Info about the UV/Texture Coord export feature?

[GregFinger]

I'm guessing this feature could be very useful when not using Omnidome in a live setting. For instance, I can use my Macbook Pro just for mapping out a dome and solving the necessary blending. Then for show time, I can use these exported textures on my Windows workhorse machine, which can handle realtime video processing and effects a lot better than my Macbook, to warp each projectors image.

I notice that when you export a "Plain Image" each projector gets it's own texture, and each Texture is split into two parts. I'm guessing the top part is for the blending, and the bottom part is for the pixel displacement. The top part is a little more straightforward, however it seems a bit more complicated than just your normal gradient blend mask.

The bottom half I can't really interpret.

However, the biggest confusion for me is how to use this texture in a live setting. With pixel remapping/displacing methods I've used before, usually the texture references a certain part of the main image. Since the main image is fairly large (and most likely a square resolution in a dome's case), but the texture is smaller and rectangular (to match the projector), the texture would indicate which part of the main image to take the pixels from and how to warp/blend them. Is this also the intended function of the export feature?