Ray Tracing Without RT Hardware

doubletake

Gawd
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Honestly looks better than some "real" ray tracing I've seen. Amazing what can be done in a shader.

Nah, I assure you, while this can look almost as good for screenshots, in motion, it's nowhere near as good without extensive tuning and sometimes strange artifacts due to insurmountable limitations. Not trying to be a downer or anything since I actually sub to MartyMcFly on Patreon and use his RTGI shader in several games, but you only have to fire up Metro Exodus or Control once to see how much better real RTGI is. Also, the SSR shader on display is really only good in indoor games like this, because in outdoor areas, it'll often fail to discriminate between what should and shouldn't get reflections, and you'll end up with things like shiny, reflective dirt and grass or other surfaces that should be mostly matte. Even the author specifically states in the shader's description that it's only recommended for screenshots, because it tries to work on everything.
 

cybereality

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fire up Metro Exodus or Control once to see how much better real RTGI is.
Yeah, I've tried a few games already BFV, Metro, Control on my 2080 Ti.

Control was the only one that I would say was a big improvement. Metro looked nice but the effect was subtle most of the time. BFV was okay but I understand it was the first game and not a great implementation.

I also played Quake II, that was pretty cool I will admit. But I think there is a place for post-process methods as of course not everyone owns RT hardware and the results are pretty nice all things considered.
 

Auer

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Yeah, I've tried a few games already BFV, Metro, Control on my 2080 Ti.

Control was the only one that I would say was a big improvement. Metro looked nice but the effect was subtle most of the time. BFV was okay but I understand it was the first game and not a great implementation.

I also played Quake II, that was pretty cool I will admit. But I think there is a place for post-process methods as of course not everyone owns RT hardware and the results are pretty nice all things considered.

Give Wolf:YB a shot.
 

noko

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Depends on the game, RTX in Control from what I've seen looks fairly decent, same with Wolfenstein Youngblood. Other games the improvements considering the performance penalty, lower resoluttion requirements, turning down other settings etc. did not look that usable particularly anything less than a 2080. Of course the narrative may change, as it should if the quality and performance changes positively, with better game support, more gamest etc.
 

IdiotInCharge

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but it could be a nice option for higher end cards or on older games to update the graphics.
I see it as fun to play with, but at that point you're playing with the shader rather than playing the game.

I'd hope that at some point, retroactive implementations like Quake II for common older engines starts to become a thing.
 
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You can see another video here (it's a Reshade plugin, so works with basically any game).


The performance drop is pretty big, but it could be a nice option for higher end cards or on older games to update the graphics.

Watched the first few mins, no way would I use that due to the performance drop. That's just my opinion though, never been big on RTX in general.
 

cybereality

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Yeah, the performance drop makes it mostly not worth it, but I would want to see how it performs with good hardware (or on old non-demanding games).

I prefer performance (166Hz here) so I will have no problem turning down settings to get smooth gameplay.
 

IdiotInCharge

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Some of us prefer performance over shadow quality, no need to be a prick.

So, trying to respond without sounding like a prick, because I'm honestly just trying to add to the conversation...

Shadow quality, while addressed by ray tracing, is really just a nice side effect. Actually needs HDR support to really shine.

Ray tracing, to me, is more about accurate lighting, to include color as well as shading and gradients.

It's that 'missing thing' that separates raster graphics and helps overcome the obvious 'plasticky' look of rendered graphics, especially in motion.


[if you know this, I'm not really trying to correct, but trying to add to the general understanding of the technology and what the benefits are]
 

5150Joker

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Speaking of RT, I finally got to test it out in Control and the performance hit with everything at max is pretty substantial at 1440p but with their implementation of DLSS 1.5 it pretty much negates it and the visual impact of DLSS is next to nothing (I couldn't really tell):


If NVIDIA can get DLSS 2.0 to work seamlessly in more RT titles, this will be the future of RT w/a minimal performance hit for Turing and Ampere. If AMD doesn't have anything similar, it's going to be in trouble.
 
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If you were trying to avoid a prick response maybe you could have said "I prefer performance" and left it at that. The minute you attacked a new technology, in its infancy, as some sort of "I never liekd X anyway", you asked for it.

No need to get butthurt over someone not head over heels for a new graphics tech. I did not ask for that response at all.
 

SPARTAN VI

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What shader are they using for the screenspace reflections? I have McFlys RTGI shader and my Black Mesa doesn't look anything like this.
 

dgz

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Found this awesome video of Black Mesa with a post-process ray tracing shader.


Honestly looks better than some "real" ray tracing I've seen. Amazing what can be done in a shader.

I was watching the video and thinking "this doesn't look right" the whole time. I almost started feeling like an ass hole, then I saw "post process ray tracing shader"...
 

SPARTAN VI

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Was doing this last night, the guide doesn't mention the screenspace reflection shader to use. If I use McFly's SSR shader, which is intended for screenshots, I get strange reflections (e.g. inverted reflection) on a lot of surfaces. I think that's why none of the footage is actual in-motion gameplay. You might get a 2-3 foot panning/zooming clip, but the majority of the Black Mesa footage is static camera angles.
 
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cybereality

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Yeah, you might be right.

I tried looking for better videos but they are pretty much all slideshows, which maybe is deceiving.
 

NattyKathy

Gawd
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the Reshade PTGI shader is pretty neat, I've been subscribing to Pascal Gilchers Patreon for a few months to support development and get access to new releases. Tried it in quite a few games and found the quality of the ambient occlusion can look worlds better than the usual SSAO/HBAO implementations and when the indirect lighting works it can add a lot visually. However it can take awhile to get the settings dialed in to strike the right balance of subtlety where the effects aren't overwhelming, and due to the limitations of the depth buffer information available to Reshade the rt effects can clash quite badly with depth of field and any sort of volumetric effects like fog and smoke so there are definitely significant caveats. Still it's pretty cool that it can be done in add-on postprocessing and that it works even in old games like Portal, Half-Life 2, even Quake 1. And the performance is- by my low low standards--playable on my Vega 64 at 1680x1050, around 45fps with everything maxed in new games or solid 60 in older titles. pretty neat imho
 

XoR_

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RT without RT hardware is a dead end due to terrible performance.
Still nice that people get in to RT in one form or another as it will ultimately will be a good thing.
 

dgz

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AKA "not really ray tracing" shader.

I mean, it's impressive for what it is but how is this ray tracing in any shape or form? It's just a saturation algorithm. Well, probably not just that since it's adding reflections and god knows what else.
 

Armenius

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Yes, it is ray tracing, but done in screen space. Screen space reflections are also a form of ray tracing.
SSR uses a technique called ray marching. This takes a ray and casts from the camera to iterate across the screen until it intersects with an object and then projects it back at the camera. It only does this a defined number of times before returning the modified pixel matrix to the shader. Ray tracing casts rays from the light source in every direction a defined number of times and then projects it back at the camera. The source of the ray and how it's projected is a major difference. Ray marching is also a deferred technique, using the geometry buffer from the previous frame or frames. Ray tracing is done in real time in the rendering pipeline, meaning the color data that any post-processing shader gets is already defined by the ray tracing process. No offense, but it is ignorant to call SSR ray tracing or a form of ray tracing.
 
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