Strong/thick fog?

[AnimatedT (Tarun)]

@xnihil0zer0

// RayMarchFog CMOT Float 4

float3 lightvec = normalize(float3(0.687334,0.506979,-0.520138));
float stepsize=100;
float numsteps=50;
float mul=0.0;
float4 sum={0,0,0,0};
for(int i=0;i<numsteps;i++)
{
if( sum.a > 1) break;
float rt=stepsizemul(1+(dither/2-0.25));
float3 pos=rtrd+ro;
if(rt>scenedepth) break;
float3 noisepos1=pos.zxy+float3(300t,100sin(t/20),100sin(t/60));
float dens=clamp(MaterialExpressionNoise(noisepos1/500, 0.10000000, 0.00000000, 0.00000000, 1.00000000, 2.00000000, -0.10000000, 1.00000000, 2.00000000, 0.00000000)/3,0,1);
float4 col=float4(dens,dens,dens,dens)fogcol;
float dif=clamp(MaterialExpressionNoise((noisepos1+lightvec100)/500, 0.10000000, 0.00000000, 0.00000000, 1.00000000, 2.00000000, -0.100000000, 1.00000000, 2.00000000, 0.00000000)/3,0,1);
col.xyz+=dif;
col.rgb*=col.a;
sum=sum+col*(1.0-sum.a);
mul+=1.0;
if (mul>49) sum.a=1;
}
return clamp(sum,0,1);

Hi, sorry about brining the dead back but this seems interesting but I’m getting this error.