Light cache for animation is just the last frame?

[supposing_co]

The method I have used for animations befroe is a light cache calculated of the camera path and then an IR every 10th frame. The LC looks a blurry mess usually but its just rendeing the last frame in the animation at the moment ? I have tried using LC following camera path and then brute force but it still doest work. Wassup?

[tashko.zashev]

Hi,
Which V-Ray version is that ?

[supposing_co]

we are using 3.6.04. Like I said in the post , I am used to seeing a swirly LC calculation but it just shows the last frame

[tashko.zashev]

I believe it's the same issue discussed here
https://forums.chaosgroup.com/forum/...vray-adv/page2
We have this fixed in V-Ray Next but if you have't upgraded your plugin already, then you can render with LC in single frame mode or even better to switch to BF.
The issue is not present in the 3.5 builds but I'm not sure if it's an option to downgrade at all.

[supposing_co]

Ok Tashko, I saw that thread. So use Brute force for primary engine and LC for secondary and do one frame at a time?

[tashko.zashev]

The issue was that LC in animation mode (use cam. path) doesn't get the entire animation/camera move into account only the last frame. You can set the LC to single frame mode during the IR map Nth frame calculations - the LC data will be stored in the Irrmap file. My advice is to make a short render test to see how this works and if you are satisfied with the animation quality, before any production/final renderings. Every scene is different so you my need to make some changes.

[supposing_co]

Ok so set the frames to say every 10th set the LC to single frame and run the calculation. Then load the LC from file and render . Should I set the LC to screen or world ? When I render I should set primary engine to BF , what should I set the secondary to?

[tashko.zashev]

If you are using Irradiance map then it is not necessary to precalculate the LC first, you can do it at once. The resulting Irradiance map files will have the LC data inside, because the secondary GI data is calculated first. The for rendering stage you can set the Irr map to from file and Secondary to none.

[supposing_co]

Ok thanks , last question If I want to use BF should I just do it frame by frame?Is there any point precalcing the light cache?

[tashko.zashev]

Yes, frame by frame with BF/LC. You can find some useful information about the LC setup here :
https://docs.chaosgroup.com/display/...Cache+Settings
At the bottom - Avoiding flickering in animations
But you have to consider that the Use cam. path will not work well with builds 3.6.

[iCreate]

The issue was that LC in animation mode (use cam. path) doesn't get the entire animation/camera move into account only the last frame. You can set the LC to single frame mode during the IR map Nth frame calculations - the LC data will be stored in the Irrmap file. My advice is to make a short render test to see how this works and if you are satisfied with the animation quality, before any production/final renderings. Every scene is different so you my need to make some changes.

Hi.

I've had the same issue. I posted this yesterday: https://forums.chaosgroup.com/forum/...imation-in-3-6

It looks like I'm/we're having to re-examine our technique for rendering animations. This is very frustrating when on a deadline, which I'm currently on and I'm no closer to understanding what to do, or if what I'm trying at the moment is wasting time.

There seems to be a lot of updated information/thoughts/processes if you go trawling through posts but no official - 'this is how you should do it' ...... 'or you can do it this way'..... 'or this way will work too' advice.

As you can probably see, I'm feeling a quite frustrated.

----------------------------------

Following the above information I've set the below settings. Some are the same settings as I've always used:

Primary = IM
Secondary = LC

Here are my settings:

=IM=

Preset - Medium Anim
Use camera path = UNTICKED (is this correct? I've always used it.... looks obsolete/broken in 3.6)
Show calc phase = TICKED
Show direct light = TICKED
Subdivs/Interp = 50/50

Mode = Multiframe Incremental

=LC=

Subsivs = 2500
Sample size = 0.125m (Can you please clear this up for me? This is what I've always used... never had any issues but not sure if it's correct)
Scale = World
Show calc phase = TICKED
Use camera path = UNTICKED (is this correct? I've always used it.... looks obsolete/broken in 3.6)
Retrace = TICKED ----- Set to 2.0
Mode = Single frame

-----------------------------

So, I rendered 250 frames.

When it finished I saved the file in the IM section. This created 1 vrmap file.

I then do the following:

Secondary = NONE

=IM=

Mode= From file (load the new vrmap file)

Set increment to 1 in common.... RENDER

================================================== ======================
================================================== ======================

Please look at the link I posted above. This shows the headache I've been going through. It's nice to share the pain.

On my traumatic journey I also found this post:


https://forums.chaosgroup.com/forum/...tion-rendering

To sum this one up.... it seems to scrap precaches altogether....... My poor head can't deal with the information overload.


Thanks,


Sean

[troy@visualiii.com.au]

Sean, i see even after 2 years, you've never had a reply.
I am in the same boat. Did you end up finding the correct solution?
I would be interested to know what came of it, if you'll be willing to share
thank you

[^Lele^]

https://forums.chaosgroup.com/forum/...06#post1003906
and
https://forums.chaosgroup.com/forum/...35#post1003935

V5 removed the pre-calculated LC entirely, and while the IRMap is still present, it's officially a discouraged method.
Saving precalcu;ated caches to disk is also officially discouraged.
This, due to the needs of stuff like the LightMix and LPEs, besides others.

From factory defaults, use BF/LC, per frame, setting the LC up as needed (still or animation from the dropdown).
If on earlier V-Ray versions, you can mimic that by setting the LC to 3000 subdivs, and a retrace of 8.0, in single frame mode, for animations.

[troy@visualiii.com.au]

Thank you Lele for the reply

I would have thought that if saving precalc officially is discouraged, which for a long time i always saved out, then why not chaos group remove it completely like the flythrough mode within LC and show the new Vray way and remove any confusion that the end user would have.

At the end of the day, chaos group are driving the way we are rendering with Vray 5.
why not make it clear as day. Showing through tutorial as most are visual people, that this is what you need to generate a clean, non-noisy, high quality rendering video sequence for external/ Internal scenes.

[^Lele^]

Thank you Lele for the reply

I would have thought that if saving precalc officially is discouraged, which for a long time i always saved out, then why not chaos group remove it completely like the flythrough mode within LC and show the new Vray way and remove any confusion that the end user would have.

At the end of the day, chaos group are driving the way we are rendering with Vray 5.
why not make it clear as day. Showing through tutorial as most are visual people, that this is what you need to generate a clean, non-noisy, high quality rendering video sequence for external/ Internal scenes.

I hear you.
It's a delicate balance between progress (that of features, and the requirements they bring) and of compatibility and ease for long-time users (to not be eaten whole. ).
It's at least five years we're trying, with varied degrees of success.
In general, if you take a look at how we present Defauts (specifically the render setup ones) you'll know what we suggest.
I know it's sometimes a leap of faith ("per frame, for real? LC/BF? no way!"), and that sometimes it may look like it's rendering slower (than precalced IM/LC, f.e.), but the total time to final target (which includes the lack of settings fiddling and debugging) will be substantially lower.
If not, there's some bug, and we'd like to know about it.