3D in Crysis 2 demo not actually 3D

Crytek says that the 3D mode in the Xbox 360 multiplayer demo of Crysis 2 does not represent the quality of the stereoscopic support in the final game.

Analysis of the Xbox 360 multiplayer demo suggests that Crysis 2's 3D mode is an optical illusion based on stacked 2D layers - a sort of basic diorama effect as opposed to creating individual views for each eye.

It's an interesting trick that does indeed generate an impression of depth as discussed in the Crysis 2 Demo tech analysis, but it's clear now why we thought that the 3D effect is so easy on the eyes... It's because there is no actual 3D as such in the demo code.

From what we can gather, the "3D mode" takes certain elements of the image and then shifts them horizontally a set number number of pixels, with that value adjusted according to the 3D strength selected in the options.

Three distinct layers are processed: the HUD, the view weapon and everything else - which is basically the entire scene. When beamed to a 3DTV, this gives the impression of the HUD being close, the gun being further away, while the main environment is recessed further back still to give an impression of 3D.

So what happens when you cancel out the pixel offset? We've done just that in this video, confirming that the view per eye is identical.

We asked Crytek to clarify the situation, as the firm's own GDC presentations suggest a "2D plus depth" approach is used by CryEngine 3 on console, similar to the TriOviz tech, recently integrated into Unreal Engine 3.

"You're actually right, the demo still uses an outdated stereo implementation which has very little depth," Crytek's Jens Schaefer told us.

"The final game has a lot more depth and a lot of progress happened. The 360 demo did not integrate the updates and thus 360 demo is not representative regarding S3D."

While the implementation as it stands in the Crysis 2 demo isn't all we expected, the technique itself is intriguing and for games where significant amounts of the gameplay area are created from a series of flat layers (such as LittleBigPlanet), it may have some value.

In the meantime, Xbox 360 players might like to revisit the multiplayer demo - the Pier 17 "secret level" now appears to have been completely unlocked, and it's well worth checking out.