Ray Tracing Overview - Unreal Engine 4.22 Preview

[Antidamage]

If you're getting lots of noise turn up your light sources and adjust the result with auto-exposure. All of the tricks you use to improve path tracing will work with RTX.

[Czaja91]

If you're actually using the render as an asset can you take it into photoshop and run Dust & Scratches on it?

Dust & Scratches and some additional photoshop denoising can improve quality, but still, it would be rather bad quality, especially with textures on, when you can't go aggressive on blurring.

how you achieve this with 1070
my 1060 has two much noise
are you using skylight for this scene or something else ?

I used only default set of UE lights - directional ligh and skylight.

[Dimax3dd]

Good day! I perform raytracing tests on the RTX 2070, managed to get rid of the noise, but in no way could I get rid of the glow around some objects ((can they tell me how to cope with this? What would I not change PTX settings, nothing helps

[hidayetcifci]

At the current state of development is it possible to achieve good looking pathtraced still images? I'm using GTX 1070 and my simple test scene can't get any further than that (white spots won't go away).

Hey Czaja91. My English is bad. So I'm sorry, please. Path tracing is active with 1070 graphics cards. But even though I have made all the instructions, he's not active. How can I do that. ?

[SonKim]

Good day! I perform raytracing tests on the RTX 2070, managed to get rid of the noise, but in no way could I get rid of the glow around some objects ((can they tell me how to cope with this? What would I not change PTX settings, nothing helps

Are you lighting your scene with a HDRI or skylight? Are you using RTGI? I had similar issue with skylight + RTGI, you'll get halos and other artifacts...so I disable skylight.

Try isolating the rendering features and light to see what is causing the problem. Try lighting with lights, turn off everything else(RTGI,reflection,AO,post process).

edit: I think it's related to the RTGI(it's really experimental feature). See my attached pics. The one with the black arrow is RTGI = ON, the other one is RTGI = OFF.

[Dimax3dd]

Are you lighting your scene with a HDRI or skylight? Are you using RTGI? I had similar issue with skylight + RTGI, you'll get halos and other artifacts...so I disable skylight.

Try isolating the rendering features and light to see what is causing the problem. Try lighting with lights, turn off everything else(RTGI,reflection,AO,post process).

edit: I think it's related to the RTGI(it's really experimental feature). See my attached pics. The one with the black arrow is RTGI = ON, the other one is RTGI = OFF.

Thanks for your answer, I tested all the functions, the loop disappears when the GI turns off and when I turn off the shadows. I attached a video for understanding. I do not use HDRI in my stage and there is no glass, quality changes do not affect this loop. You have visible artifacts on your image, they are visible when I move the camera
https://youtu.be/MnoXrQ2U2Uk

[etiles]

Hello all,
Is it possible to have more information in order to recreate the "post process ray expense" material of which talks Sjoerd De Jong about in his GDC conference?
You can see it at 22'00 in the video.
https://www.youtube.com/watch?v=EekCn4wed1E

Thanks,

[NilsonLima]

Hello all,
Is it possible to have more information in order to recreate the "post process ray expense" material of which talks Sjoerd De Jong about in his GDC conference?
You can see it at 22'00 in the video.
https://www.youtube.com/watch?v=EekCn4wed1E

Thanks,

I think that postprocess material just use the SceneTexture node selecting Roughness and giving a different color grade for each roughness value range, nothing too fancy.

[NilsonLima]

etiles When you are at the editor, at the viewport click on the Lit menu, then take a look at Ray Tracing Debug options. If you choose Roughness, it will be basically the same as Sjoerd De Jong showed at GDC, but in grayscale. The diagnostic for the scene is the same, with Black color meaning fully reflective and White color fully Rough, so you need to check the intermediate of those gray shades.

[etiles]

Thank you Nilson. I thought it was something more complex like the "PBR validate" from substance or something like that.
By yhe way, I notice something strange that i don't understand.
When ray tracing is enabled, values that are read are those in the RayTracing buffer visualization, right? But I guess values are supposed to be the same : a value of roughness=0.5 is the same whatever if raytracing is enabled or not.
Here is what the roughness value is for the same material. Traditionnal buffer on the left, and RayTracing buffer on the right. Why thereis a so huge difference between both?
I checked other value as BaseColor, Specularity, Metallic, and values seems to be the same. Difference is noticeable only with roughness.
Mmm... Is it a bug?

[NilsonLima]

etiles I agree that your findings are weird indeed, anyway I think the main point is a truly representation on the gradient embracing the meaning = extremes (black and white good) and gradient (gray are bad - sort of). Looking at an entire scene at least, it makes sense.

I wouldn't call it a bug, but someone didn't just consider that there was another visualization for roughness (someone sloppy maybe), so for coherence it should be the same, I hope someone see our comments and check this, I wouldn't make a bug submission report just for that.

[Antidamage]

That halo/outline is exactly what I was seeing in my test project. If it helps at all I have no idea what caused it, but I still have the project and it still happens.

[Pixeldamage]

I submitted a bug report and project to EPIC. I just made a blank project and made a simple scene with a sphere and the FirstPersonCharacter. I added a keyboard input event so I can increase/decrease the FOV while playing. Default editor workspace and sizing on a 4k monitor.

Here's screenshots of the scene at 90 FOV and then zoomed in. You can see pretty aggressive stairstepping on all edges but it almost appears as if you are looking through a glass window. Where each square cell is slightly offsetting and refracting the image behind it (the squares don't move, they seem a fixed pattern). Curious to know what's going on. Whether it's just a fixed limitation or something we can mitigate?

I'm also getting aggressive stairstepping. It seems related to scene scale as zooming out in a huge scene results in massive pixels where the entire scene becomes a few dozen squares (on 4.22.1)

[George Allan CS]

I've had another look and it seems that the stair-stepping issue is related to how far objects are from the world origin (and therefore an accuracy problem). To test:

1. Create a cube
2. Enable the Path Tracer
3. Move the cube 100,000 units in X (or Y/Z)
4. Problem is clearly visible (wobbly / stairstepping edges)

[thejturner]

I'm also getting aggressive stairstepping. It seems related to scene scale as zooming out in a huge scene results in massive pixels where the entire scene becomes a few dozen squares (on 4.22.1)

Are we talking about the same stair-stepping? What I'm seeing is only happening in ray traced reflections themselves (not path tracing). So make a 100% reflective sphere and look at the reflection of the character pawn in the sphere. I also zoom in so the whole reflected sphere fills the FOV. Then it becomes very apparent.

I just tested 4.22.1 today and I'm seeing the same results unfortunately.