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awakeningfromobliv
10-20-2007, 01:35 PM
Can UE3 do dynamic ambient occlusion?

http://www3.incrysis.com/images/crysis_pom_chicken1.jpg
Parallax occlusion

http://www.incrysis.net/screenshots/crysis_ambient_occlusion.gif
Dynamic ambient occlusion

http://www.cgarchitect.com/news/Reviews/VUE5/pic_05.jpg
Global illumination

karmatized
10-20-2007, 04:17 PM
the first 2 maby, but the 3rd global illumination i dont think so. your talking about photon processing i dont think you will see any game anytime soon do that.

as it stands no game comes close to real time raytracing

Oblivionbringa
10-20-2007, 05:10 PM
No to all 3

Technically however you could write a parralax occlusion shader for it if you wanted.

Currenlty ue3 can only do your standard parralax material. ( Epic refer's to it as bump offset material )

Also you could precompute ambient occlusion in 3ds max, and apply the ao maps to your models using the material system. Dynamic ambient occlusion is something I would imagine to be very slow, although perhaps they can do it easily with DX 10, I am not sure.

As for global illumination. The main reason most game engines do not support this for their precomputed lighting is a matter of speed and practicality. It can simply make lighting build times insanely huge.

eckz
10-21-2007, 06:25 AM
is that parallax occlussion mapping similar to fear's when you shoot hole in the wall etc? that kind of looks ok, but that stone ground thing crysis is doing looks 10000x times sweeter..

ION3
10-21-2007, 08:58 AM
This company is part of epics IPP (http://www.beyondunreal.com/content/articles/169_1.php/)

Geomerics (http://www.geomerics.com/products.htm)

awakeningfromobliv
10-21-2007, 10:58 AM
Wow that kinda Sucks. oh well.
Thanks

RealmRPGer
10-21-2007, 05:58 PM
Somebody got their facts messed up. Parallax occlusion mapping is sortof in. It uses a method called displacement mapping.

I believe UE3 had built-in support for ambient occlusion, but enlighten enables both (sort of).

From the UnrealWiki:

# Spherical harmonic lighting
* Real-time spherical harmonic maps for all lighting types
# Real-time ambient lighting
* Real-time ambient maps for all lighting types
# Radiosity lighting
* Fully real-time PRT (Precomputed Radiance Transfer) radiosity pipeline support This is a form of ambient occlusion
# Global illumination
* Fully real-time true beam tracing global illumination for dynamic lights
* Included Geomerics's Enlighten (Unreal Engine 3 IPP)

Parallax mapping As far as I know, this isn't actually parallax occlusion, but the engine has many other methods:
* Steep parallax mapping
* Bump offset mapping

# * Offset mapping
o Per-pixel displacement mapping with distance function
o Parallax mapping with offset limiting
o Relief mapping
* Relief texture mapping
o View dependent displacement mapping
o Relief texture method
o Virtual displacement mapping
* With self-shadowing
* With z-bias correction

# 'Real' displacement mapping (a.k.a. vertex textures fetch or dynamic vertex texturing)

* With LOD based tesseration and deformation
* With real-time lighting
* Displacement mapped water effects
* Displacement mapped snowy effects

Dead Ghost
10-21-2007, 10:01 PM
The first of the two are included in Crysis game, DX10 only. ;)

Oblivionbringa
10-21-2007, 10:32 PM
I have looked through that wiki article and found it to be riddled with inaccuracies and falsities. I also find it to be misleading at the lack of distinguishment between IPP tech and the out of the box ue3 tech.

Anyways bottom line is, yes ue3 has the framework to support parralax occlusion, but you will have to write the shader/material for it.

Also note that the shader in crysis is a self occluding and self shadowing parralax effect. I dont think it is possible to have a self shadowing shader like that in dx 9.

Out of the box, ue3 does not support dynamic ambient occlusion, global illumination, and PRT. Only if you are a developer who has licensed and integrated the Enlighten middleware would you have such features. To date however I am not aware of any developer using Enlighten.