module Tetrahedon(side=5) {
    h = (side/4)*sqrt(6);
    linear_extrude(height=h,scale=0)
      translate([-side/2,-(sqrt(3)/6)*side,0])
      polygon([
          [0,0],
          [side,0],
          [side/2,sqrt(pow(side,2)-pow(side/2,2))],
          [0,0]
      ]);
}

module Icosahedron_side(side=5){
    translate([side/2,(sqrt(3)/6)*side,0])
        difference(){
            Tetrahedon(side);
            translate([0,0,side/2])
                cube([side+1,side+1,side-2],center=true);
        }
}

module Icosahedron(side=5) {
    translate([-2.75*side,-sqrt(pow(side,2)-pow(side/2,2))/2,0])
        union(){
            for(a=[0:4]){    
                translate([a*side,0,0])
                    Icosahedron_side(side);
                
                translate([a*side+3/2*side,sqrt(pow(side,2)-pow(side/2,2)),0])
                    rotate([0,0,180])
                        Icosahedron_side(side);
                
                translate([a*side+1/2*side,sqrt(pow(side,2)-pow(side/2,2)),0])
                    Icosahedron_side(side);
                
                translate([(1+a)*side,0,0])
                    rotate([0,0,180])
                        Icosahedron_side(side);
            }
        }
}

module Icosahedron_map(side=10){
    textsize=(sqrt(3)/6)*side;
    textdepth=.3;
    fontstring="Liberation Sans";
    xoff=1/4*(sqrt(3)*side - side);
    difference(){
        Icosahedron(side);
        translate([-2.25*side,-xoff,.3])
            rotate([180,0,180])
                linear_extrude(height=.3)
                    text(text="1",size=textsize,font=fontstring,halign="center",valign="center");
        translate([.75*side,-xoff,textdepth])
            rotate([180,0,180])
                linear_extrude(height=textdepth)
                    text(text="2",size=textsize,font=fontstring,halign="center",valign="center");
        translate([-1.75*side,2/3*side,textdepth])
            rotate([180,0,180])
                linear_extrude(height=textdepth)
                    text(text="3",size=textsize,font=fontstring,halign="center",valign="center");
        translate([-.25*side,-2/3*side,textdepth])
            rotate([180,0,0])
                linear_extrude(height=textdepth)
                    text(text="4",size=textsize,font=fontstring,halign="center",valign="center");
        translate([1.75*side,-2/3*side,textdepth])
            rotate([180,0,0])
                linear_extrude(height=textdepth)
                    text(text="5",size=textsize,font=fontstring,halign="center",valign="center");
        translate([-.75*side,xoff,textdepth])
            rotate([180,0,0])
                linear_extrude(height=textdepth)
                    text(text="6",size=textsize,font=fontstring,halign="center",valign="center");
        translate([-.75*side,1.75*xoff,textdepth])
            rotate([180,0,0])
                linear_extrude(height=textdepth)
                    text(text="_",size=textsize,font=fontstring,halign="center",valign="center");
        translate([2.25*side,xoff,textdepth])
            rotate([180,0,0])
                linear_extrude(height=textdepth)
                    text(text="7",size=textsize,font=fontstring,halign="center",valign="center");
        translate([.25*side,2/3*side,textdepth])
            rotate([180,0,180])
                linear_extrude(height=textdepth)
                    text(text="8",size=textsize,font=fontstring,halign="center",valign="center");
        translate([-1.25*side,-xoff,textdepth])
            rotate([180,0,180])
                linear_extrude(height=textdepth)
                    text(text="9",size=textsize,font=fontstring,halign="center",valign="center");
        translate([-1.25*side,-1.75*xoff,textdepth])
            rotate([180,0,180])
                linear_extrude(height=textdepth)
                    text(text="_",size=textsize,font=fontstring,halign="center",valign="center");
        translate([1.25*side,2/3*side,textdepth])
            rotate([180,0,180])
                linear_extrude(height=textdepth)
                    text(text="10",size=textsize,font=fontstring,halign="center",valign="center");
        translate([-1.25*side,-2/3*side,textdepth])
            rotate([180,0,0])
                linear_extrude(height=textdepth)
                    text(text="11",size=textsize,font=fontstring,halign="center",valign="center");
        translate([1.25*side,xoff,textdepth])
            rotate([180,0,0])
                linear_extrude(height=textdepth)
                    text(text="12",size=textsize,font=fontstring,halign="center",valign="center");
        translate([-2.25*side,-2/3*side,textdepth])
            rotate([180,0,0])
                linear_extrude(height=textdepth)
                    text(text="13",size=textsize,font=fontstring,halign="center",valign="center");
        translate([-.25*side,-xoff,textdepth])
            rotate([180,0,180])
                linear_extrude(height=textdepth)
                    text(text="14",size=textsize,font=fontstring,halign="center",valign="center");
        translate([1.75*side,-xoff,textdepth])
            rotate([180,0,180])
                linear_extrude(height=textdepth)
                    text(text="15",size=textsize,font=fontstring,halign="center",valign="center");
        translate([-.75*side,2/3*side,textdepth])
            rotate([180,0,180])
                linear_extrude(height=textdepth)
                    text(text="16",size=textsize,font=fontstring,halign="center",valign="center");
        translate([2.25*side,2/3*side,textdepth])
            rotate([180,0,180])
                linear_extrude(height=textdepth)
                    text(text="17",size=textsize,font=fontstring,halign="center",valign="center");
        translate([.75*side,-2/3*side,textdepth])
            rotate([180,0,0])
                linear_extrude(height=textdepth)
                    text(text="18",size=textsize,font=fontstring,halign="center",valign="center");//*/
        translate([-1.75*side,xoff,textdepth])
            rotate([180,0,0])
                linear_extrude(height=textdepth)
                    text(text="19",size=textsize,font=fontstring,halign="center",valign="center");
        translate([.25*side,xoff,textdepth])
            rotate([180,0,0])
                linear_extrude(height=textdepth)
                    text(text="20",size=textsize,font=fontstring,halign="center",valign="center");//*/
    }
}

Icosahedron_map(side=10);