CAD-Coder: An Open-Source Vision-Language Model for Computer-Aided Design Code Generation

TL;DR

CAD-Coder is an open-source vision-language model that generates editable CAD code from images, outperforming existing models and demonstrating promising generalization to real-world images, thus streamlining engineering design workflows.

Contribution

Introduces CAD-Coder, a fine-tuned vision-language model for CAD code generation with a new large dataset, achieving superior accuracy and generalization over prior models.

Findings

Achieves 100% valid syntax rate in CAD code generation.

Outperforms state-of-the-art models like GPT-4.5 and Qwen2.5-VL-72B.

Shows potential to generate CAD code from real-world images.

Abstract

Efficient creation of accurate and editable 3D CAD models is critical in engineering design, significantly impacting cost and time-to-market in product innovation. Current manual workflows remain highly time-consuming and demand extensive user expertise. While recent developments in AI-driven CAD generation show promise, existing models are limited by incomplete representations of CAD operations, inability to generalize to real-world images, and low output accuracy. This paper introduces CAD-Coder, an open-source Vision-Language Model (VLM) explicitly fine-tuned to generate editable CAD code (CadQuery Python) directly from visual input. Leveraging a novel dataset that we created--GenCAD-Code, consisting of over 163k CAD-model image and code pairs--CAD-Coder outperforms state-of-the-art VLM baselines such as GPT-4.5 and Qwen2.5-VL-72B, achieving a 100% valid syntax rate and the highest accuracy in 3D solid similarity. Notably, our VLM demonstrates some signs of generalizability, successfully generating CAD code from real-world images and executing CAD operations unseen during fine-tuning. The performance and adaptability of CAD-Coder highlights the potential of VLMs fine-tuned on code to streamline CAD workflows for engineers and designers. CAD-Coder is publicly available at: https://github.com/anniedoris/CAD-Coder.