Okay, but let's not be so flippant that The Medium is "
just split screen", as if split-screen and full-scene replacement and
anything like this is "easy"...
What R&C Rift Apart is doing could not have been done before because entirely new level data just could never load in that fast, but I actually could think of cases where The Medium's approach would be beneficial still to the developers. Like in this case above, the way the do that full-screen effect I believe is they have two concurrent versions of the game running simultaneously, one in the real world and one in the horror world, and you would even have two characters walking the path at the same time synced to the controller. Limits are severe, because you can only stress the memory and processor just half as much as a regular game (or less, realistically) in order to have both areas running in parallel to switch back to. So, that's bad. However, do it and the work (and sacrifice) is already done. The action is already synched, the two halves of the levels are built, and you found a way to squeeze it all in. So now, you can just go wild. The character is already on the road in both cases, running at the same speed as you hold the controller, and so the developer can flash back and forth whenever they want because the two sequences are perfectly aligned. Just put little flashes of color or smear to hide the transition and you flip between them in an instance. So long as there's a limiter to not let you flash when you're walking over a cliff or an enemy is in the way (which you can know because, again, the other world you're about to flash to does indeed exist and they can check that before it makes the flash happen,) you can mess with this sequence as much as you want.
Compare that to the Rivet sequence we see in this video. Rivet comes up on the rift crystal, hits it, and the whole game pauses. It's just the briefest of seconds, but the whole game has to stop because, well, there kind of is
no game to play in between the moment where the one level goes away and the new level appears.
Or you can do the other thing Rift Apart does where Ratchet falls into a purple void of levels, where he flips up in the air and cartwheels through a big open void of rift shards until one pops up. Again, there is no game to play there because the level data has been thrown out and the game is streaming a new level in as fast as possible, so in the meantime, you get almost a "loading screen" of the rift shards. Unlike The Medium, R&C Rift Apart is not playing two games at once, and so the game does not have the stage that Ratchet will end up on loaded up until he gets there; until he arrives, the wheels have to spin idly. It also has difficulty seamlessly stitching momentum and character placement and anticipation of action on the other side because it doesn't have that other level yet loaded and it may not know what you'll be playing on until you get there.
Rift Apart does seem to have a variety of ways of stitching levels together (not all Purple Rifts are equal,) and in sequences that they call Pocket Dimensions, the transitions are totally seamless ala the Portal games (which you can do if the rift-entry and rift-exit points are specifically matched up and timed right ahead of tiem,) so hopefully there's a lot of those because those are super cool to watch. However, it looks like there are just times in the game where it has to pause and wait, even if it is an extremely brief wait.
(BTW, the new footage is kind of weird, because even when Rivet pulls a Yellow Rift to the same area, it still pauses, I'm not sure if that's just a player convenience or what the case is?)
Now, with the R&C approach, it's just plain cooler. What wasn't there is now there, and detail is at full glory because you don't need to keep the level you just left. And also, some clever tricks could be used to use the bridge between worlds as a benefit even if there's a level-change pause. (Like imagine if
this whole pirate ship from the demo fell into a void in the middle of your battle, and when it lands, instead of the sea the ship and everybody aboard is
sliding down that ramp about to fly over a cliff, and suddenly you're caring less about fighting the pirates and more about getting off this thing before it flings into an abyss? Same pirate level, same ground that Ratchet was standing on the whole time, but the physics changes from flat ocean to falling danger and also the objective changes too, all the while the visuals and lighting change all around to convey the change of location to a very dangerous predicament.) You can do more with this approach, and it's great that we have a console that is capable of doing this. But, there are drawbacks to not doing it the old-fashioned way (I'm actually surprised that Ratchet uses no parallel world loads, because Insomniac is a company that always keeps a good trick handy even if it has an even better trick to play,) and it will probably take even more experimentation with fast-SSD rift loading like this to achieve the same kinds of transitions in a R&C sequel as you would in a Medium sequel.
