Yexiang Zhou – Yexiang Zhou

2026

Submit-tool-mod: a fork of Unreal’s SubmitTool with an OpenProject integration

Epic’s SubmitTool takes over a Perforce changelist and runs a set of checks before it lets you press Submit. This fork replaces its Jira integration with a native OpenProject one, fixes a red error line at startup, and carries the procedure that gets the tool onto every workstation through UnrealGameSync.

September 7, 2026

Tech

Horde-extension: notifications and OpenProject issues for Epic’s Horde

Two plugins for Epic’s Horde build server. One tells the people involved by Mattermost DM and email when a job finishes or CI breaks; the other replaces Horde’s built-in Jira integration with a two-way OpenProject one. Both mount into the stock container, and the image is never modified.

September 7, 2026

Tech

Indie studio infra stack: self-hosted infrastructure for a small Unreal team

Sixteen services on one host under one domain – Perforce, Helix Swarm, Horde, GitLab, Mattermost, Outline, OpenProject, mail and a VPN – all signed in to with one authentik account. The whole deployment is one directory tree, rendered from a single file that says who your studio is.

September 7, 2026

Tech

2024

Action Game Combat Design

A combat design practice finished within one week, delivered as a playable Unity demo. An easy-to-learn action framework for casual players – interrupt levels, an energy and anger resource loop, input windows and readability cues, behavior-tree enemies sharing an aggression token pool. Full design document, gameplay video and Windows build.

November 11, 2024

Design

Game AI from Scratch: Steering, Pathfinding and Behavior Trees in C++

Steering behaviors, Dijkstra and A*, and a multithreaded behavior tree, written in C++ on openFrameworks with no game engine underneath. With animated demos, a janitor-robot example and a downloadable Windows build.

February 3, 2024

Tech

2023

Redesigned Intro of The Division 2: A Level Design Practice

A level design test finished within three days. The level redesigns the intro of Tom Clancy’s The Division 2 to teach the basic key elements of the game in three beats with a rising dramatic curve. The full level design document (AI behavior trees, stats, blockouts, top-down maps, gameplay flow) and a blockout walkthrough video.

June 5, 2023

Design

My DOOM Campaign: Dive into Hell

A DOOM SnapMap campaign level with 20-40 minutes of single-player gameplay, built in three parts – learn each weapon against the enemies it answers, practice combining them in larger spaces, then survive a four-stage final arena. Full playthrough video, level flow, and Object Mode plus Blueprint Mode views of all seven sublevels.

May 8, 2023

Design

2022

My 2D Game Engine

A small 2D game engine written in C++ from scratch – game loop and bootstrapper, vector and matrix math with SSE, a reference-counted smart pointer, a data-driven game object factory, a job system with worker threads, and render, physics and swept-AABB collision systems. Built and captured again for this article.

May 1, 2022

Tech

2021

Heap Memory Manager: Custom malloc/free and new/delete in C++

A small memory system in C++ that replaces malloc/free and new/delete. A general allocator carves blocks from the end of the heap and merges free blocks back together; three fixed-size allocators handle small allocations with a bit array and _BitScanForward. Written as a course final exam.

December 18, 2021

Tech

Dark Winter: Designing a Survival Board Game

A four-player cooperative board game about surviving a pandemic collapse in one house. The core loop is deliberate positive feedback – every recovery costs resources, and resources only come from characters who are still in shape. Full rules, the three playtests that reshaped them, and my own analysis of why the small mechanics carry the experience.

March 4, 2021

Design