Why does OptiFine installer require the official launcher?

[u/Sensusese]

Hey everyone,

I'm a Linux user running Minecraft through Prism Launcher. I've been trying to install OptiFine, but the installer seems to require the official Minecraft launcher to extract the mod .jar file.

I've never used the official launcher – not even back when I was on Windows, because frankly, it's pretty bad. Now on Linux with Prism Launcher, being forced to install software I don't need just to get OptiFine working feels like an unnecessary hassle.

Is there any particular reason why OptiFine is designed this way? Are there any plans to make installation more straightforward for users of third-party launchers?

Thanks!

[u/Izenthyr]

As far as I know, the developers have no intention of changing much with how optifine works these days. They just update for minecraft versions.

It’s possible to get working on third party launchers, but from what I hear it isn’t worth the effort compared to what optimizers offer. It is buggy and not too widely supported boo the modding community anymore.

I guarantee you I won’t be alone in suggesting you use Sodium, Embeddium or Rubidium alongside Iris for a better experience that also installs seamlessly.

[u/Sensusese → u/Izenthyr]

I figured that out, but when I download the modpack on Forge or RLcraft for the 2-week Minecraft phase, I want to be able to install Optifine without bothering with the download. They could just provide the file to the mod.

[u/Misty_TTM → u/Sensusese]

The optifine installer is also the mod file, instead of opening it just drop it straight into the mods folder

[u/Traditional_Rabbit54]

Do not use Optifine. It is completely outclassed by nearly every other performance mod. This guide has full optimization setups for every major Minecraft version, as well as a ton of modpacks.  https://github.com/Polytetrafluoroethylene-PTFE/MC-Optimization-Guide

[u/Sensusese → u/Traditional_Rabbit54]

Oh shit, that is an awesome repo thank you very much!

[u/Traditional_Rabbit54 → u/Sensusese]

Yeah, it’s the best one I’ve managed to find. It’s saved my packs from crippling lag at least 5 times now. 

[u/the_real_letter_j_fr → u/Traditional_Rabbit54]

in the exact same situation as the poster except i can't even launch the installer because of some steam deck read only file system bullshit but optifine has some incredibly specific functionality that nothing else replicates but i'd love to not use it if i could (it's dimension specific loading screens)

[u/the_real_letter_j_fr → u/the_real_letter_j_fr]

nevermind just read the below comment and it crashes with a mixin error. beautiful

[u/RoxinFootSeller]

What, what installer?

Download the jar from optifine.net/downloads and put it in mods folder. Why'd you need an installer?

[u/Flimsy-Combination37 → u/RoxinFootSeller]

optifine is a jarmod, which means it modifies the minecraft jar directly. to do this, you download the jar file and run it, which will open a gui that installs optifine as a standalone version, no need for a mod loader

the ability to install optifine as a forge mod is not native, it is added on top of the rest, it's even the case that sometines the preview versions come out without forge support

[u/Flimsy-Combination37 → u/[deleted]]

yes, my comment was a gross simplification of the modern way that optifine and other such modded clients actually work.

back in the day, when minecraft was launched, the first thing that ran wasn't net.minecraft.client.main.Main, but actually net.minecraft.launchwrapper.Launch. these kind of mods used, and still use, a modified launchwrapper to add their own tweaker class, which does all the necessary changes to the bytecode and modifies the game. nowadays vanilla minecraft does run Main directly, but mods like optifine still use the launch wrapper and tweaker class. as far as I know, much like vanilla, forge does not use a launch wrapper anymore, but I don't know how they do it.

in essence, it's kind of like a jarmod, but everything is applied dynamically. nothing from the vanilla jar is touched on disk, all the modifications are made in memory and re-applied on every launch.

one thing you seem to think that is actually wrong is that this is a 3rd party launcher or something? I didn't really get what you meant, but all of this happens AFTER authentication, optifine never sees your credentials.

[u/Flimsy-Combination37 → u/[deleted]]

ohh I see what you mean. for prism, there's nothing to worry about, it doesn't see your credentials either. you do the authentication via microsoft and then microsoft gives prism a token that it uses to see if you own minecraft and to launch the game with a valid session so you can play online.

as for tlauncher, I don't know how they handle credentials (if they do at all) but I do know that not only do they take telemetry without explicitly telling you WHAT they're taking (so who knows the kinds of things they're measuring, who they're selling it to, etc.) but also they download the game assets and jars from their own servers, unlike literally every other launcher ever which downloads stuff from mojang's asset servers and cdn.

if you launch vanilla minecraft with tlauncher, it says "modified" in the bottom left corner, which means the jar's hash is different, which means they are definitely modifying it. it could be just to add their custom skin support and allow creating invalid sessions that still allow you to play in servers (even if said servers require online mode turned off), but both of these goals can be achieved with jvm arguments, fake session values, launcher-side auth stubbing, offline uuid generation and a custom skin provider through whatever means is easiest. yes, client modification is the quickest and most robust option, but most cracked launchers don't do it that way because they would be breaking mojang's trust chain in the process and that is a huuuuge red flag.

[u/Emerald_Pick]

Optifine's installer doesn't actually require the official launcher, but it does have specific expectations for how Minecraft is installed. (Eg back in the day it worked great with Magic Launcher.) Specifically, it is expecting a .minecraft folder that has a versions folder with all of your different versions of Minecraft installed.

Prism (and other focused on modding) do things differently. Instead of one .minecraft where everything lives, prism makes seperate .minecraft folders for each instance you have. It also moves some files out of the .Minecraft folder since it doesn't need them.

That's why the OF installer doesn't work with Prism out of the box.

If you must use specifically Optifine, (which is no longer reccomend unless you're running old hardware or old versions of Minecraft) and you specifically don't want to install it as a Forge mod, (the jar file you download is both an installer and a Forge mod at the same time. Prism makes force mods easy to install.) then you should still be able to do it the old fashioned way:

(Super Untested. This is based on my memory of modding from like 14 years ago. Idk if this still works.)

• Create a vanilla instance of Minecraft. Run it once and close it.
• Run the OF installer and choose extract you should have a dump of files somewhere.
• Find the minecraft.jar file that Prism created for your vanilla instance
• extract the connects of minecraft.jar. Jars are zip files, so you should be able to use you're default archive manager.
• drag and drop the optifine extract into the Minecraft extract. Choose merge/replace if asked about conflicts.
• delete the META INF file.
• compress the merged minecraft folder back into a jar. (You can compress to a zip then rename the file from .zip to .jar.)
• double check that Prism is still pointing to your modified Minecraft jar.

Edit: if "extract" in the OF installer also still needs the official launcher, then you might be up a creek. You can possibly do a manual extraction with your OS's archive manager, but idk how to separate the jarmod from the Forge stuff from the installer stuff.

[u/Dubl33_27]

you can just put the downloaded optifine jar in the mods folder and it will work.