How can i use struct uniform variable in unity cg/hlsl?

Question

I want make vertex-fragment shader in unity. I know about GLSL, but first try for cg/hlsl programming.

if i setting unity to 'graphic API for openGLCore', i can use struct uniform variables. uniform variable mean, shader properties. (glsl call it uniform)

but i setting unity to 'graphic API for Direct3D', it cant work. compile error.

this is error.

    Shader error in 'HLSL/Phong_cg': Fragment program 'frag': Struct variable 
    'u_material' is ignored. Only instancing constant buffers can have struct 
    variables (on d3d11)

this is code.

        struct MATERIAL {
            fixed4 ambient_color;
            fixed4 diffuse_color;
            fixed4 specular_color;
            fixed4 emissive_color;
            float specular_exponent;
        };
        uniform MATERIAL u_material;

I can't find how to solve. if i use struct in function(local varialble), it has no problem. but i need global(uniform)....

it's impossible?

ps. in cg/hlsl, this 'uniform variable' called what? it's just properties?

Kalle Halvarsson Kalle Halvarsson · Accepted Answer · 2019-02-11T07:54:43

In Unity, uniforms are linked through a material property block. What you need to do is to first define them as properties, and then define them again in the CGPROGRAM block to make them available in the shader code. Unity materials remember all properties set across all used shaders as key-value-pairs and will try to fit these in where they match.

Shader "Name" {
    Properties {
        _MyProperty1("Texture Name", 2D) = "white{}
        _MyProperty2("Color name", Color) = (1, 1, 1, 1)
        _MyRangeProperty("Float with a slider range", Range(0, 1)) = 0
        _MyVectorProperty("Vector name", Vector) = (0, 0, 0, 0)
    }

    SubShader {
        Pass {
            CGPROGRAM

            sampler2D _MyProperty1;
            fixed4 _MyProperty2;
            half _MyRangeProperty;
            float4 _MyVectorProperty;

            ENDCG
        }

    }

}

How can i use struct uniform variable in unity cg/hlsl?

2 Answers