While using MultiMC to load IC2 Classic I found that it crashed on launch. I tried disabling IC2 Classic (preventing forge from loading it) and then it worked. I re-enabled IC2 classic and disabled all my other mods. Again, it worked. I then started enabling mods one by one until it stopped working. When I got to OptiFine, it started crashing again. To be sure it was the culprit, I disabled all the other mods so I only had IC2 classic and OptiFine and it kept crashing. The specific versions I am using are:

Operating system: Ubuntu 22.04 LTS
Java: openjdk 17.0.5 2022-10-18
Minecraft: 1.19.2
Forge: 43.1.1
IC2 Classic: IC2Classic-1.19.2-2.0.1.jar
OptiFine: OptiFine_1.19.2_HD_U_H9.jar

Crash report here: crash.txt

I use a lot of resources to make minecraft look nicer (for example, flash animation) and almost all of these resource packs use the optifine function to work properly. There are no alternatives in this case for forge. What can be done in this case?

@HeroxeT yeah then you are out of luck.

@JasonS05 sorry but there is 0 optifine support from me.
For all its worth the dev can fix it himself or it will never be fixed.

I actually tried working with him once and found a bug in his code with chunk pregen.
Where he didn't do certain checks.

And yes he fixed that rather quick, but i kept getting bugreports about the same crash.
Now i was lazy, but after almost 1 year of constant reports i found out he never offically released the patch he made.
Not only that he skipped releases with a CRASH FIXING BUG.
I had to hound him for long, Community backlashing and him being a dick,
So yeah after that I said 0 Optifine support. Even if i am the cause.

I won't go out of my way to break optifine support, but i won't check if it works.

So yeah @sp614x FUCK YOU!

@JasonS05 Use Radium/Rubidium instead, they provide a lot more performance in comparason and I support these two mods actually.

Optifine is the worst you can go by and there is better alternatives for everything it provides.

For everyone reading this later. If you want to replace Optifine with alternatives
here is your perfect reddit thread listing everything.
https://www.reddit.com/r/feedthebeast/comments/wyyymx/stop_using_optifine_goddamit

Pinning this so people can see that I don't care if optifine works with it or not.

@Speiger thanks for letting me know you won't support OptiFine (and why). I'll look into Rubidium/Radium then.

@JasonS05 sorry. Touchy subject...
No attacks go to you only to you know who.
If you felt attacked i am sorry that wasn't my intention.

@Speiger no I didn't feel attacked or otherwise insulted. Sometimes it's a bit hard to convey subtle feeling over text (lack of intonation and such) so I understand why you might've thought I was unhappy. Now that I read my comment again I realize the first sentence comes across as sarcastic, but I didn't mean it that way.

@JasonS05 no worry, i just wanted to make sure 💯

@snowstarlfy there are other alternatives out there.

So, if you dont support OptiFine, how can i play ic2c with shaders?

@HeroxeT Use Entity Model Features + Entity Texture Features.