serpantino: I don't think you understand. Paper Mario did use 3D for the backgrounds etc which lent to the depth and even though there were 2D elements they were mounted onto a flat 3D element.... whereas Rayman Origins is entirely drawn in 2D & doesn't use a 3D engine at all (So no polygons) think of it as a HD Snes/Megadrive game. To make it 3D they would have to attach every art piece in the game to a 3D model of a varying depth... it'd be very time consuming.
Edit: Infact Paper Mario seems to use Cel Shading.
Tizzysawr's post that directly follows the one of yours I'm quoting is right. You don't need a 3D engine to do 3D, you can just give different elements different amounts of left/right offset between the 'left and right halves' of the screen. To make something appear further away, you just need to have it a bit to the left on the left eye part of the screen and a bit to the right on the right. Same place on both = level with the screen.
There's a 3DSware game called Mutant Mudds which actually uses this to great effect.
Fever_Discordia: That sounds like what we, back in the day, called 'parallax scrolling' as seen in Shadow of the Beast on the Amiga and, of course, Parallax on the C6m only done on actual 3D hardware!
Sort of, yeah! In this case though, you offset the distant layers so that they actually appear further away. It's actually really effective when done well.
