Path Tracer Surface Reflection Issue

Started by WAS, December 23, 2020, 12:00:23 AM

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Matt

Quote from: WAS on December 23, 2020, 03:33:09 PMThat's why I mentioned some sort of global max distance for luminosity sources. Seems they're creating pollution for the renderer.

Make the background invisible to other rays and it will have exactly the same effect.
Just because milk is white doesn't mean that clouds are made of milk.

WAS

I thought you're saying to do the opposite. Though, if I add water then, it won't reflect when it needs too.

WAS

Did you mean, like, if it were a image map, have one background invisible, and a blurred source (like gaussian), and than another sphere with invisible to rays, but visible, with the "crisp" version? To retain enviro lighting?

Matt

Just because milk is white doesn't mean that clouds are made of milk.

WAS

Curious how that will look. Wouldn't be hard to export spherical maps. Reason I don't want to use a image map from elsewhere is they're all just the Milky Way, and I want to be "otherworldly"

WAS

#20
Still having issues with this in the latest version. Now, during the daytime, speckles of atmosphere are reflecting on the terrain in PT. Again, no reflection shader.

Notice all the blue pixels here. There is no blue shaders. There is the base colour shader and 0.5 white on FS and 0.5 white on surface layer masked by displacement setup.

This is definitely introduced in this latest version, and seems like a bug. All the speckle in the last image is blue-sh, and only thing blue in the scene is the sky (before the bucket is finished it's easy to see the solid blue errant pixels). Noise was common but not direct reflection like spots.

Matt

#21
Quote from: WAS on December 28, 2020, 12:22:50 AMStill having issues with this in the latest version. Now, during the daytime, speckles of atmosphere are reflecting on the terrain in PT. Again, no reflection shader.

Notice all the blue pixels here. There is no blue shaders. There is the base colour shader and 0.5 white on FS and 0.5 white on surface layer masked by displacement setup.

This is noise/variance from the path tracer. At low anti-aliasing settings the path tracer aggressively reduces the number of samples, but at higher AA or lower pixel noise threshold this should look a lot better.

QuoteThis is definitely introduced in this latest version

Have you tested in an older version to be sure of this? https://planetside.co.uk/forums/index.php?msg=283731
Just because milk is white doesn't mean that clouds are made of milk.

WAS

#22
I don't have a planetside account (still) to get any past versions, also reformatted PC for better support with TG and didn't save downloaded files. But I consistently work on surface shaders and while the PT has been noisy, have never noticed blue speckles from the sky ever.

You can still plainly see the speckles at AA6 and AA7, though, Matt. In  fact, you get more of them. Lol And AA7 is fairly noise-less for me, but still can see plain blue speckling independent of noise.

I'm not sure why you can't see an obvious issue that would have been complained about previously if their shaders are being messed up with blue speckles form the sky, or stars. Noise was always common, in shadow, and light, but not reflection speckles of solid colour from a source (sky, stars, etc). Shadows are bluish cause of ambient lighting and the sky, but the solid bright reflection like pixels are errant.

JPEG kinda kills the blue but all the "white" speckling is the blue.

WAS

#23
I would have obviously noticed such an annoying issue before that literally triggers my OCD. lol It now seems AA7 isn't even good enough. PT should be balanced for quality, on a scale similar to standard.

IMO the Path Tracer is currently broken and won't be using it. Can't have stars suddenly, atmosphere speckling a nearly flat terrain. Just bad.

Too me it seems obvious the new specular models are st fault, as that is a significant lighting model change and im sure PT defaults to one of them when no shader specifies one?

Matt

Quote from: WAS on December 28, 2020, 03:10:57 PMI would have obviously noticed such an annoying issue before that literally triggers my OCD. lol It now seems AA7 isn't even good enough. PT should be balanced for quality, on a scale similar to standard.

It's partly caused by the low albedo of the surface, and the optimisation choices the path tracer makes for low albedo surfaces. They aren't optimal for large open areas without texture. You can compensate for this by increasing the path tracer's "Max samples" to something like 100. Combine this with AA 8 and a PNT < 0.01, or whatever you prefer, and it should be possible to make a fairly clean image. In a scene with more texture you won't need to go that low. But there is room for improvement in the renderer, for sure.

QuoteToo me it seems obvious the new specular models are st fault, as that is a significant lighting model change and im sure PT defaults to one of them when no shader specifies one?

It might seem obvious but it's not true. Most of the shaders don't have a specular model and they are not relevant to your scene, but I tested your TGD to make sure and it renders about the same in 4.4 and 4.5.
Just because milk is white doesn't mean that clouds are made of milk.

Matt

Quote from: WAS on December 28, 2020, 02:57:52 PMI don't have a planetside account (still) to get any past versions

Your license was created outside of the store, but if you create an account I will reassign your license to your account. You can do that here:
https://planetside.co.uk/returning-customers/

You might already have an account from downloading free versions, so try logging in with that first.

After you've done that, let me know and I'll create a replacement license.
Just because milk is white doesn't mean that clouds are made of milk.

WAS

Will we be getting any more samples from that max samples option? I believe I remember you saying you may add higher options cause of the noise we were getting in heavy shadow on SSS? I know lowering the PNT really hits the render hard. When I ramp up max samples, I don't see as heavy a impact on render time as messing with AA customization. Maybe that would also help here without going so hard on AA,which with PT at least, really hits hard.

I still feel I never noticed such hard point reflections of colour before. Noise, yes, speckling from PT in shadows, yes.