OpenSCADでへノンアトラクタ

henon_map.scad

function map(value, start1, stop1, start2, stop2) =  start2 + (stop2 - start2) * ((value - start1) / (stop1 - start1));

module henon_map(x1, x2, y1, y2, zsize, zpos)
{
    a = 1.4;
    b = 0.3;
    ls = [
        for(i=0, tx=0.0,ty=0.0,x=0.1,y=0.0;i<22000; i=i+1,tx=1-a*x*x+y,ty=b*x,x=tx,y=ty) 
            [i, [map(x, -1.5, 1.5, x1,x2), map(y, -0.5, 0.5, y1,y2), zpos]]
        ];
    for(e = ls)
    {
        if(e[0] > 100) 
            translate(e[1])
                cube([0.05, 0.05, zsize], center=true);
    }
}

color("yellow") henon_map(-5, 5, -5, 5, 0.2, 0.5);
color("skyblue") translate([0, 0, 0.2]) cube([10,10,0.4], center=true );
color("black") 
    translate([0.8, -4.1, 0.3]) 
        linear_extrude(height = 0.375, center = true)
            text(size=0.8, "Henon Map", font="Karumbi");