Convert skydrome to skybox?

How can I convert a skydrome to skybox?

Thanks

You may take a look at HDRShop. (Version 1 is free to download)

http://www.hdrshop.com/

It can transform environment maps into different formats. (Panoramic Transformation)

However, you'll only get a 'vertical cross'. (6 sides in 1 image). You have to make each side a seperate image/file. Strangly Unity demands 6 seperate files to generate a cubemap. This is kinda retro.

You might also check Nvidia or ATI for developer tools.

http://developer.amd.com/gpu/cubemapgen/Pages/default.aspx