I thought cubemaps were a 360 degree view of your entire surroundings mapped onto the faces of a cube as though you were inside the cube. And then unwrapped into a 2d bitmap, of course.
No grass or trees, I'm afraid.
, and yes that was done quite some time ago in 980. This is one of the panels at full resolution:
I used Corel PhotoPaint to put them together and manually blended them.
I did find a free program called Image Composite Editor (ICE) that is made to stitch together frames of a panorama, didn't work too bad, but I had better results doing it manually.
I did try doing a few videos, but never had any luck with them. Perhaps I should try and start with smaller resolution videos first. Don't remember the software I used, but I don't think the final file size was terribly small neither, I think that's why I quit trying.
But speaking of videos, I spent quite a bit of time on HapNStance's youtube chanel. He puts together some nice videos.