[User]
Hey, I'm looking to generate a variety of fortresses, and I'd like some help building a parametric OpenSCAD model to do this. I really like the style and functionality of the "Fortress Generator v1" on Thingiverse (http://www.thingiverse.com/thing:1619044). It's a good starting point, but I need some more flexibility and customization, and I'd like to have that in a set of well-organized and clearly defined files that work together, if possible. I'm thinking multiple .scad files so the parts are clear and separated.

Here's a basic outline of the features I'd like to control:

**Overall Structure:**

*   **Base Shape:** I'd like to define the base of the fortress as a regular polygon with a variable number of sides. This should be a main parameter that affects the layout.
*   **Wall Height & Thickness:** The walls need adjustable height and thickness, of course. I think that's handled well in the original code.

**Towers and Turrets:**

*   **Tower Probability:** I need to be able to set a probability (between 0 and 1) for whether a corner of the base shape will have a tower.
*   **Tower Height & Width:** The towers should have independent parameters for their height and width and sides. I also want to be able to specify if these should be randomized to some extent or not.
*   **Turret Probability & Max Count:** Similar to towers, I need to define a probability for a tower to have turrets, as well as set a maximum number of turrets per tower.
*   **Turret Size:** I need to control the size of turrets relative to their parent tower in terms of height and width.
*   **Roof Types:** I want different roof types for towers and turrets, including pointed, flat, or a combination of flat and pointed. I want an option for dome-shaped roofs, too. I'd also like to add to this, maybe a crenellated roof option?
*  **Recursive turrets:** like in the original design, recursive turrets would be great to have, so that turrets can have turrets on them, etc.

**Decorations:**

*   **Windows:**  I'd like to have windows on the walls and towers, with parameters to control how many windows there are. I also would like control over the height of each floor which directly affects the height and position of the windows.  I would like to have the option to have square, arched, or slit-style windows.
*   **Roof Decorations:** I'd like the option to generate ring-like decorations on the roofs of towers and turrets, but be able to turn them off or adjust the frequency and spacing.
*   **Corbels:** I would like to add corbel decorations under turrets (and perhaps even along the walls). I'd like to be able to choose whether to enable these and adjust their geometry.
*   **Bricks:** An optional brick pattern on the walls would be great - this would require parameters for brick size, spacing, and depth, and the ability to turn it off as this is often computationally expensive, as noted in the original code.

**Other Features:**

*   **Gate:** I would like a gate structure in one of the wall sections (perhaps controlled in part by the number of sides).
*   **Random Seed:** I definitely need a random seed to be able to generate different variations.
*   **Symmetry:** I'd like to control whether turrets on turrets should be symmetrical or not.
*   **Partial Generation:** It would be really helpful to separate the structure and roofs into different STL files for rendering and assembly purposes.
*   **Clear File Structure:** I think having separate files for walls, towers, roofs, decorations, etc. would make the whole thing much easier to understand and expand on later.

I'm looking for a parametric, well-organized, modular structure with clean code. I am not concerned about speed or render time. The ability to have different submodules be separately controlled and enabled would be very helpful. If you could add parameters to control the general style of the fortress by using preset parameter combinations, that would be excellent. I'd like the code to be commented well and I would like some comments about possible next steps or improvements, where applicable. I don't have any specific libraries I want to use, but anything that would make this easier or more well-structured would be appreciated. Thanks!

[Assistant]
FortressGenerator_v1.scad:
```
/*----------------------------------------------------------------------------*/
/*  Fortress Generator v1                                                     */
/*  based on my previous Castle Generator at                                  */
/*    http://www.thingiverse.com/thing:1612651                                */
/*  Created by Ziv Botzer                                                     */
/*  zivbot@gmail.com                                                          */
/*  License: Creative Commons - Attribution - Non-Commercial - Share Alike    */
/*                                                                            */
/*  22.6.2016 First version on Thingiverse                                    */
/*----------------------------------------------------------------------------*/

// preview[view:south east, tilt:top diagonal]

// Master switch for details (windows, decorations...) - keep it off while you calibrate
generate_details = "No"; // [Yes, No]
// Variations - change it for a different results
random_seed = 42; // [1:1:400]
// Should each corner have a tower?
probability_of_towers = 1; // [0:0.1:1]
// Should a tower have turrets?
probability_of_turrets = 0.5; // [0:0.1:1]
// Maximum number of turrets per tower
max_number_of_turrets = 2;  // [0:1:5]
// Pointed roofs - tall or low?
roof_pointed_ratio = 1.8; // [0.4:0.2:4]

/* [Walls] */
wall_height = 35; // [10:1:140]
wall_diameter = 80; // [20:5:200]
wall_sides = 5; // [4,5,6,8,12,60,0:Random]
wall_thickness = 6; // [4:1:40]

/* [Towers and Turrets] */
// Height (without roof)  (0 = Random)
towers_height = 40;  // [0:1:150]
// Width  (0 = Random)
towers_width = 23; // [0:1:100]
// How many sides/facets for towers
towers_number_of_sides = 0; // [4,5,6,8,12,60,0:Random]
// Towers roof types
towers_roof_type = 0; // [1:Pointed,2:Flat,3:Flat+Point,0:Random]

// Turrets roof types
turrets_roof_type = 0; // [1:Pointed,2:Flat,3:Flat+Point,0:Random]

// Ratio of children turrets to parent (0.1 - very narrow, 0.9 - very wide)
turrets_width_ratio = 0.6; // [0.1:0.1:2]
// Ratio of children turrets to parent (0.1 - very narrow, 0.9 - very wide)
turrets_height_ratio = 0.7; // [0.1:0.1:2]

/* [Decorations] */
//
generate_windows = "Yes"; // [Yes, No]
// Rings, archers slots, etc.
generate_roof_decorations = "Yes"; // [Yes, No]
// Generate corbel decoration beneath turrets?
generate_corbels = "Yes"; // [Yes, No]
// (Extremely geometry intensive!! and not very effective when printing small)
generate_bricks = "No"; // [Yes, No]

/* [Decorations: Windows] */
// How many windows to scatter (1 = everywhere)
window_coverage = 0.15; // [0.02:0.02:1]
// Height of each floor (also determines gate structure)
floor_height = 3; // [1:0.5:20]
// Width of windows (default 2.5)
window_width_base = 1.2; // [1:0.1:10]

/* [Decorations: Bricks] */
// Height of the bricks
brick_height = 1.5; // [1:0.1:3]
// Width of the bricks
brick_horz = 4; // [1:0.5:20]
// Width of mortar between the bricks
brick_space = 0.2; // [0.2:0.1:2]
// Depth of spacing between the bricks !this is an overhang - keep it tiny!
brick_space_depth = 0.15; // [0.1:0.05:1]

/* [Partial Generation] */
// Use to separate STLs for rendering
what_to_generate = 1; // [1:Everything,3:Structures only,4:Roofs only]

/* [Hidden] */

// Symmetry for all other levels !Double complexity!
next_levels_symmetry = "No"; // [Yes, No]

// Flag poles are more likely to mess up the print than look nice, so they're permanently off
generate_flag_poles = "No"; // [Yes, No]

// More constants
sides_predef=[4,5,6,8,12,60]; // possible number of sides per polygon
$fn = 10; // Basic resolution (hardly affects anything, controlled locally)
overlap = 0.01; // used to make sure union/difference give nice results

roof_flat_extend_ratio = 0.5; // [0.1:0.1:1] // Flat roofs - how wide?
pointed_roof_cone_base_ratio = 0.04; // ratio between inverted base cone of roof, and the cone of roof
roof_deco_spacing_height = 0.25*floor_height; // distance between ring decorations on the roofs
edge_margin_factor = 0.1;

max_roof_types = 3; // 4 allows for dome roofs

// collection of booleans for easier handling
gen_roof_decorations = (generate_roof_decorations == "Yes") && (generate_details == "Yes");
gen_windows = (generate_windows == "Yes") && (generate_details == "Yes");
gen_flag_poles = (generate_flag_poles == "Yes") && (generate_details == "Yes");
gen_corbel_decoration = (generate_corbels == "Yes") && (generate_details == "Yes");
gen_bricks = (generate_bricks == "Yes") && (generate_details == "Yes");

gen_structure = ((what_to_generate == 1) || (what_to_generate == 3));
gen_roofs = ((what_to_generate == 1) || (what_to_generate == 4));

// uncomment to make every rebuild really random:
//random_seed = floor(rands(0,1000,1)[0]);
//echo(random_seed);

//include <fort_settings2.scad>;

//********************** MAIN *****************************

number_of_towers = (wall_sides <= 8)?wall_sides:8;

// walls
difference() {
    gate_width = 3*floor_height;
    gate_height = 5*floor_height;

    translate([0,0,-overlap])
    union() {
        difference() {
            // walls
            turret_round ( wall_diameter, wall_height, false, wall_sides, 1, 2 );

            // negative volume
            if (gen_structure)
            color("Gainsboro")
            translate([0,0,-overlap])
            linear_extrude(200)
            rotate([0,0,correction_angle(wall_sides)])
            circle(d=wall_diameter-2*wall_thickness, $fn=wall_sides);

        }

        // gate tower
        translate([0,-inradius( wall_diameter, wall_sides ) /2 ])
        union() {
            gate_tower_width = 3*gate_width;

            //translate([0,0,-overlap])
            turret_round ( gate_tower_width, 1.4*gate_height, false, 4, 1, 2 );

            //translate([0,0,-overlap])
            if (gen_structure)
            rotate([90,0,0])
            translate([0,gate_height/2,0])
            linear_extrude(inradius(gate_tower_width, 4)+2, center=true)
            special_rectangle(gate_width+3, gate_height+3);

        }

        // position towers around wall
        rotate([0,0,wall_sides==5?360/10:0])
        for (i = [0:number_of_towers-1])
            if (rands(0,1,1,random_seed+i*5)[0] <= probability_of_towers) {

            n_of_children = (rands(0,1,1,random_seed+i*3)[0] <= probability_of_turrets)?
                            floor(rands(1,max_number_of_turrets-0.01,1,random_seed+i*4)[0]) : 0;

            rotate([0,0,i*(360/number_of_towers) + 360/number_of_towers/2 ])
            translate([0,0.97*wall_diameter/2,0])
            rotate([0,0,wall_sides==4?45:0])
            turret_recursive(1, 2,
                            n_of_children,
                            (towers_width==0)?
                                rands(1.1,4.0,1,random_seed*(i+1))[0]*wall_thickness:towers_width,
                            (towers_height==0)?
                                rands(1.1,2,1,random_seed*(i+1))[0]*wall_height:towers_height,
                            true,
                            towers_number_of_sides,
                            random_seed+i*100 );
        }
    }

    // gate inner cut!
    if (gen_structure)
    color("Black")
    translate([0,0,-overlap])
    rotate([90,0,0])
    translate([0,gate_height/2,0])
    linear_extrude(500)
    special_rectangle(gate_width, gate_height);

    // trim everything below 0 Z
    if (gen_structure)
    translate([0,0,-50])
    cube([500, 500, 100], center=true);
}

/**************************************************************
   Helper functions
***************************************************************/
function decide_roof_type( t, rseed ) = (t==0)? floor(rands(0,max_roof_types-0.01,1,rseed)[0]+1) : t;

function decide_number_of_sides ( s, rseed ) = (s==0) ?
        sides_predef[ floor( rands(0,len(sides_predef)-0.01,1,rseed)[0] ) ] : s;

// the correction angle makes sure all polygons (no matter how many sides) align on one side
function correction_angle ( sides ) = (sides==4)?45: (sides==5)?18: (sides==8)?22.5: (sides==12)?15:0;

function decide_dimension ( dim, minimum, random_min, random_max, rseed ) =
     (dim == 0)? round(rands(random_min, random_max, 1, rseed)[0]) : (
     (dim >= minimum )? dim : minimum );

function inradius ( R, sides ) = R * cos( 180 / sides ); // inradius of the polygon shape

/**************************************************************
   Generate turrets with recursive children
***************************************************************/
module turret_recursive ( current_depth, max_recursion, number_children, w, h, main_tower, sides_, rseed ) {

    if (current_depth <= max_recursion)
    union() {

        // how many sides if this were a main tower
        sides = decide_number_of_sides (sides_, rseed+current_depth );

        // decide roof type
        main_tower_roof_type = decide_roof_type (towers_roof_type, rseed+current_depth);

        this_roof_type = (main_tower)? main_tower_roof_type :
            decide_roof_type (turrets_roof_type, rseed+current_depth );

        // GENERATE TOWER/TURRET
        turret_round(w, h, !main_tower, sides, roof_pointed_ratio, this_roof_type);

        inradius = w * cos( 180 / sides );

        if (number_children >= 1)
        for (i = [1:number_children]) {
            r1 = rands(-200,200,1,rseed + i*10 + current_depth*100)[0];
            v1 = inradius*0.55;  // y (offset from center) translation of children

            // calc width of children
            cw = w*turrets_width_ratio*turrets_width_ratio;
            t_width = (cw > 0.8*floor_height)?cw:0.8*floor_height; // set a minimum to turrets width

            t_height = h*turrets_height_ratio*turrets_height_ratio;

            z_transform = rands(2*t_width,1.0*h,1,rseed + i + current_depth)[0];

            rotate([0,0, r1 ] )
            translate([0,v1, z_transform])
            turret_recursive(current_depth+1, max_recursion, number_children, t_width, t_height, false, sides_, rseed*i );

            if (next_levels_symmetry=="Yes")
                rotate([0,0, 360-r1 ] )
                translate([0,v1, z_transform])
                turret_recursive(current_depth+1, max_recursion, number_children, t_width, t_height, false, sides_, rseed*i+10 );
        }
    }
}

/**************************************************************
   Generate a complete turret
***************************************************************/
module turret_round ( w, h, generate_bottom, sides, roof_ratio, roof_type_ ) {

    body_height = h;
    roof_height = w*roof_ratio;
    base_height = w*2;

    //rotate([0,0,(sides==4)?45:0])
    rotate([0,0,correction_angle(sides)])
    union() {

        // roof
        translate([0,0,body_height-overlap])
           turret_roof (w, roof_height, sides, roof_type_);

        // body of turret
        if(gen_structure)
        turret_body(w, body_height, sides);

        // under part
        if(gen_structure)
        translate([0,0,overlap])
        if (generate_bottom) {
            color("Gainsboro")
             turret_base(w, base_height, sides);
        }

    }
}

/**************************************************************
   Generate turret ROOF according to type
***************************************************************/
module turret_roof ( w, h, sides, rtype ) {

    union() {

        if (rtype == 1) {
            // pointed roof
            if (gen_roofs)
                roof_pointed ( w, h, sides );
        }
        else if (rtype == 2) {
            // flat roof
            if(gen_structure)
                roof_flat (w, 1.8*floor_height, sides);
        }
        else if (rtype == 3) {
            // flat and point
            if(gen_structure) {
                roof_flat (w, 1.8*floor_height, sides);
                translate([0,0,0.5*floor_height-overlap])
                    turret_body ( 0.7*w, 2*floor_height, sides );
            }
            if (gen_roofs)
                translate([0,0,1.5*floor_height + floor_height-2*overlap])
                roof_pointed ( 0.7*w, 0.8*h, sides );
        }
        else if (rtype == 4) {
            // Dome
            if(gen_structure) {
                roof_flat (w, 1.1*floor_height, sides);
                translate([0,0,0.5*floor_height-overlap])
                    turret_body ( 0.7*w, floor_height, sides );
            }
            if (gen_roofs)
                translate([0,0,0.5*floor_height + floor_height-2*overlap])
                roof_dome ( 0.7*w, 0.8*h, sides );
        }

    }
}

/**************************************************************
   Generate FLAT ROOF with decorations
***************************************************************/
module roof_flat ( w, h, sides ) {

    roof_bottom_part_height = 1.8*roof_flat_extend_ratio*floor_height;
    roof_top_part_height = h-roof_bottom_part_height;

    roof_top_width = w+1.8*roof_flat_extend_ratio*floor_height;
    roof_overhang = (roof_top_width - w);

    roof_scale = roof_top_width / w;

    shortest_radius = w * cos( 180 / sides ) / 2;
        // ^-- for polygons with low number of sides, gives the constrained radius

    circular_n = (sides <= 12)?sides:12;

    correct = correction_angle(sides);

    color("LightGrey")
    union() {
        translate([0,0,roof_bottom_part_height-overlap])
        difference()
        {
            // top part

            linear_extrude(roof_top_part_height)
            circle(d=roof_top_width,$fn=sides);

            // emboss center
            translate([0,0,0.3*roof_top_part_height])
            linear_extrude(roof_top_part_height)
            circle(d=w,$fn=sides);

            // cut archers slots
            translate([0,0,0.5*roof_top_part_height])
            pattern_around_polygon (roof_top_width, roof_top_part_height, sides,
                                0, 0,
                               element_max_width=floor_height,
                               element_height=roof_top_part_height,
                               extrude_length=5,
                               distribution_ratio=1 )
                square([0.4,1], center=true);
        }

        // base part with corbels
        difference() {
            linear_extrude(roof_bottom_part_height, scale=roof_scale)
             circle(d=w*1.0,$fn=sides);

            if (gen_corbel_decoration)
            translate([0,0,-0.1*roof_bottom_part_height])
            pattern_around_polygon (roof_top_width, roof_bottom_part_height, sides,
                                    2, 0,
                                    element_max_width=0.7*floor_height,
                                    element_height=roof_bottom_part_height,
                                    extrude_length=roof_overhang,
                                    distribution_ratio=1 )
                                    special_rectangle(0.6,1);
        }
    }
}

/**************************************************************
   Generate POINTED ROOF with decorations
***************************************************************/
module roof_pointed ( w, h, sides ) {

    roof_inverted_cone_height = h*pointed_roof_cone_base_ratio;
    roof_cone_height = h - roof_inverted_cone_height;

    roof_cone_base_width = w + 2*roof_inverted_cone_height;

    roof_tip_scale = (gen_flag_poles)?0.1:0.05;

    roof_cone_delta = roof_cone_base_width - roof_cone_base_width*roof_tip_scale;

    shortest_radius = w * cos( 180 / sides ) / 2;
        // ^-- for polygons with low number of sides, gives the constrained radius

    union() {
        // roof cone
        color("OrangeRed")
        translate([0,0,roof_inverted_cone_height-overlap])
          linear_extrude(roof_cone_height, scale=roof_tip_scale)
          circle(d = roof_cone_base_width, $fn=sides);

        // up-side-down cone below roof cone
        color("OrangeRed")
        linear_extrude(roof_inverted_cone_height, scale=roof_cone_base_width/w)
          circle(d = w, $fn=sides);

        // generate decos
       color("OrangeRed")
        if (gen_roof_decorations) {

            translate([0,0,roof_inverted_cone_height]) {

                // small roofs around base of roof
                default_size = window_width_base*1.5;
                s = (sides <= 12)?sides:12;
                mx = 0.7*roof_cone_base_width*3.14/s;

                deco_size = (default_size <= mx)?default_size:mx;

                translate([0,0,overlap])
                intersection() {
                    pattern_around_polygon ( 0.95*roof_cone_base_width,
                                    deco_size+0.1, sides,
                                    0.05*roof_cone_base_width,
                                    0, // vertical margin
                                    element_max_width=deco_size,
                                   element_height=deco_size,
                                   extrude_length=0.5*roof_cone_base_width,
                                   distribution_ratio=1 )
                        special_rectangle(0.8,1);

                    translate([0,0,-overlap])
                    linear_extrude(deco_size+1)
                    circle(d=roof_cone_base_width-overlap, $fn=sides);
                }

                // round horz rails along roof
                rail_spacing = 2*roof_deco_spacing_height;
                how_many_rows =  floor( roof_cone_height / rail_spacing);
                if (how_many_rows>1) {
                    rail_spacing2 = roof_cone_height / how_many_rows;
                    rail_height = 0.1*rail_spacing2;

                    color("Maroon")
                    for (i = [1:how_many_rows-1]) {
                        translate([0,0,i*rail_spacing2])
                            linear_extrude(rail_height)
                            circle(d = roof_cone_base_width-i*(roof_cone_delta/how_many_rows), $fn=sides);
                    }
                }

                // flag poles
                if (gen_flag_poles) {
                    translate([0,0,0.7*roof_cone_height]) {
                        color("DarkGoldenrod")
                        linear_extrude(0.3*roof_cone_height + 1.5*floor_height, scale=0.5)
                        circle(d=0.8, $fn=20);

                        /*
                        // actual flags are not printable without cursed supports...
                        color("White")
                        translate([0,-0.05,5])
                        cube([4,0.1,0.7]);
                        */
                    }
                }

            }
        }
    }

}

/**************************************************************
   Generate turret BODY with decorations
***************************************************************/
module turret_body ( w, h, sides ) {

    difference () {
        color("LightGrey")
        linear_extrude(h, convexity = 2) circle (d=w, $fn=sides);

        // _____Generate windows______
        color([0.3,0.3,0.3])
        if (gen_windows)
            pattern_around_polygon (w, h, sides,
                                    edge_margin_factor*w,
                                    edge_margin_factor*h,
                                    window_width_base,
                                    floor_height,
                                    0.2*w,
                                    window_coverage )
                scale([0.8,1/4,1])
                special_rectangle(0.8,3);

        // _____Generate brick pattern______
        color("DarkGray")
        if (gen_bricks) {

            how_many_rows =  floor( (h-brick_space) / (brick_height+brick_space));
            brick_height2 = (h-((how_many_rows-1)*brick_space)) / how_many_rows;

            how_many_cols = floor(w*3.1416/brick_horz);
            bricks_angle = 360/how_many_cols;

            difference () {

                union() {
                    // create the horizontal slots between the rows of bricks
                    for (i = [1: 1:how_many_rows-1] ) {
                        translate([0,0,i*(brick_height2+brick_space)-brick_space]) {
                                linear_extrude(brick_space,false) {
                                    circle(d = w*1.5, $fn=sides);
                            }
                        }
                    }

                    // create the vertical slots between the columns of bricks + random rotation
                    union()
                    for(vi = [0:how_many_rows-1]) {
                        rand_rotate = rands(0,1,1)[0];
                        translate([0,0,brick_height2/2+vi*(brick_height2+brick_space)])
                        for (i = [0: 1:(how_many_cols/2)-1] ) {
                            rotate([0,0,(i+rand_rotate)*bricks_angle])
                            color ("DimGray")
                            cube([brick_space, 1.1*w, brick_height2+0.2], center=true);
                        }
                    }

                }

                // substract middle volume
                translate([0,0,-0.5])
                linear_extrude(h+5) circle (d=w-brick_space_depth*2, $fn=sides);
            }
        }

    }

}

/**************************************************************
   Generate turret BASE with decorations
***************************************************************/
module turret_base ( w, h, sides ) {

    circular_n = (sides <= 6)?sides:6;
    shortest_radius = w * cos( 180 / sides ) / 2;

    correct = correction_angle(sides);

    color("Gainsboro")
    rotate([0,0,(sides==4)?-45:0]) // fix square alignment
    union () {
        // inverted cone
        translate([0,-w/2,0])
        rotate([180,0,0])
        linear_extrude(height = h, scale=0.1, convexity = 3)
        translate([0, -w/2, 0])
        rotate([0,0,(sides==4)?45:0]) // fix square alignment
         difference() {

             circle(d = w, $fn=sides);

             if (gen_corbel_decoration) {
                rotate([0,0,correct])
                for (i = [0:circular_n-1]){
                    d_ = 0.5*3.1416*w/circular_n;
                    rotate([0,0, i*(360/circular_n) ])
                    translate([0,1.1*shortest_radius,0])
                    circle(d=d_, $fn=sides*4);
                }
            }
         }

        if (gen_corbel_decoration) {
            translate([0,-w/4,0])
            rotate([180,0,0])
             linear_extrude(height = h/2, scale=0.1, convexity = 3)
             translate([0, -w/4, 0])
             rotate([0,0,(sides==4)?45:0])
             circle(d = w, $fn=sides);
         }

   }
}

/**************************************************************
   Generate rectangle with pointed 45deg tip (for windows and other decorations)
***************************************************************/
module special_rectangle (w, h) {
    // if h is too small its ignored
    // ^-- thats not good behaviour, leading to misalignment <<<<
    offs = sqrt(2*pow(w/2,2));
    rotate([180,0,0])
    translate([0,-h/2,0])
    union() {
        hull() {
            translate([0,offs/2,0])
            rotate([0,0,45])
            square(w/2,center=true);

            difference() {
                translate([0,offs,0])
                circle(d=w, $fn=20);

                // substract for half circle
                translate([0,offs+w/2,0])
                square([w*1.1,w],center=true);
            }
        }
        if (h > offs)
                translate([0,offs+(h-offs)/2,0])
                square([w,h-offs],center=true);
    }
}

/**************************************************************
   module for distributing elements along floors, sides and per each facet
***************************************************************/
module pattern_around_polygon (w, h, sides,
            width_padding, height_padding,
            element_max_width, element_height,
            extrude_length, distribution_ratio) {
// distribute child geometry along sides of defined polygon (w,h,sides)
// size of 2D element given should be 1X1 to completely fill the grid, or smaller for partial.

    h2 = h-height_padding;

    vertical_n = floor(h2/element_height); // how many rows of elements
    element_height2 = h2/vertical_n;

    // treat circular as (diameter/element_width) sided
    circular_n = (sides > 12)? floor(w*3.1415/(element_max_width)): sides;

    ww = w*sin(180/circular_n); // facet width calculated per circular_n
    element_width = (ww<element_max_width)?ww:element_max_width; // limit window width

    // for circular only one element per facet
    side_length = w*sin(180/sides)-width_padding;
    elements_per_facet = (sides <= 12) ?
                floor ( side_length / element_width ) : 1;

    element_width2 = (sides <= 12) ?
                side_length / elements_per_facet : element_width;

    inradius = w * cos( 180 / sides ); // inradius of the polygon shape

    delta_per_facet = 0.5*(elements_per_facet-1) * element_width2;

    rotate([0,0,correction_angle(sides)])
    for (a=[1:1:vertical_n]) // per each floor
    for (b=[0:1:circular_n]) {   // per each side
        for (c=[0:1:elements_per_facet-1]) // per each facet with multiple windows
        if (rands(0,1,1)[0] <= distribution_ratio)
        rotate([0,0,b*360/circular_n])
        translate([-delta_per_facet + c*element_width2,0,0])
        translate([0,inradius/2,(a-0.5)*(h2/vertical_n) + height_padding/2]) {
            union() {
                rotate([90,0,0]) {
                    linear_extrude(extrude_length,center=true)
                    scale([element_width2, element_height2])
                    children(0);
                }
            }
        }
    }
}

// And they lived happily ever after...

```


[User]
Hey, I'm looking to make a ring with a Zelda Triforce design, kind of like a bas-relief. I saw one online that was based on the Zeldathon event and I'd like to recreate it, but with a few variations. I need to be able to specify the ring size, the height of the ring, and the thickness of the base and the raised features.

Here are some specific requirements I have:

*   **Ring Size:** I need to be able to specify the US ring size, or, alternatively, the inner diameter of the ring in millimeters. I'd like to use the standard US ring size equation if the diameter isn't specified.
*   **Ring Height:** The height of the ring needs to be customizable.
*   **Thickness Control:** I need to specify the thinnest part of the base layer of the ring (basically the main ring band) and the thickness of the raised Triforce parts.
*   **Triforce Pattern:** I want the option to have either one set of Triforces around the ring or mirrored pairs of Triforces opposite each other. Also, I want the ability to set how many Triforce repetitions there are around the ring or have it calculate the number of repetitions automatically based on the ring size.
*   **Bas Relief vs. Floating Triforces:** I want the ability to switch between a bas-relief effect where the Triforce is raised from the base ring or have them "floating" (the base ring just provides support).

I'm looking for a parametric design, so I'd like to have all these options as customizable variables in an OpenSCAD file. I'd like the design to be relatively smooth, so the circle should be made up of many facets. Can you also echo the inner diameter?

I don't need any specific libraries like MCAD or BOSL. I'm hoping for a fairly straightforward OpenSCAD file, nothing too fancy.

[Assistant]
Zeldathon_Recovery_Triforce_Bas_Relief_Ring.scad:
```
// Zeldathon Recovery Triforce Bas Relief Ring (Customizable)
// by pikafoop (www.pikaworx.com)

/* [Basic Options] */

// : U.S. Ring Size (see Advanced Options to specify diameter in mm)
ring_size = 14; //[4:0.25:16]

/* [Advanced Options] */

// (mm)
ring_height = 9; //[5:0.25:20]

// (mm) : Override ring size and specify inner diameter; 0 means use ring size
ring_diameter = 0;

// (mm) : How thin can we print a base layer on your printer?
thinnest_layer = 0.8; //[0.8:0.1:2]

// (mm) : How much thicker should the thickest part of the ring be?
thickest_feature = 0.5; //[0.5:0.1:2]

// Pattern repitions. Leave a 0 to use the default for selected ring size.
pattern_repititions = 0;

/* [Hidden] */

// Do we want opposing triforces, or just one set?
opposing_triforces = 1; // [1:Opposing,0:One Set]

// Do we want a solid ring with bas relief triforces, or for the triforces to be "floating"?
bas_relief = 1; // [1:Bas Relief,0:Floating]

resolution = 120;

// if we don't override the ring size, calculate using https://en.wikipedia.org/wiki/Ring_size#Equations
inner_diameter = ring_diameter ? ring_diameter : 11.63 + 0.8128*ring_size;
echo(inner_diameter=inner_diameter);

// PARAMATER ALIASES
ring_base_width = thinnest_layer; //mm
ring_extrusion = thickest_feature; //mm

$fn = resolution;

tri_d = ring_height;

num_tf = pattern_repititions == 0 ? floor(3.14*inner_diameter / tri_d / 2 - 0.5) * 2 : pattern_repititions;

intersection() {
    difference() {
        cylinder( d=inner_diameter + thinnest_layer * 2 + thickest_feature*2, h=ring_height );
        translate([0,0,-1]) cylinder( d=inner_diameter, h=ring_height + 2 );
    }
    for( theta = [0 : 360 / num_tf : 359.9] ) {
        rotate([0,0,theta]) translate([0,0,ring_height/2]) rotate([90,0,0]) triforce( tri_d, inner_diameter/2 + thickest_feature*5 );
        if (opposing_triforces == 1) {
            rotate([0,0,theta+360/num_tf/2]) translate([0,0,ring_height/2]) rotate([180,0,0]) rotate([90,0,0]) triforce( tri_d, inner_diameter/2 + thickest_feature*5 );
        }
    }
}

difference() {
    union() {
        cylinder( d=inner_diameter + thinnest_layer * 2 + thickest_feature * 2, h=ring_height/20 );
        if (bas_relief == 1) {
            cylinder( d=inner_diameter + thinnest_layer * 2, h=ring_height );
        }
        translate([0,0,ring_height/20]) cylinder( d1=inner_diameter + thinnest_layer * 2 + thickest_feature * 2, d2=inner_diameter+thinnest_layer * 2, h=ring_height/10 );
        translate([0,0,17*ring_height/20]) cylinder( d2=inner_diameter + thinnest_layer * 2 + thickest_feature * 2, d1=inner_diameter+thinnest_layer * 2, h=ring_height/10 );
        translate([0,0,19*ring_height/20]) cylinder( d=inner_diameter + thinnest_layer * 2 + thickest_feature * 2, h=ring_height/20 );
    }
    translate([0,0,-1]) cylinder( d=inner_diameter, h=ring_height + 2 );
}

module triforce( d, h ) {
    translate([0, -d/8, 0]) rotate([0,0,-30]) difference() {
        cylinder( d = d, h = h, $fn = 3 );
        rotate([0,0,180]) translate([0,0,-1])
        cylinder( d = d/2.3, h=h+2, $fn = 3);
    }
}
```


[User]
I need an OpenSCAD design for a multi-port cable organizer, specifically for a MacBook Pro. It should be a rectangular block with channels to hold a MagSafe 2, Thunderbolt 1, Thunderbolt 2, and a USB connector.  It needs to be fully parametric so I can adjust dimensions for different cables and connectors.

Here's a breakdown of the requirements:

**Overall Shape:**

*   The main body is a rectangular block with rounded corners. The corners should be configurable.
*   The overall width should be calculated from the individual connector widths and offsets.
*   The overall height and thickness of the body should be adjustable as parameters.
*   It should be designed so that the finished piece is oriented correctly for printing without needing rotation, i.e. a flat rectangular block on the printing bed.

**Connector Channels:**

*   There should be separate channels for:
    *   MagSafe 2
    *   Thunderbolt 1
    *   Thunderbolt 2
    *   USB
*   Each channel should have:
    *   A width, height and depth parameter for the specific connector.
    *   A configurable fillet/rounding value for its corners.
*   The channels should be positioned based on offsets from each other. These offsets should be parameters.
* The depth of each channel should account for an endstop at the very end.

**Cable Stops and Endstops:**

*   Each channel needs an endstop at the back to prevent the connector from pulling out through the device end. These endstops should have parametric height, width and depth.
*   Each channel *except the MagSafe* needs a cable stop. These should be wedge-shaped to prevent cables from backing out, and these cable stops should be positioned a set distance from the back of the device, which should be adjustable. The cable stop should have its own depth, width and height parameters. The MagSafe channel will use the endstop itself to prevent backout, and thus does not require a cable stop.
* The cable channels should increase in height to accomodate for the cablestops, but the increase should be applied such that it only occurs when cable stops exist.
*   Cable stop depth may need to be trimmed if the overall channel depth would make the cablestop extend out past the body. The cablestop needs to be made to cut itself on the outer part of the body, while still maintaining its wedge shape.

**MagSafe 2 Specifics:**

* The magsafe channel needs an additional hole for the charging indicator light. The position and radius of this hole should be adjustable.
* The magsafe channel does not need a cable stop since the endstop will serve this purpose.

**Helper Discs:**

*   There should be an optional feature that adds small discs at the corners of the main body to help prevent warping when printing with ABS. It should be toggled on/off with a boolean variable.

**Other requirements:**

*   The design should be easy to print on a typical FDM printer.
*   The design must use the `roundedcube()` function from somewhere, likely from an existing library. Don't know which one, but it should be available.
* I would like it to use the `hull()` and `rotate()` operations already available in OpenSCAD.
*   I'd like to use the `atan()` function as well for the angle on the wedge-shaped cablestops.
* The code should output echo statements with the actual dimensions of the channels so I can confirm all my math is correct.

I am expecting a functional OpenSCAD file or files that I can load up and customize. The files shouldn't rely on any special libraries beyond the `roundedcube()` function, or the built-in functions mentioned above.

[Assistant]
JimConnect.scad:
```
// Original concept and design by biludavis http://www.thingiverse.com/thing:202491
// Parametricly recreated in OpenSCAD by Jim Shank
// 2016-07-27   -Initial release in SCAD
// 2016-08-01   -Broke out variables into customizer friendly sections
// 2016-08-04   -Refactored repeatable code into modules
//              -Converted cable stops to wedges (used atan(), very fancy)
// 2016-08-17   -Fixed Magsafe2 cable stop positioning and size calculations
// 2016-08-29   -Added logic to adjust the cable channel height based on cablestop existence
//              -Getting away from camelCase in favor of underscore_seperation

//use <ruler.scad>
// preview[view:north west, tilt:top]

/* [Settings] */
// If you are having problems with ABS curling
add_helper_discs = "no"; //[yes:Add Helper Discs,no:No Helper Discs]
// Magsafe 2 dimensions

magsafe_width = 17.15;
magsafe_height = 5.85;
magsafe_depth = 10.8;

// Thunderbolt 1 dimensions

tb1_width = 10.85;
tb1_height = 7.95;
tb1_depth = 16;

// Thunderbolt 2 dimensions

tb2_width = 11.7;
tb2_height = 8.5;
tb2_depth = 17.5;

// USB dimensions

usb_width = 15.44;
usb_height = 8.1;
usb_depth = 20;

//%ruler(length = 30); //, t=[tb1_center+cablestop_width/2,body_thickness/2,-(tb1_height/2)], r=[0,0,180]);

/* [Cable Stops (Advanced)] */

tb1_fillet = 1.5;
tb1_endstop_depth = 0.5;
tb1_endstop_height = 0.9;

tb2_fillet = 1.5;
tb2_endstop_depth = 0.5;
tb2_endstop_height = 0.9;

usb_fillet = 0.2;
usb_endstop_depth = 0.5;
usb_endstop_height = 0.9;

magsafe_fillet = 2;
magsafe_endstop_depth = 0.2;
magsafe_endstop_height = 0.7;

magsafe_light_hole_offset = 5.3;
magsafe_light_hole_radius = 1.5;
// Endstops are small stoppers at the end of the connector channel
// that keep the cable from pulling through

endstop_depth = 0.5;
endstop_width = 6;
endstop_height = 0.2;
// Cable stops keep the cable from backing out

cablestop_width = 4;
cablestop_depth = 2.25;
cablestop_height = 0.4;
cablestop_clearance = 0.1;

/* [Port Offsets (Advanced)] */
magsafe_to_tb1_offset = 18.12;
tb1_to_tb2_offset = 14;
tb2_to_usb_offset = 15.9;

/* [Hidden] */
// Connector holder body settings
body_height = 12; //default 12
body_thickness = 18.5;
side_thickness = 3; //default 3
body_fillet = 1.5;

// Adjust this to 0.01 to preview correctly in OpenSCAD
render_fix = 0.01;

// Width of the connector body is a sum of all of the connector offsets + the side thicknesses
body_width = side_thickness+(magsafe_width/2)+magsafe_to_tb1_offset+tb1_to_tb2_offset+tb2_to_usb_offset+(usb_width/2)+side_thickness;
magsafe_center = -(body_width/2 - side_thickness-magsafe_width/2);
tb1_center = magsafe_center + magsafe_to_tb1_offset;
tb2_center = tb1_center + tb1_to_tb2_offset;
usb_center = tb2_center + tb2_to_usb_offset;

// Main Method
rotate([90,180,0]) { // Align for printing
    translate([0,-(body_thickness/2),0]) {
        body();
        endstops();
        cablestops();
        if (add_helper_discs == "yes") {
            // upper left
            draw_helper_discs();
            // lower left
            mirror([1,0,0]) {
                draw_helper_discs();
            }
            // upper right
            mirror([0,0,1]) {
                draw_helper_discs();
            }
            // lower right
            mirror([1,0,0]) {
                mirror([0,0,1]) {
                    draw_helper_discs();
                }
            }
        }
    }
}
module body() { // Main body with cable head channels
    difference() {
        // Draw the connector body
        roundedcube([body_width,body_thickness,body_height], radius = body_fillet, apply_to = "y", center = true);
        // Offset magsafe hole
        translate([magsafe_center,0,0]) {
        // Draw magsafe connector
            echo("Actual magsafe dimentions W:", magsafe_width, " D:", body_thickness + render_fix, " H:", magsafe_height);
           roundedcube([magsafe_width,body_thickness + render_fix,magsafe_height],radius = magsafe_fillet, apply_to = "y", center = true);
        }
        //Magsafe charging indicator light hole
        translate([magsafe_center,body_thickness/2-magsafe_light_hole_offset,magsafe_height/2+(body_height/2-magsafe_height/2)/2]) {
           cylinder(h=body_height/2-magsafe_height/2+render_fix,r1=magsafe_light_hole_radius, r2=magsafe_light_hole_radius, center = true, $fn=30);
        }
        // TB1 connector channel
        draw_cable_channel(tb1_center, tb1_width, tb1_height, tb1_depth, tb1_fillet, "TB1");
        // TB2 connector channel
        draw_cable_channel(tb2_center, tb2_width, tb2_height, tb2_depth, tb2_fillet, "TB2");
        // USB connector channel
        draw_cable_channel(usb_center, usb_width, usb_height, usb_depth, usb_fillet, "USB");
        // Grips
        draw_grip(); // right grip
        mirror(1,0,0) {
            draw_grip(); // left grip
        }
    }
}

module endstops() { //End stops keep the cable from coming out the Macbook end
    color("blue") {
        // Magsafe Endstop - This one is special since we don't increase the cable height to accomidate the cable stop
        translate([magsafe_center,body_thickness/2 - magsafe_endstop_depth/2,-(magsafe_height/2-magsafe_endstop_height/2)]) {
            cube([magsafe_width, magsafe_endstop_depth, magsafe_endstop_height], center = true);
        }
        // TB1 Endstop
        draw_endstop(tb1_center, tb1_endstop_height, tb1_endstop_depth, tb1_height, tb1_width);
        // TB2 Endstop
        draw_endstop(tb2_center, tb2_endstop_height, tb2_endstop_depth, tb2_height, tb2_width);
        // USB Endstop
        draw_endstop(usb_center, usb_endstop_height, usb_endstop_depth, usb_height, usb_width);
    }
}
module cablestops() {// Cable stops in the middle to keep the cable from backing out
    color("green") {
        // Magsafe2 Cable Stop
        translate([magsafe_center,body_thickness/2-magsafe_endstop_depth-magsafe_depth-cablestop_depth/2,-(magsafe_height/2)+cablestop_height/2]) {
            difference() {
                cube([cablestop_width, cablestop_depth, cablestop_height], center = true);
                translate([0,0,cablestop_height/2 + .2]) rotate([atan(cablestop_height/(cablestop_depth)),0,0]) cube([cablestop_width + render_fix, cablestop_depth + 1, cablestop_height + .4], center = true);
            }
        }
        // TB1 Cable Stop
        draw_cablestop(tb1_center, tb1_endstop_depth, tb1_height, tb1_depth);
        // TB2 Cable Stop
        draw_cablestop(tb2_center, tb2_endstop_depth, tb2_height, tb2_depth);
        // USB Cable Stop
        draw_cablestop(usb_center, usb_endstop_depth, usb_height, usb_depth);
    }
}
// Helper Modules
module draw_helper_discs() { // Corner discs for ABS prints that tend to lift at the edges
    translate([body_width/2,body_thickness/2-.1,body_height/2]) {
        rotate([90,0,0]) {
            cylinder(h=0.2,r1=3, r2=3, center = true, $fn=30);
        }
    }
}
module draw_cable_channel(channel_center, cable_width, cable_height, cable_depth, cable_fillet, cable_name) {
    //TODO - Logic to size connector height based on cablestop presense
    channel_depth = endstop_depth+cable_depth;

    //Offset hole
    translate([channel_center,0,0]) {
        // Draw connector channel
        if ( body_thickness >= channel_depth) {
        // increase the height of the channel to accommodate the cablestop
            echo("Actual ", cable_name, " dimentions W:", cable_width, " D: ", body_thickness + render_fix, " H: ", cable_height+cablestop_height-cablestop_clearance);
            roundedcube([cable_width,body_thickness + render_fix,cable_height+cablestop_height-cablestop_clearance],radius = cable_fillet, apply_to = "y",center = true);
        }
        else {
            // don't increase the height of the channel to accommodate the cablestop
             echo("Actual ", cable_name, " dimentions W:", cable_width, " D: ", body_thickness + render_fix, " H: ", cable_height);
            roundedcube([cable_width,body_thickness + render_fix,cable_height],radius = cable_fillet, apply_to = "y",center = true);
        }
    }
}
module draw_endstop(center, endstop_height, endstop_depth, connectorHeight, connectorWidth) {
    translate([center,body_thickness/2 - endstop_depth/2,-(connectorHeight/2)+endstop_height/2-cablestop_height/2]) {
            cube([connectorWidth, endstop_depth, endstop_height], center = true);
    }
}

module draw_cablestop(center, endstop_depth, connectorHeight, connectorDepth ) {
    cablestop_offset = endstop_depth+connectorDepth+cablestop_depth;
        // Trim the depth of the cablestop if it would overhang the connector body
        if (cablestop_offset - body_thickness > 0) {
            cablestopOffset = cablestop_offset - body_thickness;
            translate([center,body_thickness/2-endstop_depth-connectorDepth-cablestop_depth/2+cablestopOffset/2,-(connectorHeight/2)+cablestop_clearance/2]) {
                difference() {
                    cube([cablestop_width, cablestop_depth-cablestopOffset, cablestop_height], center=true);
                    translate([0,0,cablestop_height/2]) rotate([atan(cablestop_height/(cablestop_depth-cablestopOffset)),0,0]) cube([cablestop_width + render_fix, cablestop_depth, cablestop_height], center=true);
                }
            }
        }
        else { // if there is no overhang
            translate([center,body_thickness/2-endstop_depth-connectorDepth-cablestop_depth/2,-(connectorHeight/2)+cablestop_clearance/2]) {
                difference() {
                    cube([cablestop_width, cablestop_depth, cablestop_height], center=true);
                    translate([0,0,cablestop_height/2]) rotate([atan(cablestop_height/(cablestop_depth)),0,0]) cube([cablestop_width+render_fix, cablestop_depth+1, cablestop_height], center=true);
                }
            }

        }
}

module draw_grip() {
    hull() {
            translate([body_width/2,0,0])
                cube([.5,8,7], center = true);
            translate([body_width/2-1,0,0])
                cube([.5,7,6], center = true);
    }
}
module roundedcube(size = [1, 1, 1], center = false, radius = 0.5, apply_to = "all") { //roundedcube by Daniel Upshaw https://danielupshaw.com/openscad-rounded-corners/
    $fs = 0.01;
	// If single value, convert to [x, y, z] vector
	size = (size[0] == undef) ? [size, size, size] : size;

	translate_min = radius;
	translate_xmax = size[0] - radius;
	translate_ymax = size[1] - radius;
	translate_zmax = size[2] - radius;

	diameter = radius * 2;

	module build_point(type = "sphere", rotate = [0, 0, 0]) {
		if (type == "sphere") {
			sphere(r = radius);
		} else if (type == "cylinder") {
			rotate(a = rotate)
			cylinder(h = diameter, r = radius, center = true);
		}
	}

	obj_translate = (center == false) ?
		[0, 0, 0] : [
			-(size[0] / 2),
			-(size[1] / 2),
			-(size[2] / 2)
		];

	translate(v = obj_translate) {
		hull() {
			for (translate_x = [translate_min, translate_xmax]) {
				x_at = (translate_x == translate_min) ? "min" : "max";
				for (translate_y = [translate_min, translate_ymax]) {
					y_at = (translate_y == translate_min) ? "min" : "max";
					for (translate_z = [translate_min, translate_zmax]) {
						z_at = (translate_z == translate_min) ? "min" : "max";

						translate(v = [translate_x, translate_y, translate_z])
						if (
							(apply_to == "all") ||
							(apply_to == "xmin" && x_at == "min") || (apply_to == "xmax" && x_at == "max") ||
							(apply_to == "ymin" && y_at == "min") || (apply_to == "ymax" && y_at == "max") ||
							(apply_to == "zmin" && z_at == "min") || (apply_to == "zmax" && z_at == "max")
						) {
							build_point("sphere");
						} else {
							rotate =
								(apply_to == "xmin" || apply_to == "xmax" || apply_to == "x") ? [0, 90, 0] : (
								(apply_to == "ymin" || apply_to == "ymax" || apply_to == "y") ? [90, 90, 0] :
								[0, 0, 0]
							);
							build_point("cylinder", rotate);
						}
					}
				}
			}
		}
	}
}

```


[User]
I'm looking for a self-watering planter design, and I've got a pretty good idea of what I want. I'd like it to be a two-part design, consisting of a reservoir and a pot. The reservoir will hold the water, and the pot will sit on top of it, holding the plant and soil.

Both the reservoir and the pot should be based on regular polygons. I want to be able to customize the number of sides, so it could be anything from a square to a circle. Also, I'd like to be able to adjust the radius and height of the planter. The radius should be between 25 and 75 units, and the height between 25 and 150 units. The thickness of the walls should also be adjustable, with options for 3, 5, or 7 units.

The reservoir should have a solid bottom that's thicker than the walls. The reservoir also needs a water conduct feature, located near the edge. The conduct should be a polygonal cylinder with a hole that goes down to the bottom of the reservoir. It should have a diagonal notch cut into it to allow water to flow in from the side. The conduct radius should be 25% of the overall radius, and the conduct height should be calculated such that it's slightly taller than the pot will be.

The pot should fit snugly on top of the reservoir. It should have a head, a middle section, and a tapered bottom. The head should be a simple polygonal cylinder, and the middle section should be a slightly smaller polygonal cylinder. The bottom section should be a truncated polygonal cone that tapers down to a smaller radius. It is very important that the middle section of the pot has some holes in it to allow water to seep in from the reservoir. The number of holes should match the number of sides, up to a maximum of 8 holes. The holes should be circular and positioned around the middle section.

Finally, the pot should have a small cylindrical feature that fits into the water conduct in the reservoir, acting as a wick to draw water up into the soil.

Could you help me design a parametric OpenSCAD file (using the `build_plate.scad` file from the `utils` directory of the NopSCADlib library) that can generate both parts of this planter? I'd like to be able to customize all the parameters I mentioned, and it would be great if the script could generate both parts separately or together. There should also be an option to display the reservoir and pot stacked on top of each other for visualization, with the pot offset vertically so that it's floating above the reservoir.

[Assistant]
autoWateringPlanter-2016-06-29.scad:
```
use <utils/build_plate.scad>

// variable description
//Which one would you like to see?
part = "both"; // [reservoir:Reservoir Only,pot:Pot Only,both:Reservoir and Pot,view:Reservoir and Pot only for display]
radius = 35; // [25:5:75]
height = 50; // [25:5:150]
thickness = 3; //[3,5,7]
sides_number = 8; // [4,6,8,12,20]

// variables used by the script
gap = 0.1*1;
clearance_factor = 0.1*1;
radius_inner=radius-thickness;
bottom_thickness = thickness*1.5;
pot_head_height = height*0.10;
conduct_radius = radius*0.25;
conduct_height = height-bottom_thickness+pot_head_height*1;
offset_view=height*1;
holes_number=sides_number;
max_holes_number=8*1;

//Display the build plate, It doesn't contribute to final object
build_plate_selector = 3*1;
build_plate_manual_x = 200*1;
build_plate_manual_y = 200*1;
build_plate(build_plate_selector,build_plate_manual_x,build_plate_manual_y);

//preview[view:south east, tilt:top diagonal]

module water_conduct(boring) {
  if (boring == true) {
    difference() {
      cylinder(r=conduct_radius,h=conduct_height,$fn=sides_number);
      translate([0,0,-gap])
        cylinder(r=conduct_radius-thickness/2,h=conduct_height+gap*2,
        $fn=sides_number);
      translate([-conduct_radius,0,-gap])
      rotate([0,45,0])
        cube(conduct_radius*2.5,center=true);
    }
  }
  else {
    cylinder(r=conduct_radius,h=conduct_height,$fn=sides_number);
  }
}

module reservoir() {
  color("Orange") {
    difference() {
      cylinder(r=radius,h=height,$fn=sides_number);
      translate([0,0,bottom_thickness])
        cylinder(r=radius_inner,h=height-bottom_thickness+gap*2,$fn=sides_number);
    }
    intersection() {
    translate([radius-conduct_radius,0,bottom_thickness])
        water_conduct(boring=true);
      cylinder(r=radius-thickness,h=conduct_height+bottom_thickness,$fn=sides_number);
    }
  }
}

module pot_body (boring) {
  pot_radius_1 = radius;
  pot_radius_2 = radius - thickness - clearance_factor*5;
  pot_radius_3 = radius*0.2;

  pot_height_1 = pot_head_height;
  pot_height_2 = (height-bottom_thickness) * 0.15;
  pot_height_3 = (height-bottom_thickness) * 0.75;

  if (boring == true) {
    rotate([180,0,90])
    translate([0,0,-height-pot_height_1]) {
      difference() {
        color("red")
        cylinder(r=pot_radius_1,h=pot_height_1,$fn=sides_number);
        translate([0,0,-gap])
        cylinder(r=pot_radius_2-thickness,h=pot_height_1+2*gap,$fn=sides_number);
      }
      translate([0,0,pot_height_1])
      difference() {
        color("blue")
        cylinder(r=pot_radius_2,h=pot_height_2,$fn=sides_number);
        translate([0,0,-gap])
        cylinder(r=pot_radius_2-thickness,h=pot_height_2+2*gap,$fn=sides_number);
      }
      translate([0,0,pot_height_1+pot_height_2-gap*0.1])
      difference() {
        color("gold")
        cylinder(r1=pot_radius_2,r2=pot_radius_3,h=pot_height_3,$fn=sides_number);
        translate([0,0,-gap])
        cylinder(r1=pot_radius_2-thickness,r2=pot_radius_3,
              h=pot_height_3+2*gap-thickness,$fn=sides_number);
        if(holes_number<=6) {
          for(i=[1:1:holes_number-1])
            rotate([0,0,i*360/holes_number])
            translate([0,(pot_radius_2+pot_radius_3)/1.75-thickness,pot_height_3/2])
              cylinder(r=radius*0.075,h=thickness*4,$fn=holes_number,center=true);
          }
        else {
          for(i=[1:1:max_holes_number-1]){
            rotate([90,0,i*360/max_holes_number-180])
            translate([0,(pot_radius_2+pot_radius_3)/1.75-thickness,pot_height_3/2])
              cylinder(r=radius*0.075,h=thickness*8,$fn=holes_number,center=true);
          }
        }
      }
    }
  }
  else {
    rotate([180,0,90])
    translate([0,0,-height-pot_height_1]) {
        color("red")
        cylinder(r=pot_radius_1,h=pot_height_1,$fn=sides_number);
      translate([0,0,pot_height_1])
        color("blue")
        cylinder(r=pot_radius_2,h=pot_height_2,$fn=sides_number);
      translate([0,0,pot_height_1+pot_height_2-gap*0.1])
        color("gold")
        cylinder(r1=pot_radius_2,r2=pot_radius_3,h=pot_height_3,$fn=sides_number);
    }
  }
}

module pot () {
  difference() {
    pot_body(boring=true);
    translate([radius-conduct_radius-gap*5,0,bottom_thickness+gap])
      scale([1.1,1.1,1])
        water_conduct(boring=false);
  }
  intersection() {
    pot_body(boring=false);
    translate([radius-conduct_radius-gap*1,0,bottom_thickness+gap*1])
      scale([1.35,1.35,1])
        water_conduct(boring=true);
  }
}

module reservoir_stl(){
  reservoir();
}

module pot_stl(){
  rotate([180,0,0])
  translate([0,0,-height-pot_head_height])
    pot();
}

// Generate the reservoir and pot for print
module print_part() {
  if (part == "reservoir") {
    reservoir_stl();
  } else if (part == "pot") {
    pot_stl();
  } else if (part == "both") {
    translate([-radius*1.25,0,0])
      reservoir_stl();
    translate([radius*1.25,0,0])
      pot_stl();
  } else if (part == "view") {
    reservoir();
    translate([0,0,offset_view])
      pot();
  } else {
    translate([-radius*1.25,0,0])
      reservoir_stl();
    translate([radius*1.25,0,0])
      pot_stl();
  }
}

print_part();

```


[User]
I want to create a cool-looking parametric design in OpenSCAD that I'm calling "Twisted Strands". The basic idea is to have multiple strands that twist around a central axis. Each strand should have a customizable radius and the ability to be stretched to create an oval cross-section. I'd also like to be able to rotate the strands individually.

The main parameters I envision are:

*   **Height:** The overall height of the model (e.g., 60mm).
*   **Number of Twists:** How many half-rotations (180 degrees) each strand makes along the height.
*   **Strand Options:** Different configurations for the strands, like single, double, mirrored, or double mirrored.
*   **Strand Radius:** The radius of each individual strand.
*   **Strand Stretch:** A scaling factor to make the strands oval-shaped.
*   **Strand Rotation:** An initial rotation for each strand.
*   **Resolution:** The number of facets for the circular shapes.
*   **Slices:** The number of slices along the height for the twisting effect.

Additionally, I want to be able to arrange these twisted strands in different configurations:

1. **X Group:** A set of strands arranged radially around the central axis. I want to control the number of strands, their distance from the center (radius), and an initial rotation angle for the group. There should also be an option to include a central strand or a copy of the Y group at the center.
2. **Y Group:** Similar to the X group, but with a different radius and potentially including a center strand.
3. **Z Group:** Another set of strands, but these would be the primary twisted strands. I want to control the number of strands, the radius of their twist, and their initial rotation angle.

Finally, I'd like to have an option to visualize a build plate during the design process, with different presets for common 3D printers (Replicator 2, Replicator, Thingomatic) and an option for manual dimensions.

For the code, I'd appreciate it if you could use the `build_plate.scad` utility for the build plate visualization. Please provide a complete OpenSCAD file that allows me to customize all these parameters and generate the "Twisted Strands" design.

[Assistant]
twisted_strands_v2.scad:
```
//
// Customizable Twisted Strands v2
// version 1.0   7/3/2016
// by Steve Van Ausdall
// (DaoZenCiaoYen @ Thingiverse)
//

// preview[view:south, tilt:top diagonal]

/* [Main] */
// in mm
height = 60 ; // [20:5:200]
// each twist is 180 degrees
num_twists = 2 ; // [1:4]
// where "include center" is true
center_rotation = 0 ; // [-90:90]
// strand options
strand_options = 2 ; // [0:Single,1:Double,2:Mirrored,3:Double Mirrored]
// radius of individual strands
strand_radius = 2 ; // [1.5:0.25:10]
// stretch results in oval strand cross sections
strand_stretch = 1.4 ; // [1:0.1:5]
// initial rotation of individual strands
strand_rotation = 45 ; // [-90:90]
// facets per shape
resolution = 24 ; // [4:2:64]
// slices per shape
slices = 24 ; // [4:2:64]
// color (preview only)
model_color = 8 ; // [0:Black,1:White,2:Grey,3:Red,4:DarkRed,5:Orange,6:SaddleBrown,7:Goldenrod,8:Gold,9:Yellow,10:GreenYellow,11:Green,12:DarkGreen,13:DodgerBlue,14:Blue,15:MediumBlue,16:DarkBlue,17:Indigo,18:Violet]

// Number of inner spokes (X)
num_x = 3 ; // [1:12]
// include center shape
include_center_x = 0 ; // [0:False,1:Copy Y,2:True,3:True and Copy Y]
// x radius  / distance
x_radius = 6 ; // [0:30]
// initial angle of model
x_angle = 0 ; // [-90:90]

// number of outer spokes (Y)
num_y = 3 ; // [1:12]
// include center of each Y shape
include_center_y = 0 ; // [0:False,1:True]
// y radius / distance
y_radius = 12 ; // [-20:30]
// initial angle of y groups
y_angle = 0 ; // [-90:90]

// number of strands per origin (Z)
num_z = 2 ; // [1:12]
// radius of individual strand twists (in mm)
z_radius = 8 ; // [0:30]
// initial angle of z groups
z_angle = 0 ; // [-90:90]

/* [Build Plate] */
// set to True to see the shape on your build plate
show_build_plate = 0 ; // [0:False,1:True]
// for display only, doesn't contribute to final object
build_plate_selector = 2 ; // [0:Replicator 2,1:Replicator,2:Thingomatic,3:Manual]
// Build plate x dimension for "Manual" (in mm)
build_plate_manual_x = 100 ; // [50:5:500]
// Build plate y dimension for "Manual" (in mm)
build_plate_manual_y = 100 ; // [50:5:500]

/* [Hidden] */

use <utils/build_plate.scad> ;

$fn = resolution ;
colors=[
  "Black", // 0
  "White", // 1
  "Grey", // 2
  "Red", // 3
  "DarkRed", // 4
  "Orange", // 5
  "SaddleBrown", // 6
  "Goldenrod", // 7
  "Gold", // 8
  "Yellow", // 9
  "GreenYellow", // 10
  "Green", // 11
  "DarkGreen", // 12
  "DodgerBlue", // 13
  "Blue", // 14
  "MediumBlue", // 15
  "DarkBlue", // 16
  "Indigo", // 17
  "Violet" // 18
];

main();

module main()
{
  color(colors[model_color])
  shape();
}

module shape()
{
  rotate([0,0,x_angle])
  radial_copy(num_x, x_radius, include_center_x)
  rotate([0,0,y_angle])
  radial_copy(num_y, y_radius, include_center_y)
  rotate([0,0,z_angle])
  z_group();
  if (include_center_x == 2 || include_center_x == 3) {
    rotate([0,0,center_rotation])
    z_group();
  }
}

module z_group()
{
  for (i = [0 : 360/num_z : 359])
  {
    strand(num_twists,i);
    if (strand_options == 1 || strand_options == 3) {
      strand(num_twists,i+180);
    }
    if (strand_options == 2 || strand_options == 3) {
      strand(-num_twists,i);
    }
    if (strand_options == 3) {
      strand(-num_twists,i+180);
    }
  }
}

module strand(t,i)
{
  rotate([0,0,i])
  translate([-z_radius,0,0])
  linear_extrude(
    height = height,
    center = false,
    convexity = 10,
    twist = t*180,
    slices = slices)
  translate([z_radius, 0, 0])
  base_shape();
}

module base_shape()
{
  rotate([0,0,strand_rotation])
  scale([strand_stretch,1,1])
  circle(r = strand_radius);
}

module radial_copy(copies,radius,include_center)
{
  if (copies > 1)
  {
    for (i = [0: 360/copies : 359])
    {
      rotate([0,0,i])
      translate([radius,0,0])
      children(0);
    }
  }

  if (copies == 1 || include_center == 1 || include_center == 3)
  {
    rotate([0,0,center_rotation])
    children(0);
  }
}

if (show_build_plate==1)
{
  build_plate(build_plate_selector,build_plate_manual_x,build_plate_manual_y);
}

```


[User]
I'm looking to create a pendant that displays a string of characters wrapped around a sphere, similar to the "PI Sphere" design. I need the design to be parametric in OpenSCAD.

Here are the key features and parameters I'd like to control:

*   **Characters:** The string of characters to display (e.g., "3.14159", "ABCDEF", etc.). This should be a string parameter.
*   **Symbol:** A special character or symbol to place at the bottom of the sphere (e.g., "π", a heart symbol).
*   **Sphere Radius:** The radius of the main sphere.
*   **Bottom Radius:** The radius of the circular base that the special symbol is placed on.
*   **Font Size:** The size of the text characters.
*   **Character Gap:** The vertical spacing between each character along the sphere's surface, measured in degrees.
*   **Floor Density:** A factor that controls how tightly the characters are wrapped around the sphere, influencing the character's vertical position.
*   **Begining Factor:** A degree value determining the starting angle of character placement.
*    **Thickness:** A value controlling the thickness of the character and lines.
*   **Chain:** The design should include a loop at the top for attaching a chain. This loop should also be parametric in size and position. A second loop for the connection to a chain link is also needed
*   **Font:** The font to use for the text characters should be a parameter for flexibility. I'd like to use "Arial Black" as the default, and "Broadway" as the font for the bottom symbol.

The characters should appear as if they are "wrapped" around the sphere, using rotations and translations. Each character should be extruded outwards from the sphere surface. There should also be a thin line segment extending out from the sphere, along with each of the characters, which may be a simple square. For decimal points, the characters should be lowered by one-third the font size, for aesthetic purposes.

I would like a single `.scad` file that defines these parameters, contains the modules to implement the design, and generates the final object.

Basically, I'm trying to recreate the "PI Sphere" pendant, but fully parametric, and with a couple of added touches, such as the lines and second loop. I am not using any libraries.

[Assistant]
text_pendant.scad:
```
chars = "3.14159265358979323846264338327950288419716939937510582097494459230781640628620899862803482534211706798214808651328230664709384460955058223172535940812848111745028410270193852110555964462294895493038196442881097566593344612847564823378678316527120190914564856692346034861045432664821339360726024914127372458700660631558817";
symbol = "π";
char_gap = 18;

module chars_sphere(chars, symbol, sphere_radius, bottom_radius, font_size, char_gap, floor_density, begining_factor, thickness) {
    b = sphere_radius * begining_factor;

    module chars() {
	    for(i = [0:(180 * floor_density - b) / char_gap]) {
			j = b + i * char_gap;
			rotate([0, 0, j ])
				rotate([0, -90 + j / floor_density, 0])

					translate([0, 0, chars[i] == "." ? -font_size / 3 : 0]) rotate([90, 0, 90])
					    linear_extrude(sphere_radius)
						    text(chars[i], valign = "center", halign = "center", size = font_size, font = "Arial Black");
		}
	}

	module line() {
	    step = 1;
		for(i = [0:(180 * floor_density - b) / step]) {
			j = b + i * step;
			rotate([0, 0, j ])
				rotate([0, -90 + j / floor_density, 0])
					 translate([0, 0, 0])
						rotate([90, 0, 90])
							linear_extrude(sphere_radius)
								translate([-font_size / 2, font_size / 2, 0]) square([0.5, thickness]);

		}
	}

	module pi() {
		linear_extrude(thickness * 15)
			circle(bottom_radius, center = true, $fn = 48);

		linear_extrude(thickness * 18)
			rotate(135) text(symbol, valign = "center", halign = "center", size = bottom_radius * 1.5, font = "Broadway");

	}

	chars();
    line();
	pi();
}

module text_pendant(chars, symbol) {
    radius = 20;
    sphere_radius = 20;
	bottom_radius = 8;
	font_size = 6;
	char_gap = 18;
	floor_density = 19;
	begining_factor = 38;

	s = radius / sphere_radius;

	scale([s, s, s / 3])
	    rotate(-135) chars_sphere(chars, symbol, sphere_radius, bottom_radius, font_size, char_gap, floor_density, begining_factor, 1 / s);

	// chain
	translate([0, 1, 0]) union() {
		translate([0, radius, 0]) rotate_extrude($fn = 96)
			translate([radius / 6, 0, 0])
				rotate([0, 0, 90])
					circle(radius / 20, $fn = 24);

		translate([0, radius * 1.2, 0])
			rotate([90, 90, 90])
				rotate_extrude($fn = 96)
					translate([radius / 6, 0, 0])
						rotate([0, 0, 90])
							circle(radius / 20, $fn = 24);
	}
}

text_pendant(chars, symbol, char_gap);

```


[User]
I need help designing a parametric PSU mounting bracket for 3D printing. I've seen a design I like, but it needs to be customizable for different PSU sizes. I want the design to be based on the style of the bracket from thingiverse.com/thing:1636876.

Specifically, the bracket should have a central piece that attaches to the frame, and two arms that extend out to mount to the PSU. There should be a small ridge or rill on the top of the frame-mount for added stiffness.

Here are the parameters I need to be able to control:

*   `psu_mount_hole_distance`: The distance between the mounting holes on the PSU.
*   `psu_mount_hole_d`: The diameter of the holes for the PSU mounting bolts.
*   `frame_mount_hole_d`: The diameter of the hole for mounting the bracket to the frame.
*   `extra_hole_d_tenth`: An extra diameter to add to the bolt holes (in tenths of a mm). I need this to compensate for slight variations and tolerances in printing and bolt size, so this should be added to the hole diameters. So, a value of 3 here should add 0.3mm to each hole diameter.
*   `middle_piece_width`: The width of the central piece that attaches to the frame.
*   `middle_piece_height`: The height of the central piece.
*   `bracket_width`: The width/thickness of the bracket material.
*   `rill_width`: The width of the stiffness rill.
*   `extra_rill_width_tenth`: An extra width to add to the rill, also in tenths of a millimeter, similar to the hole diameters. So a value of 7 here would mean that the rill is 0.7mm wider than `rill_width`

I'd like the bracket to have rounded edges and fillets for both strength and aesthetics. I also need the rill to have rounded edges on its top. The overall bracket height is fine, but is probably 6mm on the flat pieces and 2mm on the rill.

The bracket should be symmetrical about the middle piece and should have a section that extends past the PSU mounting holes to properly secure the PSU to the frame. I'd like a variable for this extension called `bracket_length_beyond_psu_hole` - but feel free to set a default to something reasonable.

I'm not sure how to best do all this, so I need you to generate the complete OpenSCAD file (or files, if you think it's better to split it up) for me. Make sure it's fully parametric and uses these variables. Also, please use the `cube_fillet` module (and related modules) as I've shown in the reference SCAD file below, for generating the rounded-edge box shapes with fillets.

```
module fillet(radius, height=100, $fn=16) {
    //this creates negative of fillet,
    //i.e. thing to be substracted from object
    translate([-radius, -radius, -height/2-0.01])
        difference() {
            cube([radius*2, radius*2, height+0.02]);
            cylinder(r=radius, h=height+0.02, $fn=16);
        }
}

module cube_negative_fillet(
        size,
        radius=-1,
        vertical=[3,3,3,3],
        top=[0,0,0,0],
        bottom=[0,0,0,0],
        $fn=0
    ){

    j=[1,0,1,0];

    for (i=[0:3]) {
        if (radius > -1) {
            rotate([0, 0, 90*i])
                translate([size[1-j[i]]/2, size[j[i]]/2, 0])
                    fillet(radius, size[2], $fn=$fn);
        } else {
            rotate([0, 0, 90*i])
                translate([size[1-j[i]]/2, size[j[i]]/2, 0])
                    fillet(vertical[i], size[2], $fn=$fn);
        }
        rotate([90*i, -90, 0])
            translate([size[2]/2, size[j[i]]/2, 0 ])
                fillet(top[i], size[1-j[i]], $fn=$fn);
        rotate([90*(4-i), 90, 0])
            translate([size[2]/2, size[j[i]]/2, 0])
                fillet(bottom[i], size[1-j[i]], $fn=$fn);
    }
}

module cube_fillet_inside(
         size,
        radius=-1,
        vertical=[3,3,3,3],
        top=[0,0,0,0],
        bottom=[0,0,0,0],
        $fn=0
    ){
    if (radius == 0) {
        cube(size, center=true);
    } else {
        difference() {
            cube(size, center=true);
            cube_negative_fillet(size, radius, vertical, top, bottom, $fn);
        }
    }
}

module cube_fillet(
        size,
        radius=-1,
        vertical=[3,3,3,3],
        top=[0,0,0,0],
        bottom=[0,0,0,0],
        center=false,
        $fn=0
    ){
    if (center) {
        cube_fillet_inside(size, radius, vertical, top, bottom, $fn);
    } else {
        translate([size[0]/2, size[1]/2, size[2]/2])
            cube_fillet_inside(size, radius, vertical, top, bottom, $fn);
    }
}
```

[Assistant]
psu_bracket.scad:
```
psu_mount_hole_distance = 50; // [0.0:200.0]
psu_mount_hole_d = 4;         // [0.0:10.0]
frame_mount_hole_d = 5;       // [0.0:10.0]
extra_hole_d_tenth = 3;       // [0.0:9.0]
middle_piece_width = 10;      // [0.0:180.0]
middle_piece_height = 10;     // [0.0:30.0]
bracket_width = 12;           // [0.0:30.0]
rill_width = 5;               // [0.0:10.00]
extra_rill_width_tenth = 7;   // [0.0:9.0]

/* [Hidden] */
rill_height = 2;
rill_round_edge = 1;
bracket_round_edge = 1.5;
bracket_height = 6;
bracket_length_beyond_psu_hole = 7.5;

rotate([90,0,0])
difference()
{

  extra_rill_width = extra_rill_width_tenth / 10;

  union()
  {
    // Middle piece
    translate([-middle_piece_width/2 - bracket_round_edge*2.25, 0, middle_piece_height])
      cube_fillet([middle_piece_width+bracket_round_edge*4.5, bracket_width, bracket_height], vertical=[0,0,0,0], top=[0,bracket_round_edge,0,bracket_round_edge]);

    length = sqrt(2 * pow(middle_piece_height, 2));

    // Angled piece (+x)
    translate([middle_piece_width/2+middle_piece_height,bracket_width,0])
      rotate([0,-45,180])
        translate([-bracket_round_edge/2,0,0])
          cube_fillet([length+4.11, bracket_width, bracket_height], vertical=[0,0,0,0], top=[0,0,0,bracket_round_edge], bottom=[0,bracket_round_edge,0,bracket_round_edge]);

    // Angled piece (-x)
    translate([-middle_piece_width/2-middle_piece_height,0,0])
      rotate([0,-45,0])
        translate([-bracket_round_edge/2,0,0])
          cube_fillet([length+4.11, bracket_width, bracket_height], vertical=[0,0,0,0], top=[0,0,0,bracket_round_edge], bottom=[0,bracket_round_edge,0,bracket_round_edge]);

    outer_piece_l = (psu_mount_hole_distance-middle_piece_width)/2-middle_piece_height+bracket_length_beyond_psu_hole+bracket_round_edge/2;

    // Outer piece (+x)
    translate([middle_piece_height + middle_piece_width/2 - bracket_round_edge/2,0,0])
      cube_fillet([outer_piece_l, bracket_width, bracket_height], vertical=[0,0,0,0], top=[0,0,0,bracket_round_edge], bottom=[0,bracket_round_edge,0,bracket_round_edge]);

    // Outer piece (-x)
    rotate([0,0,180])
      translate([middle_piece_height + middle_piece_width/2 - bracket_round_edge/2,-bracket_width,0])
        cube_fillet([outer_piece_l, bracket_width, bracket_height], vertical=[0,0,0,0], top=[0,0,0,bracket_round_edge], bottom=[0,bracket_round_edge,0,bracket_round_edge]);

    // Rill
    translate([-(rill_width+extra_rill_width)/2,0,bracket_height + middle_piece_height])
      cube_fillet([rill_width+extra_rill_width, bracket_width, rill_height], vertical=[0,0,0,0], top=[0,rill_round_edge,0,rill_round_edge]);
  }

  extra_hole_d = extra_hole_d_tenth / 10;

  // PSU Mounting holes
  translate([psu_mount_hole_distance/2, bracket_width/2, -0.05])
    cylinder(d=psu_mount_hole_d+extra_hole_d, h = bracket_height + 0.1, $fn=18);

  translate([-psu_mount_hole_distance/2,bracket_width/2,-0.05])
    cylinder(d=psu_mount_hole_d+extra_hole_d, h = bracket_height + 0.1, $fn=18);

  // Frame mounting hole
  translate([0, bracket_width/2, middle_piece_height-0.05])
    cylinder(d=frame_mount_hole_d+extra_hole_d, h = bracket_height + rill_height + 0.1, $fn=18);

  // Hole in the rill
  rill_hole_width = frame_mount_hole_d + extra_hole_d + 3;
    translate([-(rill_width+extra_rill_width)/2 - 0.05, bracket_width / 2 - rill_hole_width / 2,bracket_height + middle_piece_height])
      cube([rill_width+extra_rill_width + 0.1, rill_hole_width, rill_height+ 0.05]);
}

// http://axuv.blogspot.nl/2012/05/openscad-helper-funcions-for-better.html
module fillet(radius, height=100, $fn=16) {
    //this creates negative of fillet,
    //i.e. thing to be substracted from object
    translate([-radius, -radius, -height/2-0.01])
        difference() {
            cube([radius*2, radius*2, height+0.02]);
            cylinder(r=radius, h=height+0.02, $fn=16);
        }
}

module cube_negative_fillet(
        size,
        radius=-1,
        vertical=[3,3,3,3],
        top=[0,0,0,0],
        bottom=[0,0,0,0],
        $fn=0
    ){

    j=[1,0,1,0];

    for (i=[0:3]) {
        if (radius > -1) {
            rotate([0, 0, 90*i])
                translate([size[1-j[i]]/2, size[j[i]]/2, 0])
                    fillet(radius, size[2], $fn=$fn);
        } else {
            rotate([0, 0, 90*i])
                translate([size[1-j[i]]/2, size[j[i]]/2, 0])
                    fillet(vertical[i], size[2], $fn=$fn);
        }
        rotate([90*i, -90, 0])
            translate([size[2]/2, size[j[i]]/2, 0 ])
                fillet(top[i], size[1-j[i]], $fn=$fn);
        rotate([90*(4-i), 90, 0])
            translate([size[2]/2, size[j[i]]/2, 0])
                fillet(bottom[i], size[1-j[i]], $fn=$fn);
    }
}

module cube_fillet_inside(
         size,
        radius=-1,
        vertical=[3,3,3,3],
        top=[0,0,0,0],
        bottom=[0,0,0,0],
        $fn=0
    ){
    if (radius == 0) {
        cube(size, center=true);
    } else {
        difference() {
            cube(size, center=true);
            cube_negative_fillet(size, radius, vertical, top, bottom, $fn);
        }
    }
}

module cube_fillet(
        size,
        radius=-1,
        vertical=[3,3,3,3],
        top=[0,0,0,0],
        bottom=[0,0,0,0],
        center=false,
        $fn=0
    ){
    if (center) {
        cube_fillet_inside(size, radius, vertical, top, bottom, $fn);
    } else {
        translate([size[0]/2, size[1]/2, size[2]/2])
            cube_fillet_inside(size, radius, vertical, top, bottom, $fn);
    }
}
```


[User]
I'd like to design a slide-on condenser for a tube, and I'd like it to be parametric so I can easily adjust the dimensions. The design I have in mind involves a spiraling water channel that closely follows the surface of the tube, ensuring maximum contact. I've got some existing code for reference, but I'd prefer a fresh design with a more flexible approach.

Here are the key features and parameters I need:

*   **Tube Diameter (pipe):** The diameter of the central tube the condenser will slide onto.
*   **Channel Width (gauge):** The width of the water channel.
*   **Hose Connector Diameter (hose):**  The diameter of the hose connector for inlet and outlet.
*   **Slack:** A small allowance for fit between parts, to allow easy assembly.
*   **Joint Slack (slack_joint):** Extra allowance for fit at the connection points between segments.
*  **Spiral Length (total_length):** Total length of the spiral channel. The condenser will be made of multiple segments, this will define the total length.
*  **Segment Length (segment_length):** The length of a single segment of the condenser.  This will be used to calculate the number of segments.
* **Spiral Pitch (pitch):** How much the spiral rises for each rotation.

The condenser itself will be created from segments of the spiral channel stacked together, starting with a base segment. At the ends, there needs to be a connection to a hose, as well as an optional joint that can be used to connect more segments. I'd like the output to be structured in a way that allows easily disabling or enabling the printing of the joints or the condenser segments.

The general structure will be:
* A base segment with a connector for a hose.
* A number of midsection segments.
*  A joint that can be added to the base, and the midsection.

For the individual segments:
*   The water channel will wrap around the tube and there should be a small space to keep the water flowing.
*   The channel should gradually rise with each rotation, using the `pitch` parameter.
*   The end of a segment is the start of the next, there should be a join to allow water to flow through.

For the base segment:
*  The same spiral of the midsections, but with a hose connector at the end.
*  A small space at the start of the channel to allow water to enter.

For the joint:
*  A spherical shape.
*  An extra channel around the edge of the sphere to help it fit to other joints and midsections.
*  A planar base to print it correctly.

I'm planning to use this with a 3D printer, so any needed printability considerations would be great. I'd also like it if I could control the smoothness of the curves with `$fn`, that way I can trade off between print time and detail.

Could you generate an OpenSCAD file, or multiple files, using these parameters?  It would also be great if it could incorporate the BOSL2 library, if that would be helpful, but it's not strictly necessary.

[Assistant]
condenser.scad:
```
$fn=10;

slack = 0.2;
slack_joint = 0.5;
pipe  = 3;
gauge = 2;
hose  = 9/2;
print_joint = true;
print_condenser = false;

tube    = pipe+slack;   //print=3.2
coolout = tube*2;   //print=6.4
coolin  = coolout-gauge;
shift   = (coolout*2-2.5);
slope   = shift/100;    //print=9
joint   = tube+coolout+gauge*1.5;

//Joint
if(print_joint){
    difference(){
        scale([1,1,1.2]){
            sphere(r=joint,$fn=50);
        }
        union(){
            translate([0,0,shift]){midsection_extra(slack_joint);}
            translate([0,0,0]){midsection_extra(slack_joint);}
            translate([0,0,-shift]){midsection_extra(slack_joint);}
            translate([0,0,-2*shift]){midsection_extra(slack_joint);}
            translate([-25,-25,joint/1.5]){ cube([50,50,10]);}
            translate([-25,-25,-joint/1.5-10]){ cube([50,50,10]);}
        }
    }
}

if(print_condenser){
    difference(){
        union(){
            bottom_positive();
            translate([0,0,shift])  {midsection_positive();}
            translate([0,0,shift*2]){midsection_positive();}
            translate([0,0,shift*3]){midsection_positive();}
        }
        union(){
            bottom_negative();
            translate([0,0,shift])  {midsection_negative();}
            translate([0,0,shift*2]){midsection_negative();}
            translate([0,0,shift*3]){midsection_negative();}

            translate([0,0,-10]){cylinder(r=tube,h=100,$fn=50);}
            translate([-25,-25,shift/2+shift*3]){cube([50,50,20]);}

        }
    }
}

module bottom_positive(){
render(){
    for(i=[0:1:100]){
        translate([0,0,i*slope]){
            rotate([0,0,i*3.6]){
                rotate([0,90,0]){
                    translate([0,tube,0]){
                        cylinder(r=coolout,h=0.61,center=true,$fn=24);
                    }
               }
            }
        }
    }
    rotate([0,0,0]){
        rotate([0,90,0]){
            base = pipe*2;
            translate([0,tube,base/2]){
                cylinder(r=coolout,h=base,center=true,$fn=48);
            }
            translate([0,tube,5+base]){
                cylinder(r=hose,h=10,center=true,$fn=48);
                translate([0,0,3]) {scale([1,1,0.25]){ sphere(r=hose+0.5,$fn=50);}}
                translate([0,0,1]) {scale([1,1,0.25]){ sphere(r=hose+0.5,$fn=50);}}
                translate([0,0,-1]){scale([1,1,0.25]){ sphere(r=hose+0.5,$fn=50);}}
            }
        }
    }
    translate([0,0,-coolout-3]){
        cylinder(r=pipe*2,h=coolout+3,$fn=50);

    }
}
}

module bottom_negative(){
   render(){
    union(){
        for(i=[0:1:100]){
            translate([0,0,i*slope]){
                rotate([0,0,i*3.6]){
                    rotate([0,90,0]){
                        translate([0,tube,0]){
                            cylinder(r=coolin,h=0.612,center=true);
                        }
                    }
                }
            }
        }
        rotate([0,0,0]){
            rotate([0,90,0]){
                translate([0,tube,20]){
                    cylinder(r=hose-gauge,h=40,center=true);
                }
            }
        }
    }
      translate([0,0,-coolout-3.01]){cylinder(r=tube+1,h=3,$fn=50);}

 }
}

module midsection_extra(extra){
   for(i=[1:1:100]){
        translate([0,0,i*slope]){
            rotate([0,0,i*3.6]){
                rotate([0,90,0]){
                    translate([0,tube,0]){
                        cylinder(r=coolout+extra,h=0.61,center=true,$fn=24);
                    }
               }
            }
        }
    }
}

module midsection_positive(){
  //render(){
    for(i=[1:1:100]){
        translate([0,0,i*slope]){
            rotate([0,0,i*3.6]){
                rotate([0,90,0]){
                    translate([0,tube,0]){
                        cylinder(r=coolout,h=0.61,center=true,$fn=24);
                    }
               }
            }
        }
    }
 //  }
}

module midsection_negative(){
  // render(){
    union(){
        for(i=[1:1:100]){
            translate([0,0,i*slope]){
                rotate([0,0,i*3.6]){
                    rotate([0,90,0]){
                        translate([0,tube,0]){
                            cylinder(r=coolin,h=0.612,center=true);
                        }
                    }
                }
            }
        }
    }
//}
}

```


[User]
Hey, I'm looking to create a parametric OpenSCAD model for creating tubes with a customizable hole pattern. I've been messing with some code, but I'd like a more robust and organized version, preferably using a well-established library if possible.

Here's what I need:

**Core Shape:** I want a rectangular tube. I need to control the overall length, width, and height of the tube. I also want to be able to specify the wall thickness, to make it hollow. All of these dimensions should be in millimeters and should be parametric.

**Hole Pattern:** The tubes will have holes drilled on all four sides. The hole pattern should be controlled by two parameters: the diameter of the holes and the spacing between holes. I'd like independent control over the hole spacing along the length (X-axis) and the width (Y-axis) of the tube. The holes should be centered along their respective axes. If the hole spacing doesn't evenly divide the side's length, the pattern should still center on the side and distribute the holes as evenly as possible.

**Parametric Control:** Everything should be easily modified through parameters at the top of the file. I'd like to see well-commented code. The hole pattern should automatically adjust based on the given spacing, so that the pattern stays within the bounds of each side.

**Units:** I would like to work entirely in mm, and have the script perform the necessary conversion to in when printing on a 3d printer.

**Libraries:** Could you use the BOSL2 library for this? It seems to have some good helper functions that could come in handy.

Ideally, the output would be a single `.scad` file that I can open and modify. It would have clear comments that explain what each parameter does. Thanks for your help!

[Assistant]
Tube_Calculator.scad:
```
/*[Standard Hole Pattern]*/
// Length of tube:
Length = 12;
//Width of tube:
Width = 2;
//Height of tube:
Height = 2;
/*[Advanced]*/
//Wall thickness:
Wall_Thickness = .125;
//Hole Diameter:
Hole_Size = .201;
//Distance between holes on Y axis
Hole_Spacing_On_Y_Axis = 0.5;
//Distance between holes on X Axis
Hole_Spacing_On_X_Axis = 0.5;

/*[hidden]*/
holes = 0;
nx = Length;
ny = Width-Wall_Thickness;
nz = Height - Wall_Thickness;
$fn = 100;

module tube() {
    difference() {
        scale([25.4, 25.4, 25.4]) cube([Length, Width, Height], center = true);
        scale([25.4, 25.4, 25.4]) cube ([nx, ny, nz], center = true);
    }
}
module tubewithtop() {
if (Width == 1) {
     difference() {
     tube();
       for (holes =[0:Hole_Spacing_On_X_Axis:(Length/2-Hole_Spacing_On_X_Axis)]) {
           scale([25.4, 25.4, 25.4]) translate ([holes,0 , 0])
               cylinder(d = Hole_Size, h = Height, center = true);
           scale([25.4, 25.4, 25.4]) translate ([- holes,0 , 0])
               cylinder(d = Hole_Size, h = Height, center = true);
     }
}
}
else if (Width == 2) {
    difference() {
        tube();
            for (holes = [0:Hole_Spacing_On_X_Axis:(Length/2-Hole_Spacing_On_X_Axis)]) {
        scale([25.4, 25.4, 25.4]) translate([holes, Hole_Spacing_On_X_Axis, 0])
            cylinder(d = Hole_Size, h = Height, center = true);
        scale([25.4, 25.4, 25.4]) translate([- holes, - Hole_Spacing_On_X_Axis, 0])
             cylinder(d = Hole_Size, h = Height, center = true);
        scale([25.4, 25.4, 25.4]) translate([holes, - Hole_Spacing_On_X_Axis, 0])
             cylinder(d = Hole_Size, h = Height, center = true);
        scale([25.4, 25.4, 25.4]) translate([- holes, Hole_Spacing_On_X_Axis, 0])
             cylinder(d = Hole_Size, h = Height, center = true);
    }
        scale([25.4, 25.4, 25.4]) translate([Length/2-Hole_Spacing_On_X_Axis, 0, 0])
            cylinder(d = Hole_Size, h = Height, center = true);
        scale([25.4, 25.4, 25.4]) translate([-Length/2+Hole_Spacing_On_X_Axis, 0, 0])
            cylinder(d = Hole_Size, h = Height, center = true);
}
}
}

if (Height == 1) {
    difference() {
       tubewithtop();
        for (holes =[0:Hole_Spacing_On_Y_Axis:(Length/2-Hole_Spacing_On_X_Axis)]) {
            scale([25.4, 25.4, 25.4]) rotate([90, 0, 0]) translate ([holes,0 , 0])
                cylinder(d = Hole_Size, h = Width, center = true);
             scale([25.4, 25.4, 25.4]) rotate([90, 0, 0]) translate ([-holes,0 , 0])
                cylinder(d = Hole_Size, h = Width, center = true);
        }
    }
}
else if (Height == 2) {
    difference() {
        tubewithtop();
            for (holes = [0:Hole_Spacing_On_Y_Axis:(Length/2-Hole_Spacing_On_Y_Axis)]) {
            scale([25.4, 25.4, 25.4]) rotate([90, 0, 0]) translate ([holes, Hole_Spacing_On_Y_Axis , 0])
                cylinder(d = Hole_Size, h = Width, center = true);
            scale([25.4, 25.4, 25.4]) rotate([90, 0, 0]) translate ([-holes,Hole_Spacing_On_Y_Axis , 0])
                cylinder(d = Hole_Size, h = Width, center = true);
            scale([25.4, 25.4, 25.4]) rotate([90, 0, 0]) translate ([holes, -Hole_Spacing_On_Y_Axis , 0])
                cylinder(d = Hole_Size, h = Width, center = true);
            scale([25.4, 25.4, 25.4]) rotate([90, 0, 0]) translate ([-holes,-Hole_Spacing_On_Y_Axis , 0])
                cylinder(d = Hole_Size, h = Width, center = true);
            }
        scale([25.4, 25.4, 25.4]) rotate([90, 0, 0]) translate([Length/2-Hole_Spacing_On_Y_Axis, 0, 0])
            cylinder(d = Hole_Size, h = Width, center = true);
        scale([25.4, 25.4, 25.4])rotate([90, 0, 0])translate([-Length/2+Hole_Spacing_On_Y_Axis, 0, 0])
            cylinder(d = Hole_Size, h = Width, center = true);

}
}

```


[User]
Okay, I need a set of OpenSCAD files to generate customizable tube endcaps. I've seen a script that does it, but I'd like to have a more modular approach.

Here's the functionality I'm looking for:

*   **Core Endcap Module:** This will be the main module that generates the endcap. It needs parameters for:
    *   `InnerMAXDiameter`: The maximum inner diameter of the gripping rings.
    *   `InnerMINDiameter`: The minimum inner diameter of the gripping rings (same as `InnerMAXDiameter` for cylindrical).
    *   `Rings`: The number of gripping rings.
    *   `RingHeight`: The height of each gripping ring.
    *   `RingsRatio`: A ratio determining the diameter of each ring relative to the previous one (1 for uniform, less than 1 for conical).
    *   `CAPOuterDiameter`: The outer diameter of the cap portion.
    *   `CAPHeight`: The overall height of the cap, including the fillet.
    *   `Facets`: The resolution for curves.
    *   `InnerHoleDiameter`: The diameter of the hole inside the rings.
    *   `InnerHoleHeight`: The height of the inner hole.
    *   `Fillet`: The radius of the fillet on the cap.

*   **Separate Ring Module:** I'd like a separate module to generate a single ring. This module should take parameters for its inner and outer radius, height, and position (z-offset), and facets. This will make the core module cleaner.

*   **Separate Fillet Module:**  I'd also like a separate module to generate the fillet. This would make it easier to implement a fillet at other places if I needed to. It should take a radius, and height, and it should be able to be positioned.

*   **Main Module Integration:** The core endcap module should use the separate ring and fillet modules to generate the final endcap.

I think using named modules instead of anonymous `for` loops could make things easier to read and modify later. I’d also like for it to be easily parameterized and for it to work with the following use cases:
* uniform rings
* conical rings
* end caps with fillets
* end caps without fillets
* different amounts of rings
* end caps with holes going all the way through
* end caps with holes that don't go all the way through

I'm hoping for a flexible set of files that I can customize to fit a variety of tube sizes. I think it would be good to use descriptive names for the modules and parameters. It doesn't seem that there are any common OpenSCAD libraries that I need here.

[Assistant]
Tube_endcap.scad:
```
// OpenSCAD simple script for a customizable round tube endcap
// By Magonegro JUNE-2016
// Use your own parameters to customize your endcap.
// Open this in OpenSCAD, then press F6 wait for it to render the CAP and export to stl.
// At print time remember that Buildplate only support ir required tor the upper CAP external overhanging diameter.
InnerMAXDiameter = 20; // Max inner diameter for the rings
InnerMINDiameter = 18; // Keep same as MAX for cylindrical shape
Rings=6;        // Number of rings.
RingHeight=3;   // Max insertion height = Rings*RighHeight
RingsRatio=1;   // Each ring's diameter will be this ratio the vaule of its precedent.
                // Enter 1 for uniform rings or 0.97 (for 6 rings) for a conical shape.
                // Beware the inner hole, it should be smaller than the last ring.
CAPOuterDiameter=24; // This should equal tube external diameter
CAPHeight=10; // Height of the CAP, included Fillet
Facets=100; // Resolution parameter, minimum value 3 for a triangular CAP, Defaults to 100 for smooth round CAP. Values lower than 30 could render artifacts
InnerHoleDiameter=InnerMINDiameter/1.5; // Average value
InnerHoleHeight=Rings*RingHeight; // Defaults till the cap
Fillet=6; // Fillet radius for the CAP, should be less or equal than CAPHeight. Zero for no fillet. Should be also less o equal than CAPOuterDiameter/2.

module MakeCap()
{
    difference()
    {
        union()
        {
            // Rings
            for(i=[0:Rings-1])
            {
                Ratio=1-((1-RingsRatio)*(Rings-i));
                translate([0,0,i*RingHeight])
                    cylinder(h = RingHeight,
                        r1 = Ratio*InnerMINDiameter/2,
                        r2 = Ratio*InnerMAXDiameter/2,
                        center = false,$fn=Facets);
            }
            // Cap
            translate([0,0,RingHeight*Rings])
                cylinder(h = CAPHeight-Fillet,
                    r = CAPOuterDiameter/2,
                    center = false,$fn=Facets);
            translate([0,0,RingHeight*Rings+CAPHeight-Fillet])
                cylinder(h = Fillet,
                    r = CAPOuterDiameter/2-Fillet,
                    center = false,$fn=Facets);
            rotate([0,0,360/2*Facets])
            translate([0, 0, RingHeight*Rings+CAPHeight-Fillet])
                rotate_extrude(convexity = 10,$fn = Facets)
                    translate([CAPOuterDiameter/2-Fillet, 0, 0])
                        intersection()
                            {
                            circle(r = Fillet, $fn = Facets);
                            square(Fillet);
                            }
        }
    // Hole
    cylinder(h = InnerHoleHeight,
                r = InnerHoleDiameter/2,
                center = false,$fn=Facets);

    }
}

// Main
MakeCap();

```