ImmediatelyFast in All the Mons

ImmediatelyFast is a client-side performance mod. It speeds up what Minecraft calls immediate mode rendering, which is a big part of how the game draws things on your screen every frame. It's built to be lightweight and to play nicely with other mods.^[1]

This pack ships ImmediatelyFast 1.6.13 for Minecraft 1.21.1 on NeoForge. It has been part of the pack since 0.3.0-beta or earlier.^[2]

What it speeds up

The mod uses a custom buffer implementation that batches draw calls and uploads data to the GPU more efficiently. That general optimization covers these areas:^[1]

• Entities^[1]
• Block entities^[1]
• Particles^[1]
• Text rendering^[1]
• GUI and HUD^[1]
• Immediate mode rendering done by other mods^[1]

It also replaces some vanilla rendering code with faster versions, specifically for map rendering, HUD rendering and text rendering.^[1]

Compatibility and config

The mod aims to interfere with other mods as little as possible and should work with most modpacks. Its known incompatibilities are OptiFabric/OptiFine and most closed source clients such as LunarClient and LabyMod.^[1]

It has a config file in the config folder of your instance. Most options are best left at their defaults, but a few can be tweaked for performance or compatibility. For example, if you see problems with HUD elements, the author suggests turning off the hud_batching optimization.^[1]

Same as in the All the Mods 10 8.1 guide

Good news: there's nothing to craft or set up first. ImmediatelyFast is a rendering optimization mod. It improves the immediate mode rendering performance of the client and is designed to be lightweight and compatible with other mods.^[1]

Unverified I couldn't confirm any items, recipes or quests for this mod in this pack, so there is no crafting order to follow and no recipe blocks to show.

What it speeds up

The mod uses a custom buffer implementation that batches draw calls and uploads data to the GPU more efficiently. That applies to these areas:^[1]

• Entities and block entities^[1]
• Particles^[1]
• Text rendering^[1]
• The GUI and HUD^[1]
• Immediate mode rendering from other mods^[1]

It also replaces some vanilla code with faster versions, specifically for map rendering, HUD rendering and text rendering.^[1]

What to expect

The mod only helps when your CPU is the bottleneck. That is most likely the case unless your GPU is ancient or you run very heavy shaders. Slower CPUs benefit more than really fast ones.^[1]

The mod's author reports the biggest gains in busy scenes: roughly 2x higher FPS with many entities or many signs around you, and roughly 5x higher with many maps on screen. Those figures were measured with older mod versions on Minecraft 1.19.3, not in this pack, so treat them as a rough guide to where the mod helps rather than what you'll see here.^[1]

Same as in the All the Mods 10 2.11 guide

ImmediatelyFast doesn't have machines, multiblocks, power or pipes. It's an open source performance mod that works entirely on the rendering side of your client. Its job is to make immediate mode rendering faster. That's the part of the game that draws things like mobs, chests, particles, text and your HUD every frame. It's designed to be lightweight and to play nicely with other mods.^[1]

How the batching works

The core trick is a custom buffer implementation. Normally the game sends many small draw calls. ImmediatelyFast batches those draw calls together and uploads data to your GPU more efficiently. This applies to immediate mode rendering in general, so it helps a whole range of things at once.^[1]

• Entities, such as mobs and animals.^[1]
• Block entities, such as chests.^[1]
• Particles.^[1]
• Text rendering.^[1]
• The GUI and HUD.^[1]
• Immediate mode rendering done by other mods, so modded blocks and entities can benefit too.^[1]

Targeted optimizations

On top of the general batching, ImmediatelyFast changes some vanilla rendering code to use a more efficient implementation. According to the mod page, these targeted changes cover three areas: map rendering, HUD rendering and text rendering. If you have a wall full of maps or a busy HUD, these are the parts doing the heavy lifting.^[1]

When you'll actually notice it

ImmediatelyFast can only raise your FPS when your CPU is the bottleneck. The mod page says this is most likely the case unless your GPU is very old or you run very heavy shaders. Slower CPUs benefit more than really fast ones. If you already have plenty of CPU headroom, you may not see much change.^[1]

The mod page's own benchmarks show the biggest gains in scenes packed with entities, maps, signs or HUD elements. For example, it expects around 2x higher FPS on busy servers with lots of entities and around 5x higher when many maps are on screen. Keep in mind that these tests were run on ImmediatelyFast 1.1.1 and 1.1.7 on Minecraft 1.19.3, not on the version in this pack. Treat them as a rough idea of where the mod helps, not as numbers you'll get here.^[1]

Compatibility

ImmediatelyFast is built to interfere with other mods as little as possible and should work with most mods and modpacks. The mod page lists OptiFabric and OptiFine as known incompatibilities, along with most closed source clients like LunarClient and LabyMod.^[1]

Config options

The mod has a config file in your instance's config folder. The mod page says most options should be left at their defaults, but some can be tweaked for performance or compatibility.^[1]

• font_atlas_resizing makes the font atlas textures larger, which helps with high resolution or custom server fonts.^[1]
• map_atlas_generation puts map textures into a single texture instead of many, which helps when lots of maps are on screen.^[1]
• hud_batching submits fewer draw calls for the HUD. If HUD elements look wrong, try turning this one off.^[1]
• fast_text_lookup caches some data between text characters, which slightly speeds up rendering large amounts of text.^[1]

Unverified This pack doesn't ship a config file for ImmediatelyFast, so it's unconfirmed which of these options are enabled by default in this version or whether the pack changes any of them.

Same as in the All the Mods 10 2.11 guide

There's nothing to tune here. The pack ships no config file for this mod, so it runs entirely on its own defaults and there are no pack-changed values to point out.^[1]

That's fine, because the mod is built to be a drop-in client-side speedup. It replaces the immediate mode rendering path with a custom buffer implementation that batches draw calls and uploads data to the GPU more efficiently, covering entities, block entities, particles, text, the GUI and HUD, and immediate mode rendering from other mods. It also swaps in faster implementations for map rendering, HUD rendering and text rendering.^[1]

Unverified The mod may still generate its own config file on first launch outside the pack's config set, but nothing in the pack's files confirms that or any option names, so treat any settings you find in-game as unverified for this pack.

All the Mons 1.3.0 ships ImmediatelyFast 1.6.13+1.21.1 for NeoForge. The mod has been in the pack since 0.3.0-beta or earlier. The pack changelogs have no entries for this mod, so the history below comes from the mod's own changelogs for the latest releases.^[2]

1.6.13 (the version in this pack)

• The depth test state is now restored after flushing the DrawContext. This fixes a graphical issue with the Map Atlases mod.^[3]
• Fixed an exception when closing unused buffers. The changelog notes this fixes a crash in the ATM10 modpack.^[3]
• Fixed a config file handle leak.^[3]

1.6.11

• Fixed the render order of the villager profession level layer.^[4]

1.6.10

• Fixed Iris shadow pass outline buffer clearing, which fixes memory leaks with mods that render into the wrong buffer.^[5]
• Fixed the render order of the villager type and profession layers.^[5]
• Fixed a logic bug in the core shader incompatibility detection.^[5]
• Added an advanced memory leak detector.^[5]

1.6.9

• Made the mod compatible with Java 25.^[6]
• The Iris shadow pass outline buffer is now cleared in case mods render into the wrong buffer. This fixes a crash with glowing entities rendered with geckolib.^[6]

If you're updating the pack from an older release, these are the fixes you pick up with 1.6.13. They are mostly crash and rendering fixes, plus the new leak detector from 1.6.10.^{[2][3][4][5][6]}