OSCADml_ml

In conjunction with OCADml, this library provides an OCaml front-end to the OpenSCAD solid modelling language. All SCAD primitives and transformation functions are made available.

Notable differences from the OpenSCAD language

• Angles are represented in radians (and converted to degrees when compiling to OpenSCAD).
• linear_extrude and rotate_extrude have been renamed to extrude and revolve
• The dimensional system (2D or 3D) each shape inhabits is tracked by the type system. This is used to restrict the operations that can be legally applied (e.g. 2D shapes cannot be moved off of the xy plane, Scad.extrude can only be applied to 2D shapes) and enforcing non-mixing of 2D and 3D shapes during boolean operations.

Usage

open OCADml
open OSCADml

let () =
  let scad_logo =
    let rad = 5.
    and fn = 720 in
    let cyl = Scad.cylinder ~fn ~center:true ~height:(rad *. 2.3) (rad /. 2.) in
    let cross_cyl = Scad.rotate (v3 0. (Float.pi /. 2.) 0.) cyl in
    Scad.union
      [ Scad.difference
          (Scad.sphere ~fn rad)
          [ cyl; cross_cyl; Scad.rotate (v3 0. 0. (Float.pi /. 2.)) cross_cyl ]
      ; Scad.color ~alpha:0.25 Color.Magenta cross_cyl
      ]
  in
  Scad.to_file "scad_logo.scad" scad_logo

Generated .scad scripts can then be viewed with the OpenSCAD viewer as you normally would, or directly exporting Scad.t into other model formats or PNGs with Scad.export and Scad.snapshot respectively.

API

OSCADml -- top level library interface

Core DSL

• Scad -- well-typed dimension aware OpenSCAD models
• Text -- Scad.text configuration types
• Color -- Scad.color configuration type

Utilities

• Export -- exporting .scad scripts via OpenSCAD CLI
• Debug -- helpers for simple viewing of OCADml types

OCADml documentation

The OCADml library features prominently in the following examples, infact they can largely be considered part of OCADml's extended documentation. Thus in working through them, as well as using OSCADml, the OCADml documentation should serve as a helpful reference.

Examples

Paths and Sweeps

• Offset and roundovers
• Default vs euler path transformation reference
• Bespoke sweep transforms (with direct affine transform generation)
• Cubic spline
• Arcing paths
• Helical paths and extrusions
• Path resampling and scaling/twisting sweeps

Rounded Extrusions

• Rounded sweeps
• Continuous curvature rounded prisms
• Rounded extrusion of cairo imported polygonal font

Skins and Morphs

• Profile skinning
• Morphing sweeps and extrusions

Function Plotting

• Rose polar plot
• Cartesian gravity well
• Axial chalice

[@@deriving cad]

There is a companion ppx, [@@deriving cad] for generating transformation functions for user-defined records and abstract types made up of the Scad.t, along with their corresponding vector (V2.t or V3.t) types (and those composed of them) provided in by OCADml.

Generating models on write

For a more pleasant modelling experience, it is highly recommended to setup dune to automate writing your models to file whenever the source files are saved. To do so, add a dune rule that runs your projects executable after it is built. For example, in your_project/bin/dune:

(executable
 (public_name your_project)
 (name main)
 (libraries OCADml OSCADml))

(rule
 (alias model)
 (action
  (run your_project)))

Then start dune in watch mode with dune build -w @model.