Perhaps the greatest sign of change is the inclusion of weather, something largely lacking from the original film. Yes, there were storm clouds near the castle, and the occasional fluffy in the sky, but no sign of actual weather conditions, really taxing the computational power.
Of course, back in 2001, Shrek was taxing enough for the poor mainframes, but in Shrek 2, we are introduced to sweeping deluges which pound spray in all directions, fragmenting visibility as the light diffuses through the rain, creating glowing halos around objects moving through it, and actually changing the way the ground reacts to passing vehicles.
On top of that, we get blizzards, show piled high, near-burying the characters, and again radically altering the landscape. Snow is not pure whiteness, it reflects, and changes the ambient lighting conditions. It is hard to gain traction on, and tends to scrunch away underfoot, moving and changing with each footprint, and tyre tread.
Let us not forget the fast-moving action pans, offering shaky glimpses from camera views of fleeing fugitives, racing through the underbrush, and half-concealing trees as the camera flails about, trying to get, and keep, a lock on the targets.
Rain changes everything
Shrek 2 is a masterpiece in many respects, not least for showcasing just how far things moved in just a few years ? going from close-in shots of great detail, to grand, sweeping visages with the same amount of detail. Just as funny as the original, and if anything, more realistic, Shrek 2 is a must for any shelf.
It truly advertises and advocates the type of virtual environment interactive virtual reality is striving for.