File:Trefoil Knot.stl

//https://commons.wikimedia.org/wiki/File:Blue_7_1_Knot.png

r_tube = 0.1;
num_steps = 70;

function pointCord(theta) = [
0.3*( 2*sin(2*theta)-sin(theta) ), 0.3*( 2*cos(2*theta)+cos(theta) ), 0.3*sin(3*theta)
];

module point(N){
  theta = 360 * N / num_steps;
  translate(pointCord(theta))
  sphere(r_tube);
}

for(N=[0:1:num_steps]){
    hull(){
        point(N);
        point(N+1);
    }
}

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