Black Sky - why? Tweet

[ArchPrime]

For some reason I cannot make my sky anything but black in Daylight Environment mode. Supplying anRGB colour or an RGB image in Environment=>Sky Color makes no difference. What am I doing wrong? Have not used Octane in a while but I don't recall this problem on earlier versions of the plugin or engine

[kxl]

Did you enabled the alpha channel in the kernel tab ?

[ArchPrime]

Hi - yes alpha channels are on

I found a workaround though - copy the ArchiCAD saved view and switch to it, then switch back
Is the requirement to do this a bug?

[kxl]

I think you should disable the alpha channel (that's why you have a black sky) .

Cheers

Stefan

[face_off]

Yes, disable Alpha Channel if you want the hdri in the background.

[ArchPrime]

Hi - but I don't want hdri - I just wanted a plain blue colour.

But following my workaround , the exact same settings now do give a blue sky.

A possibly separate issue, but I note that when viewed through coloured glass, the blue sky turns black again - for the portions with the glass in front of it

** Edit ** looks like alpha=on in Kernel was preventing plain coloured sky from working too, as switching it off and on then off again made the sky appear in both saved views.
Is there a way to have a sky rendered as part of the image and also to have alpha channel on? not sure why I would want to - but I thought alpha related to textures, not plain coloured skys?. if alpha channel is something that prevents operation of the Environment settings for plain sky, should there be some kind of explicit interaction with the sky parameters in the UI - so if alpha channel is on, sky settings are greyed out or similar ?
I note switching alpha shadows off or on seems to make no visible difference to anything. Presume there must some separate setting somewhere this parameter interacts with too?


And yes, the sky disappearing when behind coloured glass was solved by switching alpha channel off. Strange that blue sky was visible beside the coloured glass and through clear glass when alpha was on though (but only after workaround view swap trick) .. seems inconsistent somehow

Also, sunlight coming through coloured glass is not casting coloured light on the floor as it should - is this a clue about glass materials properties being wrong in some way?

One for the suggestion box: maybe a help button beside each parameter, linking to specific paragraphs and diagrams showing what that parameter does, and what it's dependencies are ? Obviously the PDF manual is a couple of versions behind and an update to this with all the latest features/parameters and working methodology suggestions for achieving common tasks would be great (perhaps culled from Paul's FAQ from time to time), but even better would be context specific help. The average ArchiCAD user (who might do a rendering once every several months) won't want to look much farther or harder for info on the octane plugin than they do for the documentation that comes with the rest of ArchiCAD's plugins

[rappet]

Hi - but I don't want hdri - I just wanted a plain blue colour.
...

When alpha channel disabled and you use the daylight environment (just like your printscreen) you won't get a hdri for backgournd but the colors you set for the sun.
When alpha channel enabled try and put blue background image in postproduction to see what happens to transparant materials?
The render viewport shows black ofcourse as being transparant (for postproduction)

[ArchPrime]

Hi thanks Rappet

I think I get the general idea behind alpha channels - though I tend not to do post production myself (untll now my main interest is in animations).

My issue is when no HDRI or standard texture is involved in creating SkyColour - just a fixed RGB colour, or an RGB gradient. If alpha is selected, why is the sky colour parameter even available? Why also does sky behave differently depending on whether you have exited and returned to the view as described?

A weird thing also is that in this simple case, clear transparent material shows blue RGB sky beyond, while non clear glass shows black sky beyond when alpha channel is on. When alpha channel off, both show blue sky beyond glass as one would intuitively expect (obviously the blue is tinted in the case of coloured glass)

[rappet]

...

My issue is when no HDRI or standard texture is involved in creating SkyColour - just a fixed RGB colour, or an RGB gradient. If alpha is selected, why is the sky colour parameter even available?

The sky color defines not only the background color, but also the lighting on your scene.

Why also does sky behave differently depending on whether you have exited and returned to the view as described?

Can you show this by making printscreens before and after to explain?

greetz,

[ArchPrime]

...

My issue is when no HDRI or standard texture is involved in creating SkyColour - just a fixed RGB colour, or an RGB gradient. If alpha is selected, why is the sky colour parameter even available?

The sky color defines not only the background color, but also the lighting on your scene.

Good point!

Why also does sky behave differently depending on whether you have exited and returned to the view as described?

Can you show this by making printscreens before and after to explain?

Am in the middle of a long overnight render now, but will try screenshots tomorrow after work
Also of the strange coloured vs non coloured glass discrepancy when alpha is on...



Cheers