Physical and Standard Material shading problem with orthographic camera

[alelepd]

Description of the problem

Hello there. I noticed that both MeshPhysicalMaterial and MeshStandardMaterial had a bug related to the shading when using an orthographic camera.

I made a post in the forum looking for help: https://discourse.threejs.org/t/physical-material-artifact-when-using-orthographic-camera/9243?u=avena

Here is a codepen

• codepen

And some screenshots of the issue (notice the hard edge at the left side of the spheres):

The problem occurs or become noticeable when you have big objects (like a sphere with a radius of 64 units) and move the object away from the center of the screen when using an orthographic camera.

Everything looks fine in perspective camera. Tested in r107 and r108. The issue doesn't happen in Phong or Lambert materials.

Three.js version

• Dev
• r108
• ...

Browser

• All of them
• Chrome
• Firefox
• Internet Explorer

OS

• All of them
• Windows
• macOS
• Linux
• Android
• iOS

[WestLangley]

This is not a three.js bug. Please do not repost forum help questions here.

MeshStandardMaterial exhibits retro-reflection with rough surfaces; MeshPhongMaterial does not.

[alelepd]

Hey @WestLangley sorry If I misunderstood this as a bug. But I am not doing a repost.

I was reporting the issue here because I believed the expected behavior is not happening. I think it was a little harsh to close the issue like that :(

Maybe I didn't explain the issue properly. Right now the size of the object and its position on the screen affect the way the standard material look; none of that should happen in orthographic camera, or at least I don't think that's the expected behavior.

[mrdoob]

I don't get to see the ball here...

[alelepd]

Oh. You can try by using the horizontal layout in codepen (the issue is noticeable when the object moves away from the center, that's why the sphere is so off).
I recorded another view from my local setup (using a bigger sphere):
https://jmp.sh/Vpns5Pc

[mrdoob]

Thanks for the video.

@WestLangley PBR is not supposed to look "correctly" in when using OrthographicCamera?

[sciecode]

I don't fully understand how fresnel is supposed to work when using an OrthographicCamera, but the behavior definitely doesn't look correct.

I'm just not 100% sure if there's a fix for it. I believe this should be re-opened until we have a clear answer.

[WestLangley]

I was reporting the issue here because I believed the expected behavior is not happening. I think it was a little harsh to close the issue like that :(

@alelepd Apologies for being too harsh. I will reopen this so it can be discussed further by others.

[alelepd]

Thanks @WestLangley!