What's the main menu background screen in Minecraft 1.8 based off?

I'm referring to the blurry scenery in the background.

Is it just randomly generated? Is it sometimes based off worlds you've made? Or is it neither?

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2 Answers

It is a mesh of 6 PNG files displayed sequentially (and with a wonderful transition!). These files are located inside your minecraft.jar inside title/bg (So yes, you can change them).

Source: I found them while browsing the jar, then stared at the background to confirm that they matched.

Also, the 2 computers I tested had the same files, so it stands to reason that minecraft.jar does not dynamically generate them.

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As john said it's located in the minecraft.jar file inside title/bg. Here's a little video on how to change it :D

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