Sandbox white albedo is gray?

#1

Top three spheres on the left should be white, not gray.
Two large spheres on the left just below the three should also be white.

Model exported from 3ds Max 2018.4 using Max2Babylon 1.3.33

IBL is the Doge courtyard, processed via IBLBaker to create the blurred MIPs for environment lighting. I used this to compare the Sandbox environment lighting with the one used in the Khronos WebGL Reference Viewer. (http://gltf.ux3d.io/)

Top to bottom:

  1. Sandbox with Doge IBL.
  2. Same, but with the Base Color texture boosted to Level 2. This seems closer to the expected brightness.
  3. Khronos WebGL Reference Viewer:

I don’t have permissions to upload the GLB nor IBL. But this should be fairly easily reproducible.

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Should we change the sandbox default environment?
#2

Pinging @PatrickRyan

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#3

Also compare the sphere white values to the white values on the emissive bars on the left. The spheres are looking pretty dark.

If the sandbox had a punctual light (like Khronos’ viewer has) that might help with evaluating brightness levels.

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#4

@echadwick-wayfair is it possible to have more info about the models?

Here it looks correct that a fully none metallic white sphere in a grey environment looks grey, actually with a white furnace test a white sphere in a monotonic grey env is not visible.

I am wondering why do you think they should be white ?

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#5

Also could you try without tonemap ?

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#6

Also it looks like the env diffuse used in the ref has been baked from a blurred cube and not relying on harmonics. I remember having those kind of visual using ibl baker diffuse env map.

It also sounds that the ref viewer relies on a none energy conservative model here for the ibl part is it ?

Would be amazing if you could share the model and exr or dds source of your env ?

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#7

Adding @bghgary as well for the ref viewer part.

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#8

I’m a new user, so I’m prohibited from uploading attachments. Do you have a preferred alternative for uploading a GLB as a ZIP, also how to deliver the EXR and DDS of the IBL?

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#9

You could share on onedrive, dropbox, or gdrive so that we can double check locally. glb as a zip is totally fine and the same for the dds or exr :slight_smile:

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#10

A similar dimming occurs in the Sandbox with the default IBL.

How do I disable tonemapping in the Sandbox?

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#11

There is no tonemapping by default in the sandbox you could try to disable it in the other viewer ?

It kind of look as expected in the sandbox as to create the diffuse part of the ibl the entire texture is basically blurred so you arrive with a luminosity close to the average one of the in use pixels.

so a white sphere in ibl will appear roughly as the average of the map. I will never the less dig in to ensure I am not missing anything.

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#12

Tonemap is disabled in the other viewer, it’s set to Linear.

In the Sandbox, the IBL has a bright light source behind and above the camera angle. So the three small spheres on the left should be white, at least on their tops.

Either that, or your IBL has been clamped.

ZIPs of all the assets.
https://drive.google.com/drive/folders/1Jpi32D4RiOHOeEKKpYkEZ_vdAUOGojEO?usp=sharing

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#13

Perfect thanks for the assets I will look into into it now.

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#14

@echadwick-wayfair is the dds a processed one or just a conversion of the hdr file ?

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#15

HDR was loaded into IBLBaker, processed with default settings (to create diffusely-convolved MIPs), then the DDS was saved out.

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#16

For the sake of it, you can now add point light in the sandbox by rightclicking on the Nodes element

You can then manipulate the light (first clik on the little eye and then pick a gizmo):

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#17

@echadwick-wayfair I tried a quick setup in Unity on a diffuse sphere:
image

I ll try the same setup in different tools to be sure.

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#18

Can you try it in Unity with the default Sandbox IBL too?

The Doge IBL doesn’t have a sun in the shot, so there’s no strong light source. Which is preferred when we use a punctual light for the main light source.

But the sandbox IBL has the sun actually present in the shot, so it should in theory create strong directional diffuse + specular lighting.

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#19

But i am confused i am using the same ibl in unity and the sandbox to compare. Were you using a different one for the sandbox ?

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#20

This is the default IBL

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