ZW3D Ports 12M-Line C++ to HarmonyOS: 90% Faster Load, 68% Less Debug Memory

Background: A 12-Million-Line Industrial CAD Codebase

ZW3D (中望 3D) is a long-standing domestic CAD/CAM/CAE suite that has led the Chinese market for over a decade. Its flagship version, ZW3D Wukong 2027, contains approximately 12 million lines of C++ code and is built on the self-developed ZGS 3D geometric constraint engine. The software powers high-end equipment such as CSIC Power's M390 generator series (tens of thousands of parts) and consumer electronics like Skyworth's A5F Pro AI TV (500+ parts, nearly 3,000 design features on the back panel alone). This scale demonstrates ZW3D's ability to handle extreme assembly complexity and precision modeling.

Challenge: Migrating a Massive C++ Project to HarmonyOS

Historically rooted in the Windows ecosystem, ZW3D faced industry-wide hurdles when moving to the HarmonyOS development environment: excessively long project load and compile times, and high memory consumption during debugging. These bottlenecks are typical for ultra-large C++ codebases and severely impact developer productivity.

Collaborative Optimization: ZWSOFT and DevEco Studio Teams

The ZWSOFT R&D team partnered closely with the DevEco Studio toolchain team to target the three most frequent development scenarios — code editing, debugging, and compilation — optimizing from the bottom-up: toolchain, indexing logic, and compilation architecture.

Code Editing: Multi-Level Indexing Cuts Load Time by Over 90%

To address index bloat and resource-scanning stalls, DevEco Studio introduced the BiFang (毕方) multi-level indexing mechanism. It supports on-demand switching of index levels, balancing precision and speed, and adds a resource-filter configuration to exclude large, unnecessary test resources with one click.

Result: Project startup-to-usable time dropped from 27 minutes to 2 minutes 30 seconds — a 90%+ speedup . Developers no longer endure half-hour waits before coding.

Debugging: LLDB Restructuring Reduces Peak Memory by 68%

The team rewrote the LLDB debugging logic to eliminate redundant debug information and adopt on-demand loading. Combined with a persistent debug server and incremental update capability, this solved latency and stutter issues.

Result: Peak debug memory fell from 22 GB to 7 GB ( 68%+ reduction ). First breakpoint hit and incremental package push are both kept under 10 seconds, delivering smooth debugging even for massive projects.

Compilation: BiSheng Compiler with AST Persistence and Function-Level Incremental Builds

Leveraging HarmonyOS's cross-toolchain advantages, the BiSheng (毕昇) compiler was integrated. It persists header-file ASTs and performs function-level incremental compilation, pushing optimization granularity to the limit.

Result: Full compilation time decreased from 35 minutes to 30 minutes; incremental compilation shrank from 13.5 seconds to 10 seconds.

Mutual Empowerment: Industrial Software + HarmonyOS Ecosystem

The ZW3D Wukong 2027 HarmonyOS adaptation is in its final stages. The ZGS geometric engine achieves 100% independent control, and core capabilities — modeling, assembly, rendering — fully match mainstream desktop counterparts. The version is slated for release on the HarmonyOS App Store in August 2026 for commercial use.

From initial adaptation friction to today's seamless million-line engineering experience, DevEco Studio — powered by BiFang and BiSheng key technologies — has continuously refined details: NDK builds, code formatting, sub-process debugging, error lookup, and more, collectively boosting ultra-large C++ development efficiency.

Industry Outlook: HarmonyOS Accelerates Domestic Industrial Software Substitution

The rise of domestic industrial software is not a slogan but a systemic breakthrough across the entire toolchain and ecosystem. ZW3D's successful landing on HarmonyOS marks a milestone collaboration between a leading domestic industrial software vendor and a sovereign operating system. It proves both the hard-core strength of Chinese industrial software and DevEco Studio's readiness to carry commercial-grade, ten-million-line projects.

As the HarmonyOS ecosystem expands, more heavyweight industrial applications will complete adaptation. Backed by DevEco Studio's integrated toolchain capabilities, HarmonyOS will deepen its focus on enterprise-grade development scenarios, empowering the domestic software-hardware ecosystem and accelerating the substitution process, jointly building a self-reliant foundation for industrial software.