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  • replied
    tim - thank you for taking the time to explain.


    (10 With the Denoiser, I will say that what you actually wrote as a response would be extremely valuable if it was in the document, as follows....I also added a disclaimer in parenthesis:

    "
    If users want to find the Denoiser commands, they can open the console and type in "denoiser". You'll see a list of commands come up that you can adjust.
    (*Note - settings and operation are under development and subject to later change, modification of these settings is not otherwise recommended.)

    --Your Denoiser Commands image you posted above--
    "

    PS - I now read on how to use the CMD after seeing your response, newer users may not know how to do that, so a screenshot showing the command and then the number being entered would be helpful.

    Also, the reason I asked even in the first place is is that Denoiser is in fact mentioned in the document, but then operation not described. So you are left wondering what you need to do.
    Plus, in the forums it is widely discussed as being used, but as guide does not make reference to operation, users like myself are left trying to figure out how to use.
    For example, I read in forum that the max setting is 4, while 0 is off. I have no idea if this is correct, so it is trial and error. But at least I can access the commands.

    It is strange, I was expecting there would be just one overall 'Denoiser', but I see that there 18+? Meaning you have to turn on and off each one?
    If so, quite a rabbit hole indeed. But this is a good thing, because it is under development and users can provide ideas upon trialing.
    For example, if it is an individual on/off numeric value for each one, I have an thought that there could be a 'master on/off' cmd that turns on/off all, to make it simple for users.


    (2) With the Auto Exposure, you gave a perfect explanation. But I will tell you why it wasn't working. I wasn't viewing the scene from inside the Post Processing 'box'. In other words, whenever I crossed into and out of the Post Processing box, the 1 to 1 setting was activated, or was disabled. Thus now knowing this, really what I should have done was make the Post Processing Box giant to geographically cover my viewport camera location as well as main scene contents. Then me turning off Auto Exposure would have been applicable no matter how I viewed my scene.

    But see I thought this was some weirdness with the Raytracer, but it's not, it is my own user-error in not gauging the size of the post processing box properly.


    But thank you so much, very valuable info you gave...Much appreciated!!!!
    Last edited by Daffrendo; 05-14-2019, 02:50 PM.

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  • replied
    Hey Daffrendo,

    I worked on the docs for the Ray Tracing features. The command line info on Denoisers (and even the in-depth look at how Denoisers work) was left off the table for this release simply due to time and that these features are early access, meaning they are not yet complete and will be improved.

    I wrote the documentation with the intent to give enough information for people to work with to understand the gist of what is going on without going too deep on something that isn't finalized yet. 4.23 and 4.24 will continue to show improvements to Ray Tracing features and for some features like GI, new methods are being tried to improve the look, quality, and performance there. For Denoisers, these will still see improvements as well, so again, no reason to do in-depth coverage there if I'll potentially need to rewrite or rework a lot of those pages.

    For Denoisers, for systems and features that are very artist-driven, like Ray Tracing, I tend to not document a lot of command lines that aren't useful for non-programmers. I've found that doing so can often lead to more questions than answers when someone goes down a rabbit hole making adjustments to them. That's not to say that these should never be documented, I just have a particular audience that I'm writing to that this type of information causes more frustration than resolution. Programmers tend to find this information and run with it without simplified explanations and comparison images that lose context without in-depth text.

    If users want to find the Denoiser commands, they can open the console and type in "denoiser". You'll see a list of commands come up that you can adjust.
    Click image for larger version

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    IMO, pictures aren't always the solution to make something easier to understand either. If I were to show a comparison picture of each of these commands, I don't think would be a good use of time. Artists or designers should probably not be adjusting these setting. This is why we expose a lot artist and designer-friendly commands to the UI. Such as Lights being able to set the number of samples per pixel, or in the Post Process giving you control over Reflections, AO, GI, and Translucency with a number of properties that adjust command line properties.

    For Auto-Exposure, you can disable this in one of two ways:

    1. In the Level Viewport, click Show > Post Process > uncheck the box next to Eye Adaptation (this is Auto-Exposure). This will disable it for the Viewport only. This is an Editor only change so using PiE will not cause auto-exposure to be disabled.

    2. You can set an Exposure Min/Max in your Post Process Volume. The min and Max default to 0.03 and 2 however, if you want consistent exposure, you can just set the Min and Max to 1.0 to not have it changing the exposure levels when you look at dimly lit areas vs brightly lit ones.
    Click image for larger version

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    I hope this helps to some degree. Feel free to tag me here or shoot me a message here on the forums and I'll respond when I can.

    Tim

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  • replied
    Guys, no one else seems to say this so I will-

    How do you use denoiser in Command line?
    It is not referenced how to use Command Line at all in this doc. Just show a screenshot with an example so users can easily access the tool.
    I am dumb and have no idea, but a picture would make it so simple.

    PS - Auto exposure in dark scenes is non-stop when raytracing.
    Min Max have to be adjusted by default, it fights you constantly, again in a dark scene.
    You need to dimly light your scene somewhat off screen in order to deactivate it almost. Why is this necessary to constantly have to battle auto exposure.
    If there is a way to shut it off, show in this document PLEASE, again screen shot, not words. Unreal's words are too slow. A picture is FAST.

    THX!
    Last edited by Daffrendo; 05-14-2019, 03:53 AM.

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  • replied
    Thank you Epic team for the technology implementation and for the document.

    I have created a blueprint to configure all those settings with only a very few clics and within seconds to all lights and post process settings of any whole scene: https://forums.unrealengine.com/comm...fied-blueprint

    In addition I have made a little and simple Ray Tracing benchmark, but very useful, I think. So if you want, you can measure your computer power with it and even share the results with the rest : https://forums.unrealengine.com/comm...testers-wanted

    Best regards!
    Last edited by Miguel1900; 05-02-2019, 07:21 AM.

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  • replied
    Originally posted by thejturner View Post

    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.
    Ah perhaps not though the arifacts look remarkedly similar.

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  • replied
    Originally posted by Pixeldamage View Post

    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.

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  • replied
    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)

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  • replied
    Originally posted by thejturner View Post
    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)

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  • replied
    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.

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  • replied
    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.

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  • replied
    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?

    Click image for larger version

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  • replied
    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.

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  • replied
    Originally posted by etiles View Post
    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.

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  • replied
    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,
    Last edited by etiles; 04-17-2019, 04:46 AM.

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  • replied
    Originally posted by SonKim View Post

    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.

    Click image for larger version Name:	RTGI_OFF.jpg Views:	1 Size:	276.5 KB ID:	1608151Click image for larger version Name:	RTGI_ON.jpg Views:	1 Size:	278.5 KB ID:	1608152
    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

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