DPI Bypass Detect

Built for Dungeon Train — usable by any mod. Dungeon Train uses DPI Bypass Detect to explain, on the title screen, why its online features may not be loading. DPI Bypass Detect has no dependency on Dungeon Train.

Why it exists

Players behind national internet filtering often run tools like zapret or GoodbyeDPI to reach Discord and YouTube. Some of their settings also rewrite a mod's own web requests, so its online features quietly fail with no error. Knowing the tool is running lets a mod tell the player what's going on in one sentence.

What it does

DPI Bypass Detect is a small library mod. On its own it does nothing you can see. Another mod asks it one question — is a DPI-bypass tool running? — and decides what, if anything, to show.

What it looks at, and what it doesn't

• It only checks for these exact program names: winws.exe (zapret), goodbyedpi.exe, zapret.exe.
• Windows only. Those tools only exist on Windows, so on macOS and Linux it doesn't look at all.
• No command lines, window titles, files, registry, network access or admin rights.
• The answer never leaves your PC. The only trace is one line in the game log.
• It checks once per game session, only when another mod asks.

Setup

Nothing to configure. Client-side only; servers don't need it.

For mod developers

games.brennan.dpibypassdetect.api.DpiBypassDetect — detectNow() (call off the render thread; cached after the first call) and hasResult(). Declare it as an optional dependency and guard calls with your loader's "is mod loaded" check. Launch with -Ddpibypassdetect.test=winws.exe to test your UI without the tool.

Compatibility

Fabric, Forge and NeoForge for Minecraft 1.21.1. No mixins, items, blocks, commands or config.