Panorama artifacts

[Amerio.Stephane]

Hello

When using a panorama rendering, there can be some very strong visual artifacts at the joints of the cube-mapped scene. See below:

- The bottom face does not have the same exposure settings as the other.

- The bright glowing halo around the white orb (billboard) above the test ball appears splitted

- there is a black line separating the front faces when the window is resized. If the window is not resized, this line is not visible

- when the camera is rotating, a seam is visible vertically (even when the black line is not visible), similar to a scanning effect on an old CRT, but vertical:

- the reflection/specular changes abruptly from a front side to the other

I understand why these artifacts are present, but I think they should be mitigated through some kind of blending.

Thank you.

 

[morbid]

Hello, Stephane!

All of these artifacts are caused by post effects.

Open console and try these commands:

• render_exposure_mode 0 (this disables adaptive exposure and you may want to set exposure manually - render_exposure 1)
• render_bloom 0 (disables bloom)
• render_ssao 0 (screen space ambient occlusion)
• render_ssr 0 (screen space reflections)

Please tell me if this helps.

Black line presents only in some custom resolutions in windowed mode. I'll report this.

Thanks for feedback!

[Amerio.Stephane]

Hi,

You are right. I also had to disable motion blur.

Shouldn't all the post effects be applied on the panorama, instead of the individual cube faces?

Conversely, the camera facing billboards are all wrong in a panorama, as they look very tilted, and looks cracked when going from one face to another.

[morbid]

Hello,

sorry, I forgot to mention motion blur.

Panorama mode uses different cameras to render final picture. All post effects are applied to each camera independently. In general, post effects couldn't be used with panorama by design.

I need some time to check the billboards, I'll write as soon as I get some result.

[morbid]

Hello, Stephane!

Good news is that we've fixed bug with black line.

I also looked into the billboard issue and I'd like to ask you a couple of questions:

• Did you mean by "cracked" the appearance of emission in panorama mode?
• Could you please show how exactly billboards are tilting? Maybe I'm missing something here.

Maybe it would be easier to attach small test scene.

 

[Amerio.Stephane]

Hi,

The 'broken' aspect is independant from the emission. It is due to the "Screen aligned" state of the billboard. I understand this is due to the billboard being drawn in separate faces of a cube, aligned with these faces. But then it doesn't look 'screen' aligned in panorama mode, and looks broken/split when spanning two faces.

As the same scene may be rendered both in panorama and in normal view, maybe a workaround would be to disable the screen alignment on your side, or to change how it is drawn?

 

[morbid]

Okay, I see.

13 hours ago, Amerio.Stephane said:

maybe a workaround would be to disable the screen alignment on your side

Maybe I misunderstood you, but you can disable screen alignment in billboard material to avoid this artifact.

Don't you mind if I ask you why have you choosen panorama mode? Is there any specific need for this?

[Amerio.Stephane]

Sure :) We'll need to simulate a fish-eye camera view (hence the panorama mode) for an embarked vision system, and at the same time the same scenery will have to be displayed in an Out The Window dome screen with soft-blended overlapping edges. In the latter, the soft-blending in projectors will hide away the screen-alignment issue. But for the fish-eye, most probably I'll have to disable the screen alignment through code.

The screen align is used because it give the best aspect when simulating halo around airport lights. Not that critical :)

I just wanted to point out that some features are noticeably "not well rendered" in panorama mode, and may need some workaround/special documentation.

Thank you.

[silent]

Quote

I just wanted to point out that some features are noticeably "not well rendered" in panorama mode, and may need some workaround/special documentation.

Yep, thats due to compex multiple cameras that used to provide panoramic rendering. There are simplier solutions available (basically, simple shaders) that can do a fisheye using only a single camera. Maybe it will be sufficient for some usecases.

Doing the real 4 to 6 camera render a correct fisheye image will alway cause some difficulties with rendering due to independed cameras that knows nothing about each other. If we will eventually found a better solution to panorama rendering we will surely implement it :)

Thanks for the feedback!