Theme files are the interface customization standard for Uxn software.

A .theme file contains 6 bytes equal to 4 colors, divided into 3 shorts corresponding to the RGB channels.

0a6f 05cf 0caf

The previous theme data corresponds to the following 4 colors:

Uxn Routine

A simple routine to load a local theme file in Uxn is as simple as:

( theme )

@theme-txt ".theme $1

@load-theme ( -- )

	;theme-txt .File/name DEO2 
	#0006 .File/length DEO2 
	#fffa .File/load DEO2

	.File/success DEI2 #0006 !! ,&ignore JCN
		#fffa LDA2 .System/r DEO2
		#fffc LDA2 .System/g DEO2
		#fffe LDA2 .System/b DEO2
		&ignore
	;redraw JSR2

RTN

Applications supporting the format include Orca, Left, Nasu, and Noodle. Nasu is able to export a .theme file with ctrl+p.