Texture pre-processing tool for expanding texels into unused areas, to avoid filtering artifacts.
C C++ Makefile QMake
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texpand is a texture pre-processing tool, meant to be used as part of the content pipeline for games, or other graphics programs. Its main purpose is to expand texels to cover all adjacent unused areas in the image, in order to avoid filtering artifacts during rendering.


Additionally, texpand is also able to produce texture coverage images, visualizing the unwrapped 3D models in texture space, which can be used as input for the expand operation, or used as reference for artists to paint the texture of an unwrapped model.

Finally, texpand may also be used to calculate the percentage of used space in a texture image, which can be useful to issue automated warnings during asset builds, for inefficient use of texture storage.

In addition to the command-line program, which is suitable for inclusion in content pipelines, there is also a GUI version, imaginatively called texpand-gui, which might be handy for interactive use and experimentation.

gui shot


Copyright (C) 2016 John Tsiombikas nuclear@member.fsf.org

This program is free software. You may use, modify, and/or redistribute it, under the terms of the GNU General Public License version 3, or at your option any later version published by the Free Software Foundation. See COPYING for details.

Build instructions (texpand)

texpand depends on the following libraries, which need to be installed system-wide before building:

Simply type make to build, and optionally make install to install texpand. If you don't want to install to the default prefix (which is /usr/local), make sure to modify the first line of the Makefile.

Build instructions (texpand-gui)

In addition to the above, texpand-gui also requires Qt 5.x to be installed before building.

Change into the gui subdirectory of the project, and type qmake && make. Install as usual, by running make install.


Usage: ./texpand [options] <texture file>
   -o <fname>: output filename
   -uvset <n>: which UV set to use for mask generation (default: 0)
   -radius <n>: maximum expansion radius in pixels
   -force, -f: use all meshes in mask gen. without matching the texture filename
   -genmask: output the texture usage mask
   -mesh <fname>: use mesh/scene file for generating the texture usage mask
   -mask <fname>: use a mask file instead of generating it from geometry mesh
   -maskalpha: use alpha channel as the usage mask
   -usage, -u: calculate and print texture space utilization [0, 1]
   -help, -h: print usage information and exit
 (exactly one of -mesh, -mask, or -maskalpha must be specified).


Currently texpand uses X11/GLX, to create an OpenGL context for building the mesh coverage mask. So it needs a running X server supporting the GLX extension to work. The connection is only attempted when building a mask however, so it doesn't affect the other modes of operation.

Meshes with texture coordinates beyond the interval [0, 1] are clipped.