PLLM: Pseudo-Labeling Large Language Models for CAD Program Synthesis

2026-02-13

Technology Category

Natural Language Processing: Code Generation / Program Synthesis from Natural LanguageComputer Vision: 3D Computer VisionMachine Learning: Deep Generative Models & Autoencoders

Application Category

Semantics and Knowledge: Methods to enhance, augment, integrate or synergize semantic models such as knowledge graphs and LLMsEconomics, Online Markets and Human Computation: Data quality aspects of human-annotated datasetsSearch and Retrieval-Augmented AI: Large language models for search

Abstract

Recovering Computer-Aided Design (CAD) programs from 3D geometries is a widely studied problem. Recent advances in large language models (LLMs) have enabled progress in CAD program synthesis, but existing methods rely on supervised training with paired shape-program data, which is often unavailable. We introduce PLLM, a self-training framework for CAD program synthesis from unlabeled 3D shapes. Given a pre-trained CAD-capable LLM and a shape dataset, PLLM iteratively samples candidate programs, selects high-fidelity executions, and augments programs to construct synthetic program-shape pairs for fine-tuning. We experiment on adapting CAD-Recode from DeepCAD to the unlabeled ABC dataset show consistent improvements in geometric fidelity and program diversity.

Problem

• CAD program synthesis
• unlabeled 3D shapes
• pseudo-labeling
• program recovery
• geometric reconstruction

Innovation

• pseudo-labeling
• self-training
• CAD program synthesis
• large language models
• unlabeled 3D shapes