Understanding the Challenges of OpenSCAD Users for 3D Printing

TL;DR

The paper investigates why users choose programming-based CAD (notably OpenSCAD) for 3D printing, and what obstacles they face. Through twenty semi-structured interviews plus a hands-on task, it identifies motivations centered on parametric control and precision, while detailing challenges in linking code to the 3D view, performing spatial transformations, and designing organic curves. Key contributions include a qualitative, theme-based portrait of OpenSCAD users, a nuanced account of design and fabrication workflows, and actionable directions for improving programming-based CAD (e.g., view-code coupling, spatial manipulators, and bidirectional programming). The findings offer practical insights for tool developers and educators aiming to lower entry barriers and enhance 3D printing outcomes with code-centric CAD.

Abstract

Direct manipulation has been established as the main interaction paradigm for Computer-Aided Design (CAD) for decades. It provides fast, incremental, and reversible actions that allow for an iterative process on a visual representation of the result. Despite its numerous advantages, some users prefer a programming-based approach where they describe the 3D model they design with a specific programming language, such as OpenSCAD. It allows users to create complex structured geometries and facilitates abstraction. Unfortunately, most current knowledge about CAD practices only focuses on direct manipulation programs. In this study, we interviewed 20 programming-based CAD users to understand their motivations and challenges. Our findings reveal that this programming-oriented population presents difficulties in the design process in tasks such as 3D spatial understanding, validation and code debugging, creation of organic shapes, and code-view navigation.

Figures (1)

• Figure 1: Example of two parametric CAD applications.