Lightmap for Animation (comparison?)

[travistlo]

I was wondering if anyone has tried this yet:

Using a high quality lightmap for a walkthru?

If i understand it correctly, The lightmap will be calculated once for the entire scene. If you use high enough settings(LM for 1st & 2nd), can you render out the lightmap faster than the irr. map (using incremental) with equal quality?

I may have to try it on a small scene. Unless someone else has.

travis

[paulison]

that would be awesome but i dont think the lightmap works to well by itself?

if you have any luck let us know! *remembers the olden days*

[natty]

hi guy's

this was a quick test i did with light map first bounce and Quasi in second ...... quality was pretty good and the render times are very fast ... but it is a very simple scene .... http://render-time.com/vray/lightmap.wmv

[percydaman]

nice! as daelf would say, "looks nice, now lets see your settings."

[travistlo]

I am going to try to comapre using that teapot scene, that people have been playing with in the Maxweel thread. Going to try to use most of different materials vray has to offer..with the exception off SS.

Well see how it does.


How long did the LM take to compute natty?

[natty]

the lightmap took 15 mins .. @ 1800 subdivs

[travistlo]

Id be willing to bet that would be faster than incremental irr. map, but the QMC might slow done the raytrace rendering part. Well see.

[pengo]

is it lightmap useful for exterior view too?

can it be used for this kind of scenes?

thanks in advance

[cocolas]

I've used it for exteriors and it works well as it does for interiors...


paul.

[pengo]

thx


I hope for the next future to use it

[tammo]

i tried lightmap (secondary engine) for an animated walktrough.
the model was a moderately complex building.
the camera moved into the building and through a very large room (bank).

the quality was very bad even with a large lightmap file (250 mb).
settings tried: flythrough, world scale, several filter settings, sample settings.
qmc for secondary was faster and looked better.

seems to be usable only for simple scenes with low poly count.

edit: my animation was over 1000 frames long, maybe that has something to do with low quality?

[paulison]

hey Tammo,

What QMC settings do you use for secondary bounces in animations? currently im using 6-3

Lets say for an animation at 720x576, what GI settings would you have? at the moment im using -3 -1 with 70hsubs, 2 interp

Also, for AA, i've been using fixed 1 - 4 as is seems much faster than adaptive for large detailed scenes

thanks,
Paul

[vlado]

my animation was over 1000 frames long, maybe that has something to do with low quality?

You will need more subdivs for the lightmap for long animations, especially if the camera path covers many different parts of the scene. The subdivs are spread out across the entire animation, so you will need to increase them accordingly.

Best regards,
Vlado

[DanielBrew]

Vlado (or anyone who knows about lightmaps),

Sorry I'm confused now.

How would you calculate a lightmap for an flythro of say 1000 frames where only the camera moves? Would you use the same method as you would for calulating an irradiance map (by setting lightmap mode to flythro and rendering every 10th frame and auto saving the result) or is there a better way?

Thanks

Dan

[Gijs]

Dan,

Flythrough is an optional mode for lightmap, where it calculates the lightmap for the whole animation in one go. In the viewport it apears as seeing all frames blended together in one frame. But like Vlado mentioned, when your camera sees a lot of the scene during the animation, you would need many many more samples than for a still image. I have tried to render with lightmap only for an animation, but without good results so far. The outcome is always blotchy even with very large lightmap files. Lightmap +QMC is a great couple though.