### Module Documentation Example

Source: https://github.com/belfryscad/bosl2/blob/master/WRITING_DOCS.md

Documents a module, including usage, arguments, and an example. The 'Module' header is used, and it's recommended to include Usage, Arguments, and Example sub-blocks.

```openscad
// Module: cross()
// Usage:
//   cross(size);
// Description:
//   Creates a 2D cross/plus shape.
// Arguments:
//   size = The scalar size of the cross.
// Example(2D):
//   cross(size=100);
module cross(size=1) {
    square([size, size/3], center=true);
    square([size/3, size], center=true);
}
```

--------------------------------

### Function Documentation Example

Source: https://github.com/belfryscad/bosl2/blob/master/WRITING_DOCS.md

Documents a function, including usage, arguments, and an example. The 'Function' header is used, and it's recommended to include Usage, Arguments, and Example sub-blocks.

```openscad
// Function: vector_angle()
// Usage:
//   ang = vector_angle(v1, v2);
// Description:
//   Calculates the angle between two vectors in degrees.
// Arguments:
//   v1 = The first vector.
//   v2 = The second vector.
// Example:
//   v1 = [1,1,0];
//   v2 = [1,0,0];
//   angle = vector_angle(v1, v2);
//   // Returns: 45
function vector_angle(v1,v2) =
    acos(max(-1,min(1,(vecs[0]*vecs[1])/(norm0*norm1))));
```

--------------------------------

### Example Block with Multiple Shapes

Source: https://github.com/belfryscad/bosl2/blob/master/WRITING_DOCS.md

Demonstrates a multi-line example script for generating shapes. Images are generated by running the script in OpenSCAD.

```openscad
// Example: Example description
//   cylinder(h=100, d1=75, d2=50);
//   up(100) cylinder(h=100, d1=50, d2=75);
```

```openscad
// Example(Spin,VPD=444): Animated shape that spins to show all faces.
//   cube([10,100,50], center=true);
//   cube([100,10,30], center=true);
```

--------------------------------

### Constant Documentation Example

Source: https://github.com/belfryscad/bosl2/blob/master/WRITING_DOCS.md

Documents a code constant with a description and an example. The 'Constant' header is used for this purpose.

```openscad
// Constant: PHI
// Description: The golden ratio phi.
PHI = (1+sqrt(5))/2;
```

--------------------------------

### Function and Module Documentation Example

Source: https://github.com/belfryscad/bosl2/blob/master/WRITING_DOCS.md

Documents a function that also has a related module. Includes usage for both function and module calls, description, arguments, and examples for each.

```openscad
// Function&Module: oval()
// Topics: 2D Shapes, Geometry
// Usage: As a Module
//   oval(rx,ry);
// Usage: As a Function
//   path = oval(rx,ry);
// Description:
//   When called as a function, returns the perimeter path of the oval.
//   When called as a module, creates a 2D oval shape.
// Arguments:
//   rx = X axis radius.
//   ry = Y axis radius.
// Example(2D): Called as a Function
//   path = oval(100,60);
//   polygon(path);
// Example(2D): Called as a Module

```

--------------------------------

### Torus creation examples

Source: https://github.com/belfryscad/bosl2/wiki/shapes3d.scad

Demonstrates multiple ways to create a torus using different combinations of major/minor radius/diameter arguments. The last example shows converting the torus to a VNF polyhedron.

```openscad
include <BOSL2/std.scad>
// These all produce the same torus.
torus(r_maj=22.5, r_min=7.5);
torus(d_maj=45, d_min=15);
torus(or=30, ir=15);
torus(od=60, id=30);
torus(d_maj=45, id=30);
torus(d_maj=45, od=60);
torus(d_min=15, id=30);
torus(d_min=15, od=60);
vnf_polyhedron(torus(d_min=15, od=60), convexity=4);
```

--------------------------------

### Examples Block with Basic Shapes

Source: https://github.com/belfryscad/bosl2/blob/master/WRITING_DOCS.md

Shows basic geometric shapes using the Examples block, where each line is treated as a separate example.

```openscad
cube(100);
```

```openscad
cylinder(h=100,d=50);
```

```openscad
sphere(d=100);
```

--------------------------------

### Example: VNF Bounds Calculation

Source: https://github.com/belfryscad/bosl2/wiki/vnf.scad

Demonstrates how to use vnf_bounds() to get the bounding box of a cube VNF. The output shows the min and max coordinates.

```OpenSCAD
include <BOSL2/std.scad>
echo(vnf_bounds(cube([2,3,4],center=true)));   // Displays [[-1, -1.5, -2], [1, 1.5, 2]]
```

--------------------------------

### Meshing Worm and Gear Example

Source: https://github.com/belfryscad/bosl2/wiki/gears.scad

Demonstrates how to create and position a worm and a worm gear to show them meshing. The example uses '$fn' for smoothness and rotates the worm to simulate meshing.

```openscad
include <BOSL2/std.scad>
include <BOSL2/gears.scad>
$fn=36;
circ_pitch = 5;
starts = 4;
worm_diam = 30;
worm_length = 50;
gear_teeth=36;
right(worm_diam/2)
  yrot($t*360/starts)
    worm(
       d=worm_diam,

```

--------------------------------

### Move Function Examples: Point, List of Points, and Matrix

Source: https://github.com/belfryscad/bosl2/wiki/transforms.scad

Provides examples of move() function usage for translating points, lists of points, and generating transformation matrices.

```openscad
include <BOSL2/std.scad>
pt1 = move([0,20,30], [15,23,42]);       // Returns: [15, 43, 72]
pt2 = move([0,3,1], [[1,2,3],[4,5,6]]);  // Returns: [[1,5,4], [4,8,7]]
mat2d = move([2,3]);    // Returns: [[1,0,2],[0,1,3],[0,0,1]]
mat3d = move([2,3,4]);  // Returns: [[1,0,0,2],[0,1,0,3],[0,0,1,4],[0,0,0,1]]
```

--------------------------------

### Example: oval() Function Usage

Source: https://github.com/belfryscad/bosl2/blob/master/WRITING_DOCS.md

Demonstrates calling the oval() function to get the path and then using polygon() to render the shape. Ensure $fn is set for accurate rendering.

```openscad
path = oval(100,60);
polygon(path);
```

--------------------------------

### Install openscad-test

Source: https://github.com/belfryscad/bosl2/blob/master/TESTING.md

Install the openscad-test framework using pip. This is a prerequisite for running BOSL2 tests.

```bash
pip install openscad-test
```

--------------------------------

### Create a circle segment using width and thickness

Source: https://github.com/belfryscad/bosl2/wiki/drawing.scad

This example utilizes the `width` and `thickness` parameters to create a circle segment, where the arc starts and ends on the X axis.

```openscad
include <BOSL2/std.scad>
arc(width=60, thickness=20);
```

--------------------------------

### Creating a Valid Polyhedron with vnf_join (Example 4)

Source: https://github.com/belfryscad/bosl2/wiki/vnf.scad

Shows how to create a valid polyhedron by joining multiple consistent VNF pieces. This example meets CGAL requirements for valid polyhedra.

```openscad
include <BOSL2/std.scad>
bottom = vnf_vertex_array([path3d(rect(8)), path3d(rect(5),4)],col_wrap=true,cap1=true);
triangle = yrot(-90,path3d(regular_ngon(n=3,side=5,anchor=LEFT)));
top = up(4,vnf_vertex_array([list_set(right(2.5,triangle),0,[0,0,7]),
                                 right(6,triangle)
                                ], col_wrap=true, cap2=true));
full = vnf_join([bottom,
                      for(theta=[0:90:359]) zrot(theta,top)
                     ]);
vnf_polyhedron(full);
```

--------------------------------

### OpenSCAD Example with $slop

Source: https://github.com/belfryscad/bosl2/wiki/constants.scad

This example shows how to use the $slop constant in OpenSCAD to create a difference between two shapes, effectively defining a gap. It also includes text elements to label the '$slop' and 'gap'.

```openscad
include <BOSL2/std.scad>
$slop = 0.2;
difference() {
  square([20,12],center=true);
  back(3) square([10+2*$slop,11],center=true);
}
back(8) {
  rect([15,5],anchor=FWD);
  rect([10,8],anchor=BACK);
}
color("#000") {
  arrow_path = [[5.1,6.1], [6.0,7.1], [8,7.1], [10.5,10]];
  xflip_copy()
    stroke(arrow_path, width=0.3, endcap1="arrow2");
  xcopies(21) back(10.5) {
      back(1.8) text("$slop", size=1.5, halign="center");
      text("gap", size=1.5, halign="center");
  }
}
```

--------------------------------

### Extract Substring from String

Source: https://github.com/belfryscad/bosl2/wiki/strings.scad

Use substr() to get a portion of a string. Specify start position and length, or just the start position to get the rest of the string. A negative length returns an empty string.

```scad
include <BOSL2/std.scad>
s1=substr("abcdefg",3,3);     // Returns "def"
s2=substr("abcdefg",2);       // Returns "cdefg"
s3=substr("abcdefg",len=3);   // Returns "abc"
s4=substr("abcdefg",[2,4]);   // Returns "cde"
s5=substr("abcdefg",len=-2);  // Returns ""
```

--------------------------------

### Stroke Path with Tail and Arrow Endcaps

Source: https://github.com/belfryscad/bosl2/wiki/Tutorial-Paths

Combine different custom endcap styles for the start and end of the path. This example uses 'tail' for the start and 'arrow' for the end.

```openscad
include <BOSL2/std.scad>
path = [[0,0], [-10,10], [0,20], [10,20], [10,10]];
stroke(path, endcap1="tail", endcap2="arrow");
```

--------------------------------

### Create an arc with a specified start angle

Source: https://github.com/belfryscad/bosl2/wiki/drawing.scad

This example demonstrates creating a wedge arc that starts at a specific angle (45 degrees) and spans a given angle (75 degrees).

```openscad
include <BOSL2/std.scad>
arc(r=30, start=45, angle=75, wedge=true);
```

--------------------------------

### Vaccum connector example using skin()

Source: https://github.com/belfryscad/bosl2/wiki/skin.scad

Demonstrates creating a vacuum connector shape by skinning a series of 2D paths, including rounded corners and circles. Uses slices=0 for a single surface.

```openscad
include <BOSL2/std.scad>
include <BOSL2/rounding.scad>
$fn=32;
base = round_corners(square([2,4],center=true), radius=0.5);
skin([
        path3d(base,0),
        path3d(base,2),
        path3d(circle(r=0.5),3),
        path3d(circle(r=0.5),4),
        for(i=[0:2]) each [path3d(circle(r=0.6), i+4),
                           path3d(circle(r=0.5), i+5)]
    ],slices=0);
```

--------------------------------

### substr_match() Example

Source: https://github.com/belfryscad/bosl2/wiki/strings.scad

Checks if a pattern matches a substring within a larger string starting at a specified index. Returns false if the pattern is too long, the start index is out of bounds, or the pattern does not match.

```openscad
include <BOSL2/std.scad>
a=substr_match("abcde",2,"cd");   // Returns true
b=substr_match("abcde",2,"cx");   // Returns false
c=substr_match("abcde",2,"cdef"); // Returns false
d=substr_match("abcde",-2,"cd");  // Returns false
e=substr_match("abcde",19,"cd");  // Returns false
f=substr_match("abc",1,"");       // Returns true
```

--------------------------------

### Create a Cube using vnf_polyhedron()

Source: https://github.com/belfryscad/bosl2/wiki/Tutorial-VNF

Shows how to create the same cube as the previous example but using the VNF structure with `vnf_polyhedron()`.

```openscad
include <BOSL2/std.scad>
vnf = [
    [
        [-1,-1,-1], [1,-1,-1], [1,1,-1], [-1,1,-1],
        [-1,-1, 1], [1,-1, 1], [1,1, 1], [-1,1, 1],
    ],
    [
        [0,1,2], [0,2,3],  //BOTTOM
        [0,4,5], [0,5,1],  //FRONT
        [1,5,6], [1,6,2],  //RIGHT
        [2,6,7], [2,7,3],  //BACK
        [3,7,4], [3,4,0],  //LEFT
        [6,4,7], [6,5,4]   //TOP
    ]
];
vnf_polyhedron(vnf);
```

--------------------------------

### Create an enveloping worm with multiple starts

Source: https://github.com/belfryscad/bosl2/wiki/gears.scad

This example demonstrates creating an enveloping worm with multiple lead starts, which affects the helix angle. Ensure BOSL2's std.scad and gears.scad libraries are included.

```openscad
include <BOSL2/std.scad>
include <BOSL2/gears.scad>
enveloping_worm(circ_pitch=8, mate_teeth=33, d=30, starts=3, $fn=72);
```

--------------------------------

### Create a Threaded Nut with Custom Bevels and Blunt Start

Source: https://github.com/belfryscad/bosl2/wiki/threading.scad

Generates a threaded nut with custom internal and external bevels, and blunt start threads. This example showcases fine-grained control over thread lead-in and end treatments.

```openscad
include <BOSL2/std.scad>
include <BOSL2/threading.scad>
threaded_nut(nutwidth=16, id=8, h=8, pitch=1.25, bevel1=true, bevel2=true, ibevel1=true, ibevel2=true, blunt_start1=true, blunt_start2=true, $slop=0.1, $fa=1, $fs=1);
```

--------------------------------

### path_join() Examples

Source: https://github.com/belfryscad/bosl2/wiki/rounding.scad

Illustrates the behavior of path_join() with different 'closed' and 'k' parameter settings, showing how paths are joined and rounded.

```APIDOC
## path_join() Example 13

### Description
Demonstrates `closed=true` behavior when the last path doesn't meet the first, resulting in curve-based closure. It highlights that the function fails if segments are parallel and requires intersecting extensions for well-defined rounding.

### Parameters
- `paths` (list of paths): The input paths to join.
- `closed` (boolean, optional): If true, attempts to close the path with a curve. Defaults to false.
- `joint` (number, optional): Specifies the type of joint. Defaults to 3.
- `$fn` (integer, optional): Number of fragments for curves. Defaults to 25.

### Code Example
```scad
include <BOSL2/std.scad>
horiz = [[0,0],[10,0]];
vert = [[0,0],[0,10]];
h2 = [[0,-3],[10,0]];
color("red")stroke(
  path_join([horiz, vert, -h2],closed=true,
            joint=3,$fn=25),
  closed=true,width=.5);
stroke(path_join([horiz, vert, -h2]),width=.3);
```
```

```APIDOC
## path_join() Example 14

### Description
Shows how `closed=true` rounds the start and end junction when applied to a single path.

### Parameters
- `paths` (list of paths): The input paths to join. Expects a single path in this example.
- `joint` (number, optional): Specifies the type of joint. Defaults to 3.
- `closed` (boolean, optional): If true, rounds the start and end junction. Defaults to false.
- `$fn` (integer, optional): Number of fragments for curves. Defaults to 12.

### Code Example
```scad
include <BOSL2/std.scad>
tri = regular_ngon(n=3, r=7);
stroke(path_join([tri], joint=3,closed=true,$fn=12),
       closed=true,width=.5);
```
```

```APIDOC
## path_join() Example 15

### Description
Illustrates joining lines that do not intersect when extended, creating a semi-circular joint. Demonstrates the effect of the `k` parameter on curvature smoothness.

### Parameters
- `paths` (list of paths): The input paths to join.
- `k` (list of numbers, optional): Curvature smoothness parameter. Defaults to 0.5.
- `relocate` (boolean, optional): If true, attempts to relocate paths. Defaults to true.

### Code Example
```scad
include <BOSL2/std.scad>
p=path_join([
             [[1,3],[15,8]],
             [[17,0],[0,0]],
             [[0,-8],[15,-3]]
            ],
            k=[.5,.9],
            relocate=false);
stroke(p);
```
```

--------------------------------

### Example with Hidden Lines

Source: https://github.com/belfryscad/bosl2/blob/master/WRITING_DOCS.md

Illustrates how lines starting with '--' are excluded from the documentation output but included in the image generation script.

```openscad
// Example: Multi-line example.
//   --$fn = 72; // Lines starting with -- aren't shown in docs example text.
//   lst = [
//       "multi-line examples",
//       "are shown in one block",
//       "with a single image.",
//   ];
//   foo(lst, 23, "blah");
```

--------------------------------

### Create a ring region and path with width and thickness

Source: https://github.com/belfryscad/bosl2/wiki/shapes2d.scad

This example generates both a 'region' (solid ring) and a 'path' (outline of the ring) using width and thickness parameters. The path is then rendered as a dashed stroke.

```openscad
include <BOSL2/std.scad>
$fn=128;
region = ring(width=5,thickness=1.5,ring_width=2);
path = ring(width=5,thickness=1.5,ring_width=2,full=false);
stroke(region,width=.25);
color("red") dashed_stroke(path,dashpat=[1.5,1.5],closed=true,width=.25);
```

--------------------------------

### prismoid() Example 16: Gradiant Rounding

Source: https://github.com/belfryscad/bosl2/wiki/shapes3d.scad

Applies gradient rounding to the prismoid edges, specifying different rounding values for the start and end.

```openscad
include <BOSL2/std.scad>
prismoid(100, 80, rounding1=10, rounding2=0, h=30);
```

--------------------------------

### Creating a Connected Pipe Assembly with prism_connector

Source: https://github.com/belfryscad/bosl2/wiki/rounding.scad

This example shows how to construct a connected pipe assembly by defining the exterior and then subtracting the interior. It highlights the use of corrective shifts to maintain uniform pipe walls.

```openscad
include <BOSL2/std.scad>
bigpipe_d=15;
smallpipe_d=9;
wall=1;
h=30;
fillet=3;
sep=30;
shift=5;
shift_fix=wall/(sep-bigpipe_d)*shift;
$fn=128;
back_half()
  difference(){
    // Pipe exterior
    cyl(d=bigpipe_d,h=h,circum=true) let(leftpipe=parent())
    right(sep)
      cyl(d=bigpipe_d,h=h,circum=true) let(rightpipe=parent())
        prism_connector(circle(d=smallpipe_d,$fn=48),
                        leftpipe, RIGHT, rightpipe, LEFT, fillet=fillet, shift2=shift);
    // Interior that will be removed
    cyl(d=bigpipe_d-2*wall,h=h+1,circum=true) let(leftpipe=parent())
    right(sep)
      cyl(d=bigpipe_d-2*wall,h=h+1,circum=true) let(rightpipe=parent())
        prism_connector(circle(d=smallpipe_d-2*wall,$fn=48),
                        leftpipe, RIGHT, rightpipe, LEFT, fillet=fillet,
                        shift1=-shift_fix,shift2=shift+shift_fix);
  }
```

--------------------------------

### join_prism() with Cylinder Base

Source: https://github.com/belfryscad/bosl2/wiki/rounding.scad

Demonstrates the usage of join_prism() with a cylinder as the base shape. This example shows the basic setup for attaching a prism to a cylinder.

```openscad
include <BOSL2/std.scad>
flower = [for(theta=lerpn(0,360,180,endpoint=false))
          (15+1.3*sin(6*theta))*[cos(theta),sin(theta)]];
join_prism(flower,base="cylinder",length=18, fillet=3, n=12);
cylinder(h=5,r=25);
```

--------------------------------

### Slop Calibration Part Example

Source: https://github.com/belfryscad/bosl2/wiki/constants.scad

This example demonstrates how to generate a calibration part to determine the optimal $slop value for your 3D printer. Adjust the 'holesize' and 'gap' variables to test different tolerances. The comments within the code suggest modifications for testing cylinders instead of cubes.

```openscad
include <BOSL2/std.scad>
min_slop = 0.00;
slop_step = 0.05;
holes = 6;
holesize = [10,10,10];
gap = 5;

```

--------------------------------

### Path Join with Single Path and Closed=true (Example 14)

Source: https://github.com/belfryscad/bosl2/wiki/rounding.scad

Shows how `closed=true` rounds the start and end junction when a single path is provided to `path_join`.

```OpenSCAD
include <BOSL2/std.scad>
tri = regular_ngon(n=3, r=7);
stroke(path_join([tri], joint=3,closed=true,$fn=12),
       closed=true,width=.5);
```

--------------------------------

### Using worm_gear() as a Function

Source: https://github.com/belfryscad/bosl2/wiki/gears.scad

This example shows how to call worm_gear() as a function to get its geometry, which can then be used for further operations like creating a polyhedron. The output of worm_gear() is a 2D profile that can be extruded or used in other ways.

```openscad
include <BOSL2/std.scad>
include <BOSL2/gears.scad>
vnf = worm_gear(circ_pitch=8, teeth=30, worm_diam=30, worm_starts=1);
vnf_polyhedron(vnf);
```

--------------------------------

### Create a Standard Rack

Source: https://github.com/belfryscad/bosl2/wiki/gears.scad

Generates a standard rack using pitch, teeth, and thickness parameters. The backing parameter controls the rack's thickness.

```OpenSCAD
include <BOSL2/std.scad>
include <BOSL2/gears.scad>
rack(pitch=5, teeth=10, thickness=5, backing=5, helical=30);
```

--------------------------------

### Call enveloping_worm() as a function and use vnf_polyhedron()

Source: https://github.com/belfryscad/bosl2/wiki/gears.scad

This example shows how to call enveloping_worm() as a function to get a VNF (Vectorized Numerical Format) and then render it using vnf_polyhedron(). Ensure BOSL2's std.scad and gears.scad libraries are included.

```openscad
include <BOSL2/std.scad>
include <BOSL2/gears.scad>
vnf = enveloping_worm(circ_pitch=8, mate_teeth=37, d=35, starts=2, left_handed=true, pressure_angle=20, $fn=72);
vnf_polyhedron(vnf);
```

--------------------------------

### Create a sphere with custom orientation

Source: https://github.com/belfryscad/bosl2/wiki/shapes3d.scad

This example demonstrates creating a sphere, setting its anchor and spin, and then orienting its 'top' towards a specified direction. Ensure BOSL2 std library is included.

```openscad
include <BOSL2/std.scad>
sphere(d=100, anchor=FRONT, spin=45, orient=FWD);
```

--------------------------------

### mask2d_smooth() Example 2: Mask defined by joint length

Source: https://github.com/belfryscad/bosl2/wiki/masks.scad

Creates a 2D mask shape defined by the 'joint' parameter, specifying the distance from the edge where the roundover starts. A larger 'excess' value is used to better visualize the mask's extent. Ensure BOSL2 std library is included.

```openscad
include <BOSL2/std.scad>
mask2d_smooth(joint=10,excess=0.5);
```

--------------------------------

### OpenSCAD Usage Block Example

Source: https://github.com/belfryscad/bosl2/blob/master/WRITING_DOCS.md

Illustrates a Usage block for documenting typical ways to use a function or module, including different parameter forms.

```openscad
// Usage: Typical Usage
//   x = foo(a, b, c);
//   x = foo([a, b, c, ...]);
```

--------------------------------

### Create Arc Path with Starting Angle

Source: https://github.com/belfryscad/bosl2/wiki/Tutorial-Paths

Creates an arc path starting at a specified angle using the 'start' argument. Include BOSL2's std.scad.

```openscad
include <BOSL2/std.scad>
path = arc(start=45, r=30, angle=120);
stroke(path, endcap2="arrow2");
```

--------------------------------

### Create a threaded rod with detailed specifications

Source: https://github.com/belfryscad/bosl2/wiki/threading.scad

Demonstrates creating a threaded rod using detailed specifications for diameter, length, and pitch. This example highlights the flexibility in defining thread parameters.

```openscad
include <BOSL2/std.scad>
include <BOSL2/threading.scad>
threaded_rod(d=[10, 1.5, 12], length=20, pitch=1.5);
```

--------------------------------

### Create a sphere with custom anchoring

Source: https://github.com/belfryscad/bosl2/wiki/shapes3d.scad

This example demonstrates creating a sphere and positioning its anchor point to the front. Ensure BOSL2 std library is included.

```openscad
include <BOSL2/std.scad>
sphere(d=100, anchor=FRONT);
```

--------------------------------

### Create Meshing Crown and Spur Gears

Source: https://github.com/belfryscad/bosl2/wiki/gears.scad

This example demonstrates how to create a crown gear and a spur gear that mesh together. It calculates pitch radii and sets appropriate orientations and positions for meshing. Ensure BOSL2 libraries are included.

```openscad
include <BOSL2/std.scad>
include <BOSL2/gears.scad>
mod=1;
cteeth=40;
ppr=17;
backing=3;
PA=20;
face=5;
cpr = pitch_radius(mod=mod, teeth=cteeth);
ppr = pitch_radius(mod=mod, teeth=pteeth);
crown_gear(mod=mod, teeth=cteeth, backing=backing,
    face_width=face, pressure_angle=PA);
back(cpr+face/2)
  up(ppr)
    spur_gear(mod=mod, teeth=pteeth,
        pressure_angle=PA, thickness=face,
        orient=BACK, gear_spin=180/pteeth,
```

--------------------------------

### snap_pin_socket() - Integrated into a Cube

Source: https://github.com/belfryscad/bosl2/wiki/joiners.scad

Demonstrates integrating snap_pin_socket() into a larger object, such as a cube. This example shows how to difference the socket from a solid and position multiple sockets.

```openscad
include <BOSL2/std.scad>
include <BOSL2/joiners.scad>
$fn=40;
diff("socket") cuboid([20,20,20])
  tag("socket"){
    attach(TOP) snap_pin_socket("standard");
    position(TOP+FRONT)snap_pin_socket("standard");
  }
```

--------------------------------

### Create 5 copies spaced 20 units apart along the Y axis starting at [0,0,0]

Source: https://github.com/belfryscad/bosl2/wiki/Tutorial-Distributors

Use the `sp=` argument with `ycopies()` to specify a starting point. For `ycopies()`, the line extends to the back of the starting point.

```openscad
include <BOSL2/std.scad>
ycopies(20, n=5, sp=[0,0,0]) sphere(d=10);
```

--------------------------------

### join_prism() with Scaling

Source: https://github.com/belfryscad/bosl2/wiki/rounding.scad

Demonstrates how to scale the prism using the scale parameter.

```openscad
include <BOSL2/std.scad>
flower = [for(theta=lerpn(0,360,180,endpoint=false)) (15+1.3*sin(6*theta))*[cos(theta),sin(theta)]];
join_prism(flower,base="cylinder",base_r=30, length=18,
           fillet=4, n=12,scale=.5);
xcyl(r=30,l=75,circum=true,$fn=64);
```

--------------------------------

### Create 5 copies spaced 20 units apart along the Z axis starting at [0,0,0]

Source: https://github.com/belfryscad/bosl2/wiki/Tutorial-Distributors

Use the `sp=` argument with `zcopies()` to specify a starting point. For `zcopies()`, the line extends upwards from the starting point.

```openscad
include <BOSL2/std.scad>
zcopies(20, n=5, sp=[0,0,0]) sphere(d=10);
```

--------------------------------

### Create a sphere with custom anchoring and spin

Source: https://github.com/belfryscad/bosl2/wiki/shapes3d.scad

This example shows how to create a sphere, set its anchor point to the front, and then rotate it around the Z-axis. Ensure BOSL2 std library is included.

```openscad
include <BOSL2/std.scad>
sphere(d=100, anchor=FRONT, spin=45);
```

--------------------------------

### Create 5 copies spaced 20 units apart along the X axis starting at [0,0,0]

Source: https://github.com/belfryscad/bosl2/wiki/Tutorial-Distributors

Use the `sp=` argument with `xcopies()` to specify a starting point. For `xcopies()`, the line extends to the right of the starting point.

```openscad
include <BOSL2/std.scad>
xcopies(20, n=5, sp=[0,0,0]) sphere(d=10);
```

--------------------------------

### Create a Cube using polyhedron()

Source: https://github.com/belfryscad/bosl2/wiki/Tutorial-VNF

Demonstrates the basic usage of the `polyhedron()` module with explicit vertex and face lists to create a cube.

```openscad
include <BOSL2/std.scad>
verts = [
    [-1,-1,-1], [1,-1,-1], [1,1,-1], [-1,1,-1],
    [-1,-1, 1], [1,-1, 1], [1,1, 1], [-1,1, 1]
];
faces = [
    [0,1,2], [0,2,3],  //BOTTOM
    [0,4,5], [0,5,1],  //FRONT
    [1,5,6], [1,6,2],  //RIGHT
    [2,6,7], [2,7,3],  //BACK
    [3,7,4], [3,4,0],  //LEFT
    [6,4,7], [6,5,4]   //TOP
];
polyhedron(verts, faces);
```

--------------------------------

### path_join() Example 1: Joining simple paths

Source: https://github.com/belfryscad/bosl2/wiki/rounding.scad

Connects three simple paths end-to-end. This is a basic usage without explicit rounding parameters.

```OpenSCAD
include <BOSL2/std.scad>
horiz = [[0,0],[10,0]];
vert = [[0,0],[0,10]];
stroke(path_join([horiz, vert, -horiz]));
```

--------------------------------

### grid_copies() Function Usage (Getting Matrices)

Source: https://github.com/belfryscad/bosl2/wiki/distributors.scad

Demonstrates how to use grid_copies() as a function to get a list of transformation matrices.

```APIDOC
## grid_copies() Function (Getting Matrices)

### Description
When called as a function, *without* a `p=` argument, returns a list of transformation matrices, one for each copy.

### Synopsis
- mats = grid_copies(spacing, size=, [stagger=], [scale=], [inside=], [axes=]);
- mats = grid_copies(n=, size=, [stagger=], [scale=], [inside=], [axes=]);
- mats = grid_copies(spacing, [n], [stagger=], [scale=], [inside=], [axes=]);
- mats = grid_copies(n=, inside=, [stagger], [scale], [axes=]);

### Arguments
(See Arguments section for module usage. The `p=` argument should not be provided for this usage.)

### Example
(Example not provided in source, but would show the retrieval of transformation matrices.)
```

--------------------------------

### Create a partial ring using points, control points, and ring_width

Source: https://github.com/belfryscad/bosl2/wiki/shapes2d.scad

This example demonstrates creating a partial ring (full=false) using a combination of points, control points (cp), and ring_width.

```openscad
include <BOSL2/std.scad>
ring(32,-2, cp=[1,1], points=[[4,4],[-3,6]], full=false);
```

--------------------------------

### ycyl() Example: By Diameter

Source: https://github.com/belfryscad/bosl2/wiki/shapes3d.scad

Creates a cylinder oriented along the Y axis using diameter. Shows examples with uniform and tapered diameters.

```openscad
include <BOSL2/std.scad>
xdistribute(50) {
    ycyl(l=35, d=20);
    ycyl(l=35, d1=30, d2=10);
}
```

--------------------------------

### Display anchors for a centered wedge

Source: https://github.com/belfryscad/bosl2/wiki/shapes3d.scad

This example demonstrates how to visualize the standard anchors of a wedge when `center=true`. The `show_anchors()` function helps in understanding the positioning points.

```openscad
include <BOSL2/std.scad>
wedge([40, 80, 30], center=true)
    show_anchors(custom=false);
color([0.5,0.5,0.5,0.1])
    cube([40, 80, 30], center=true);
```

--------------------------------

### zcyl() Example: By Diameter

Source: https://github.com/belfryscad/bosl2/wiki/shapes3d.scad

Creates a cylinder oriented along the Z axis using diameter. Shows examples with uniform and tapered diameters.

```openscad
include <BOSL2/std.scad>
xdistribute(50) {
    zcyl(l=35, d=20);
    zcyl(l=35, d1=30, d2=10);
}
```

--------------------------------

### starts_with() Example

Source: https://github.com/belfryscad/bosl2/wiki/strings.scad

Determines if a string begins with a specified pattern. Handles empty patterns correctly by returning true. Returns false if the string is not a string or list.

```openscad
include <BOSL2/std.scad>
b1=starts_with("abcdef","abc");  // Returns true
b2=starts_with("abcdef","def");  // Returns false
b3=starts_with("abcdef","");     // Returns true
```

--------------------------------

### substr()

Source: https://github.com/belfryscad/bosl2/wiki/strings.scad

Returns a substring from a string, starting at a specified position and with a specified length. If length is omitted, it returns the rest of the string from the starting position.

```APIDOC
## substr()

### Description
Returns a substring from a string, starting at a specified position and with a specified length. If length is omitted, it returns the rest of the string from the starting position.

### Synopsis
`newstr = substr(str, [pos], [len]);`

### Parameters
#### Positional Parameters
- `str` (string) - The string to operate on.
- `pos` (integer or vector) - The starting index of the substring. Defaults to 0. Can also be a vector of [first, last] positions.
- `len` (integer) - The length of the substring. If omitted, the rest of the string is returned. If zero or less, an empty string is returned.

### Examples
```
include <BOSL2/std.scad>

s1=substr("abcdefg",3,3);     // Returns "def"
s2=substr("abcdefg",2);       // Returns "cdefg"
s3=substr("abcdefg",len=3);   // Returns "abc"
s4=substr("abcdefg",[2,4]);   // Returns "cde"
s5=substr("abcdefg",len=-2);  // Returns ""
```
```

--------------------------------

### join_prism() with basic attachments

Source: https://github.com/belfryscad/bosl2/wiki/rounding.scad

This example demonstrates the basic usage of join_prism() to create a prism with a flower-shaped profile, attached to a base and an end object, with transformations applied. The linear_sweep function is used to create a secondary object for visualization.

```openscad
include <BOSL2/std.scad>
flower = [for(theta=lerpn(0,360,180,endpoint=false))
          (15+1.3*sin(6*theta))*[cos(theta),sin(theta)]];
join_prism(flower,base=1.4*flower, length=20,
           prism_end_T=yrot(20),aux_T=xrot(10),
           fillet=3, n=25);
linear_sweep(1.4*flower,height=60,center=true,
             convexity=10,orient=RIGHT);
```

--------------------------------

### Create a flat partition path

Source: https://github.com/belfryscad/bosl2/wiki/partitions.scad

Generates a basic flat partition path. Ensure BOSL2 std library is included.

```openscad
include <BOSL2/std.scad>
stroke(partition_path(["flat"]), width=3);
```

--------------------------------

### Start Cubic Bezier Segment

Source: https://github.com/belfryscad/bosl2/wiki/CheatSheet

Constructs the control points for the start of a cubic Bezier segment. Can use absolute points or vectors for direction and radius.

```openscad
pts = [bez_begin](beziers.scad#function-bez_begin)(pt, a, r, [p=]);
```

```openscad
pts = [bez_begin](beziers.scad#function-bez_begin)(pt, VECTOR, [r], [p=]);
```

--------------------------------

### Create a basic arc segment

Source: https://github.com/belfryscad/bosl2/wiki/drawing.scad

This example demonstrates creating a basic arc segment using radius and angle. The `wedge=true` parameter creates a pie slice shape.

```openscad
include <BOSL2/std.scad>
arc(r=30, angle=30, wedge=true);
```

--------------------------------

### Create Trapezoidal Threaded Nut (Blunt Start)

Source: https://github.com/belfryscad/bosl2/wiki/threading.scad

Generates a trapezoidal threaded nut with a blunt start to the threads. Set `blunt_start=false` to disable this feature.

```openscad
include <BOSL2/std.scad>
include <BOSL2/threading.scad>
trapezoidal_threaded_nut(nutwidth=17.4, id=10, h=10, pitch=2, starts=3, $fa=1, $fs=1, $slop=0.15, blunt_start=false);
```

--------------------------------

### Threaded rod with blunt start disabled

Source: https://github.com/belfryscad/bosl2/wiki/threading.scad

Generates a threaded rod where the blunt start feature is explicitly disabled. Requires including std.scad and threading.scad.

```openscad
include <BOSL2/std.scad>
include <BOSL2/threading.scad>
threaded_rod(d=25, l=20, pitch=2, $fa=1, $fs=1, blunt_start=false);
```

--------------------------------

### Create a Worm Gear with Multiple Starts

Source: https://github.com/belfryscad/bosl2/wiki/gears.scad

Generates a worm gear designed to mesh with a worm having multiple starts. Adjust the 'worm_starts' parameter accordingly.

```openscad
include <BOSL2/std.scad>
include <BOSL2/gears.scad>
worm_gear(circ_pitch=5, teeth=36, worm_diam=30, worm_starts=4);
```

--------------------------------

### prismoid() Example 10: Specifying top, height and angle

Source: https://github.com/belfryscad/bosl2/wiki/shapes3d.scad

Demonstrates specifying the top dimensions, height, and asymmetric X/Y angles.

```openscad
include <BOSL2/std.scad>
prismoid(size2=[100,75], h=30, xang=[50,60], yang=[70,40]);
```

--------------------------------

### line_copies() with start and end points

Source: https://github.com/belfryscad/bosl2/wiki/distributors.scad

Distributes copies between two specified points (p1 and p2). Use when the exact start and end locations are critical.

```OpenSCAD
include <BOSL2/std.scad>
line_copies(p1=[0,0,0], p2=[5,5,20], n=6) cuboid([3,2,1]);
```

--------------------------------

### Install BOSL2 on Fedora

Source: https://github.com/belfryscad/bosl2/blob/master/README.md

Use this command to install the BOSL2 library on Fedora Linux. Note that the repository version might be older than the latest release.

```bash
sudo dnf install openscad-bosl2
```

--------------------------------

### Demonstrate All UTS Screw Head Types (Fast Preview)

Source: https://github.com/belfryscad/bosl2/wiki/screws.scad

Provides a comprehensive demonstration of all available head types for UTS screws. Uses `thread=0` for a faster preview, making it ideal for quickly visualizing head geometry. Anchored to the top for consistent placement.

```openscad
include <BOSL2/std.scad>
include <BOSL2/screws.scad>
xdistribute(spacing=15){
  ydistribute(spacing=15){
     screw("1/4", thread=0,length=8, anchor=TOP, head="none", drive="hex");
     screw("1/4", thread=0,length=8, anchor=TOP, head="none", drive="torx");
     screw("1/4", thread=0,length=8, anchor=TOP, head="none", drive="slot");
     screw("1/4", thread=0,length=8, anchor=TOP, head="none");
  }
  screw("1/4", thread=0, length=8, anchor=TOP, head="hex");
  ydistribute(spacing=15){
     screw("1/4", thread=0,length=8, anchor=TOP, head="socket", drive="hex");
     screw("1/4", thread=0,length=8, anchor=TOP, head="socket", drive="torx");
     screw("1/4", thread=0,length=8, anchor=TOP, head="socket");
  }
  ydistribute(spacing=15){
     screw("1/4", thread=0,length=8, anchor=TOP, head="socket ribbed", drive="hex",$fn=32);
     screw("1/4", thread=0,length=8, anchor=TOP, head="socket ribbed", drive="torx",$fn=32);
     screw("1/4", thread=0,length=8, anchor=TOP, head="socket ribbed",$fn=24);
  }
  ydistribute(spacing=15){
     screw("1/4", thread=0,length=8, anchor=TOP, head="button", drive="hex");
     screw("1/4", thread=0,length=8, anchor=TOP, head="button", drive="torx");
     screw("1/4", thread=0,length=8, anchor=TOP, head="button");
  }
  ydistribute(spacing=15){
     screw("1/4", thread=0,length=8, anchor=TOP, head="round", drive="slot");
     screw("1/4", thread=0,length=8, anchor=TOP, head="round", drive="phillips");
     screw("1/4", thread=0,length=8, anchor=TOP, head="round");
  }
  ydistribute(spacing=15){
     screw("1/4", thread=0,length=8, anchor=TOP, head="pan", drive="slot");
     screw("1/4", thread=0,length=8, anchor=TOP, head="pan", drive="phillips");
     screw("1/4", thread=0,length=8, anchor=TOP, head="pan");
  }
  ydistribute(spacing=15){

```

--------------------------------

### prismoid() Example 7: Right Prism

Source: https://github.com/belfryscad/bosl2/wiki/shapes3d.scad

Demonstrates creating a right prism by setting the top size to zero.

```openscad
include <BOSL2/std.scad>
prismoid(size1=[30,60], size2=[0,60], shift=[-15,0], h=30);
```

--------------------------------

### Example: Gear Shortening Restores Clearance

Source: https://github.com/belfryscad/bosl2/wiki/gears.scad

This example demonstrates how applying the `gear_shorten` factor restores the normal tooth clearance between two profile-shifted spur gears.

```openscad
include <BOSL2/std.scad>
include <BOSL2/gears.scad>
teeth1=25;
teeth2=19;
mod=4;
ps1 = 0.75;
ps2 = 0.75;
d = gear_dist(mod=mod, teeth1,teeth2,0,ps1,ps2);
shorten=gear_shorten(teeth1,teeth2,0,ps1,ps2);
color("lightblue")
  spur_gear2d(mod=mod,teeth=teeth1,profile_shift=ps1,shorten=shorten,gear_spin=-90);
right(d)
  spur_gear2d(mod=mod,teeth=teeth2,profile_shift=ps2,shorten=shorten,gear_spin=-90);
```

--------------------------------

### Create a ring segment with specified start and end angles

Source: https://github.com/belfryscad/bosl2/wiki/shapes2d.scad

Use the angle parameter to define a segment of a ring by specifying start and end angles in degrees.

```openscad
include <BOSL2/std.scad>
ring(r1=5,r2=7, angle=[33,110], n=32);
```

--------------------------------

### OpenSCAD Description Block Example

Source: https://github.com/belfryscad/bosl2/blob/master/WRITING_DOCS.md

Shows a multi-line Description block for providing detailed explanations of code functionality.

```openscad
// Description:
//   This is a description.
//   It can be multiple lines in length.
```

--------------------------------

### rot_copies() with translation and start angle

Source: https://github.com/belfryscad/bosl2/wiki/distributors.scad

Illustrates creating 6 rotated copies with a translation and a starting angle (sa=45). Use this to control the initial orientation of the copies.

```OpenSCAD
include <BOSL2/std.scad>
rot_copies(n=6, v=UP+FWD, delta=[10,0,0], sa=45)
    yrot(90) cylinder(h=20, r1=5, r2=0);
color("red",0.333) yrot(90) cylinder(h=20, r1=5, r2=0);
```