cmftStudio

With this tool you can create cubemaps from HDRIs and export the faces as separate textures. It also allows creating of irradiance maps.

Install

• get it here

Usage

To store the the faces as separate files:

• File type: '.tga'
• Output type: 'Facelist'

Then load the faces in to Gimp, export them with the RAWTex plugin and convert them to a .tex with the command line texturetool. Also keep in mind naming convention for the cubemap faces.