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Alright. So, I have super high res m_doom, m_skull1, and m_skull2 textures, and they're really big while in the menu. Is there a way I can make these smaller?

[wiki]TEXTURES[/wiki], [wiki]HIRESTEX[/wiki], or just good ol' resizing in a graphics program.

You can redefine a graphic in either of the lumps while still using the graphic in it. So yes, you can make resize stuff in 'em.

Zombieguy wrote:..... Is there a way I can make these smaller?

Smaller than what?
I assume that you want to achieve a scale to the image it is to replace.

Place the hires images with the same name as the lores images in between HI_START and HI_END markers.
That will scale the hires image automatically to the size of the lores image.

If that is not sufficient, then, as XutaWoo mentioned, use TEXTURES.

Thanks Kappes Buur. Works like a charm.