Game Informer Halo Reach information.

[JaggedSac]

* "We basically hit every single piece of the engine, making things better across the board"
* New tech engine starts with a refined approach to distance and detail that allows for a dramatically expanded number of enemies, light sources and other details.
* The engine is an "imposter" engine using a smart, yet common programming technique for the engine and the new LOD system.
* There can be a large amount of "imposter" objects both far and close to the player. Far objects still look greatly detailed despite having low polygon counts and cheap shaders (at a distance). They look much more detailed the closer the object is to you. "Imposter" objects that are really close to you are SUPER detailed with much clarity.
* Adding all these objects (vehicles, enemies, buildings, scenery, etc.) don't take a profound hit to the system because of the technique they're using.
* The imposter system frees up memory that Bungie can use for other in-game enhancements, the first of which is lighting.
* Halo: Reach can have 20-40 dynamic light sources at one time, the most notable of which are on weapon effects.
* "As plasma bolts come searing past, they move across the screen with each plasma bolt having its own independent light source, casting color and shadow about the space to remarkable effect."
* Refined approach to distance and detail
* Allows dramatically expanded number of enemies, light sources and other details
* Described as "imposter tech"
* Level of Detail (LOD) system allows building of bigger and more populated spaces for exploration
* Distant objects are rendered at low poly with cheaper shaders, ie "imposters"
* Imposter look great at distance and detail increases the closer you get to them
* Less chance of pop-up and stippling as environmental geometry, plants, buildings, enemies or anything else can be placed into the visual field at the same extreme distances without profound hit to system performance
* At extreme close range items can be rendered with incredible detail, ie, a wall was shown from inches away with tiny rivet features in the metal popped on the screen with perfect clarity
* Imposter system indirectly frees up memory which can be devoted to other technical aspects
* Lighting being one of those aspects
* From Halo 3's 3 or 4 light sources, Reach's engine presents 20 to 40 dynamic lights at the same time
* Weapon effects benefit greatly from the improved lighting, ie Plasma bolts moving across the screen with their own independent light source, casting colour and shadow across the environment
* More improved lighting examples, a Warthog gun firing at a wall with hundred of real sparks flying from the stone, the particles interact not just with the wall geometry, but with it's normal map additionally, the particles scatter down onto a nearby vehicle and react with its curves and lines, the sparks bounce and flow along the tiny textured surface
* New weather system bringing rain to many missions, adding to the atmosphere
* The sky is no longer a sky-box like past Halo games, it's a true space in the overall environment, ie a ship descends from orbit and towards you, you can watch it make the full descent as a real object would fall
* Motion capture heavily implemented, a majority of the cut-scenes based on captured actions
* On-screen characters exhibit an animation technique known as variable gait blending, when a character changes speed, ie walking to running and vice versa, the animation of walking blends seamlessly into running and then sprinting, also, when turning on a pivot, players no longer stay still and magically turn in a circle, they realistically move around the pivot with their bodies and lifting their feet in reaction
* Bungie hired company Image Metrics to aid with human faces, which now appear dramatically more lifelike than Halo's traditional potato faces