343 sometimes had to do more than just tweak Halo: Anniversary's visuals

343 Industries's Frank O'Connor has said the team did a bit of tweaking tot he visuals in Halo: Anniversary, and not just when it came to enhancements.

Speaking with Gamasutra, O'Connor said in some areas of the game, previous visual effects were also removed.

"For example, 343 Guilty Spark had a lot of fog, and people associate that fog with broodiness, mood, terror as the Flood came out," he said. "But one of the realities is that yes, the fog was there for all those reasons, but it was also in there as a performance saver, as fog used to be. [So we found] other things we could do to give it mood and give it a somberness.

"We also said at some point, 'If we're doing something with the graphics, we should really do something with it, not just ape exactly what was there. The Library is another good example.

"It had this big pillar in the center which was put in, again, to occlude objects so you don't have to draw every enemy in the game. We took this opportunity to re-light the level, do stuff with the textures, and some of the effects to make it much more navigable."

Halo: Combat Evolved Anniversary is out November 15 and will contain support for 3D tvs.