mobium-perf

Mobium

Faster chests, signs and mobs: Mobium draws things that stand still from GPU buffers and lets the GPU write animated
models’ vertices, instead of the CPU rebuilding them every frame.

Mobium is a client-side performance mod for Minecraft (Fabric, Quilt and NeoForge). Vanilla, Iris and Entity Model
Features still decide how everything looks: Mobium changes how geometry reaches the GPU, never what ends up on screen.

⚡ Performance

Average FPS on a laptop with Intel Arc 140V graphics, Sodium, 1920×1080. The more chests, signs, item frames and mobs
are on screen, the more Mobium gains; an empty field gets neither faster nor slower.

📊 Benchmarks wanted

These numbers come from one laptop. To find out how Mobium does on other hardware, we need your results. The
benchmark builds its own scenes, so results from different computers compare, and it takes about six minutes:

1. Create a new world: in the World tab set World Type to Superflat and the seed to mobium, and under
   More → Data Packs move Mobium Benchmark to the selected packs.
2. Type /mobium benchmark and leave the game alone until the result shows in chat. It measures a storage room and
   mob pens with Mobium off and on, and puts your settings back at the end.
3. Send us the file it names (in mobium-bench in your game folder; click the name in chat to open the folder): drop
   it in our Discord server or attach it to a
   benchmark report on GitHub.

The file already names your CPU, GPU, mods, shader pack and screen. The data pack is off in every other world, so the
scenes are only ever built in this one.

✨ Features

Static cache

Things that stand still are captured once through the game’s own rendering code, resource packs and other mods’
changes included, and from then on drawn from GPU buffers instead of being rebuilt every frame. As soon as something
changes, Mobium captures it again.

• Chests of all kinds and shulker boxes
• Signs and hanging signs, with their text
• Skulls and heads, decorated pots, shelves
• Item frames, armor stands without armor, item and block displays

While a chest opens, a pot wobbles or anything else moves, the game draws it as usual.

GPU part transform

Mobs, armor, banners and everything else built from model parts are still posed and animated by the game, Entity Model
Features and Fresh Animations. Only the last step moves: instead of the CPU writing every corner of every cube, a
shader on the GPU writes exactly the same vertices, also in Iris’s shader pack formats. Mobium checks this on your GPU
and lets the game draw as usual should a graphics driver ever disagree.

The gain is largest where writing vertices is expensive: many mobs, Fresh Animations or a shader pack. With only a few
mobs on screen it can cost slightly more than it saves, which shows only at several hundred FPS. It needs OpenGL 4.3
(current Windows and Linux drivers; not macOS).

Coming later

• Animation LOD (optional): far-away mobs reuse last frame’s pose.
• Vulkan support.

📖 Usage

Mobium works out of the box.

• Settings: Mod Menu (Fabric), the mods list (NeoForge) or Mobium’s page in Sodium’s video settings, with a switch
  for every cached type.
• A/B key: switches Mobium off and on live, to compare in the same spot. It is the key right of <kbd>P</kbd>:
  <kbd>]</kbd> on a US keyboard, <kbd>+</kbd> on a German one.
• F3: the debug entries mobium:modules and mobium:timings show what Mobium does and where the frame time goes.
• /mobium benchmark: measures Mobium off and on in a world made with the Mobium Benchmark data pack (see above).

If something goes wrong inside Mobium, it switches the affected part off, shows one message and lets the game draw as
usual.

🧩 Compatibility

❓ FAQ

Do I need to install Mobium on the server?

No. Mobium is client-side only and works in singleplayer and on any server.

Does Mobium change how things look?

It must not. Automated test scenes compare Mobium’s picture pixel by pixel with the game’s own. If you see a
difference, press the A/B key to check whether it goes away with Mobium off, and please report it, ideally with a
screenshot taken with Mobium on and one with it off.

Does Mobium work with Vulkan?

Not yet. Mobium needs OpenGL, the game’s default renderer; on Vulkan it stays off and the game draws everything itself.
Vulkan support is planned.

💬 Support

If you need help with any of my mods, join my Discord server, or open an issue on
GitHub.