surface ho_tx3d(
	string tx3d = "";
	string tx3d_temp = "";
	float Kd = 0.8, Ko = 1,tempMult = 0.1;
	color red = color(1,0.5,0),
	dark = color(0.2,0.2,0.2),
	surfColor = color(1,1,1)
){
	normal 	n = normalize(N);
	normal	nf = faceforward(n, I);
	color diffusecolor = Kd * diffuse(nf);
	
	normal n0 = normal(0,0,0);

	float density = 1;
	float success = texture3d(tx3d,P,n0,"smoke",density);
	density = clamp(density,0,1);

	float temp = 1;
	success = texture3d(tx3d_temp,P,n0,"temp",temp);

	color fire = mix(dark,red,temp*tempMult*0.001);
	
	Oi = density * Ko;
	Ci = Oi * diffusecolor*surfColor*fire;
}