float GetDist(float3 p)
{
    float d = 1e10;
    //sdf shaped and stuff in here
    return d;
}

float3 GetNormal(float3 p)
{
    float2 e = float2(1e-2, 0);
    float3 n = GetDist(p) - float3
    (
    GetDist(p - e.xyy),
    GetDist(p - e.yxy),
    GetDist(p - e.yyx)
    );
return normalize(n);
}

float RayMarch(float3 ro, float3 rd)
{
    float d0 = 0;
    float dS;

    for(int i = 0; i < _MaxSteps; i++)
    {
        float3 p = ro + d0 * rd;
        dS = GetDist(p);
        d0 += dS;
        if(dS <_SurfaceDistance || d0 > _MaxDistance)
        {
            break;
        }
    }
    return d0;
}

fixed4 frag(v2f i) : SV_Target
{
    fixed4 col = 0;

    float3 ro = i.ro;
    float3 rd = normalize(i.hitPos - ro);

    float d = RayMarch(ro, rd);

    if(d >= _MaxDistance)
    {
        discard;
    }
    else
    {
        float3 p = ro + rd * d; //point/position
        float3 N = GetNormal(p); //normal
        float3 L = _WorldSpaceLightPos0.xyz; //direction from mesh to light

        float3 diffuseLight = dot(N, L) * _LightColor0.xyz;

        diffuseLight += _AmbientLight;

        //specular lighting/Bling-Phong
        float3 V = normalize(_WorldSpaceCameraPos - p); //view vector
        float3 H = normalize(L + V);
        float3 specularLight = saturate(dot(H, N));

        float specularExponent = exp2(_Gloss * 6) + 2; //2^Gloss... numbers from freya holmer
        specularLight = pow(specularLight, specularExponent); //specular exponent
        specularLight *= _LightColor0.xyz;

        //composite lights + colors
        col.rgb = diffuseLight * _Color + specularLight;
    }
return col;