houdini p18

entagma p18

if(inpointgroup(0,'active',@ptnum)){
float x,y,z,a,b,c,d,e,k,f,dt;
vector pos = set(0,0,0);
dt = 0.001;
a = 40;
c = 1.833;
d = 0.16;
e = 0.65;
k = 55;
f = 20;

pos = @P;
x = pos[0];
y = pos[1];
z = pos[2];

x = x+(a*(y-x)+d*x*z)*dt;
y = y+(k*x+f*y-x*z)*dt;
z = z+(c*z + x*y - e*x*x)*dt;
pos = set(x,y,z);
int newpt = addpoint(0,pos);
setpointgroup(0,'active',newpt,1);
setpointgroup(0,'active',@ptnum,0);
addvertex(0,0,newpt);
}