Fullbright Texture Pack 1.12.2 No Optifine [best] -
If a texture pack doesn't provide enough light, you can manually force Fullbright in 1.12.2 by editing your game files: How to Get Fullbright Texture Pack for 1.21.11
This method works because Minecraft reads a file called lightmap.png to determine how bright each light level should appear. By replacing this file with a fully bright white texture, the game renders all blocks at maximum brightness. fullbright texture pack 1.12.2 no optifine
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