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PR-CAD: Progressive Refinement for Unified Controllable and Faithful Text-to-CAD Generation with Large Language Models

▲ 55 points 17 comments by PaulHoule 7h ago HN discussion ↗

Pangram verdict · v3.3

We believe that this document is fully human-written

8 %

AI likelihood · overall

Human
100% human-written 0% AI-generated
SEGMENTS · HUMAN 1 of 1
SEGMENTS · AI 0 of 1
WORD COUNT 226
PEAK AI % 8% · §1
Analyzed
Jun 9
backend: pangram/v3.3
Segments scanned
1 windows
avg 226 words each
Distribution
100 / 0%
human / AI fraction
Verdict
Human
Pangram v3.3

Article text · 226 words · 1 segments analyzed

Human AI-generated
§1 Human · 8%

View PDF HTML (experimental) Abstract:The construction of CAD models has traditionally relied on labor-intensive manual operations and specialized expertise. Recent advances in large language models (LLMs) have inspired research into text-to-CAD generation. However, existing approaches typically treat generation and editing as disjoint tasks, limiting their practicality. We propose PR-CAD, a progressive refinement framework that unifies generation and editing for controllable and faithful text-to-CAD modeling. To support this, we curate a high-fidelity interaction dataset spanning the full CAD lifecycle, encompassing multiple CAD representations as well as both qualitative and quantitative descriptions. The dataset systematically defines the types of edit operations and generates highly human-like interaction data. Building on a CAD representation tailored for LLMs, we propose a reinforcement learning-enhanced reasoning framework that integrates intent understanding, parameter estimation, and precise edit localization into a single agent. This enables an "all-in-one" solution for both design creation and refinement. Extensive experiments demonstrate strong mutual reinforcement between generation and editing tasks, and across qualitative and quantitative modalities. On public benchmarks, PR-CAD achieves state-of-the-art controllability and faithfulness in both generation and refinement scenarios, while also proving user-friendly and significantly improving CAD modeling efficiency.

Subjects: Computation and Language (cs.CL); Artificial Intelligence (cs.AI) Cite as: arXiv:2604.19773 [cs.CL]   (or arXiv:2604.19773v1 [cs.CL] for this version)   https://doi.org/10.48550/arXiv.2604.19773 arXiv-issued DOI via DataCite Submission history From: Jiyuan An [view email] [v1] Fri, 27 Mar 2026 12:13:20 UTC (10,655 KB)