Exactly. First I didn't understand why MegaTexture was implemented in a production-ready game (Rage) because it made lots of texture look like a decade old, but I guess Carmack sees the future in it.
Rage was a huge shame (tech wise). They needed to be able to ship more data to make the tech really shine. The game was 3 DVDs as it was but it needed to something more like 8 or 9 DVDs.
It just feels like such a shame for the graphics to look bad for want of the ability to ship data to the customer.
Hm. I only played the PS3 version, but was actually impressed by the graphics. Not only does it look great, it runs smooth as butter, especially when moving. I don't think the Rage engine was ever built for still shots, but in movement, it think it is gorgeous.
I don't know how they did texture compression for Rage, but the pc version was 24gb. Skyrim came out a month later and was 7gb. They had "some" reasonable texture quality on character meshes and such, but a lot of the world textures were pixelated garbage - I have no idea where they had the game become so bloated it was 24gb like that.
Reminds me of the Force Unleashed, which was another game that took up 25gb for no reason whatsoever, when the texture quality and game size were no larger than War for Cybertron that took up 8gb.
It has to be their texture compression in use, but they should figure that out early on! (note, I have no idea what I am talking about).
Rage uses a new rendering approach in which every surface has a unique texture. In a normal game, textures are reused all over the place. The texture compression Rage uses is actually very good, it's just that the data set is massive.
Their raw data set is much, much larger than what they shipped. Carmack has given out figures like 300gb per level.
In order to cull that down to a game that can fit in 24gb, they had to drop a huge amount of detail. The way they did it was quite interesting as well.
They get telemetry on clients playing the game, and then they build a weighted set of textures at each mip that were actually loaded by real clients. Then they take the highest weighted 24GB of them, and that is what they ship.
Why are you so opposed to this idea? I think it would work well if implemented properly. It's similar to how games like GTA IV work. They don't load a level, they load the immediate area you're looking at. As you drive around, the new maps are streamed from the DVD. Other games have played with loading a small first level, and as you're working through the first level the rest of the game streams into cache behind the scenes.
It would be nice to get a game on a 4GB DVD and have the rest of the data get pulled down as you're playing. Guild Wars did this. While you're in one zone, the next zone is being downloaded in the background. It would only work for geographical regions which don't have caps on Internet traffic (for example, Americans on Comcast, but not Canadians on Rogers), but it'd be a nice option.
I haven't looked into MegaTexture much, but from what I can tell it doesn't repeat terrain textures.
In most modern games, smaller textures are tiled over larger areas, allowing for lots of detail for less memory at the expense of variation. Most do something to mix it up (mixtures of textures, adding random variations), but it ultimately constrains what can be done.
MegaTexture seems to solve the problem of using a single large texture by streaming only the parts needed, but requires much more data on the disk to match the detail level of tiling.
You can't really compare it to skyrim though. Skyrim doesn't use mega texturing (or virtual texturing). It repeats textures all over the place.
In rage, there is a huge texture for everything.
IIRC, the uncompressed textures performed a total of 1.5TB or something like that, so I would say that they did an awesome job with the compression.
