IN = 25.4;
MM = 1;

function R (diameter) = diameter / 2.0;

function IN2MM(in) = in * IN;

function MM2IN(mm) = mm / IN;

module hex (diag = 10, h = 1) {
  cylinder(r = diag / 2, h = h, center = true, $fn = 6);
}

module tube(o = 1, i = 0, h = 1, center = false, $fn = 12) {
  $fn = $fn;
  union () {
    difference () {
      cylinder(r = o, h = h, center = center);
      cylinder(r = i,  h = h, center = center);
    }
  }
}

module m3_nut (H = 5) {
  cylinder(r=R(6.6), h=H, center=true, $fn=6);
}
module m4_nut (H = 3.1) {
  cylinder(r = R(8.1), h = H, center = true, $fn = 6);
}

module rounded_cube (cube_arr = [1, 1, 1], d = 0, center = false) {
  off_x = 0;
  off_y = 0;
  r = d/2;
  union () {
    cube([cube_arr[0] - d, cube_arr[1], cube_arr[2]], center = center);
    cube([cube_arr[0], cube_arr[1] - d, cube_arr[2]], center = center);
    translate ([1 * (cube_arr[0] / 2) - r , 1 * (cube_arr[1] / 2)- r, 0]) cylinder(r = r, h = cube_arr[2], center = center);
    translate ([-1 * (cube_arr[0] / 2) + r, -1 * (cube_arr[1] / 2) + r, 0]) cylinder(r = r, h = cube_arr[2], center = center);
    translate ([1 * (cube_arr[0] / 2) - r, -1 * (cube_arr[1] / 2) + r, 0]) cylinder(r = r, h = cube_arr[2], center = center);
    translate ([-1 * (cube_arr[0] / 2) + r, 1 * (cube_arr[1] / 2)- r, 0]) cylinder(r = r, h = cube_arr[2], center = center);
  }
}

module c_battery () {
  /* C Cell battery, 26.1 × 50 */
  x = 26.1;
  x_fuzz = .3;
  y = 50;
  y_fuzz = 2;
  cylinder(r = (x + x_fuzz) / 2, h = y + y_fuzz, center = true);
}

module sub_c_battery () {
  /* Sub C Cell battery, 22.2 × 42.9 */
  x = 22.2;
  x_fuzz = .3;
  y = 42.9;
  y_fuzz = 2;
  cylinder(r = (x + x_fuzz) / 2, h = y + y_fuzz, center = true);
}

module cone_45 (d = 1, center = false) {
  cylinder(r1 = d/2, r2 = 0, h = d, center = center);
}

module decoys (d = 10, z = 0, number = 4, cube_size = 4, debug = false) {
  for (i = [0: number]) {
    rotate([0, 0, (360/number) * i]) translate([d, 0, z]) cube([cube_size, cube_size, cube_size], center = true);
    if (debug && i == 0) {
      rotate([0, 0, (360/number) * i]) translate([d, 0, z]) cube([cube_size * 5, cube_size* 5, cube_size], center = true);
    }
  }
}

//////////////////////////////////////////////////////////////////////////////////////////////
// Paraboloid module for OpenScad
//
// Copyright (C) 2013  Lochner, Juergen
// http://www.thingiverse.com/Ablapo/designs
//
// This program is free software. It is 
// licensed under the Attribution - Creative Commons license.
// http://creativecommons.org/licenses/by/3.0/
//////////////////////////////////////////////////////////////////////////////////////////////

module paraboloid (y=10, f=5, rfa=0, fc=1, detail=44){
  // y = height of paraboloid
  // f = focus distance 
  // fc : 1 = center paraboloid in focus point(x=0, y=f); 0 = center paraboloid on top (x=0, y=0)
  // rfa = radius of the focus area : 0 = point focus
  // detail = $fn of cone

  hi = (y+2*f)/sqrt(2); // height and radius of the cone -> alpha = 45° -> sin(45°)=1/sqrt(2)
  x =2*f*sqrt(y/f); // x  = half size of parabola
  
  translate([0,0,-f*fc]) // center on focus 
  rotate_extrude(convexity = 10,$fn=detail ) // extrude paraboild
  translate([rfa,0,0]) // translate for fokus area   
  difference(){
    union(){ // adding square for focal area
      projection(cut = true) // reduce from 3D cone to 2D parabola
        translate([0,0,f*2]) rotate([45,0,0]) // rotate cone 45° and translate for cutting
        translate([0,0,-hi/2])cylinder(h= hi, r1=hi, r2=0, center=true, $fn=detail); // center cone on tip
      translate([-(rfa+x ),0]) square ([rfa+x , y ]); // focal area square
    }
    translate([-(2*rfa+x ), -1/2]) square ([rfa+x ,y +1] );           // cut of half at rotation center 
  }
}

/*
//  Height of trapazoid
height = 19;

//  Width of top cube
top_x = 30;
//  Length of top cube
top_y = 34;

//  Width of bottom cube
bottom_x = 45;
//  Length of bottom cube
bottom_y = 65;

wall_thickness = 2;
*/
module trap_cube(height = 19, top_x = 30, top_y = 34, bottom_x = 45, bottom_y = 65, wall_thickness = 2) {
  difference(){
    hull(){
      translate([0,0,height])
        cube([top_x, top_y, 0.1], center=true);
        cube([bottom_x, bottom_y, 0.1], center=true);
      }

    hull(){
      translate([0,0,height])
        cube([top_x - wall_thickness, top_y - wall_thickness, 0.1], center=true);
        cube([bottom_x - wall_thickness, bottom_y - wall_thickness, 0.1], center=true);
    }
  }
}

// switch module
module optoswitch() {
    difference(){
        union (){
            color("gray") cube([24.5,3.5,6.4]);
            color("gray")translate([6.63,0,0]) cube([4.45,11.3,6.3]);
            color("gray")translate([13.63,0,0]) cube([4.45,11.3,6.3]);
        }
        for ( hole = [2.75,24.5-2.75] ){
           rotate([90,0,0]) translate([hole,6.4/2,-4]) cylinder(r=1.5, h=4.5,$fn=40);
        }    
    }
}

module opto_endstop () {
  difference(){
    union(){
        // base PCB
        color("green") cube([33.0,1.6,10.5]);
        // add the switch module
        translate([8.4,1.6,10.5/2-6.4/2]) optoswitch();
        // connector
        translate([0.2,-7,0]) color("white") cube([5.8,7,10.5]);
        // led
        translate([3.5,1.6,10.5/2-1.5/2]) color("red") cube([2,0.7,1.5]);
    }
    translate([8.4,0,10.5/2-6.4/2]) {
      for ( hole = [2.75,24.5-2.75] ){
        rotate([90,0,0]) translate([hole,6.4/2,-4]) cylinder(r=1.5, h=4.5,$fn=40);
      }
    }
  }
}