....s *Light Shafts* feature enable in April UDK?

[unreal_polyneutron]

Finding an information about this amazing feature I tried to find it in A[ril build of UDK....but I don't find any *Light Shafts*-bookmark (or something like that)....

Source where i find information:
http://udn.epicgames.com/Three/Conte...ilt%20lighting

.....Any ideas? Or may be I miss something?....

[Hboybowen]

those another name for God Ray's which has been around for awhile

[eAlex79]

It probably will be in the *next* release, not in the April build.

[Phopojijo]

If you know exactly where it'll be -- it's typically easier (on the computer) to just have semi-translucent white (or off-white, or coloured if necessary) planes. I mean it's not *that* bad, but it's still cheaper to simply fake it... if you can.

Seriously, don't be afraid of plane/double-plane/box/etc. effects. They can be dang useful. Learn as much as you can.

[eAlex79]

http://udn.epicgames.com/Three/Volum...mTutorial.html

That's documented too

[Steve Polge]

Light shafts ("God rays") will be in the next UDK build. This is a new feature, different from the previous volumetric beam implementation.

[Dreamcube017]

Yeah but keep in mind performance issues. Some computers would much rather run the volumetric shapes than actually calculating it I'm sure.

HEY just had a hot idea.

What if there was some way to BAKE volumetric lighting in. So that the engine could calculate the shapes and things and then just generate meshes from those with the material to be used... kinda like lightmass does with GI and AO.

[Tom Shannon]

Ther performance hit is actually pretty small and certainly smaller than complex shaders applied to meshes all over your level.

This effect takes 1.9ms to render on Xbox 360. For reference, SSAO is ~2.5ms so this is actually cheaper.

(From the documentation)
You do however lose control over the light shafts. But it's also seemingly a LOT easier to set up looking at the interface.

[Xendance]

Would it be possible to use a location of a lensflare instead of the directional light direction as the source of the god rays?
Because lensflares are very good when used as fake sun, as can be seen on the GDC level. I'm just wondering because the directional light comes from infinite distance, while lensflares are in the actual world. So in extreme cases the lensflare could shift so that it wouldn't look like it's emitting the god rays.

[darthviper107]

It'd actually be nice if they could be used with spot lights as well, for localized effects

[Piranhi]

Would it be possible to use a location of a lensflare instead of the directional light direction as the source of the god rays?
Because lensflares are very good when used as fake sun, as can be seen on the GDC level. I'm just wondering because the directional light comes from infinite distance, while lensflares are in the actual world. So in extreme cases the lensflare could shift so that it wouldn't look like it's emitting the god rays.

I'm guessing it would be possible. As they are usable with a dominant directional light which is essentially an infinitely large light source coming from infinitely far away, they have no point so light shafts must have an option somewhere to set the origin. If it's as simple as the actual location of the DDL actor, then you can just put the lens flare actor on top of the DDL actor.

[darthviper107]

There's also the direction though. While technically there is a direction that the lens flare source actor is facing, you can't really tell except by checking the object rotation and try to figure it out from there

[KazeoHin]

Its theoretically possible for epic to implement Light-shafts for point-lights, however, Part of the effect is a whole-scene fog, and having a single point-light in a level create fog for the entire level is a bit unwieldy.

[Xendance]

I'm guessing it would be possible. As they are usable with a dominant directional light which is essentially an infinitely large light source coming from infinitely far away, they have no point so light shafts must have an option somewhere to set the origin. If it's as simple as the actual location of the DDL actor, then you can just put the lens flare actor on top of the DDL actor.

Hmm, you sure that the god rays use the DLL _actor_ location as the origin?
Because as far as I know the god ray source could also be infinitely far away, like the light source of a DLL o_O

[darthviper107]

Its theoretically possible for epic to implement Light-shafts for point-lights, however, Part of the effect is a whole-scene fog, and having a single point-light in a level create fog for the entire level is a bit unwieldy.

Not for a whole level, but lets say you wanted to have a light in a level have real-time volumetric lighting, like if I light was shining behind a slowly turning fan, it'd be a nice effect for the light shafts to be moving as well. Or you could use it for headlights on a car or a flashlight.