To get fullbright in Minecraft 1.12.2 without using OptiFine, you can use specialized resource packs that adjust light levels or manually edit your game's configuration files to "over-brighten" the lighting. 1. Recommended Resource Packs (No OptiFine Required)
If you are running a modded 1.12.2 instance (like RLCraft), you can use a dedicated mod rather than a resource pack. Full Brightness Toggle (Modrinth) fullbright texture pack 1.12.2 no optifine
Simple Fullbright: This is a popular choice that works across nearly every version of the game, including 1.12.2. It doesn't change textures; it only removes darkness in the Overworld, Nether, and End. To get fullbright in Minecraft 1
Maybe you play on a lightweight client, you’re using a mod that conflicts with OptiFine (like certain shader cores or Forge compatibility layers), or you simply want a zero-performance-impact solution. Enter the Fullbright Texture Pack. Full Brightness Toggle (Modrinth) Simple Fullbright : This