definition in the generated code for Metal. So the user should either change the pragma to "#pragma vertex Vertex" or rename their function to "Varyings MeshCloudVertex". * Also the function is missing a return value of type Varyings -> Add "return OUT;" at the end of the function.