[User]
I'd like to design a parametric cup holder that can also be used for bottles, and I want it to be customizable. I'm thinking something similar to the design I saw on Thingiverse (thing:2812261).

Here are the parameters I'm thinking of:

**General:**

*   **`purpose`**:  A string that can be "Cup", "Tumbler", or "Bottle", which will change the inner cylinder.
*   **`part`**: A string that determines what to generate: "All", "Cup Holder Only", "Latch Only", or "Text Only".
*   **`holder_thickness`**: The thickness of the cup holder walls.
*   **`total_height`**: Overall height.
*   **`height_1`**: Height of the main cylindrical part of the cup holder.
*   **`height_2`**: Height of the bottom part of the cylinder.
*   **`height_bottom_lid`**:  Height of the bottom lid, used only when `purpose` is "Bottle".

**Cup/Cylinder Dimensions**
*   **`diameter_1`**:  The diameter at the top of the cylinder.
*   **`diameter_2`**: The inner diameter of the main cylinder.
*   **`diameter_3`**:  Diameter of the inner bottom cylinder
*   **`diameter_4`**: Diameter of the outer bottom cylinder

**Latch/Handle:**

*   **`handle_width`**:  Width of the handle.
*   **`handle_thickness`**: Thickness of the handle.
*   **`handle_distance`**: Distance the handle protrudes from the cup holder.
*   **`tamTrava`**: Length of latch segments
*  **`tamanhoqY`**:  Height of latch segments
*   **`offsetDimLT`**: Offset for the latch squares.
*   **`internal_separation_thickness`**: Clearance for the latch.
*    **`latch_edge_thickness`**: Thickness of the latch's edge.
*   **`latch_clearance`**: Clearance for the latch mechanism
* **`scale_factor`** (Calculated): Folga do encaixe.

**Text (Optional):**
*   **`text`**: String to be written. If empty, no text will be written.
*   **`type_of_font`**: String: font name for the text ("knewave.dxf", "BlackRose.dxf", "orbitron.dxf", "Letters.dxf", "braille.dxf")
*   **`letter_height`**: Height of the text letters.
*   **`letter_thickness`**: Extrude of the text letters.
*    **`text_bold`**: Integer to set text bold level
*    **`up_text`**: Integer to translate text up from the face
*    **`down_text`**: Integer to translate text down from the face

**Fillet:**
*  **`fillet`**: Radius of fillets to round the edges of the handle/latch box

I need to use the `Write.scad` library to render the text.

Could you please generate the OpenSCAD files for this design?

[Assistant]
CupHolderGeneratorV19.scad:
```
// Customizable Cup Holder Generator( Parametric)
// by Joao Laurindo, March 2018
// https://www.thingiverse.com/thing:2812261
// Customizable Cup Holder Generator( Parametric) is licenced under Creative Commons :
// Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)
// http://creativecommons.org/licenses/by-nc-sa/4.0/

// Local library
//use<Write.scad>

//For Thingiverse
use <write/Write.scad>
// preview[view:north west, tilt:top diagonal]

$fa=1*1;// 1 while design
$fs=1.5*1;//1.5 while design
//or
//$fn = 50*1;//50 while design

//variaveis globais

//made to hold:
purpose = "Cup"; //[first:Cup,second:Tumbler,both:Bottle]

//Part to Print:
part = "all";//[all:All,cHolder_only:Cup Holder Only,latch_only:Latch Only,text_only:Text Only]

//Cup
holder_thickness = 5;//[3:0.5:50]
diameter_1 = 80;
radius_1 = diameter_1/2;
diameter_2 = 75;
radius_2 = diameter_2/2;
diameter_3 = 40;
radius_3 = diameter_3/2;
diameter_4 = 40;
radius_4 = diameter_4/2;

height_1 = 110;//[5:250]

height_2 = 5;//[5:250]
total_height = height_1 + height_2;

//If you selected Bottle
height_bottom_lid = 5;//[3:0.5:20]

//Trava Transversal
delta = 0.0001*1; // para efeito de cortes e estabilidade sistema, multiplicado por 1 para nao aparecer no customizer

// I suggest larger than 10mm
handle_width = 30;//[5:0.5:100]

handle_thickness = 6;// [5:0.5:30]
handle_distance = 10;//// [10:0.5:100]

tamTrava = 2*1;
tamanhoqY = 6*1; // minimo 5mm para descontar 2*offsetDimLT e ser>0.
offsetDimLT = 2*1;
internal_separation_thickness = 2*1;// clearence da garra
latch_edge_thickness = 10;//[10:0.5:30]

//latch Clearance
latch_clearance = 0.3;//[0.2:0.05:0.4]
scale_factor = (2*(tamTrava+2*offsetDimLT+internal_separation_thickness)+handle_thickness+2*latch_clearance) / (2*(tamTrava+2*offsetDimLT+internal_separation_thickness)+handle_thickness);// calculo da folga

//Holder e Trava
fillet = latch_edge_thickness/2;// para boxHolder, pode travar tb em 4mm por exemplo
espessuraXholder = handle_distance+handle_thickness;
espessuraYholder = handle_width+latch_edge_thickness;

/* [Add Text] */
//If you want, put some text here:
text= "Text Here";
type_of_font="knewave.dxf";//[knewave.dxf:Knewave,BlackRose.dxf:Black Rose,orbitron.dxf:Orbitron,Letters.dxf:Letters,braille.dxf:Braille]
//The height(size) of the letters in mm
letter_height = 4;
// The extrude of the letters in mm
letter_thickness = 1;
text_bold=1;//
up_text = 0;//[0:0.5:100]
down_text = 0;//[0:0.5:100]

//-------------------------------------------------------------//
//inicia os trabalhos ;-)
//cupHolder(radius_4,radius_3,radius_2,radius_1,holder_thickness,handle_distance,total_height);

if (part =="all"){
    cupHolder(radius_4,radius_3,radius_2,radius_1,holder_thickness,handle_distance,total_height);
         // quando part == "latch_only"
     translate([-(radius_1+holder_thickness+25),0,total_height])
     rotate([0,180,0])
     latchOnly(handle_thickness,total_height,true);

    }

else if (part == "cHolder_only"){

cupHolder(radius_4,radius_3,radius_2,radius_1,holder_thickness,handle_distance,total_height);
        }

else if (part == "text_only"){

        textOnly();

    }

 else{
     // quando part == "latch_only"
     translate([0,0,total_height])
     rotate([0,180,0])
     latchOnly(handle_thickness,total_height,true);

     }

module latchCentered(handle_thickness,AlturaPortaCopo,trava){

    deslocX =(tamTrava+2*offsetDimLT+internal_separation_thickness+handle_thickness/2+2*fillet)+(radius_1+holder_thickness-2*fillet);
    deslocY = (latch_edge_thickness+tamanhoqY/2)-(latch_edge_thickness+tamanhoqY+handle_width+2*fillet)/2;

    translate([deslocX,deslocY,0]) latch(handle_thickness,AlturaPortaCopo,trava);

    }

module cupHolder(radius_4,radius_3,radius_2,radius_1,espessuraCil,distAlca,total_height){

offsetDim = 4;

raioExterno = espessuraCil + radius_1;

  union(){
     if(text!="Text Here"){

        textOnly();
    }
    difference(){
        difference(){
            union(){
                echo("scale_factor is =",scale_factor);
                scale([scale_factor,scale_factor,1]){// folga do encaixe;
                latchCentered(handle_thickness,total_height,false);
                }
                cylinder(h=total_height,r1=raioExterno,r2=raioExterno);//cilindro externo
                    }

        translate([0,0,height_2])
         if (purpose == "Cup") {
            radius_3 = radius_2;
            radius_4 = radius_2;
            cylinder(h=total_height+delta - height_2,r1=radius_2,r2=radius_1);// cilindro interno para subtrair
        } else if (purpose == "Bottle") {
            radius_2 = radius_1;
            radius_3 = radius_1;
            radius_4 = radius_1;
            cylinder(h=total_height+delta - height_2,r1=radius_2,r2=radius_1);// cilindro interno para subtrair
        }
            else{
              cylinder(h=total_height+delta - height_2,r1=radius_2,r2=radius_1);// cilindro interno para subtrair
              }

                    }

        if (purpose == "Cup") {
            radius_3 = radius_2;
            radius_4 = radius_2;
            cylinder(h=height_2+delta,r1=radius_4,r2=radius_3); //cilindro tampo de baixo
        } else if (purpose == "Bottle") {
            radius_2 = radius_1;
            radius_3 = radius_1;
            radius_4 = radius_1;
            cylinder(h=height_2+delta,r1=radius_4,r2=radius_3); //cilindro tampo de baixo
        } else{
               cylinder(h=height_2+delta,r1=radius_4,r2=radius_3); //cilindro tampo de baixo
        }
                }

       if (purpose == "Bottle") {

           difference(){
               cylinder(h=height_bottom_lid+delta,r1=raioExterno,r2=raioExterno); //cilindro tampo de baixo
               cylinder(h=height_bottom_lid+2*delta,r1=raioExterno/5,r2=raioExterno/5); //cilindro tampo de baixo

               }

       }

    }

}

module boxHolder(X,Y,qY,distanciaBordaTrava,handle_distance,fillet){

boxHolderX = X+handle_distance;
boxHolderY = Y;

  translate([-(boxHolderX+2*fillet)/2+handle_thickness/2+handle_distance,(Y/2+fillet)-(distanciaBordaTrava+qY/2),0])
  linear_extrude(height = total_height)
  offset(r = fillet) {
            square([boxHolderX,boxHolderY],center=true);
                     }
}

module latch(handle_thickness,AlturaPortaCopo,trava){

larguraX = 2*(tamTrava+2*offsetDimLT+internal_separation_thickness)+handle_thickness;
larguraY = latch_edge_thickness+tamanhoqY+handle_width;

difference(){
    // chama modulo para box
    boxHolder(larguraX,larguraY,tamanhoqY,latch_edge_thickness,handle_distance,fillet);

        union(){
            difference(){
                linear_extrude(height = AlturaPortaCopo){
                offset(r = offsetDimLT) {

                    union(){
                        square([larguraX-2*offsetDimLT,tamanhoqY-2*offsetDimLT],center=true);

                        translate([(larguraX)/2 - (tamTrava/2+offsetDimLT),0,0])
                        square([tamTrava,tamanhoqY+2*tamTrava], center = true);

                        translate([-(larguraX)/2 +(tamTrava/2+offsetDimLT),0,0])
                        square([tamTrava,tamanhoqY+2*tamTrava], center = true);
                           }
                                        }
                                                        }

                        linear_extrude(height = AlturaPortaCopo/10){
                            offset(r = offsetDimLT) {
                            union(){
                                square([larguraX-2*offsetDimLT,tamanhoqY-2*offsetDimLT],center=true);

                                translate([(larguraX)/2 - (tamTrava/2+offsetDimLT),0,0])
                                square([tamTrava,tamanhoqY+2*tamTrava], center = true);

                                translate([-(larguraX)/2 +(tamTrava/2+offsetDimLT),0,0])
                                square([tamTrava,tamanhoqY+2*tamTrava], center = true);
                                   }
                                                    }
                                                   }

                        }

            if(!trava){
                // Para tamanho Alca
                    linear_extrude(height = AlturaPortaCopo){
                        offset(r = offsetDimLT) {
                        translate([0,+(handle_width+offsetDimLT)/2,0])
                        square([handle_thickness-2*offsetDimLT,handle_width],center=true);
                                                }
                                                            }
                       }

                       //Para tamanho Borda
                    linear_extrude(height = AlturaPortaCopo){
                        translate([0,-(latch_edge_thickness+tamanhoqY)/2+tamanhoqY/2,0])
                        square([handle_thickness,latch_edge_thickness+tamanhoqY],center=true);

                                                            }

                }
             }

}

module textOnly(){
                color("red")
            writecylinder(text,[0,0,0],holder_thickness+radius_1,total_height,face="front", font=type_of_font,t=letter_thickness,h=letter_height,bold=text_bold,west=90,up=up_text,down=down_text);

    }

//apenas o latch
module latchOnly(handle_thickness,AlturaPortaCopo,trava){

larguraX = 2*(tamTrava+2*offsetDimLT+internal_separation_thickness)+handle_thickness;
larguraY = latch_edge_thickness+tamanhoqY+handle_width;

union(){
            difference(){
                linear_extrude(height = AlturaPortaCopo){
                offset(r = offsetDimLT) {

                    union(){
                        square([larguraX-2*offsetDimLT,tamanhoqY-2*offsetDimLT],center=true);

                        translate([(larguraX)/2 - (tamTrava/2+offsetDimLT),0,0])
                        square([tamTrava,tamanhoqY+2*tamTrava], center = true);

                        translate([-(larguraX)/2 +(tamTrava/2+offsetDimLT),0,0])
                        square([tamTrava,tamanhoqY+2*tamTrava], center = true);
                           }
                                        }
                                                        }

                        linear_extrude(height = AlturaPortaCopo/10){
                            offset(r = offsetDimLT) {
                            union(){
                                square([larguraX-2*offsetDimLT,tamanhoqY-2*offsetDimLT],center=true);

                                translate([(larguraX)/2 - (tamTrava/2+offsetDimLT),0,0])
                                square([tamTrava,tamanhoqY+2*tamTrava], center = true);

                                translate([-(larguraX)/2 +(tamTrava/2+offsetDimLT),0,0])
                                square([tamTrava,tamanhoqY+2*tamTrava], center = true);
                                   }
                                                    }
                                                   }

                        }

            if(!trava){
                // Para tamanho Alca
                    linear_extrude(height = AlturaPortaCopo){
                        offset(r = offsetDimLT) {
                        translate([0,+(handle_width+offsetDimLT)/2,0])
                        square([handle_thickness-2*offsetDimLT,handle_width],center=true);
                                                }
                                                            }
                       }

                       //Para tamanho Borda
                    linear_extrude(height = AlturaPortaCopo){
                        translate([0,-(latch_edge_thickness+tamanhoqY)/2+tamanhoqY/2,0])
                        square([handle_thickness,latch_edge_thickness+tamanhoqY],center=true);

                                                            }

                }
            }

```


[User]
I'd like to create a customizable disk with a hole in the middle, if I want it. The user should be able to control the diameter and height of the disk, and how many segments make up its circumference. I'd also like to have a toggle for whether or not there's a hole, and if there is a hole, it should have a diameter that's half the diameter of the disk, and its height should be twice the height of the disk.

It should be customizable through the OpenSCAD customizer, so users can change these parameters easily. I've provided an example file, named `CustomizerExample.scad`, which includes all the functionality that I want to incorporate into the design, except, I want to have an option for the number of segments for the hole which would default to be half the number of segments in the outer surface, but a minimum of three segments, so it's not too blocky. Could you write the `.scad` files I'll need? Also, no libraries are required.

[Assistant]
CustomizerExample.scad:
```
/* Simple Customizer example.
 * See http://customizer.makerbot.com/docs for more info on making a customizer-compatible SCAD file.
 * See https://www.thingiverse.com/thing:2812634 for instructions on using customizer inside the latest OpenSCAD builds. */

// Diameter of the disk
diameter = 20;

// Height of the disk
height = 10;

// Segments in the outer surface
segments = 64; //[3:128]

// Make a hole in the middle?
hole = "yes"; //[yes,no]

/* [Hidden] */
r = diameter / 2;
segments2 = segments > 6 ? round(segments/2) : 3;
// Boolean options work in the OpenSCAD customizer: they will show up as a checkbox. They don't work in the Thingiverse customizer however at the time of this writing. Therefore either compare with "yes" every time, or convert the value to a boolean for cleaner code:
bHole = (hole == "yes");

difference() {
    cylinder(r=r, height, $fn=segments);

    if(bHole) {
        translate([0, 0, -height/2]) cylinder(r=r/2, height*2, $fn=segments2);
    }
}

```


[User]
Hey, I'm looking to get a parametric OpenSCAD design for a blind bracket. I've tried using the customizer for one I found online, but it's throwing errors related to shared libraries and I'd rather not mess with that. Plus, I want to customize it a bit anyway.

The general idea is a bracket that mounts to a wall and then has a pin that goes into the blind mechanism. I'm thinking of something like a small shelf bracket with a pin sticking out perpendicular to the 'shelf' portion, and then a truss connecting the 'shelf' portion and the pin for added strength.

Here are some key parameters I'd like to control:

*   **Bracket Length (L):** The length of the shelf part of the bracket.
*   **Material Thickness (thk):** The thickness of the bracket material itself.
*   **Pin Distance (pd):** The distance the pin is located from the wall-mounted face of the bracket.
*   **Pin Diameter (dia):** The diameter of the cylinder that supports the pin. I'd prefer this to be <= the length of the shelf portion of the bracket.
*   **Bracket Width (W):** The width of the shelf part of the bracket, not including the thickness of the bracket itself.
*   **Hole Offset (H_O):** The offset of the mounting holes from the outer edge of the bracket.
*   **Hole Diameter (H_D):** The diameter of the mounting holes.
*   **Hole Center-Center (H_CC):** The center-to-center distance of the mounting holes.
*   **Pin Thickness (p_thk):** The length of the pin.
*  **Pin Diameter (p_dia):** The diameter of the pin.
*  **Truss Thickness (t_thk):** The thickness of the triangular support truss.
*   **Fillet Radius (fr):** The radius of the fillets on the base of the bracket.

I'm not too fussy about it all being in one SCAD file. If it's easier to have different modules or files for different parts, that's fine too. Could you also make sure to include `$fn` as a variable for cylinder resolution and a `DELTA` variable for small offsets to make sure cutouts work well? I also want the fillet to be a proper minkowski fillet so I don't have a bunch of flat sides. I don't need any included libraries beyond basic functionality. Thanks!

[Assistant]
blinds_bracket.scad:
```
//************************************************************************************
//*
//*  This creates a bracket for blinds
//*
//* The global variables can be edited as required for better resolution, a tighter
//*  or looser fit or a different fillet size.
//*
//* Keith Welker 2/2/18
//************************************************************************************
//dimensions (all in mm) (unless stated otherwise)

//
// MISC variables
//
//$fn for cylinders
FN = 360;// [60:Low Detail,120:Medium Detail,360:High Detail]

//a small offset to clear up any cutouts.
DELTA = .005; // [.001,.005,.01,.1]

//
// bracket configuration variables
//
//length of the bracket
L = 22; // [15:35]
// material thickness
thk = 3; //[2:0.5:6]
//pin distance from base
pd = 27.5; // [20:40]
//diamater at top of bracket (must be <= length)
dia = 16; // [15:35]
// bracket foot width (not including the thickness of the bracket)
W = 12; //[6:18]
//hole offset from upper bracket
H_O = 7; //[4:12]
//hole diameter
H_D = 4; //[1:6]
//hole center-center
H_CC = 11; //[5:14]
//pin thickness
p_thk = 5; //[1:8]
//pin diameter
p_dia = 2.75; //[1:5]

//truss thickness
t_thk = 6; //[2:10]

//fillet radius
fr = 3; //[2:8]

union()
{
    //truss
    t_points= [[0,0], [0,t_thk], [pd,0]];
    rotate([270,270,0])
    translate([thk,W+thk-DELTA,(L/2)-thk/2])
    linear_extrude(height = thk)
    polygon(t_points);

    // add the pin
    rotate([0,90,0])
    translate([-(thk+pd),L/2,W-p_thk])
    cylinder($fn=FN, h = p_thk, d = p_dia);

    //pin mounting flange
    p_points= [[0,0], [(L-dia)/2,pd], [L-(L-dia)/2, pd], [L,0]];
    rotate([90,0,0])
    rotate([0,90,0])
    translate([0,thk,W])
    linear_extrude(height = thk)
    polygon(p_points);
    rotate([0,90,0])
    translate([-(thk+pd),L/2,W])
    cylinder($fn=FN, h = thk, d = dia);

    //the base with mounting holes
    difference()
    {
        translate([fr/2,fr/2,0])
        //cube([W+thk+t_thk,L,thk]);
        base([W+thk+t_thk,L,thk], fr);
        translate([W-H_O,L-H_CC/2,-DELTA])
        cylinder($fn=FN, h = thk+2*DELTA, d = H_D);
        translate([W-H_O,H_CC/2,-DELTA])
        cylinder($fn=FN, h = thk+2*DELTA, d = H_D);
    }

}

    module base(size, fr)
    {
        x = size[0];
        y = size[1];
        z = size[2];
        minkowski()
        {
            cylinder($fn=FN, h = z/2, d= fr);
            cube([x-fr,y-fr,z/2]);
        }
    }

```


[User]
I'm looking to create a set of parametric twist-off lids for jars, and I'd like an OpenSCAD design that can handle a few specific features.

First, the core of the design should be a twist-off lid. I need to be able to set the inner diameter and height of the lid as parameters. I also need to control the wall thickness of the main body.

The design also needs the twist-off lugs. I'd like to be able to specify the number of lugs, the width, and the thickness (or height) of each lug.  It'd also be nice to have a parameter for adding a chamfer to the top of each lug, and the size of that chamfer should be controlled.

Beyond the basic lid, I'd also like two optional features. One is a coin slot. I need to be able to enable this slot via a parameter, and then set the length and width of the coin slot when it is enabled. The other is a hole pattern for things like salt shakers, etc. This should also be controlled via a parameter, and then the diameter of each hole, as well as the number of concentric rings of holes should be definable.

I'd like the design to use a variable called `$fn` to control the number of fragments when rendering, and also I need a small overlap between the lid and lug in order to create a manifold mesh. Can you also make sure that OpenSCAD doesn't crash due to rendering issues like this?

I'm not particularly attached to any specific library so I'd be okay with whatever you choose or no library if not necessary.

[Assistant]
twist-off-generator.scad:
```
// twist-off-cap generator or as we say in german:
// Nockendrehverschlussgenerator

// inner diameter of the lid
diameter = 41; // [10.0:100.0]
// inner height of the lid
height = 8; // [1:20]

simple_lid = false;
wall_thickness = 4;

//  number of lugs
n = 4; // [3,4,6]
// lug width
lug_width = 1;
// lug thickness (height)
lug_thickness = 1;
// height of the chamfer (0 = off)
chamfer_size = 0.5;

// enables coin slot generation (e.g. for creating a savings box)
coin_slot = false;
coin_slot_length = 28;
coin_slot_width = 3.2;

// generate hole pattern (e.g. for a salt dispender)
hole_pattern = false;
// diameter of each hole of the pattern
hole_pattern_diameter = 1.5;
// number of concentric rings with holes to generate
hole_pattern_rings = 5;

// hidden
$fn = 1 * 64; // number of fragments
overlap = 1 * 0.5; // oversizing lug ring to get a manifold mesh (otherwise openScad will crash)

// cam polygon parameter
di = diameter - 2 * lug_width; // inner diameter
dp = di * tan(180/n) / sin(180/n); // outer polygon diameter
dc = diameter * tan(180/n) / sin(180/n); // chamfering polygon diameter

// scaling of imported stl mesh
sxy = diameter / 20; // (20mm diameter)
sz = height / 3; // (3mm height)

union() {
    // lug construction
    translate([0, 0, height-lug_thickness-chamfer_size-overlap])
    color([0.8, 0, 0])
    render() difference(){
        cylinder(d=diameter+overlap, h=lug_thickness+chamfer_size); // cylinder
        translate ([0, 0, chamfer_size]) cylinder(d=dp, h =lug_thickness, $fn=n); // n-sided polygon
        cylinder(d1=dc, d2=dp, h=chamfer_size, $fn=n); // chamfering
    }

    difference() {
        if (simple_lid) {
            // simple lid
            color([0.0, 0.6, 0.8])
            render() difference() {
                translate([0, 0, -wall_thickness])
                cylinder(d=diameter+wall_thickness, h=height+wall_thickness);
                cylinder(d=diameter, h=height);
            }
        } else {
            // load prefab jar lid model
            scale([sxy, sxy, sz])
            color([0.0, 0.6, 0.8])
            import("jar-lid_blank.stl", convexity=3);
        }
        // coin slot
        if (coin_slot) {
            translate([0, 0, -0.5*sz*wall_thickness])
            cube([coin_slot_length, coin_slot_width, sz*wall_thickness], center=true);
        }

        // hole pattern
        if (hole_pattern) {
            for (ring = [1:hole_pattern_rings]) {
                n = ring*ring + 1;
                r = 2* (ring-1) * hole_pattern_diameter;

                for (i = [1:n]) {
                    x = r * cos(i*360/n);
                    y = r * sin(i*360/n);

                    translate([x, y, -sz*wall_thickness])
                    cylinder(d=hole_pattern_diameter, h=sz*wall_thickness);
                }
            }
        }
    }
}

```


[User]
Hey, I'm looking to design some boxes for holding tokens for a board game called Small World. I've got a bunch of different token types and numbers, and I want boxes that can hold specific amounts, and also a lid that slides on. I've seen some designs online that are similar but I want to make it my own.

Essentially, the box needs to have a base, a body, a passthrough for the race banner "lid," and a top that keeps the banner from just sliding off. The base should have a slightly stepped profile - like different thicknesses of the same shape, going wider at the bottom. The body just needs to be a straight extrusion, and the banner passthrough should be a gap in the side, the same shape as the main body, but with a slight interior offset. The top needs to also have a stepped profile, but working the other direction - it needs to get narrower the higher it goes to hold the banner.

I'd like to make it so that I can specify the number of tokens, and the script will automatically adjust the height of the box. The tokens are 2mm tall each, and I want a "race" section on top of the token section that's an additional 2mm, and that passthrough for the race banner.

Here's the tricky part - the main shape of the box should be this kind of rounded triangle/trapezoid-ish shape, with two rounded ends and a flat side. It's kind of described in the code I'm sharing. The box needs to be parametric so that I can adjust the base width and depth (x and y), and I would like the script to be able to create the box with the passthrough on either the left or right side.

Also, all of the offset commands use this same shape. I think that can be done with an underlying module or function. I'm happy to use libraries if that makes it easier, but I don't know enough to specify which ones. I want to be able to easily make boxes with different token capacities, anywhere from 8 tokens all the way up to 24 tokens. This code also has some text in it, but I don't really need that, just the box part.

Here's the old code as a reference for the shape, hopefully you can understand it. I will also include the other files that are mentioned in the comment as a reference. This looks like it's using standard OpenSCAD primitives.

```
//esta tiene solo 3 capas de base

$fn=100;
grosor=2;   //mm de grosor del muro
fichas=8;  //total de tokens (supone 2mm altura)
            //!!!!!!!!!
            // que redondee al siguiente par
            // 16->16, 17->18, 18->18

// 8 tokens: Apariciones (7+1)

//10 tokens: Enanos (8+1) 9-^10
//           Clérigos (9+1)

//12 tokens: 12 races total
//14 tokens: 2
//16 tokens: 6 (incloent leperchauns i skags)
//18 tokens: 3 (inclou brujas de hielo)
//20 tokens: 2
//22 tokens: 2 (els dos son 20+1, el lider pot anar en diagonal i serien 20 tokens nomes)

raza=2;		//mm altura raza

module placa(abierto=false, x=86, y=45) {
	offset(delta=0.1) //apariciones: -0.9
                       //anterior: -1
	union(){
		difference(){
			union(){
				translate([y/5, y/5])
					circle(y/5);
				translate([y/2, y/2])
					circle(y/2);
				polygon([
					[0,y/5],
					[0,y/2],
					[y/2,y],
					[x,y],
					[x-6,0],
					[y/5,0]]);
			}
			translate([x*0.875,0])
				translate([y/2,y/2])
					circle(y/2);
		}
		if(abierto)
			translate([2*x/3,0,0])
                union(){
                    translate([y/5, y/5])
                        circle(y/5);
                    translate([y/2, y/2])
                        circle(y/2);
                    polygon([
                        [0,y/5],
                        [0,y/2],
                        [y/2,y],
                        [x,y],
                        [x-6,0],
                        [y/5,0]]);
                }
	}
}

translate([0,0,-0.25])
difference() {
    union() {

		//base: 4 capas * 0.25mm

//		translate([0, 0, 0])
//			linear_extrude(0.25)
//				offset(delta=-1)
//					placa();

		translate([0, 0, 0.25])
			linear_extrude(0.25)
				offset(delta=-0.75)
					placa();

		translate([0, 0, 0.5])
			linear_extrude(0.25)
				offset(delta=-0.5)
					placa();

		translate([0, 0, 0.75])
			linear_extrude(0.25)
				offset(delta=-0.25)
					placa();

		//curva: 4 capas * 0.25mm

		translate([0, 0, 1])
			linear_extrude(0.25)
				resta(0, -2);

		translate([0, 0, 1.25])
			linear_extrude(0.25)
				resta(0.25, -1.75);

		translate([0, 0, 1.5])
			linear_extrude(0.25)
				resta(0.5, -1.5);

		translate([0, 0, 1.75])
			linear_extrude(0.25)
				resta(0.75, -1.25);

		//cuerpo: fichas-1 mm

		translate([0, 0, 2])
			linear_extrude(fichas-1)
				resta(1, -1);

		//pasador: raza mm

		translate([0, 0, fichas+1])
			linear_extrude(raza)
				resta(1, 0, true);

		//tope: 3 capas * 0.25mm + 1 capa * 1mm

		translate([0, 0, fichas+raza+1])
			linear_extrude(0.25)
				resta(1, -0.25, true);

		translate([0, 0, fichas+raza+1.25])
			linear_extrude(0.25)
				resta(1, -0.5, 1);

		translate([0, 0, fichas+raza+1.5])
			linear_extrude(0.25)
				resta(1, -0.75, 1);

		translate([0, 0, fichas+raza+1.75])
			linear_extrude(1)
				resta(1, -1, 1);

	}

	//translate([60,-10,0])
		//cube(80);
//    translate([10,22,0.75])
//          linear_extrude(1)
//              text("APARICIONES", font="Vafthrudnir:style=Regular", size=6);
//        translate([25,10,0.75])
//            linear_extrude(1)
//                text("7 + 1", font="ManuskriptGotisch:style=Regular", size=10);

}

module resta(exterior, interior, abierto=false){
	difference(){
		offset(delta=exterior)
			placa();
		offset(delta=interior)
			placa(abierto);
	}
}
```

Also, here's the description from the website:
"Put your race tokens on the box, slide the race banner like a lid and done!
Includes left-facing for Spanish and French editions, and right-facing for German and English.
Several sizes, to contain from 8 to 20 tokens. Now you can put keep leader with their troops, troll with their lairs, and halflings with their holes!
There's also the .scad if you want to tinker with it, just don't judge my programming skills!

Also try out https://www.thingiverse.com/thing:2817800

Small list of race tokens (all races include leader except Sky Islanders):
Size 8 box: White Ladies
Size 10 box: Dwarves, Priestesses, Khans, Drow
Size 12 box: Ghouls, Humans, Orcs, Wizards, Scavengers, Slingmen, Flames, Kraken, Liches, Ogres, Shrooms, Elves, Giants, Tritons, Pygmies, Goblins, Gypsies, Shrubmen, Cultists, Gnomes, Will-o-wisps
Size 14 box: Storm Giants, Lizardmen, Mudmen, Shadow Mimes, Spiderines, Halflings, Ratmen, Drakons
Size 16 box: Barbarians, Amazons, Homunculi, Igors, Mummies, Leprechauns, Skags
Size 18 box: Pixies, Kobolds, Escargots, Scarecrows, Wendigos, Ice Witches
Size 20 box: Sorcerers, Fauns, Iron Dwarves, Skeletons, Trolls
Also, a size 20 for the lost tribes (size 24 with Sky Islands!), a size 14 for the necromancer's ghosts and a size 14 for underworld's monsters."

Let me know if you have questions.

[Assistant]
smallworld_3.scad:
```
//esta tiene solo 3 capas de base

$fn=100;
grosor=2;   //mm de grosor del muro
fichas=8;  //total de tokens (supone 2mm altura)
            //!!!!!!!!!
            // que redondee al siguiente par
            // 16->16, 17->18, 18->18

// 8 tokens: Apariciones (7+1)

//10 tokens: Enanos (8+1) 9-^10
//           Clérigos (9+1)

//12 tokens: 12 races total
//14 tokens: 2
//16 tokens: 6 (incloent leperchauns i skags)
//18 tokens: 3 (inclou brujas de hielo)
//20 tokens: 2
//22 tokens: 2 (els dos son 20+1, el lider pot anar en diagonal i serien 20 tokens nomes)

raza=2;		//mm altura raza

module placa(abierto=false, x=86, y=45) {
	offset(delta=0.1) //apariciones: -0.9
                       //anterior: -1
	union(){
		difference(){
			union(){
				translate([y/5, y/5])
					circle(y/5);
				translate([y/2, y/2])
					circle(y/2);
				polygon([
					[0,y/5],
					[0,y/2],
					[y/2,y],
					[x,y],
					[x-6,0],
					[y/5,0]]);
			}
			translate([x*0.875,0])
				translate([y/2,y/2])
					circle(y/2);
		}
		if(abierto)
			translate([2*x/3,0,0])
                union(){
                    translate([y/5, y/5])
                        circle(y/5);
                    translate([y/2, y/2])
                        circle(y/2);
                    polygon([
                        [0,y/5],
                        [0,y/2],
                        [y/2,y],
                        [x,y],
                        [x-6,0],
                        [y/5,0]]);
                }
	}
}

translate([0,0,-0.25])
difference() {
    union() {

		//base: 4 capas * 0.25mm

//		translate([0, 0, 0])
//			linear_extrude(0.25)
//				offset(delta=-1)
//					placa();

		translate([0, 0, 0.25])
			linear_extrude(0.25)
				offset(delta=-0.75)
					placa();

		translate([0, 0, 0.5])
			linear_extrude(0.25)
				offset(delta=-0.5)
					placa();

		translate([0, 0, 0.75])
			linear_extrude(0.25)
				offset(delta=-0.25)
					placa();

		//curva: 4 capas * 0.25mm

		translate([0, 0, 1])
			linear_extrude(0.25)
				resta(0, -2);

		translate([0, 0, 1.25])
			linear_extrude(0.25)
				resta(0.25, -1.75);

		translate([0, 0, 1.5])
			linear_extrude(0.25)
				resta(0.5, -1.5);

		translate([0, 0, 1.75])
			linear_extrude(0.25)
				resta(0.75, -1.25);

		//cuerpo: fichas-1 mm

		translate([0, 0, 2])
			linear_extrude(fichas-1)
				resta(1, -1);

		//pasador: raza mm

		translate([0, 0, fichas+1])
			linear_extrude(raza)
				resta(1, 0, true);

		//tope: 3 capas * 0.25mm + 1 capa * 1mm

		translate([0, 0, fichas+raza+1])
			linear_extrude(0.25)
				resta(1, -0.25, true);

		translate([0, 0, fichas+raza+1.25])
			linear_extrude(0.25)
				resta(1, -0.5, 1);

		translate([0, 0, fichas+raza+1.5])
			linear_extrude(0.25)
				resta(1, -0.75, 1);

		translate([0, 0, fichas+raza+1.75])
			linear_extrude(1)
				resta(1, -1, 1);

	}

	//translate([60,-10,0])
		//cube(80);
//    translate([10,22,0.75])
//          linear_extrude(1)
//              text("APARICIONES", font="Vafthrudnir:style=Regular", size=6);
//        translate([25,10,0.75])
//            linear_extrude(1)
//                text("7 + 1", font="ManuskriptGotisch:style=Regular", size=10);

}

module resta(exterior, interior, abierto=false){
	difference(){
		offset(delta=exterior)
			placa();
		offset(delta=interior)
			placa(abierto);
	}
}
```


[User]
Hi! I'm trying to make a customisable thing for 3D printing but the Thingiverse customizer isn't working for me, so I need some help. I have an example of the sort of thing I want, but I'm not good at programming OpenSCAD. I'd like you to generate an OpenSCAD file (or files if it's cleaner that way) that lets me define several different parameters to generate a 3D model.

Essentially, I want to be able to choose between making a cube or a cylinder, and then, depending on what I've chosen, I want to be able to tweak some other measurements.

If I select a cube, I don't want any customisations for it yet, a simple cube will do.

If I select a cylinder, I'd like to be able to set a height, a diameter and the number of sides it has.

There should also be some other custom parameters for a power supply (width and thickness in mm) a VESA mount (75 or 100 mm), and the thickness of a support board, all in mm. These parameters should be available regardless of whether I've picked a cube or a cylinder but do not affect the shape.

Finally, regardless of the chosen shape, I'd like a `text("CUSTOMIZER")` to appear near the main shape.

I think I need to use the `cube()`, `cylinder()` and `text()` functions, and I am fine if the AI uses MCAD or similar libraries, if that will be helpful. Thanks for your help!

[Assistant]
customizer_openscad.scad:
```
/* Exemple customizer
By jeff le 03/2018
*/

//-------------------Declaration des variables

/* [Basic] */
//Choose your part / Choisis ta pièce
_type = "cube"; //[cube,cylindre]

/* [POWER SUPPLY] */
//Width / Largeur (in mm)
_pw_width = 66; //[1:1:200]
//Thickness / Epaisseur (in mm)
_pw_thick = 37; //[1:1:50]

/* [VESA MOUNT] */
//Vesa type / Type Vesa
_vesa = 100; //[75,100]

/* [SUPPORT BOARD] */
//Thick board / Eplaisseur de planche
_board_thick = 18; //[1:1:50]

/* [hidden] */
_epaisseur = 3;
_largeur = 20;
_ajustement = 1;

//-------------------!Déclaration des variables

//*******************************************************************************
//-------------------Contruction de la forme

if(_type == "cube")
	{

	cube(size = [10,10,10], center = true);

	}
else if(_type == "cylindre")
	{
	cylinder(20,20,20,$fn=3);
	}

	translate([0,10,0])text("CUSTOMIZER");
//-------------------!Contruction de la forme

```


[User]
Hey, I'm looking to design a bead roller, and I found this cool design online that I want to use as a starting point. It's parametric, which is great, and it's based on the idea of cutting out semi-circular tracks into a block of material.  Basically, you'd roll a soft material like clay or putty across it, and the tracks help form it into a bead.

I'd like to have a parametric design in OpenSCAD, similar to the linked model.  I need to be able to specify the radii for six different bead sizes, the radius of the guide tracks on the edge, the spacing distance between the tracks, the overall length of the block, and the thickness of the block (or half-thickness, as in the example, that's fine too).  I also need to control the resolution of the circles that make up the tracks (like using $fn for the circle segments). It'd also be nice if the code was reasonably well-commented, so I can understand what everything's doing.

The model I'm working from has the following variables/parameters which should all be settable:

*   `holeRadius00` to `holeRadius05`: Radius of each of the six bead-forming tracks.
*   `guideTrackRadius`: Radius of the edge guide tracks.
*   `spacingDistance`: Distance between tracks.
*   `blockLength`: Length of the overall block.
*   `halfBlockThickness`: Half of the thickness of the block.
*   `$fn`: Number of segments for drawing circles.

The design should be made so the bead-forming tracks should be positioned such that there's a spacing distance between the edge, then a guide track, then more spacing, then bead track, spacing, guide, etc. It should calculate the x-positions of the bead tracks based on the defined spacing and radii. The whole block should be centered along its x axis (but only along x). The whole thing should also be mirrored on the x-axis as well.

Basically, I want to generate a solid block with semi-circular grooves milled out. I also need guide tracks on the edges as the original design did.

I don't have any pre-existing code to provide, so I'm relying on you to generate everything. I'm hoping to use this to generate a few different configurations of bead rollers, so good flexibility and easy-to-understand code are key. Please make sure you can control the block's thickness using halfBlockThickness. I don't want any parts with a different thickness.

[Assistant]
ParametricBeadRoller.scad:
```
// Designed by Brian McEvoy, 24HourEngineer
// 24hourengineer.com
// 24hourengineer@gmail.com

// Please note that the dimensions shown here are radii, not diameters
holeRadius00 = 6;
holeRadius01 = 8;
holeRadius02 = 10;
holeRadius03 = 10;
holeRadius04 = 8;
holeRadius05 = 6;

guideTrackRadius = 2;
spacingDistance = 2;
blockLength = 150;

// This thickness should be at least as large as the biggest hole radius plus a few millimeters
halfBlockThickness = 15;

// This is basically the resolution of the circles. High number = smooth circles
$fn = 30;

///// Play around with the red numbers above this line and
///// press F6 to see the results. Zero is an acceptable variable.

//2//4//H//o//u//r////E//n//g//i//n//e//e//r//
//2//4//H//o//u//r////E//n//g//i//n//e//e//r//

blockWidth = holeRadius00*2 + holeRadius01*2 + holeRadius02*2 + holeRadius03*2 + holeRadius04*2 + holeRadius05*2 + guideTrackRadius*4 + spacingDistance*10;
hole00Distance = (spacingDistance*2 + guideTrackRadius*2 + holeRadius00);
hole01Distance = (spacingDistance*3 + guideTrackRadius*2 + holeRadius00*2 + holeRadius01);
hole02Distance = (spacingDistance*5 + guideTrackRadius*2 + holeRadius00*2 + holeRadius01*2 + holeRadius02);
hole03Distance = (spacingDistance*6 + guideTrackRadius*2 + holeRadius00*2 + holeRadius01*2 + holeRadius02*2 + holeRadius03);
hole04Distance = (spacingDistance*7 + guideTrackRadius*2 + holeRadius00*2 + holeRadius01*2 + holeRadius02*2 + holeRadius03*2 + holeRadius04);
hole05Distance = (spacingDistance*8 + guideTrackRadius*2 + holeRadius00*2 + holeRadius01*2 + holeRadius02*2 + holeRadius03*2 + holeRadius04*2 + holeRadius05);

// Body
difference(){
    translate([blockWidth/2, -halfBlockThickness/2, 0]){
        cube([blockWidth, halfBlockThickness, blockLength], center = true);
    }
    // First bead rolling track
    translate([hole00Distance, 0, 0]){
        trackTemplate(holeRadius00);
    }
    // Second bead rolling track
    translate([hole01Distance, 0, 0]){
        trackTemplate(holeRadius01);
    }
    // Third bead rolling track
    translate([hole02Distance, 0, 0]){
        trackTemplate(holeRadius02);
    }
    // Fourth bead rolling track
    translate([hole03Distance, 0, 0]){
        trackTemplate(holeRadius02);
    }
    // Fifth bead rolling track
    translate([hole04Distance, 0, 0]){
        trackTemplate(holeRadius04);
    }
    // Sixth bead rolling track
    translate([hole05Distance, 0, 0]){
        trackTemplate(holeRadius05);
    }
    // Far guide track
    translate([blockWidth-guideTrackRadius - spacingDistance, 0, +0.00]){
        trackTemplate(guideTrackRadius);
    }
}
// Close track
translate([guideTrackRadius+spacingDistance, +0.00, +0.00]){
    trackTemplate(guideTrackRadius);
}

// Body
translate([-blockWidth-1, +0.00, +0.00]){
    rotate([+0.00, +0.00, +0.00]){
        difference(){
            translate([blockWidth/2, -halfBlockThickness/2, 0]){
                cube([blockWidth, halfBlockThickness, blockLength], center = true);
            }
            // First bead rolling track
            translate([blockWidth - hole05Distance, 0, 0]){
                trackTemplate(holeRadius05);
            }
            // Second bead rolling track
            translate([blockWidth - hole04Distance, 0, 0]){
                trackTemplate(holeRadius04);
            }
            // Third bead rolling track
            translate([blockWidth - hole03Distance, 0, 0]){
                trackTemplate(holeRadius03);
            }
            // Fourth bead rolling track
            translate([blockWidth - hole02Distance, 0, 0]){
                trackTemplate(holeRadius02);
            }
            // Fifth bead rolling track
            translate([blockWidth - hole01Distance, 0, 0]){
                trackTemplate(holeRadius01);
            }
            // Sixth bead rolling track
            translate([blockWidth - hole00Distance, 0, 0]){
                trackTemplate(holeRadius00);
            }
            // Far guide track
            translate([blockWidth-guideTrackRadius - spacingDistance, 0, +0.00]){
                trackTemplate(guideTrackRadius);
            }
        }
        // Close track
        translate([guideTrackRadius+spacingDistance, +0.00, +0.00]){
            trackTemplate(guideTrackRadius);
        }
    }
}

// This provides a simple method for making centered cylinder all the same length
module trackTemplate(radius){
    cylinder(blockLength, radius, radius, center = true);
}
```


[User]
Hey, I need a stand for my desktop PC so I can put it on its side under my desk. I'm using a Lenovo Thinkstation M58e, which is pretty slim, and I want to make sure it doesn't get kicked over. I have some basic dimensions I'm thinking about but I'd like the design to be parametric so I can easily adjust it for other devices later.

Here's what I'm envisioning: The stand needs a base with a slot for the PC to sit in. The slot should have a couple of vertical supports with some ridges for extra grip. The stand needs to be reasonably tall to make sure it's stable, probably at least the width of the slot and probably a bit taller. The base needs to be wide enough to not tip over, maybe 2 or 3 times the slot width.

Specifically, I'd like these parameters to control the design:

*   **StandDepth**: The overall depth of the stand (front to back).
*   **StandHeight**: The total height of the stand.
*   **BaseWidth**: The width of the base of the stand.
*   **SlotWidth**: The width of the slot the computer sits in.
*   **BaseHeight**: The height of the connecting bridge between the two vertical supports at the bottom. This is the minimum height of the 'slot'.
*  **MinEdgeWidth**: The minimum width of the edges of the base.
*   **NrRidges**: The number of ridges on the inner supports of the slot.

I'd like the design to be constructed using OpenSCAD. Could you provide me with the code for this? I'm happy to use any libraries that will help make it work, but I'd prefer to use BOSL or BOSL2 if it's appropriate.

[Assistant]
LenovoStand.scad:
```

// Depth of the stand, in mm.
StandDepth = 25;

// Total height of the stand
StandHeight = 100;

// Width of the base of the stand
BaseWidth = 200;

// Width of the slot in the stand. Must be smaller than the width of the base.
SlotWidth = 102;

// Height of the connecting bridge between the two vertical supports.
BaseHeight = 7.5;

// Size of the edges on the top and side.
MinEdgeWidth = 2.5;

// Number of ridges in the support.
NrRidges = 4;

/* [Hidden] */
 ridgeWidth = StandDepth / (2 * NrRidges - 1);

module ridgeDuplicator() {
    for (y = [-StandDepth/2 + ridgeWidth : 2*ridgeWidth : StandDepth/2])
            translate([0,y, 0])
                children(0);
}

module slot() {
    translate([-SlotWidth/2, 0 , BaseHeight])
        union() {
             translate([ 0, -StandDepth/2 - .5 , 0]) cube([SlotWidth, StandDepth + 1, StandHeight - BaseHeight + .5]);
              ridgeDuplicator()
                 translate([0,0,-MinEdgeWidth])
                    cube([SlotWidth, ridgeWidth, MinEdgeWidth + 1]);
        }
}

module base() {
    supportWidth = (BaseWidth - SlotWidth)/2 - MinEdgeWidth;
    supportHeight = StandHeight - MinEdgeWidth;
    supportXOffset = SlotWidth / 2 +supportWidth + MinEdgeWidth;
    supportZOffset = supportHeight + MinEdgeWidth;

    module cutOut() {
        ridgeDuplicator()
             scale([supportWidth, ridgeWidth, supportHeight])rotate(a=90, v=[-1,0,0] ) cylinder( $fn=90);
    }

    difference() {
        hull() {
            cube([BaseWidth, StandDepth, .1], center=true);
            translate([0,0, MinEdgeWidth]) cube([BaseWidth, StandDepth, .1], center=true);
            translate([0,0,StandHeight]) cube([SlotWidth + 2*MinEdgeWidth, StandDepth, .1], center=true);
        }
        translate([supportXOffset, 0, supportZOffset]) cutOut();
        translate([-supportXOffset, 0, supportZOffset]) cutOut();
    }
}

difference() {
    base();
    slot();
}

```


[User]
Hey, I'm looking to get a custom spanner rack designed in OpenSCAD. I have some specific spanner sizes I need to accommodate, and I'd like the rack to be parametric so I can easily adjust it in the future.

I'm envisioning a design similar to the "Spanner_Rack_1_4.scad" file I found online (I've included that below for reference). It has two rails running lengthwise, with angled slots cut into them to hold spanners/wrenches. The main parameters I need to control are:

*   **Spanner Dimensions:**
    *   `SmallSpannerWidth`: Width of the smallest spanner slot (which is also the reduced thickness of the small spanner's shaft).
    *   `SmallSpannerHeight`: Height of the smallest spanner slot (width of the spanner shaft).
    *   `SmallSpannerLength`: Length of the reduced section of the small spanner, which should correspond to how far the slot extends out from the rail.
    *   `LargeSpannerWidth`: Width of the largest spanner slot.
    *   `LargeSpannerHeight`: Height of the largest spanner slot.
    *   `LargeSpannerLength`: Length of the reduced section of the large spanner, also corresponding to the slot's outward extension.

*   **Slot Details:**
    *   `No_of_Slots`: The total number of spanner slots/positions on the rack.
    *   `SlotAngle`: Angle of the slots relative to the vertical. This should be able to take both positive and negative values to lean either way.
    *   `SlotSpacing`: Spacing between each slot.
    *   `RailHeightFactor`: A multiplier that adjusts the height of the rail at each end, based on `SmallSpannerHeight` and `LargeSpannerHeight` (so the rails are thicker than just the size of the slots). I would like the rail height to scale with the slot height to create an angled rail profile.

*   **Quality:**
    *   `Quality`:  Controls the `$fn` parameter, which adjusts the number of facets used for curves. This doesn't affect the overall functionality, but it affects the smoothness of the rack.

Also, I noticed the original design has some cross-bars, which I like. If the overall rack length is more than a certain threshold (say, 100mm), it should include a middle cross-bar. Otherwise, only the two end cross-bars are needed.

It seems the original design just uses basic OpenSCAD primitives; I'm happy to do the same. I'd like the output to be easily modifiable.

Thanks for your help with this!
```
/* [Dimensions of Spanners] */
// Width of smallest spanner slot = thickness of reduced section of small spanner shaft (mm)
SmallSpannerWidth = 3.5; // [3:8]
// Height of smallest spanner slot = width of reduced section of spanner shaft (mm)
SmallSpannerHeight = 7; // [5:12]
// Distance over outside of rails at smallest spanner = length of reduced section of spanner shaft(mm)
SmallSpannerLength = 60; // [40:100]
// Width of largest spanner slot (mm)
LargeSpannerWidth = 6.5; // [5:10]
// Height of largest spanner slot (mm)
LargeSpannerHeight = 13; // [7:20]
// Distance over outside of rails at largest spanner (mm)
LargeSpannerLength = 85; // [60:150]

/* [Slot Details] */
// Numner of No_of_Slots / Spanners
No_of_Slots = 9; // [1:20]
// Angle of No_of_Slots
SlotAngle = -30;  // [-45:45]
// Slot spacing
SlotSpacing = 10;  // [5:15]
// Rail height factor (mulitplier of SmallSpannerHeight and LargeSpannerHeight
RailHeightFactor = 1.75; // [1.25:2.25]

/* [Quality] */
Quality = 60; // [20:200]

/* [Hidden */
$fn = Quality;

RailHS = RailHeightFactor*SmallSpannerHeight;	// Height of rail at small end
RailHL = RailHeightFactor*LargeSpannerHeight;	// Height of rail at large end

StepW = (LargeSpannerWidth-SmallSpannerWidth)/(No_of_Slots-1);	// Step in width between each spanner slot
StepH = (RailHL-RailHS)/(No_of_Slots-1);	// Step in height between each spanner slot

RailL = ((SmallSpannerWidth+LargeSpannerWidth)/2+SlotSpacing)*(No_of_Slots+1);
SlotCOL = LargeSpannerLength+10;	// Length for slot cut out parts

{

/*
 Customizable Spanner / Wrench Rack
 https://www.thingiverse.com/thing:2815926
 by Mr Jan Bassett

 Changelog
 v1.4 - Moved this detail/version block as it was confusing the Customizer
 v1.3 - Corrected an error in the rail spacing
 v1.2 - Modified angle limits to allow the spanners to lean either way
 v1.1 - Added a factor to increase large slot heigth from base
 v1.0 - Original published design

 My uses         Small         Large
					W   H  L    W    H   L   Slots  Angle  Space  Factor
	11 slot -  4.5  8  65  7.0  15  105    11     30     10    1.75
	 9 slot -  3.5  7  60  6.5  13   85     9    -30     10    1.75

 */
	rack();
}

module rack() {
	difference() {
		union() {
			// Rails
			hull() {
				translate([RailL/2,-(SmallSpannerLength/2)+(SmallSpannerWidth),0]) union() {
					cylinder(r=SmallSpannerWidth,h=RailHS-SmallSpannerWidth);
					translate([0,0,RailHS-SmallSpannerWidth/2+-.01]) sphere(r=SmallSpannerWidth);
				}
				translate([-RailL/2,-(LargeSpannerLength/2)+(LargeSpannerWidth/2),0]) union() {
					cylinder(r=SmallSpannerWidth,h=RailHL-SmallSpannerWidth);
					translate([0,0,RailHL-SmallSpannerWidth/2+-.01]) sphere(r=SmallSpannerWidth);
				}
			}
			hull() {
				translate([RailL/2,(SmallSpannerLength/2)-(SmallSpannerWidth),0]) union() {
					cylinder(r=SmallSpannerWidth,h=RailHS-SmallSpannerWidth);
					translate([0,0,RailHS-SmallSpannerWidth/2+-.01]) sphere(r=SmallSpannerWidth);
				}
				translate([-RailL/2,(LargeSpannerLength/2)-(LargeSpannerWidth/2),0]) union() {
					cylinder(r=SmallSpannerWidth,h=RailHL-SmallSpannerWidth);
					translate([0,0,RailHL-SmallSpannerWidth/2+-.01]) sphere(r=SmallSpannerWidth);
				}
			}
			// Cross bars
			BridgeSW=SmallSpannerLength-SmallSpannerWidth+((1/No_of_Slots)*(LargeSpannerLength-SmallSpannerLength));
			translate([(RailL/2)-(1/No_of_Slots)*RailL,0.1,1.5]) hull() {
				translate([0,BridgeSW/2,0]) cube([10,0.1,3],center=true);
				translate([0,-BridgeSW/2,0]) cube([10,0.1,3],center=true);
			}
			BridgeLW=LargeSpannerLength---((1/No_of_Slots)*(LargeSpannerLength-SmallSpannerLength));
			translate([-((RailL/2)-(1/No_of_Slots)*RailL),0.1,1.5]) hull() {
				translate([0,BridgeLW/2,0]) cube([10,0.1,3],center=true);
				translate([0,-BridgeLW/2,0]) cube([10,0.1,3],center=true);
			}
			if (RailL>99) {
				BridgeMW=SmallSpannerLength+((LargeSpannerLength-SmallSpannerLength)/2)-(SmallSpannerWidth+(LargeSpannerWidth-SmallSpannerWidth));
				translate([0,0.1,1.5]) hull() {
					translate([0,BridgeMW/2,0]) cube([10,0.1,3],center=true);
					translate([0,-BridgeMW/2,0]) cube([10,0.1,3],center=true);
				}
			}
		}
		for (Slot=[1:No_of_Slots]) {
			SlotW = (Slot-1)*StepW+SmallSpannerWidth;
			SlotAngleW = ((SlotW-SmallSpannerWidth)/2)+SmallSpannerWidth;
			SlotH = (Slot-1)*StepH+SmallSpannerHeight;
			SlotHO = (RailL/2)-((Slot-0.25)*(SlotSpacing+SlotAngleW))-(sin(SlotAngle)*SlotH);
			SlotHP = SlotHO-(Slot-1)*(SlotAngleW+SlotSpacing);
			SlotVO = ((Slot-1)*1.25*StepH)+(RailHS+(3/4*SmallSpannerWidth));
			SlotVP = SlotVO;
			translate([SlotHO,0,SlotVO]) rotate([0,-SlotAngle,0]) hull() {
				rotate([90,0,0]) cylinder(d=SlotW,h=SlotCOL,center=true);
				translate([0,0,-SlotH]) rotate([90,0,0]) cylinder(d=SlotW,h=SlotCOL,center=true);
			}
		}
	}
}
```

[Assistant]
Spanner_Rack_1_4.scad:
```
/* [Dimensions of Spanners] */
// Width of smallest spanner slot = thickness of reduced section of small spanner shaft (mm)
SmallSpannerWidth = 3.5; // [3:8]
// Height of smallest spanner slot = width of reduced section of spanner shaft (mm)
SmallSpannerHeight = 7; // [5:12]
// Distance over outside of rails at smallest spanner = length of reduced section of spanner shaft(mm)
SmallSpannerLength = 60; // [40:100]
// Width of largest spanner slot (mm)
LargeSpannerWidth = 6.5; // [5:10]
// Height of largest spanner slot (mm)
LargeSpannerHeight = 13; // [7:20]
// Distance over outside of rails at largest spanner (mm)
LargeSpannerLength = 85; // [60:150]

/* [Slot Details] */
// Numner of No_of_Slots / Spanners
No_of_Slots = 9; // [1:20]
// Angle of No_of_Slots
SlotAngle = -30;  // [-45:45]
// Slot spacing
SlotSpacing = 10;  // [5:15]
// Rail height factor (mulitplier of SmallSpannerHeight and LargeSpannerHeight
RailHeightFactor = 1.75; // [1.25:2.25]

/* [Quality] */
Quality = 60; // [20:200]

/* [Hidden */
$fn = Quality;

RailHS = RailHeightFactor*SmallSpannerHeight;	// Height of rail at small end
RailHL = RailHeightFactor*LargeSpannerHeight;	// Height of rail at large end

StepW = (LargeSpannerWidth-SmallSpannerWidth)/(No_of_Slots-1);	// Step in width between each spanner slot
StepH = (RailHL-RailHS)/(No_of_Slots-1);	// Step in height between each spanner slot

RailL = ((SmallSpannerWidth+LargeSpannerWidth)/2+SlotSpacing)*(No_of_Slots+1);
SlotCOL = LargeSpannerLength+10;	// Length for slot cut out parts

{

/*
 Customizable Spanner / Wrench Rack
 https://www.thingiverse.com/thing:2815926
 by Mr Jan Bassett

 Changelog
 v1.4 - Moved this detail/version block as it was confusing the Customizer
 v1.3 - Corrected an error in the rail spacing
 v1.2 - Modified angle limits to allow the spanners to lean either way
 v1.1 - Added a factor to increase large slot heigth from base
 v1.0 - Original published design

 My uses         Small         Large
					W   H  L    W    H   L   Slots  Angle  Space  Factor
	11 slot -  4.5  8  65  7.0  15  105    11     30     10    1.75
	 9 slot -  3.5  7  60  6.5  13   85     9    -30     10    1.75

 */
	rack();
}

module rack() {
	difference() {
		union() {
			// Rails
			hull() {
				translate([RailL/2,-(SmallSpannerLength/2)+(SmallSpannerWidth),0]) union() {
					cylinder(r=SmallSpannerWidth,h=RailHS-SmallSpannerWidth);
					translate([0,0,RailHS-SmallSpannerWidth/2+-.01]) sphere(r=SmallSpannerWidth);
				}
				translate([-RailL/2,-(LargeSpannerLength/2)+(LargeSpannerWidth/2),0]) union() {
					cylinder(r=SmallSpannerWidth,h=RailHL-SmallSpannerWidth);
					translate([0,0,RailHL-SmallSpannerWidth/2+-.01]) sphere(r=SmallSpannerWidth);
				}
			}
			hull() {
				translate([RailL/2,(SmallSpannerLength/2)-(SmallSpannerWidth),0]) union() {
					cylinder(r=SmallSpannerWidth,h=RailHS-SmallSpannerWidth);
					translate([0,0,RailHS-SmallSpannerWidth/2+-.01]) sphere(r=SmallSpannerWidth);
				}
				translate([-RailL/2,(LargeSpannerLength/2)-(LargeSpannerWidth/2),0]) union() {
					cylinder(r=SmallSpannerWidth,h=RailHL-SmallSpannerWidth);
					translate([0,0,RailHL-SmallSpannerWidth/2+-.01]) sphere(r=SmallSpannerWidth);
				}
			}
			// Cross bars
			BridgeSW=SmallSpannerLength-SmallSpannerWidth+((1/No_of_Slots)*(LargeSpannerLength-SmallSpannerLength));
			translate([(RailL/2)-(1/No_of_Slots)*RailL,0.1,1.5]) hull() {
				translate([0,BridgeSW/2,0]) cube([10,0.1,3],center=true);
				translate([0,-BridgeSW/2,0]) cube([10,0.1,3],center=true);
			}
			BridgeLW=LargeSpannerLength---((1/No_of_Slots)*(LargeSpannerLength-SmallSpannerLength));
			translate([-((RailL/2)-(1/No_of_Slots)*RailL),0.1,1.5]) hull() {
				translate([0,BridgeLW/2,0]) cube([10,0.1,3],center=true);
				translate([0,-BridgeLW/2,0]) cube([10,0.1,3],center=true);
			}
			if (RailL>99) {
				BridgeMW=SmallSpannerLength+((LargeSpannerLength-SmallSpannerLength)/2)-(SmallSpannerWidth+(LargeSpannerWidth-SmallSpannerWidth));
				translate([0,0.1,1.5]) hull() {
					translate([0,BridgeMW/2,0]) cube([10,0.1,3],center=true);
					translate([0,-BridgeMW/2,0]) cube([10,0.1,3],center=true);
				}
			}
		}
		for (Slot=[1:No_of_Slots]) {
			SlotW = (Slot-1)*StepW+SmallSpannerWidth;
			SlotAngleW = ((SlotW-SmallSpannerWidth)/2)+SmallSpannerWidth;
			SlotH = (Slot-1)*StepH+SmallSpannerHeight;
			SlotHO = (RailL/2)-((Slot-0.25)*(SlotSpacing+SlotAngleW))-(sin(SlotAngle)*SlotH);
			SlotHP = SlotHO-(Slot-1)*(SlotAngleW+SlotSpacing);
			SlotVO = ((Slot-1)*1.25*StepH)+(RailHS+(3/4*SmallSpannerWidth));
			SlotVP = SlotVO;
			translate([SlotHO,0,SlotVO]) rotate([0,-SlotAngle,0]) hull() {
				rotate([90,0,0]) cylinder(d=SlotW,h=SlotCOL,center=true);
				translate([0,0,-SlotH]) rotate([90,0,0]) cylinder(d=SlotW,h=SlotCOL,center=true);
			}
		}
	}
}
```


[User]
I'm looking to generate QR codes in OpenSCAD, and I'd like it to be as robust as possible, handling different string inputs, different error correction levels, and different masking patterns. I want to be able to specify whether I'm using fixed size for the entire code or fixed pixel sizes. I need the generator to handle byte encoding at the very least, and potentially numeric and alphanumeric encoding methods as well.

I'm thinking I'll need a main module, something like `QR_code(string, encoding, min_ec, fixed_size, mask)`, which will take the string to be encoded, the encoding type, the minimum error correction level, whether we're fixing size or pixel size, and the masking pattern to use. The error correction should use the highest available level for the smallest size available given the string.

Within this, I'd need a module to draw the position patterns, like `Position_pattern()`. These should be the familiar squares in the corners and along the sides. I'll also need an `Alignment_pattern()` module for the smaller alignment squares, and a module to draw these when needed depending on the version, which will be `draw_alignment_patterns(version)`. A `Timing_pattern(version)` module would take the version as an input and draw the timing patterns. Then of course `Format_pattern(sequence, version)` which will need to handle the format sequence and use the version to draw it in the appropriate locations.

Then I need to deal with all the encoding logic and output the modules needed to render this, like `draw_encoded_string(encoded_string, version, mask)` which will need to iterate through all the encoded bits and draw the black squares where the bits are. Then it needs to get down to the core bit setting with a `draw(string, version, bit, xy, mask)` and an internal function `_draw(string, version, bit, x, y, mask)`.

All the necessary functions would include a version selector `version(string, encoding, ec)`, an error correction selector `ec(string,ec,version)`, a `encode(string, ec, version)`, a data encoder `encode_data(string, ec, version)`, error encoder `encode_error(s, ec, v)`, error data generator `error_data(s, ec, v)`, the block error generator `error_block(s, ec, v, b)`, a function to calculate the Galois field with `pad_eb(s,count)`, another to encode the error block with a given formula `encode_eb(s,f)`, a base encoding function `_encode_eb(s,f,s0,p)`, the pow and log helpers for the Galois math `pow_a(x)` and `log_a(x)`, padding the data `pad_data(string, ec, v)`, padding the bits `padding_bits(ec, v)`, bit manipulation `bits(char)`, extracting individual bits from a character`_bit(char, bit)`, and converting between hex and int representations for the characters and data, and finally a method to calculate the mask at a given location and select the proper mask pattern `mask(x, y, m)`, and functions for each of the 8 masks, e.g. `mask0(x,y)` etc.

Also, I would like these functions for calculating the location of the data bits: `position(bit, version)`, `reserved(x,y,v)`, `_position(b,x,y,v,d)`, and `_next_pos(b,x,y,v,d)`. Finally string conversion functions: `str_to_hex(string,char)`, and `int_to_hex(i)`, and logical operations `int(char, i)`, `ec_to_int(ec)`, `format_sequence(ec,mask)`, and `xor(a, b)`, and `bitwise_xor(a, b)`.

I don't need any specific libraries here - just pure OpenSCAD code.

[Assistant]
QR_generator.scad:
```
// preview[view:"north", tilt:"top"]

//The string to encode.
String = "http://www.thingiverse.com/thing:258542";

//The minimum error correction level - higher means it's more stable. Encoding will use the highest available error correction for the smallest size available.
Min_Error_Correction_level = "medium"; //[low,medium,quartile,high]

//Which masking pattern to use. The code should scan with any.
Mask = 3; //[0:7]

/* [Hidden] */

//Whether we set a fixed size for the output (true) or use fixed size pixels (false)
Fixed_size = false; //[true,false]

//The encoding method
Encoding = "byte"; //["num","alphanum","byte"]

coefficients = [1,2,4,8,16,32,64,128,29,58,116,232,205,135,19,38,76,152,45,90,180,117,234,201,143,3,6,12,24,48,96,192,157,39,78,156,37,74,148,53,106,212,181,119,238,193,159,35,70,140,5,10,20,40,80,160,93,186,105,210,185,111,222,161,95,190,97,194,153,47,94,188,101,202,137,15,30,60,120,240,253,231,211,187,107,214,177,127,254,225,223,163,91,182,113,226,217,175,67,134,17,34,68,136,13,26,52,104,208,189,103,206,129,31,62,124,248,237,199,147,59,118,236,197,151,51,102,204,133,23,46,92,184,109,218,169,79,158,33,66,132,21,42,84,168,77,154,41,82,164,85,170,73,146,57,114,228,213,183,115,230,209,191,99,198,145,63,126,252,229,215,179,123,246,241,255,227,219,171,75,150,49,98,196,149,55,110,220,165,87,174,65,130,25,50,100,200,141,7,14,28,56,112,224,221,167,83,166,81,162,89,178,121,242,249,239,195,155,43,86,172,69,138,9,18,36,72,144,61,122,244,245,247,243,251,235,203,139,11,22,44,88,176,125,250,233,207,131,27,54,108,216,173,71,142];
inv_coef = [255,0,1,25,2,50,26,198,3,223,51,238,27,104,199,75,4,100,224,14,52,141,239,129,28,193,105,248,200,8,76,113,5,138,101,47,225,36,15,33,53,147,142,218,240,18,130,69,29,181,194,125,106,39,249,185,201,154,9,120,77,228,114,166,6,191,139,98,102,221,48,253,226,152,37,179,16,145,34,136,54,208,148,206,143,150,219,189,241,210,19,92,131,56,70,64,30,66,182,163,195,72,126,110,107,58,40,84,250,133,186,61,202,94,155,159,10,21,121,43,78,212,229,172,115,243,167,87,7,112,192,247,140,128,99,13,103,74,222,237,49,197,254,24,227,165,153,119,38,184,180,124,17,68,146,217,35,32,137,46,55,63,209,91,149,188,207,205,144,135,151,178,220,252,190,97,242,86,211,171,20,42,93,158,132,60,57,83,71,109,65,162,31,45,67,216,183,123,164,118,196,23,73,236,127,12,111,246,108,161,59,82,41,157,85,170,251,96,134,177,187,204,62,90,203,89,95,176,156,169,160,81,11,245,22,235,122,117,44,215,79,174,213,233,230,231,173,232,116,214,244,234,168,80,88,175];

version_table = [[[17,[[19,7]],1],[14,[[16,10]],1],[11,[[13,13]],1],[7,[[9,17]],1],0],
						[[32,[[34,10]],1],[26,[[28,16]],1],[20,[[22,22]],1],[14,[[16,28]],1],7],
						[[53,[[55,15]],1],[42,[[44,26]],1],[32,[[17,18],[17,18]],1],[24,[[13,22],[13,22]],2],7],
						[[78,[[80,20]],1],[62,[[32,18],[32,18]],2],[46,[[24,26],[24,26]],2],[34,[[9,16],[9,16],[9,16],[9,16]],4],7],
						[[106,[[108,26]],1],[84,[[43,24],[43,24]],2],[60,[[15,18],[15,18],[16,18],[16,18]],4],[44,[[11,22],[11,22],[12,22],[12,22]],4],7],
						[[134,[[68,18],[68,18]],2],[106,[[27,16],[27,16],[27,16],[27,16]],4],[74,[[19,24],[19,24],[19,24],[19,24]],4],[58,[[15,28],[15,28],[15,28],[15,28]],4],7]
];

error_formula = ["","","001901","","","0071A4A6770A","0074008605B00F","0057E59295EE6615","00AFEED0F9D7FCC41C","","00FB432E3D7646405E202D","","","004A98B06456646A6882DACE8C4E","00C7F99B30BE7CDA89D857CF3B165B","0008B73D5BCA25333A3AED8C7C056369","0078686B6D66A14C035BBF93A9C2E178","002B8BCE4E2BEF7BCED69318639627F3A388","00D7EA9E5EB86176AA4FBB9894FCB305626099","","00113C4F323DA31ABBCAB4DDE153EF9CA4D4D4BCBE","","00D2ABF7F25DE60E6DDD35C84A08AC6250DB86A069A5E7","","00E5798730D375FB7E9FB4A998C0E2E4DA6F0075E85760E315","","00AD7D9E0267B6761191C96F1CA535A115F58E0D6630E39991DA46","","00A8DFC868E0EA6CB46EBEC393CD1BE8C9152BF5572AC3D477F225097B","","0029AD9198D81FB3B632306E56EF60DE7D2AADE2C1E0829C25FBD8EE28C0B4","","0A066ABEF9A70443D18A8A20F27B591B78B9509C2645AB3C1CDE5034FEB9DCF1","","006F4D925E1A156C13695E71C1568CA37D3A9EE5EFDA673846723DB781A70D623E8133","","00C8B76210AC1FF6EA3C987300A79871F8EE6B123FDA2557D269B1784A79C475FB71E91E2F083B744FA1FC6280CD80A1F739A338EB6A351ABBAEE268AA07AF23B57258292FA37D864814E835230F","","","","","","00FA67DDE6191289E700033AF2DDBF6E54E608BC6A60930F838B2265DF2765D5C7EDFEC97BABA2C2753260","","00BE073D7947F64537A8BC59F3BF19487B09910EF701EE2C4E8F3EE07E767244A334C2D993CCA92582716649B5","","00705E5870FDE0CA73BB6359053671812C3A1087D8A9D3240104603CF14968EA08F9F577AE34199DE02BCADF13520F","","00E419C482D3923C18FB5A2766F03DB23F2E7B7312DD6F87A0B6CD6BCE5F9678B85B15F79C8CEEBF0B5EE35432A327226C","","00E87D9DA1A409762ED163CBC12303D16FC3F2CBE12E0D20A07ED182A0F2D7F24B4D2ABD2071417C45E472EBAF7CAAD7E885CD","","00743256BA32DCFB59C02E567F7C13B8E997D7160E3B9125F2CB86FE59BE5E3B417C7164E9EB79164C566127F2C8DC6521EFFE7433","","00B71AC957D2DD71152E412D32EEB8F9E1663AD1DA6DA51A5FB8C034F523FEEEAFAC4F7B197A2B786CD75080C9EB08993B651FC64C1F9C","","006A786B9DA4D87074025BF8A324C9CAE50690FE9B87D0AAD10C8B7F8EB6F9B1AEBE1C0A55EFB8657C98CE6017A33D1BC4F7979ACACF143D0A","","0052741AF7421B3E6BFCB6C8B9EB37FBF2D2909AEDB08DC0F898F9CE55FD8E41A57D17181E7AF0D60681DA1D917F86CEF5751D293F9F8EE97D947B","","006B8C1A0C098DF3C5E2C5DB2DD365DB781CB57F0664F702CDC63973DB656DA0522526EE31A0D179560B7C1EB55419C2574166BEDC461BD110590721F0","","0041CA716247DFF876D65E007A251702E43A790769874EF376464CDF594832466FC211D47EB523DD75EB0BE595937BD5287306C8641AF6B6DA7FD724BA6E6A","","002D33AF09079E9F3144775C7BB1CCBBFEC84E8D95771A7F35A05DC7D41D18919CD096DAD104D85B2FB8922F8CC3C37DF2EE3F636C8CE6F21FCC0BB2F3D99CD5E7","","000576DEB48888A2332E750DD751118BF7C5AB5FAD4189B2446F5F652948D6A9C55F072C9A4D6FEC28798F3F5750FDF07ED94D22E86A32A8524C92436AAB19845D2D69","","00F79FDF21E05D4D465AA020FE2B965465BECD85343CCAA5DCCB975D540F54FDADA059E334C7615FE734B1297D89F1A6E17602362052D7AFC62BEEEB1B65B87F030508A3EE"];

color("black")
QR_code(String, Encoding, Min_Error_Correction_level, Fixed_size, Mask);

module QR_code(string, encoding, min_ec, fs, mask) {
	version = version(string, encoding, ec_to_int(min_ec));
	ec=ec(string,ec_to_int(min_ec),version);
	encoded_string = version<10 ? encode(str("4",int_to_hex(len(string)),str_to_hex(string),"0"), ec, version) : encode(str("4",int_to_hex(floor(len(string)/256)),int_to_hex(len(string)%256),str_to_hex(string),"0"), ec, version);

    offset = 8 + (version * 2);
    translate(v=[ -offset, -offset, 0 ])

	union() {
		Position_pattern();
		translate(v=[10+4*version,0,0])
		Position_pattern();
		translate(v=[0,10+4*version,0])
		Position_pattern();
		translate(v=[9+4*version,8,0])
		cube([1,1,1]);
		Format_pattern(format_sequence(ec,mask), version);
		Timing_pattern(version);
		draw_alignment_patterns(version);
		draw_encoded_string(encoded_string, version, mask);
	}
}

module draw_encoded_string(encoded_string, version, mask) {
	for (bit=[0:len(encoded_string)-1]) {
		draw(encoded_string, version, bit, position(bit,version), mask);
	}
}

module draw(string, version, bit, xy, mask) {
	_draw(string, version, bit, floor(xy/1000), xy%1000, mask);
}

module _draw(string, version, bit, x, y, mask) {
	if (xor(string[bit]=="1",mask(x,y,mask))) {
		translate(v=[x,y,0])
		cube([1,1,1]);
	}
}

module draw_alignment_patterns(version) {
	if (version == 1) {
	} else if (version < 7) {
		translate(v=[8+4*version,8+4*version,0])
		Alignment_pattern();
	} else if (version < 14) {
		for (i=[0:2]) {
			for (j=[0:2]) {
				if ((i!=0 && j!=0) || i==1 || j==1) {
					translate(v=[2*i*(version+1)+4,2*j*(version+1)+4,0])
					Alignment_pattern();
				}
			}
		}
	}
}

module Position_pattern() {
	difference() {
		cube([7,7,1]);
		translate(v=[1,1,-1])
		cube([5,5,3]);
	}
	translate(v=[2,2,0])
	cube([3,3,1]);
}

module Alignment_pattern() {
	difference() {
		cube([5,5,1]);
		translate(v=[1,1,-1])
		cube([3,3,3]);
	}
	translate(v=[2,2,0])
	cube([1,1,1]);
}

module Format_pattern(sequence, version) {
	for (i=[0:5]) {
		if (sequence[14-i]=="1") {
			translate(v=[i,8,0])
			cube([1,1,1]);
			translate(v=[8,16+4*version-i,0])
			cube([1,1,1]);
		}
	}
	for (i=[6:7]) {
		if (sequence[14-i]=="1") {
			translate(v=[i+1,8,0])
			cube([1,1,1]);
			translate(v=[8,16+4*version-i,0])
			cube([1,1,1]);
		}
	}
	for (i=[8]) {
		if (sequence[14-i]=="1") {
			translate(v=[8,15-i,0])
			cube([1,1,1]);
			translate(v=[2+4*version+i,8,0])
			cube([1,1,1]);
		}
	}
	for (i=[9:14]) {
		if (sequence[14-i]=="1") {
			translate(v=[8,14-i,0])
			cube([1,1,1]);
			translate(v=[2+4*version+i,8,0])
			cube([1,1,1]);
		}
	}
}

module Timing_pattern(version) {
	for (i=[0:2*version]) {
		translate(v=[2*i+8,6,0])
		cube([1,1,1]);
		translate(v=[6,2*i+8,0])
		cube([1,1,1]);
	}
}

function substring(string,start,end,output="") = start==end ? output : str(string[start],substring(string,start+1,end,output));

function encode(string, ec, version) = str(encode_data(pad_data(string, ec, version), ec, version), encode_error(pad_data(string, ec, version), ec, version), padding_bits(ec, version));

function encode_error(s, ec, v) = encode_error_data(error_data(s, ec, v), ec, v);

function encode_error_data(string, ec, version, pos=0, byte=0, block=0) =
	version_table[version-1][ec][1][block][1]>byte ? str(bits(hex_to_int(string[pos])*16+hex_to_int(string[pos+1])), encode_error_data(string, ec, version, _next_epos(version, ec, pos, byte, block), _next_ebyte(version, ec, pos, byte, block), _next_eblock(version, ec, pos, byte, block))) : "";
function _next_epos(v,ec,p,y,b) = b<len(version_table[v-1][ec][1])-1 ? p+2*version_table[v-1][ec][1][b][1] :
	y<version_table[v-1][ec][1][0][1]-1 ? 2*(y+1) :
	y<version_table[v-1][ec][1][b][1]-1 ? 2*(version_table[v-1][ec][2]*version_table[v-1][ec][1][0][1]+y+1) : 2*(y+1);
function _next_ebyte(v,ec,p,y,b) = b<len(version_table[v-1][ec][1])-1 ? y : y+1;
function _next_eblock(v,ec,p,y,b) = b<len(version_table[v-1][ec][1])-1 ? b+1 :
	y<version_table[v-1][ec][1][0][1]-1 ? 0 :
	y<version_table[v-1][ec][1][b][1]-1 ? version_table[v-1][ec][2] : 0;

function error_data(s, ec, v, b=0) = b<len(version_table[v-1][ec][1]) ? str(error_block(substring(s,0,2*version_table[v-1][ec][1][b][0]), ec, v, b),error_data(substring(s,2*version_table[v-1][ec][1][b][1],len(s)), ec, v, b+1)) : "";
//function error_data(s, ec, v, b=0) = error_block(str_to_hex(substring(substring(s,version_table[v][ec][1][b][1],len(s)),0,version_table[v][ec][1][b][1])), ec, v, b);

function error_block(s, ec, v, b) = encode_eb(pad_eb(s,version_table[v-1][ec][1][b][1]),error_formula[version_table[v-1][ec][1][b][1]]);
//function error_block(s, ec, v, b) = str(version_table[v][ec][1][b][1]);

function pad_eb(s,count) = count<=0 ? s : pad_eb(str(s,"00"),count-1);

function encode_eb(s,f) = len(s)<=len(f)-2 ? s : encode_eb(substring(_encode_eb(s,f,log_a(hex_to_int(s[0])*16+hex_to_int(s[1]))),2,len(s)),f);

function _encode_eb(s,f,s0,p=0) = p==len(f) ? substring(s,p,len(s)) :
	str(int_to_hex(bitwise_xor(pow_a(((hex_to_int(f[p])*16+hex_to_int(f[p+1]))+s0)%255),hex_to_int(s[p])*16+hex_to_int(s[p+1]))),_encode_eb(s,f,s0,p+2));

function pow_a(x) = coefficients[x];
function log_a(x) = inv_coef[x];

function encode_data(string, ec, version, pos=0, byte=0, block=0) =
	version_table[version-1][ec][1][block][0]>byte ? str(bits(hex_to_int(string[pos])*16+hex_to_int(string[pos+1])), encode_data(string, ec, version, _next_dpos(version, ec, pos, byte, block), _next_dbyte(version, ec, pos, byte, block), _next_dblock(version, ec, pos, byte, block))) : "";
function _next_dpos(v,ec,p,y,b) = b<len(version_table[v-1][ec][1])-1 ? p+2*version_table[v-1][ec][1][b][0] :
	y<version_table[v-1][ec][1][0][0]-1 ? 2*(y+1) :
	y<version_table[v-1][ec][1][b][0]-1 ? 2*(version_table[v-1][ec][2]*version_table[v-1][ec][1][0][0]+y+1) : 2*(y+1);
function _next_dbyte(v,ec,p,y,b) = b<len(version_table[v-1][ec][1])-1 ? y : y+1;
function _next_dblock(v,ec,p,y,b) = b<len(version_table[v-1][ec][1])-1 ? b+1 :
	y<version_table[v-1][ec][1][0][0]-1 ? 0 :
	y<version_table[v-1][ec][1][b][0]-1 ? version_table[v-1][ec][2] : 0;

function padding_bits(ec, v, b=0) = b<version_table[v-1][4] ? str("0",padding_bits(ec,v,b+1)) : "";

function pad_data(string, ec, v, pad_string="") = len(string)+len(pad_string)>2*version_table[v-1][ec][0]+2+floor((v+20)/30) ? str(string,pad_string) :
	len(pad_string)%4 == 0 ? pad_data(string, ec, v, str(pad_string,"EC")) :
	pad_data(string, ec, v, str(pad_string,"11"));

function bits(char, bit=0) = bit<7 ? str(_bit(char,bit),bits(char - (_bit(char,bit) * pow(2,7-bit)),bit+1)) : _bit(char,bit);
function _bit(char, bit) = char>=pow(2,7-bit) ? 1 : 0;

function hex_bits(chars) = bits(hex_to_int(chars[0])*16+hex_to_int(chars[1]));
function hex_to_int(char) = search(char,"0123456789ABCDEF")[0];

function int(char, i=0) = (chr(i) == char) ? i : int(char, i+1);
function ec_to_int(ec) = ec=="low" ? 0 :
								ec=="medium" ? 1 :
								ec=="quartile" ? 2 : 3;

function format_sequence(ec,mask) = ["101010000010010","101000100100101","101111001111100","101101101001011","100010111111001","100000011001110","100111110010111","100101010100000","111011111000100","111001011110011","111110110101010","111100010011101","110011000101111","110001100011000","110110001000001","110100101110110","001011010001001","001001110111110","001110011100111","001100111010000","000011101100010","000001001010101","000110100001100","000100000111011","011010101011111","011000001101000","011111100110001","011101000000110","010010010110100","010000110000011","010111011011010","010101111101101"][bitwise_xor(ec,1)*8+mask];

function version(string, encoding, ec, v=1) = len(string)<=version_table[v-1][ec][0] ? v : version(string, encoding, ec, v+1);

function ec(s,ec,v) = ec<4 && len(s)<=version_table[v-1][ec][0] ? ec(s,ec+1,v) : ec-1;

function xor(a, b) = (a||b)&& !(a&&b);

function bitwise_xor(a, b) = (a==0 && b==0) ? 0 : 2*bitwise_xor(floor(a/2), floor(b/2))+(xor(a%2==1,b%2==1)?1:0);

function mask(x, y, m) = m==0 ? mask0(x,y) :
								m==1 ? mask1(x,y) :
								m==2 ? mask2(x,y) :
								m==3 ? mask3(x,y) :
								m==4 ? mask4(x,y) :
								m==5 ? mask5(x,y) :
								m==6 ? mask6(x,y) :
								mask7(x,y);
function mask0(x,y) = (x+y)%2 == 0;
function mask1(x,y) = x%2 == 0;
function mask2(x,y) = y%3 == 0;
function mask3(x,y) = (x+y)%3 == 0;
function mask4(x,y) = (floor(x/2)+floor(y/3))%2 == 0;
function mask5(x,y) = (x*y)%2 + (x*y)%3 == 0;
function mask6(x,y) = ((x*y)%2 + (x*y)%3)%2 == 0;
function mask7(x,y) = ((x+y)%2 + (x*y)%3)%2 == 0;

function position(bit, version) = _position(bit,4*version+16,4*version+16,version,-1);
function reserved(x,y,v) = x==6 || y==6 ||
			(x<9 && y<9) || (x<9 && y>4*v+8) || (x>4*v+8 && y<9) ||
			(v>6 && x>4*v+5 && y<6) || (v>6 && y>4*v+5 && x<6) ||
			(v>1 && x>=4*v+8 && x<=4*v+12 && y>=4*v+8 && y<=4*v+12) ||
			(v>=7 && v<=13 && ((x>=2*v+6 && x<=2*v+10 && y%(2*v+2)>=4 && y%(2*v+2)<=8) || (y>=2*v+6 && y<=2*v+10 && x%(2*v+2)>=4 && x%(2*v+2)<=8)));
function _position(b,x,y,v,d) = b==0 && !reserved(x,y,v) ? 1000*x+y :
	reserved(x,y,v) ? _next_pos(b,x,y,v,d) : _next_pos(b-1,x,y,v,d);
function _next_pos(b,x,y,v,d) = (y == 6) || ((y>6 && y%2 == 0) || (y<6 && y%2 == 1)) ? _position(b,x,y-1,v,d) :
	 (d<0 && x == 0) || (d>0 && x == 4*v+16) ? _position(b,x,y-1,v,-d) :
	_position(b,x+d,y+1,v,d);

function str_to_hex(string,char=0) = char==len(string) ? "" : str("0123456789ABCDEF"[floor(int(string[char])/16)],"0123456789ABCDEF"[int(string[char])%16],str_to_hex(string,char+1));

function int_to_hex(i) = str("0123456789ABCDEF"[floor(i/16)],"0123456789ABCDEF"[i%16]);
```


[User]
I'm looking to generate some 3D printable powder scoops using OpenSCAD. I've seen a few designs out there, but I'd like something parametric so I can easily make scoops of various sizes.

Essentially, each scoop should be composed of a hemispherical base, with a cylinder on top, both having the same radius. The combined volume of these two shapes will determine the scoop's capacity. I'd like the hemisphere to account for 1/3 of the volume and the cylinder to account for the remaining 2/3.

I need the design to include a handle, which should be a cylinder coming out from the side of the scoop (specifically at the midpoint of the height of the cylindrical part). The handle should have a comfortable grip at the end that consists of a hull between two spheres, and should include a label indicating the scoop's capacity.

I would like a few pre-set options:
   1.  A "Lee set" of scoops that match the capacities of the Lee Precision dippers. Those capacities, in cubic centimeters, are 0.17, 0.3, 0.5, 0.7, 1.0, 1.3, 1.6, 1.9, 2.2, 2.5, 2.8, 3.1, 3.4, 3.7, 4.0, and 4.3.
   2.  A "Super set" of scoops that ranges from 0.1cc to 5.0cc in 0.1cc increments.
   3. And a single custom scoop that I can define the CC value for.

I'd like the ability to tweak certain parameters, such as:

*   `EXTRUDER_NOZZLE_DIAMETER`: The diameter of my 3D printer's nozzle. Default to 0.04cm.
*   `CUP_WALL_SIZE`: The thickness of the scoop's wall, usually twice the nozzle diameter. Default to `EXTRUDER_NOZZLE_DIAMETER * 2`.
*   `HANDLE_DIAMETER`: The diameter of the handle itself. Default to 0.4cm.
*   `HANDLE_LENGTH`: The length of the handle (not including the grip). Default to 8cm.
*   `GRIP_DIAMETER`: The diameter of the spherical parts of the grip. Default to 0.8cm.
*   `CUSTOM_LABEL`: a label that overrides the cc value.

The capacity `SCOOP_CC` should also be configurable when selecting the single custom scoop option.

The units should all be in centimeters.

Could you generate the necessary OpenSCAD files for this? I don't need any special libraries for this design.

[Assistant]
powder_scoops.scad:
```
// CUSTOMIZER PARAMETERS

// "roundness"
$fn=48;
// 0.04cm = 0.4mm; cup wall = nozzle * 2
EXTRUDER_NOZZLE_DIAMETER=0.04;
// 0.8mm (dremel has a 0.4mm nozzle)
CUP_WALL_SIZE=EXTRUDER_NOZZLE_DIAMETER*2;
// 0.4 cm
HANDLE_DIAMETER=0.4;
// 8 cm
HANDLE_LENGTH=8;
// 0.8 cm
GRIP_DIAMETER=0.8;
// 0.17 cc
SCOOP_CC=0.17;
// Leave blank for CC
CUSTOM_LABEL="";

// we'll use a hemisphere and a cylinder with the same radius
// that add together to equal the required cc
// hemisphere volume: V = 2/3 * π * r^3
// cylinder volume: V = π * r^2 * h

// for a known cc cup, let's use a hemisphere to store
// 1/3 of the capacity, and the cylinder on top to store the rest.
// cc * 1/3 = 2/3 * π * r^3
// cc / 3 = 2 * π * r^3 / 3
// cc = 2 * π * r^3
// r^3 = cc / (2 * π)
// r = cuberoot(cc / (2 * π))
function radiusForCC(cc) = pow(cc/(2*PI), 1/3);

// since we know the hemisphere is taking 1/3 of the volume let's do 2/3 with the cylinder
// pass in the radius of the hemisphere
// cc * 2/3 = π * r^2 * h
// h =  (cc * 2/3) / (π * r^2)
function heightForCC(cc, radius) = (cc*2/3)/(PI*pow(radius, 2));

module createScoops(minSize, maxSize, stepSize) {
    numScoops = ((maxSize-minSize)/stepSize);
    loops = [0:ceil(numScoops)];
    for(i=loops) {
        size = minSize + i*stepSize;
        echo(str("Creating scoop ",i+1, " ", size, " cc"));
        translate([i * 3, 0, 0]) createScoop(size);
    }
}

module createScoop(cc) {
    // lets compute the size of the cavity
    radius = radiusForCC(cc);
    height = heightForCC(cc, radius);

    union() {
        createCup(radius, height);

        // we want to have around HANDLE_LENGTH cm handles
        // not including the radius of the cup
        createHandle(cc, HANDLE_LENGTH, radius, [0, 0, height/2]);
    }
}

module createHandle(cc, length, radius, offset) {
    // shaft
    difference() {
        translate(offset) rotate([90,0,0]) cylinder(d=HANDLE_DIAMETER, h=length);
        cylinder(r = radius, h=length);
    }

    // grip
    union() {
        translate([0,-length/2,0]) translate(offset) rotate([90,0,0])
        difference() {
            hull() {
                //translate([0,0,0]) sphere(d=HANDLE_DIAMETER);
                //translate([HANDLE_DIAMETER/2,0,length/2]) sphere(d=HANDLE_DIAMETER);
                //translate([-HANDLE_DIAMETER/2,0,length/2]) sphere(d=HANDLE_DIAMETER);
                //translate([0,-0.1,length/2]) sphere(d=HANDLE_DIAMETER);
                translate([0,0,0]) sphere(d=GRIP_DIAMETER);
                translate([0,0,length/2]) sphere(d=GRIP_DIAMETER);
            }
            translate([-GRIP_DIAMETER/2, HANDLE_DIAMETER/2,-HANDLE_DIAMETER]) cube(size=length);
        }

        // descriptive text
        text = CUSTOM_LABEL == "" ? str(cc, "cc") : LABEL;
        translate([0,-(length*.99),0.08]) translate(offset)
        rotate([0,0,270])
        linear_extrude(height = HANDLE_DIAMETER/2) {
           text(text = text, font = "Liberation Sans:style=Bold", size = HANDLE_DIAMETER, valign="center", halign = "right");
        }

    }
}

module createCup(radius, height) {

    // hv + cv = cc or...
    // cc = 2/3 * π * r^3 + π * r^2 * h
    //
    difference() {
        // cup
        union() {
            sphere(r = radius + CUP_WALL_SIZE);
            cylinder(r = radius + CUP_WALL_SIZE, h=height);
        }

        // cavity (matches desired cc)
        sphere(r = radius);
        cylinder(r=radius, h=height + 2);
    }
}

createScoop(SCOOP_CC);
//createScoop(5.0);
//createScoops(0.3, 0.7, 0.2);
//translate([0,-15,0]) createScoops(10.0, 15.0, 0.1);

// 211002
// fixed up customizer
// changed all measurements to metric
// removed min() from radiusForCC?
// cleaned up code and added some comments
```
powder_scoops.scad:
```
$fn=48;

// we'll use a hemisphere and a cylinder with the same radius
// that add together to equal the required cc
// hemisphere volume: V = 2/3 * π * r^3
// cylinder volume: V = π * r^2 * h

// for a known cc cup, let's use a hemisphere to store
// 1/3 of the capacity, and the cylinder on top to store the rest.
// cc * 1/3 = 2/3 * π * r^3
// cc / 3 = 2 * π * r^3 / 3
// cc = 2 * π * r^3
// r^3 = cc / (2 * π)
// r = cuberoot(cc / (2 * π))
function radiusForCC(cc) = pow(cc/(2*PI), 1/3);

// since we know the hemisphere is taking 1/3 of the volume let's do 2/3 with the cylinder
// pass in the radius of the hemisphere
// cc * 2/3 = π * r^2 * h
// h = (cc * 2/3) / (π * r^2)
function heightForCC(cc, radius) = (cc*2/3)/(PI*pow(radius, 2));

EXTRUDER_NOZZLE_DIAMETER=0.04;
CUP_WALL_SIZE=EXTRUDER_NOZZLE_DIAMETER*2; // 0.8mm (dremel has a 0.4mm nozzle)
HANDLE_DIAMETER=0.4; // 4mm
GRIP_DIAMETER=0.8;

module createScoops(minSize, maxSize, stepSize) {
    numScoops = round((maxSize-minSize)/stepSize);
    // echo("Creating ", numScoops+1, " scoops");
    loops = [0:numScoops];
    for(i=loops) {
        size = minSize + i*stepSize;
        translate([i * 3, 0, 0]) createScoop(size);
    }
}

module createScoop(cc) {
    // lets compute the size of the cavity
    radius = radiusForCC(cc);
    height = heightForCC(cc, radius);
    // echo(radius, height);

    union() {
        createCup(radius, height);

        // we want to have around 3.5 inch handles
        // not including the radius of the cup
        length = 3.5 * 2.54;
        createHandle(cc, length, radius, [0, 0, height/2]);
    }
}

module createHandle(cc, length, radius, offset) {
    // shaft
    difference() {
        translate(offset) rotate([90,0,0]) cylinder(d=HANDLE_DIAMETER, h=length);
        cylinder(r = radius, h=length*2, center=true);
    }

    // grip
    union() {
        translate([0,-length/2,0]) translate(offset) rotate([90,0,0])
        difference() {
            hull() {
                // translate([0,0,0]) sphere(d=HANDLE_DIAMETER);
                // translate([HANDLE_DIAMETER/2,0,length/2]) sphere(d=HANDLE_DIAMETER);
                // translate([-HANDLE_DIAMETER/2,0,length/2]) sphere(d=HANDLE_DIAMETER);
                // translate([0,-0.1,length/2]) sphere(d=HANDLE_DIAMETER);
                translate([0,0,0]) sphere(d=GRIP_DIAMETER);
                translate([0,0,length/2]) sphere(d=GRIP_DIAMETER);
            }
            translate([-GRIP_DIAMETER/2, HANDLE_DIAMETER/2,-HANDLE_DIAMETER]) cube(size=length);
        }

        for(strCC = str(cc, floor(cc) == ceil(cc) ? ".0" : "", " cc")) {
            // echo(str("Creating ", strCC, " scoop"));
            translate([0,-(length*.99),0.08]) translate(offset)
            rotate([0,0,270])
            linear_extrude(height = HANDLE_DIAMETER/2) {
               text(text = strCC, font = "Liberation Sans:style=Bold", size = HANDLE_DIAMETER, valign="center", halign = "right");
            }
        }
    }
}

module createCup(radius, height) {

    // hv + cv = cc or...
    // cc = 2/3 * π * r^3 + π * r^2 * h
    difference() {
        // cup
        union() {
            sphere(r = radius + CUP_WALL_SIZE);
            cylinder(r = radius + CUP_WALL_SIZE, h=height);
        }

        // cavity
        sphere(r = radius);
        cylinder(r=radius, h=height + 2);
    }
}

module createLeeSet() {
    createScoop(0.17);
    translate([0, -15, 0]) createScoops(0.3, 0.7, 0.2);
    translate([0, -30, 0]) createScoops(1.0, 4.3, 0.3);
}

module createSuperSet() {
    for(i=[0:4]) {
        translate([0, -15 * i, 0])
        createScoops(i+0.1, i+1.0, 0.1);
    }
}

requestedSet = "";
strSet = str(requestedSet);

// both strings? do a set
if(requestedSet == strSet) {
    if(requestedSet == "lee") {
        createLeeSet();
    }
    else if(requestedSet == "super") {
        createSuperSet();
    }
}
// otherwise must be a float
else {
    createScoop(requestedSet);
}

createScoop(0.17);
//createLeeSet();
//createSuperSet();
```