Gorgeous Unreal Engine 4 brings direct programming, indirect lighting • Hacker News Board

Re: Gorgeous Unreal Engine 4 brings direct programming, indirect lighting

#71

Post by pka » Sat, Jun 09, 2012, 5:50 AM UTC

The graphics stuff is amazing, but I'd be also interested to know how they achieve hot-loading with C++. It seems to me that Erlang's philosophy (or FP in general) would be of great advantage here - just have the engine handle entity state and make all of the game world manipulating functions referentially transparent. This way one can swap code between world "ticks" (or update cycles) without worrying about breaking something.

I don't know how efficient something like that would be though; somebody mentioned cache issues with lumping heterogenous properties together, but maybe this could be optimized behind the scenes.

Re: Gorgeous Unreal Engine 4 brings direct programming, indirect lighting

#72

Post by bvdbijl » Sat, Jun 09, 2012, 6:12 AM UTC

laserDinosaur wrote: post #21

The bit where he made a change to the source code, let it recompile on it's own, got a little alert in the editor when it finished and then had the change apply all without restarting the engine...WOW!

Just FYI, Eclipse for Java has the same feature http://wiki.eclipse.org/FAQ_What_is_hot_code_replace%3F

Re: Gorgeous Unreal Engine 4 brings direct programming, indirect lighting

#73

Post by SeoxyS » Sat, Jun 09, 2012, 7:06 AM UTC

dualogy wrote: post #46

dualogy wrote: post #39

Incredibly stunning tech. Now, I'm gonna go fantasize about an open-source version of this with updates every month (instead of every 3 years) -- as a compromise, I could do without the whole hot-reloading IntelliEditor shebang and consoles support -- a concentration on PC hardware that "will be commodity in 2 years, on mobile in 4 years, but can already be bought as state of the art now" (aka Kepler GPUs) would be e…

Also I'm wondering about the lighting. Some folks on Twitter called it dynamic Global Illumination but here they just call it indirect lighting. I wonder -- are they still using an ambient light? More specifically, what's their GI algorithm? Might be something like the voxel approach sported by @icare3D but then it seems that one's just barely interactive, not as "real-time" as this stuff -- or well it might be on a…

The physical renderer in Cinema 4D is pretty fantastic, and calls it Indirect Illumination. It's pretty crazy slow at rendering this stuff. I've had 6h+ renders, per frame.

Re: Gorgeous Unreal Engine 4 brings direct programming, indirect lighting

#74

Post by knghtwhosaysni » Sat, Jun 09, 2012, 9:31 AM UTC

dualogy wrote: post #46

dualogy wrote: post #39

Incredibly stunning tech. Now, I'm gonna go fantasize about an open-source version of this with updates every month (instead of every 3 years) -- as a compromise, I could do without the whole hot-reloading IntelliEditor shebang and consoles support -- a concentration on PC hardware that "will be commodity in 2 years, on mobile in 4 years, but can already be bought as state of the art now" (aka Kepler GPUs) would be e…

Also I'm wondering about the lighting. Some folks on Twitter called it dynamic Global Illumination but here they just call it indirect lighting. I wonder -- are they still using an ambient light? More specifically, what's their GI algorithm? Might be something like the voxel approach sported by @icare3D but then it seems that one's just barely interactive, not as "real-time" as this stuff -- or well it might be on a…

I'm not sure about UE4, but Geomeric's Enlighten tech was added to UE3 last year. It seems likely to me that it would be the same thing in 4.

Re: Gorgeous Unreal Engine 4 brings direct programming, indirect lighting

#75

Post by dualogy » Sat, Jun 09, 2012, 10:49 AM UTC

photon137 wrote: post #55

dualogy wrote: post #46

Earlier quoted context omitted.

Also I'm wondering about the lighting. Some folks on Twitter called it dynamic Global Illumination but here they just call it indirect lighting. I wonder -- are they still using an ambient light? More specifically, what's their GI algorithm? Might be something like the voxel approach sported by @icare3D but then it seems that one's just barely interactive, not as "real-time" as this stuff -- or well it might be on a…

Voxels would be too heavy. I have worked with volume rendering before and it's way too expensive to do it at this scale (although their scene with the light passing through the volumetric smoke column kind-of defied this). Some real-time version of PRT? "RTRT"?

Turns out it IS voxels! https://twitter.com/Icare3D/status/211404654062481408

(Of course the (fairly lo-res compared to your screen) voxelized geometry representation is not rendered directly to screen ala Atomontage or Gigavoxels -- the the GI is based on RT scene voxelization and approximate cone-tracing.)

Well that's awesome because at least there's (A) a paper for this (grokking it is another matter) and (B) seems like it runs really smoothly on next-gen GPUs!

Re: Gorgeous Unreal Engine 4 brings direct programming, indirect lighting

#76

Post by aw3c2 » Sat, Jun 09, 2012, 11:38 AM UTC

TwoBit wrote: post #37

laserDinosaur wrote: post #21

The bit where he made a change to the source code, let it recompile on it's own, got a little alert in the editor when it finished and then had the change apply all without restarting the engine...WOW!

FYI The Sims did that 10 years ago.

source, link, reference, anything?

Re: Gorgeous Unreal Engine 4 brings direct programming, indirect lighting

#77

Post by photon137 » Sat, Jun 09, 2012, 11:46 AM UTC

dualogy wrote: post #75

photon137 wrote: post #55

Earlier quoted context omitted.

Voxels would be too heavy. I have worked with volume rendering before and it's way too expensive to do it at this scale (although their scene with the light passing through the volumetric smoke column kind-of defied this). Some real-time version of PRT? "RTRT"?

Turns out it IS voxels! https://twitter.com/Icare3D/status/211404654062481408 (Of course the (fairly lo-res compared to your screen) voxelized geometry representation is not rendered directly to screen ala Atomontage or Gigavoxels -- the the GI is based on RT scene voxelization and approximate cone-tracing.) Well that's awesome because at least there's (A) a paper for this (grokking it is another matter) and (B) seem…

lo-res being the key :) I can see how the voxel representation would be computed and made resident in GPU memory. What's amazing to me, that such a highly branched computation algorithm is now possible in real-time on a GPU! (we had branching available since SM 3.0 - but was "not recommended")

Re: Gorgeous Unreal Engine 4 brings direct programming, indirect lighting

#78

Post by [deleted] » Sat, Jun 09, 2012, 1:03 PM UTC

photon137 wrote: post #77

dualogy wrote: post #75

Earlier quoted context omitted.

Turns out it IS voxels! https://twitter.com/Icare3D/status/211404654062481408 (Of course the (fairly lo-res compared to your screen) voxelized geometry representation is not rendered directly to screen ala Atomontage or Gigavoxels -- the the GI is based on RT scene voxelization and approximate cone-tracing.) Well that's awesome because at least there's (A) a paper for this (grokking it is another matter) and (B) seem…

lo-res being the key :) I can see how the voxel representation would be computed and made resident in GPU memory. What's amazing to me, that such a highly branched computation algorithm is now possible in real-time on a GPU! (we had branching available since SM 3.0 - but was "not recommended")

[deleted]

Re: Gorgeous Unreal Engine 4 brings direct programming, indirect lighting

#79

Post by rsaarelm » Sat, Jun 09, 2012, 3:17 PM UTC

At this point, seeing this kind of extremely high production value animation used to enact this kind of fantasy scene instantly makes me think of hackneyed backstory and plot focus-group optimized to death to appeal to slightly dull 14-year-olds. You don't throw out that sort of development budget to try out something with even a hint of narrative experimentalness, and you can always rely on there being kids with disposable income who haven't yet been saturated with cliches to the point of fatigue.

"This looks very well done, it's probably bad" is a strange heuristic to have.

Re: Gorgeous Unreal Engine 4 brings direct programming, indirect lighting

#80

Post by mgkimsal » Sat, Jun 09, 2012, 3:40 PM UTC

We've certainly come a long way since Demon Attack and Pitfall! :)

I remember 23 years ago, trying to do 'ray tracing' on my Amiga would take... hours for one frame. It looked pretty good, but... wow. This is jaw-droppingly cool.