Chaos Corona Forum

Chaos Corona for Cinema 4D => [C4D] General Discussion => Topic started by: edub on 2022-10-28, 22:05:28

Title: v9 Corona Sun not always rendering (pos. driven by Xpresso from C4D phys sky)
Post by: edub on 2022-10-28, 22:05:28
I am using some Xpresso to drive the Corona Sun position from the C4D Physical Sky (Time and location parameters)...  this is purely for the positioning of the Corona Sun, and should have no other effect.  Yet, when I am test rendering in VFB - most times the Sun will not actually render, unless I make some changes to the time/ and location parameters...  sometimes I will click forward an hour, and back again - sometimes it works, sometimes it doesn't... 
I am not sure if this is the only case of the Corona Sun not rendering, but if so - what could possibly be the reason? 

I am not really knowledgeable in Xpresso, so perhaps it's something with the priority settings, which are currently set to "Expression - 0"

Any help appreciated, or if someone can confirm any issues with Corona Sun, that would also be useful.
Title: Re: v9 Corona Sun not always rendering (pos. driven by Xpresso from C4D phys sky)
Post by: Beanzvision on 2022-11-03, 14:41:49
Hi there, are you able to share a test scene for us to look into further?
Title: Re: v9 Corona Sun not always rendering (pos. driven by Xpresso from C4D phys sky)
Post by: edub on 2022-11-10, 22:44:16
I tried isolating out just the sun + XPresso setup, but when testing I am not able to reproduce the situation of the sun not actually rendering.  However, I noticed that there seems to be a refresh issue, with the sun position not updating in the VFB, unless I click somewhere else in the interface - this somehow "triggers" the correct sun location.
I'm attaching my test file.
For clarification, the XPresso setup is just a rangemapper function that drives the rotation of the Corona Sun, via a null placeholder in the C4D Physical Sky "Custom Sun Object" slot (FYI, not my setup, but I forgot who made it originally)
Title: Re: v9 Corona Sun not always rendering (pos. driven by Xpresso from C4D phys sky)
Post by: d4l1 on 2022-11-11, 10:07:00
I recently tried to connect the Corona Sun to the default C4D Sun with its Sun Expression to define the day / time myself.
While testing it out I ran into the same problem, at least while I had the viewport rendering up and running ... the script didn't update the position for the Corona Sun as long as the rendering was active.
After I noticed that I switched to the non-live type of rendering everytime I changed the values :) Worked like a charm afterwards.
Title: Re: v9 Corona Sun not always rendering (pos. driven by Xpresso from C4D phys sky)
Post by: Beanzvision on 2022-11-23, 07:57:58
Does just putting a C4D sun tag on the Corona sun object also work in this case? Without the need of Xpresso?
Title: Re: v9 Corona Sun not always rendering (pos. driven by Xpresso from C4D phys sky)
Post by: Stefan-L on 2022-11-23, 11:28:04
the c4d sun tag doesn't provide fully correct sun positions,

only the the sun from c4d physical sky does give real useful data (that is  why many connect that via expresso)
Title: Re: v9 Corona Sun not always rendering (pos. driven by Xpresso from C4D phys sky)
Post by: Beanzvision on 2022-11-23, 11:35:20
Thanks Stefan, I appreciate the info ;)
Title: Re: v9 Corona Sun not always rendering (pos. driven by Xpresso from C4D phys sky)
Post by: Beanzvision on 2022-11-23, 15:33:23
To help us understand this ''visually'', could someone post a short of vid of this not working? Thanks in advance :)
Title: Re: v9 Corona Sun not always rendering (pos. driven by Xpresso from C4D phys sky)
Post by: d4l1 on 2022-11-24, 09:12:15
TBH, never tried to simply add the Tag on the Corona Sun Object, but after a really quick test it looks like its working too :D
Was kind of proud about my first working XPresso tag so I may keep it a while ... but nice to know that there is a way simpler solution.

Recording a video is sadly not possible right now, but there may be other replies as well.
Title: Re: v9 Corona Sun not always rendering (pos. driven by Xpresso from C4D phys sky)
Post by: Stefan-L on 2022-11-24, 13:52:22
"To help us understand this ''visually'', could someone post a short of vid of this not working? Thanks in advance :) "

Please just believe it, i am c4d user since c4d 6.
the inaccuracy of the old and outdated c4d sun tag is a know fact among c4d users since 10+ years.
p.e. itc can fail/changes if PC clock isnt right, or with from pc to pc, it has incorrect positions for the locations, no saved city locations at all etc, so not usable for real archviz if you need correct and save sun positions. there is a reason maxon made the new sky many years ago.

on the other hand the physical sky provides very exact location data and is working reliable.

it woudl be better to find out why the expresso tag isnt working for the customer ( i cant reproduce any problem here so far, but we i assume edubs report is right, he is also a very experienced c4d user since many years)
Title: Re: v9 Corona Sun not always rendering (pos. driven by Xpresso from C4D phys sky)
Post by: Beanzvision on 2022-11-24, 14:38:52
it woudl be better to find out why the expresso tag isnt working for the customer ( i cant reproduce any problem here so far, but we i assume edubs report is right, he is also a very experienced c4d user since many years)

Hence why I asked for a video. ;) I don't use xpresso so my knowledge of using it is limited. A video of it not working the way it's meant to would be very useful. It's already been logged, but attentional info can never hurt.
Title: Re: v9 Corona Sun not always rendering (pos. driven by Xpresso from C4D phys sky)
Post by: Stefan-L on 2022-11-24, 19:23:33
why should i make a video from the sun tag?
- it is not related and no replacement for the reported problem.

you can also see and check the maxon manual to see the quite bigger difference between sun tag and physical sky object in c4d, alone from features.

the report says there is an issue with with corona sun and the c4d physcal sky/sun(the real one) when linked via expresso .
this has nothing to do with the old/outdated sun tag,
and using the sun tag is just no solution for the reported issue, that's what i pointed out.
Title: Re: v9 Corona Sun not always rendering (pos. driven by Xpresso from C4D phys sky)
Post by: maru on 2022-11-25, 15:01:05
Hey guys, could you please provide simple reproduction steps for this problem? I know that we already have the scene, but we need an "explain like I'm five" version, for example:
1. Open the scene
2. Select object X
3. Start interactive rendering in the viewport
4. Change value Y
5. Observe that IR is not updating

Thanks in advance.
Title: Re: v9 Corona Sun not always rendering (pos. driven by Xpresso from C4D phys sky)
Post by: d4l1 on 2022-11-28, 11:39:33
If using my own XPresso tag to sync both positions I've noticed that the IR not updating only happens while both sun objects are active and casting shadows. (Normally you won't have two suns enabled anyway, but that was only for comparison :) )
Title: Re: v9 Corona Sun not always rendering (pos. driven by Xpresso from C4D phys sky)
Post by: edub on 2022-12-15, 00:58:51
Hey guys, could you please provide simple reproduction steps for this problem? I know that we already have the scene, but we need an "explain like I'm five" version, for example:
1. Open the scene
2. Select object X
3. Start interactive rendering in the viewport
4. Change value Y
5. Observe that IR is not updating

Thanks in advance.

Sorry - I've been too busy to look further into this, but I appreciate the attention.  I will try to get a movie uploaded which shows the issue
Title: Re: v9 Corona Sun not always rendering (pos. driven by Xpresso from C4D phys sky)
Post by: Beanzvision on 2022-12-15, 10:05:37
Hey guys, could you please provide simple reproduction steps for this problem? I know that we already have the scene, but we need an "explain like I'm five" version, for example:
1. Open the scene
2. Select object X
3. Start interactive rendering in the viewport
4. Change value Y
5. Observe that IR is not updating

Thanks in advance.

Sorry - I've been too busy to look further into this, but I appreciate the attention.  I will try to get a movie uploaded which shows the issue

Thanks! That would be great!