Killzone 2 technology discussion thread (renamed)

Its interesting but RSX is'nt G80, GG are just very talented developers and have just found a way to do it on DX9 hardware, maybe or maybe not with Cells help. What about HDR? if they are doing MSAA does'nt that meen they cant be useing HDR? Well FP HDR atleast? Or maybe there using a completely custom colour space and renderer that allows then to have deffered rendering + AA + HDR?

 

IIRC, from the Killzone thread in the general console forum, it was suggested that using MSAA with deferred shading is likely enabled by the absence of API restrictions that might exist with DX9 in the PC space, rather than anything on a hardware level. I'm working off memory, though, so I'm open to correction on that.

Doesn't indicate one over the other. Indirect lighting accounts for the contribution of light reflected/bounced by surfaces, and not just the direct contribution of light sources..but whether your dynamic range is high or not is a separate matter.

It sounds like the stuff presented in the Edge tools (in fact, IIRC the GDC Killzone demo was at partially pitched as a visual 'face' of Edge, so that would make sense). It sounds like they may also be doing some vertex shading on the CPU, beyond culling etc.

Most of this is being discussed in the other killzone thread, really..

 

They ought to be calculating indirect illumination from HDR values, as that's a principle factor to indirect illumination. Walls have to be reflecting very bright light to illuminate other surfaces by a detectable amount. If the engine is lighting in HDR, indirect illumination is bound to be HDR also. TBH I can't imagine an indirect lighting solver that isn't HDR! Does such a thing exist?

 

Is that an issue of computational precision versus preserving dynamic range in your rendered image (via higher precision surfaces or other means)? We had higher precision in shader computation before, or separate to having higher precision surfaces, so there may be a distinction to be made there. I'm just guessing really, though..

 

Using Cell for vertex shading and only RSX's pixel shaders? That would get you really far!

 

I'm sure they're not idling RSX's vertex shaders. But they may be supplementing them, and more likely still, doing geometry manipulation that would be difficult or impossible to do on the vertex shaders. Some of the descriptions of the video shown at GDC might suggest where Cell could be playing a role in geometry manipulation. e.g.

If that's truly dynamic/physically modelled, it might suggest that Cell is altering model geometry..it possibly makes more sense to do that on a CPU if there is creation and destruction of geometry involved.

(As an asides, it sounds like a demo I was considering trying to implement a while ago, whereby you'd have a box and could riddle it with bullet holes that were actually holes rather than decals, and that would update the lighting model inside the box - all dynamically, nothing prebaked. I'm not sure if anyone's implemented something like that in a game yet at the level I was thinking of, but I always thought it would be cool for something like an in-vehicle sequence where it's fairly dark inside, and you're suddenly under attack, and can see your vehicle's armour deforming and opening up holes, with the outside light streaming in. Come to think of it, if you treat stuff like bullet holes as new light sources - which you may not, but it was one way I was considering - a deferred renderer might come in handy, since the number of light sources you have to handle could scale dramatically in that sort of context)

edit - could also make good use of a nice, dynamic indirect lighting engine. A 'bullet hole lightsource' would have the effect of a spotlight, directly illuminating only a small portion of interior (to the box, vehicle, whatever) surfaces..but for realism you'd want that light to bounce around the rest of the interior.

 

Not sure what you mean. If I give an example, you can work out which of your things I'm talking about! If there's a room with a floor rendered at mid-grey with direct illumination, and hitting the back wall is a light source, for the reflected light from the wall to affect the floor by making it perhaps 10% brighter, the actual light reaching the back wall might have to be 100x brighter than the light directly illuminating the floor (depending on attenuation, surface colour, etc.) The subtle lighting effects of indirect lighting needs to be calculated from very high relative source values being reflected. A light source of 10x the brightness of a directly illuminated surface isn't going to have much noticeable reflectance. This is what I know from photography anyhow. I don't know if these can be hacked down to a narrow dynamic range and remain convincing. Still, when you've got HDR tone mapping being applied to the direct lighting, it makes no sense (to me anyway) to render the indirect illumination in a lower dynamic range.

 

I guess, what I was wondering was, if render surface precision mattered here versus the precision of the internal shader computation. Light source values aren't being rendered out, afterall, they're just used in the computation of our pixel values. I don't know enough here to say...perhaps someone will clarify.

 

It seems like Sony will be having a 2,5 hours long demonstration of Killzone at E3.

http://kotaku.com/gaming/e307/the-e3-killzone-2-invite-272022.php

 

2,5 for just, one game¡¡? It should be the duration of the full keynote.

 

I hope it will be something special since its 2.5 hours. If the game doesnt prove itself as the mindblowing work we are expecting and lasts that much in the presentation it will be a 2.5 hour presentation of dissapointment

 

ofcourse,
does that even need to be mentioned?

 

I think this is something that will be part of the Killzone implementation. I remember reading an interview with someone from Evolution Studios (probably Scott Kirkland) who briefly mentioned that that Guerilla Games were adding some movie-like qualities to Killzone and he was obviously impressed from what he knew.

 

Its not just for one game. Its a pre-keynote-show for Sony...

 

According to Tempy at GAF who works at Guerrilla, the people invited will be split into groups and shown the game separately..it's not one big long 2.5 hour demonstration for everyone.

Also, I'd mind your expectations I think a lot of people are expecting it to fall flat on its face, to be honest.