openscad_attachable_text3d

OpenSCAD module for creating blocks of 3D text that are attachable with BOSL2.

The openscad_attachable_text3d library marries BOSL2 bi-directional attachability and fontmetrics.scad-measured text dimensions into a set of modules that produce attachable 3D text: that is, modeled 3D objects that can use BOSL2's attachments functionality to join text to other text, arbitrary shapes, or existing attachment-aware models, by using pre-measured font dimensions as sizing data.

OpenSCAD provides a rudimentary text() built-in function, but only for 2D models. BOSL2 takes that a step further, and provides a text3d() module, and those models may be attached to other BOSL2 attachable primatives. This attachability limitation is because post hoc dimension information of models within OpenSCAD is not available, and BOSL2 leverages the built-in text() to create text3d() models. The fontmetrics library has fairly accurate per-character dimensions for a variety of font faces and styles.

attachable_text3d() uses fontmetrics to measure the text to build, then builds it with BOSL2, and returns a fully attachable model.

Use & Examples

This project's wiki has examples and details on implementation, as well as inline reference SCAD documentation.

include <attachable_text3d.scad>

attachable_text3d("Hello") 
    show_anchors();

Installation

1. Download the most recent release of openscad_attachable_text3d from https://github.com/jon-gilbert/openscad_attachable_text3d/releases/latest
2. Unpack the zipfile or tarball. Inside will be a directory, named openscad_attachable_text3d-0.8 (where 0.8 is the version of the release). Extract that folder to your OpenSCAD library directory
3. Rename that release directory from openscad_attachable_text3d-0.8 to just openscad_attachable_text3d

Details on installation of this library can be found here, including notes on dependencies.

Required Libraries

You'll need the BOSL2 framework to get this working; see https://github.com/BelfrySCAD/BOSL2/ for instructions on how to download and incorporate it.

fontmetrics & fontmetricsdata

The fontmetrics and fontmetricsdata SCAD libraries are by Alexander Pruss, licensed under CC-BY-4.0. They're redistributed within openscad_attachable_text3d, here.

fontmetrics changes

The fontmetrics.scad library this project depends on has a minor bug in its library. It's easily rectified, as detailed below:

At line 27 of the fontmetrics.scad library, a function _isString() is defined that compares v with an empty string, "". This breaks under certain circumstances. A more thorough, safer implementation is to use OpenSCAD's built-in is_string() function (available as of their 2019.05 release). You can make that change directly into fontmetrics.scad as such:

27c27
< function _isString(v) = v >= "";
---
> function _isString(v) = is_string(v);

This release of openscad_attachable_text3d has the _isString() fix applied.

Author & License

This library is copyright 2023 Jonathan Gilbert jong@jong.org, and released for use under the MIT License.