Hi,
It was actually a panorama taken from a photograph (Static), it's not 3k x 1k, I think i was higher than that :P and worldviz automatically resized it to nearest power of two. Now, instead of using a sphere I used the environment mapping in vizard, so I generated 6 images of 2k x 2k for the skybox. the graphics card is geforce quadro (i'm not sure which series), and it has only 128 mb ram. then again... displaying 6 images of 2k x 2k seem to have better performance compared to a > 3k x 1k on a shpere... I could be mistaken, since you mentioned about the "compression" I might see how this might work with .dds format with mipmap enabled.
This is not a part of any project, only something which I do in my own spare time to push how far can the PCs go.
My avg frame rates for most scenes with 6 images (2k x 2k) would be 25 - 50 fps, no higher than 50 with terrain. with no terrain, only hires (2k) skybox can go up to 70 fps, with 1k skybox and no terrain I can hit up to 100 fps
thank you for your inputs, this technique would definitely improve frame rates.
Regards,
-e1-