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-S-7- -Raven

ArmA 2 Lightraytracing

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This topic may only be based down to a simple question, but this idea is pretty interesting. Since Crysis and some other games have this, objects in our ArmA 2 environments would literally look more vibrant. For instance, when light hits a pine tree... the blades of light from the sun seep through the object specifically the needles them selves.

This may only be a DX10 or DX11 feature, but if anyone would like to talk about this... you can talk about it here. For more information on what ray tracing is, click here.

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For future reference, this is called Volumetric light, and while I think it can look awesome, if it was all over the place in a game like Armed Assault 2 it'd be overkill; in reality you only ever see it on misty mornings, from clouds in the distance or in really dusty places

Ray tracing is something else entirely, in fact it's a totally different way of rendering 3D graphics that isn't really possible at present in terms of real time graphics (although Intel are making moves towards making a ray tracing only GPU)

Ray tracing breaks down a render scene into mathematical models of rays of light and how they react to hitting surfaces. Volumetric light is just a method of making beams of light visible

Edited by DaveP

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ray tracing in arma 2 ? no way lol... also iirc SSAO involves some ray tracing.

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ray tracing in arma 2 ? no way lol... also iirc SSAO involves some ray tracing.

SSAO uses a depth map of the image (how far each point is from the camera is represented on a sliding scale of white to black, close to far) to work out whether two points are near eachother (for example, where a wall meets a corner) and adds some shadow there. Ambient Occlusion basically says "where two objects are close to eachother, add some shadow"; it's a simplification of the advanced properties of shadows that can add a lot to a shot, be it interactive (ie. a game) or a film/video. Again, no ray tracing

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Although nothing to do with raytracing and raytraced area lights, I'm actually amazed at how it looks in the game when you walk from a sunlit area to an area where the terrain is blocking the sun. It's a gradual visibility of the shadow depending on how much "sun disc" is shown. Well done :)

I don't want volumetric shadows or god rays, not unless I can specifically control it anwyays. I'd rather have a true fog system that lessens the impact with altitude. In real life, you may see the airport well from above if it's in ground fog, but it may still be impossible to actually land on.

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God rays are pretty rare, not something you'd see in mid day. And for the performance overhead they cause, they're not really worth it.

But it would encourage soft shadows, which is something I'd wish they'd add.

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In a demonstration of the technology in Gaea Mission, they showed the godrays in action over a rock. To me, it didn't seem like a ray tracing thing.

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they should remove the sun flares, you can not see those flares at least if your eyes are made with camera lens

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Stupid me. I always thought ray-tracing was an advanced way to have the AI "see" the virtual world. You know, like virtual vision lasers that shoot from their eyes to detect things....

....

...

.:(

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Stupid me. I always thought ray-tracing was an advanced way to have the AI "see" the virtual world. You know, like virtual vision lasers that shoot from their eyes to detect things....(
Actually, that is also possible with raytracing.

Even sound can be simulated through a raytracing-like system and I believe something similar was used in Aureal 3D.

But to have raytraced graphics, things (hardware, software, games, toolsets) need to change drastically.

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they should remove the sun flares, you can not see those flares at least if your eyes are made with camera lens

Lens flares have never been visible through your character's eyes in the OFP/ArmA games. They only appear when using an external camera (with lens :p) like the 3rd person view or a scripted camera.

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Hehe, cool. Didn't know that about lens flares, but I'm doing the same thing to NVGs - not allowed in third person mode :p

God rays doesn't need raytracing, good fakes exist. And they're not that rare. All you need is a moist atmosphere with thick clouds to block the sun. Water particles will shine in the sunlight. A good CB/TCU weather (CB = thunder clouds, TCU = just before) is all you need (or dense ground fog for volumetric shadows). But for the sense of gaming a war game, I think it's a bit over the top :) Normal shadows from other lightsources would have higher priority with me.

Edited by CarlGustaffa

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Ray tracing is far more than just rays of light beams, maybe I had not mentioned. But, moving on. Ray tracing is also when light is observed by objects; and absorbed or repelled dependent on the objects color or density. If the object has dark colors, it will absorb the light. If the object has bright colors, it will repel. If the object is opaque [solid] then it will in fact show density of color depth. If the object is translucent or transparent, it will simply ignore light. What games of today do not have is color and light reflections, Crysis is simply the closest game to it. Other than Far Cry 2, but anyways... coming down to my conclusion. Movies of today, such as Avatar and other stunning 3d worlds use Ray Tracing as its primary pool of graphical effects. Other wise, it would look like something from 10 years ago that is displayed on games of today. Btw, look up Ambient Occlusion and Field of View to see a little more compatible version of Ray Tracing... it can be activated through Nvidia Control Panel in the 3D Application Settings dialog.

Here is a good example of light and color; compacting and repelling.

Image 1 [Density]

http://img265.imageshack.us/img265/9381/glasses800edit.png

Image 2

http://www.cs.utah.edu/~sparker/images/seurat/bigcbox.jpg

GTA4 Ray Tracing with ENBSERIES

http://img.youtube.com/vi/ZOQviyZ1IC0/0.jpg

[Ambient Occlusion - Edge effects]

http://scottdewoody.com/images/tutorials/occ10a.jpg

Edited by [S-7] -Raven

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Lens flares have never been visible through your character's eyes in the OFP/ArmA games. They only appear when using an external camera (with lens :p) like the 3rd person view or a scripted camera.

oh, ok I didn´t know that

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-Raven;1763038']... Why? ...
The technique is capable of producing a very high degree of visual realism' date=' usually higher than that of typical scanline rendering methods, but at a greater computational cost. This makes ray tracing best suited for applications where the image can be rendered slowly ahead of time, such as in still images and film and television special effects, and more poorly suited for real-time applications like computer games where speed is critical.[/quote']

Raytracing isn't used in real time rendering; at least not in commercial games.

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Here is an example of Wolfenstein raytraced in a intel demo:

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Stupid me. I always thought ray-tracing was an advanced way to have the AI "see" the virtual world. You know, like virtual vision lasers that shoot from their eyes to detect things....

....

...

.:(

Fail

No i kid, yeah its fancy for saying Volumetric lighting effects AFAIK

Ray tracing rendering + Arma 2 on my PC= STOMP HULK SMASH KILL KILL KILL! :Banghead:

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Raytracing is used by pretty much every shooter game out there, incl Arma. It's nothing more than shooting a ray and observing what happens to it. For rendering purposes however, now that's something different ;)

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Raytracing is used by pretty much every shooter game out there, incl Arma. It's nothing more than shooting a ray and observing what happens to it. For rendering purposes however, now that's something different ;)

Indeed, but he pretty much implied raytrace rendering (as in ultra realistic rendering).

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Yeah I know. Btw you only need raytracing for a few things:

1) Reflections on curved surfaces. Dynamic environment maps can handle it pretty convincingly at a much cheaper price. RenderToTexture could handle true reflections at least for flat surfaces.

2) True'ish refraction simulations, that is completely unrealistic for a game. There are good enough refraction shaders that deals with convincing refractions. You'd need even more if you want to split the wavelenghts realistically, but A2OA already have some decent ppEffects that simulate this, at least to acceptable levels for optics. True caustics? Forget it. Add a caustics map for the see floor and call it a day.

3) True sharp shadows and realistic soft shadows. True sharp shadows are rarely that true, as 99% of all light sources will have an area/volume instead of a point. Soft shadows can be done using shadowmaps, but the drawback here is typically view limitations and shadow bias (shadow offset from object). For gaming purposes I'd say any shadow is good enough, as long as shadows from tree crowns etc can be blurred somehow. There are probably gaming shaders that deals with multiple types, but I'm really not into the gaming aspect of CG.

4) Forget any kind of multiray system, such as scene point queries, gatherers, true global illumination, soft reflections, and true depth of field - their cost is insane.

Even if all this was possible, it would still look like crap. Because raytracing alone isn't enough to convey a realistic scene. Gone are the days where "

" was considered realistic :D Adding baked or dynamic AO(/SSAO) helps, but it doesn't do anything for indirect lighting. I'm sure there exists gaming solutions for this too (only seen it on showreels and tech demos, probably not there for my DX9 :p), but I expect the price tag (in frames) to be significant.

I guess we can dream, but frankly I don't expect a raytracing algorithm implemented for rendering for this game anytime soon.

If anything I would like to see some sort of "light occlusion" for building classes similar to "sound occlusion" we have in vehicles, and for units that are considered "inside" such building (it's already there, check how rain look different when you're inside). Only interior walls/polygons would need to be checked, and the amount of "light occlusion" would be based on how many openings the building had. It's not a true shadow calculation or global illumination thing, but in a "dark house with few windows", you would hide pretty well. At the same time global illumination would be simulated as there is some light everywhere, even if its uniform and not shadow based.

For terrain and dynamic shadows from light cones (search lights and vehicles), maybe a "reach map" (like in ACRE)? It doesn't need to examine that many positions due to the cone and already fairly limited reach, and from there it can just create a course map that is interpolated. Trees won't work obviously, but at least you can hide in shadow behind a ridge, instead of being lit up as a christmas tree.

Remaining problem, and a big one, is omnidirectional lights such as lightpoints (flares etc). I really have no suggestions on this one...

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