Hello!
I’m trying to write a surface shader that uses a noise texture for vertex displacement. However, I am getting a compile error when trying to do a texture lookup in the ‘vert’ function.
Here is the code for the shader (obviously not finished, don’t point and laugh! 
)
Shader "Test/Noise" {
Properties {
_MainTex ("Texture", 2D) = "white" {}
_NoiseTex("Noise", 2D) = "white" {}
_TimeScale ("Time Scaling", Range(0,10)) = 1.0
_Displacement("Displacement", Range(0,5)) = 1.0
}
SubShader {
Tags { "RenderType" = "Opaque" }
CGPROGRAM
#pragma target 3.0
#pragma surface surf Lambert vertex:vert
float _Sharpness;
float _Displacement;
float _TimeScale;
sampler2D _NoiseTex;
void vert(inout appdata_full v)
{
float2 uvHack = float2(frac(v.vertex.x + v.vertex.y + v.vertex.z),
frac(v.vertex.x * v.vertex.y * v.vertex.z));
float3 noise = tex2D(_NoiseTex,uvHack).rgb;
v.vertex.xyz = v.vertex.xyz - (v.normal.xyz * (noise.x * _Displacement));
}
sampler2D _MainTex;
struct Input {
float2 uv_MainTex;
};
void surf (Input IN, inout SurfaceOutput o) {
o.Albedo = tex2D (_MainTex, IN.uv_MainTex).rgb;
}
ENDCG
}
Fallback "Diffuse"
}
Is it even possible to do this with a surface shader? I’ve never even tried this, and some googling informed me that it is possible (dependant on hardware) if I write out the vertex and fragment shaders separately, but I would like the functionality of using the surface shader to handle lighting.
I’m new to unity/ShaderLab, but I have some experience with CgFX, so I have a fairly good grasp of what is going on, I’m just not sure if what I want to do is possible or not.
