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monem
06-22-2009, 05:45 PM
dear friends ... many times i see an exterior or areal shot in a movie and it looks so real ... i wounder if they using GI in production to render it. did they really rendering with GI (with all its problems in flickering and long render time) or they depend on the manual lighting techniques and composting? and which school is better in both cases?

thanks all :)

McKronic
06-22-2009, 06:26 PM
I believe it is GI. Most films now use HDRI for the majority of the lighting and then enhance it with a few extra lights. A lot of studios have very optimized workflows for dealing with render intense things such as GI, fur/hair, etc...

phix314
06-22-2009, 08:28 PM
They've got the budget for many many processors... no "long" render times there. ;)

RagingBull
06-22-2009, 09:11 PM
Big places with the money...most probably but wouldn't count on it.
I'd say a lot of it was done in the more traditional way.
Also don't forget you can still use HDRI's without having to resort to GI, and still get that 'GI' look without massive render times and 0 flickering.

monem
06-22-2009, 11:48 PM
i am always hear that we can achieve the GI look without using real GI but i do not know how it can be done right. i did some trials but i think it is not right. so how it can be done? i know it include a lot of composting work with passes but i do not know which passes should i work with. and i have another question: what is the different between GI and ambient occlusion? is it a "fake" version of it? or we should use both?

phix314
06-22-2009, 11:58 PM
GI is global illumination. Bouncing virtual photons around the scene. AOcc is a dirtmap, geometry closer together darkens. I've seen ways using AOcc to mimic some GI effects, but by no means is it a sub.

mr Bob
06-23-2009, 07:54 AM
On T4 I used a combination of HDR , Ambient Occlusion , Reflection Occlusion. Splitting out some 35 odd passes. Full Gi would take far to long to turn round changes.

b

Wizdoc
06-23-2009, 10:17 AM
Many of the environment shots in films (and TV shows, commercials etc.) are not rendered as such, but a lot of them use matte painting with camera projections. You can really push those techniques quite far these days without having to resort to "brute force" the shot.

It's easier and faster to establish the look of the shot that way as well. And there's zero flicker and artifacting.

playmesumch00ns
06-23-2009, 12:31 PM
HDRIBL + point-based colour bleeding gets you most of the way. And phix314, when you're rendering an entire photoreal city, even the biggest render farm starts to look too small.

ndeboar
06-23-2009, 04:46 PM
Point based color bleeding is the bomb. For me it's the fastest most reliable GI solution for film.

Although I spent a week at a place that works with V-Ray and they where using full GI on everything, their average render time was 2 hours per frame. But man, its looked sweet.

monem
06-23-2009, 08:44 PM
so friends is there any explanation or tutorial for HDRIBL + point-based colour bleeding method? i mean what is the scenario if i want to use this method?

ndeboar
06-24-2009, 09:50 AM
It's only really supported by renderman render-ers (eg prMan, 3Delight, Pixie). The docs that come with those renders have good tutes on settting it up. Renderman for maya 3.0 has point based color bleeding im pretty sure.

playmesumch00ns
06-24-2009, 03:02 PM
I think the later versions of mental ray support it as well.

ndeboar
06-24-2009, 03:04 PM
Think mental ray has color bleeding support, but it's ray traced, not point based.

monem
06-25-2009, 12:32 AM
i am using Vray ... is there anyway to do so with it? is there anyother technique? i do not know if render man work with max or not.

mister3d
06-25-2009, 12:41 AM
I heard about color bleeding in AO both in vray and mental ray, but I don't use AO so I'm not sure where it is. Mental ray has a color bleeding simulation in ah!design shader in "fg+hilights only" mode, which works with FG only, and this makes it not so complelling to me...

lazzhar
06-25-2009, 06:49 AM
If you are asking about the GI look that we see in those Vray(or similar) interiors, i can say surely that it's impossible to get the same result whatever you do trying to fake it.
So it all depends on the shot. If it's a character running on a sand in a sunny day, then yes you can get similar result to GI without using it.

mister3d
06-25-2009, 01:13 PM
If you are asking about the GI look that we see in those Vray(or similar) interiors, i can say surely that it's impossible to get the same result whatever you do trying to fake it.
So it all depends on the shot. If it's a character running on a sand in a sunny day, then yes you can get similar result to GI without using it.

Impossible for animation? I think if you first render with gi and then use it as a reference, you can get quite close.
Your example with a desert is quite good, for example you can attach a light behind the sand for a bounce light.

lazzhar
06-25-2009, 01:28 PM
Impossible for animation? I think if you first render with gi and then use it as a reference, you can get quite close.
Y
Sure, but don't forget that a great part of the GIish look in interiors is coming from the very soft raytraced shadows plus glossy reflections. I don't think one could get any closer to the sharp solution people are getting with vray specifically.

mister3d
06-25-2009, 04:50 PM
Sure, but don't forget that a great part of the GIish look in interiors is coming from the very soft raytraced shadows plus glossy reflections. I don't think one could get any closer to the sharp solution people are getting with vray specifically.

Vray doesn't work very fast with shadowmaps, so it makes sense to use soft vray shadows for bounced light, so with vray ou can achieve pretty natural-looking fake bounced light with many area lights. Mental ray works faster both with soft and shadowmaps, from my experience. But you can also bake lighting into the environment and use bounced fake light for character.

lazzhar
06-25-2009, 05:47 PM
Mental ray works faster both with soft and shadowmaps..

Are you sure MR raytraced area lights are faster? I don't use Vray but in my experience in mr for maya one needs to crank up the samples a lot to get any decent grain-less result and it affects dramaticly the rendering time. I just played with vray beta for a while and it looked a lot faster and smoother.

mister3d
06-25-2009, 06:18 PM
Are you sure MR raytraced area lights are faster? I don't use Vray but in my experience in mr for maya one needs to crank up the samples a lot to get any decent grain-less result and it affects dramaticly the rendering time. I just played with vray beta for a while and it looked a lot faster and smoother.

Hmm... this is my test. In vray I also set shadow samples priority (instead of global sampler to solve it all), which cut render time in half, but still mental ray was far ahead. If you want, I can give you test files for both renderers. I judged by noise level, and vray shadowmaps were almost the same time as mental ray soft shadows.

http://img294.imageshack.us/img294/3345/softshadowsv.jpg (http://img294.imageshack.us/i/softshadowsv.jpg/)

lazzhar
06-25-2009, 07:00 PM
Hmm... this is my test. In vray I also set shadow samples priority (instead of global sampler to solve it all), which cut render time in half, but still mental ray was far ahead. If you want, I can give you test files for both renderers. I judged by noise level, and vray shadowmaps were almost the same time as mental ray soft shadows.



I suppose you're using Max right? Unfortunately I don't and have no access to vray for maya to run a test now.

monem
06-25-2009, 09:00 PM
guys i watched some DVD from gnomon called "digital sets in maya" and the guys did not use any GI solutions ... just AO + HDR lighting + direct light . and he achieved a very good result so i think u should see it.

B4C
06-26-2009, 06:45 AM
I've heard of people using GI with IBL. Isn't that overkill since the probe has bounce light info?

RagingBull
06-26-2009, 01:07 PM
i can say surely that it's impossible to get the same result whatever you do trying to fake it.

Such a ridiculous statement buddy, so I'm not going to instigate an argument over it but I can definitely say, hand on heart you can get at least 90% of the way AND have more control. Then it's just down to post production tricks to finish off the illusion of realistic lighting or whatever look someone wanted.
A huge help is having the HDR's for the ambient light information, and even without that you can still sling your own rig together, use an image background for light positions and colours to get a fairly good solution. (but there are lots of scrips that can automate that as well)

guys i watched some DVD from gnomon called "digital sets in maya" and the guys did not use any GI solutions ... just AO + HDR lighting + direct light . and he achieved a very good result so i think u should see it.

Yep, some good information on their DVDs, and it really doesn't matter what software you are using as long as you can do the fundamentals of what they are showing you.

This is a very good one to get as well:
http://gnomonology.com/group/16

And Jeremy Vickery's tutorials are fantastic as well (the masterclass was awesome).
http://www.thegnomonworkshop.com/store/product/185/Practical-Light-and-Color

I'd personally say that GI is REALLY useful for getting a quick idea of what a scene should or could look like, as long as you keep settings low to blast out a render. It can chuck up soo many problems if your work is animated that I'd rather just leave it alone unless working on a still.

Lastly, the colour bleed stuff... isn't that just a diffuse reflection anyway ?
(but good to have some tricks if it saves render time)


:thumbsup:

lazzhar
06-26-2009, 03:36 PM
Such a ridiculous statement buddy, so I'm not going to instigate an argument over it but I can definitely say, hand on heart you can get at least 90% of the way AND have more control. Then it's just down to post production tricks to finish off the illusion of realistic lighting or whatever look someone wanted.
A huge help is having the HDR's for the ambient light information, and even without that you can still sling your own rig together, use an image background for light positions and colours to get a fairly good solution. (but there are lots of scrips that can automate that as well)


Rendering interiors like rooms and kitchens as good as what people are doing in arch-viz? Without using raytraced arealights and glossy reflections? Sorry but Nevaaaaaah http://forums.cgsociety.org/images/icons/icon10.gif

ps: lighting with HDR is a GI as well.

playmesumch00ns
06-26-2009, 04:58 PM
You absolutely, positively cannot fake GI. Yes you can get plenty of the same 'feel' with cheaper tricks, but 90% of the way there just doesn't cut it buddy. Getting 90% is the easy part, getting that last 10% is what makes the difference between good vfx and outstanding vfx.

An environment map does not 'contain bounce information'. It's a measure of the light arriving at a small part of the world from every direction. If properly shot, it's an absolutely essential tool for integrating an object into a scene.

What happens after the light from the environment arrives at that object though is a very different story. Without a good representation of diffuse, glossy and specular light bounces between surfaces of your CG objects they will never look totally real.

monem
06-26-2009, 05:42 PM
good openions here :) a friend of mine told me about a way to deal with GI effectivly i do not know if it fits or not. it is about using "render to texture". so u can store all the lighting information with the texture. but this is for the static objects only. and another render pass for the animated object and then composite. i think this is will solve the flicker problem and the long render time. what u think guys?

playmesumch00ns
06-27-2009, 02:25 PM
Yes, 'baking' as it's commonly called is a very good solution for speeding up your final renders.

mister3d
06-27-2009, 09:23 PM
good openions here :) a friend of mine told me about a way to deal with GI effectivly i do not know if it fits or not. it is about using "render to texture". so u can store all the lighting information with the texture. but this is for the static objects only. and another render pass for the animated object and then composite. i think this is will solve the flicker problem and the long render time. what u think guys?

There are two ways: one is render to texture, and another is a static GI, which is a point-cloud data of photons. The last one is preferrable as it's faster to make.

RagingBull
07-10-2009, 01:20 AM
Rendering interiors like rooms and kitchens as good as what people are doing in arch-viz? Without using raytraced arealights and glossy reflections? Sorry but Nevaaaaaah http://forums.cgsociety.org/images/icons/icon10.gif


Oky doky, that's fine if you don't think it's as pleasing to look at but you surely cannot deny that a huge amount of CG in film isn't GI/FG ?
As the original chappie said:
'many times i see an exterior or areal shot in a movie and it looks so real'
(not talking arch-viz per se)

Dont forget the one of the strongest reasons to be rendering out in layers is so that individual parts can be altered in compositing (ala - glossy reflections etc). It's not just to make more work for the compy's :D <---why does that 'smiley' look like it's got constipation?

ps: lighting with HDR is a GI as well.

Only if you use it they way YOU are talking about, it can be used in different ways mate, and those ways aren't using GI solutions.
Check out the various links below, and you'll understand:
http://www.hdrlabs.com (loads of other info here but primarily for the use of Picturenaut & the HDR Shop plug in 'diffuse_sh.exe' but their sIBL stuff is fantastic)
http://www.xsi-blog.com/archives/248
http://immerg.com/index.php?option=com_content&task=view&id=346&Itemid=44 (essentially a video demonstrating what Harry said in his blog)
http://gl.ict.usc.edu/Research/MedianCut/
http://www.binaryalchemy.de/develop/lightdome/index.htm - many other plugins/programs offer a similar result to generate 'standard' lights from the image in your chosen 3d app.


You absolutely, positively cannot fake GI. Yes you can get plenty of the same 'feel' with cheaper tricks, but 90% of the way there just doesn't cut it buddy. Getting 90% is the easy part, getting that last 10% is what makes the difference between good vfx and outstanding vfx.


Right, and we are saying the same thing I think (I didn't elaborate as you did).


you can get at least 90% of the way AND have more control. Then it's just down to post production tricks to finish off the illusion of realistic lighting or whatever look someone wanted.

And when I say 'control' I'm merely just talking about subtle changes to lighting that would typically cause drastic changes in a GI/FG/Vray type of rendering solution (adding extra lights for a character or something).
And exactly as you said playmesumch00ns, it's the last 10% (irrelevant percentage anyone thinking, why 10%? :D ), usually subtle tricks/techniques/fx - whatever you like to label it as...they are the parts as you rightly said that gives you the grin on the face when you've done it, or even seen something at the cinema! (and you wished you'd done it!)

:beer:

playmesumch00ns
07-10-2009, 10:17 AM
The point I was trying to make was that GI (and here I'm talking about global illumination, as in indirect reflections, not mental ray's or any other renderer's particularly implementation) is what gives you that last touch of realism that is *impossible* to get any other way. Yes the 10% is kind of an arbitrary number, but it fits with experience.

And I think you'd be surprised how much GI, or indirect diffuse solutions in particular, is used in production (especially since prman 12.5). I know we do, ILM certainly do, SPI are now raytracing everything, I'd be very surprised if the other top-end facilities weren't doing so too.

mister3d
07-10-2009, 01:20 PM
And I think you'd be surprised how much GI, or indirect diffuse solutions in particular, is used in production (especially since prman 12.5). I know we do, ILM certainly do, SPI are now raytracing everything, I'd be very surprised if the other top-end facilities weren't doing so too.

So GI is already there, in big production?

RagingBull
07-10-2009, 01:36 PM
It's really good chatting about this kind of stuff, and if you are using 3d at your place of employment I guess it's going to change from studio to studio but that's a given.
It's good having threads like these which pass on 'real world' experience's, a LOT to learn !

...I think you'd be surprised how much GI, or indirect diffuse solutions in particular, is used in production (especially since prman 12.5)... I'd be very surprised if the other top-end facilities weren't doing so too.

PRman is alien to me at the moment, although a possibility to begin learning for the online (refresher) courses I've signed up to, I don't know how widespread it is (esp in town?).
Could you elaborate on 'indirect diffuse solutions' ? sound's nifty !
:cool:

playmesumch00ns
07-10-2009, 05:36 PM
PRMan's point-based indirect diffuse solution is the nuts:
http://graphics.pixar.com/library/PointBasedColorBleeding/index.html

You can keep your final gathering crap, fast, flicker-free GI is where it's at :)

Per asked me the other day what projects we've used it on - the answer's pretty much everything since it came out. That includes the last Narnia (GI on fur, sweeeet), Sweeny Todd, Watchmen, Potters 5 & 6, Night at the Museum 2 and everything we have in production at the moment.

RagingBull - PRMan is pretty much the de-facto standard for film vfx rendering. Indirect diffuse just means diffuse reflections of light between surfaces, as opposed to glossy or specular reflections, which we typically compute via raytracing, although the point-based stuff can do glossy reflection too with a bit of manipulation.

mister3d
07-10-2009, 07:33 PM
That's interesting... I was wondering if Prman is suitable only for large groups of experts to use, whether this holds true till today too? For example mental ray is quite possible to use for a single person or a small group, but Pman takes a lot of time to setup?

RagingBull
07-28-2009, 08:05 PM
PRMan's point-based indirect diffuse solution is the nuts:
http://graphics.pixar.com/library/PointBasedColorBleeding/index.html

You can keep your final gathering crap, fast, flicker-free GI is where it's at :)

Per asked me the other day what projects we've used it on - the answer's pretty much everything since it came out. That includes the last Narnia (GI on fur, sweeeet), Sweeny Todd, Watchmen, Potters 5 & 6, Night at the Museum 2 and everything we have in production at the moment.

RagingBull - PRMan is pretty much the de-facto standard for film vfx rendering. Indirect diffuse just means diffuse reflections of light between surfaces, as opposed to glossy or specular reflections, which we typically compute via raytracing, although the point-based stuff can do glossy reflection too with a bit of manipulation.


Cheers for the insights man !
Will buy you a pint if I bump into you in Soho !
(i presume you have black hair, very red skin and pointy teeth ? :)
:thumbsup:

mercuito
08-01-2009, 01:38 AM
Can I pose a question?

I see talk in the earlier posts about using HDR lighting without GI. What exactly is meant by that? Are you talking about using something like a prefiltered enviroment/spherical harmonic soultion, or is there something simpler I'm missing here?

Is that for the ambient portion of the lighting or for direct lighting?


Thanks in advance for any insight on this.

jeremybirn
08-01-2009, 02:42 AM
I see talk in the earlier posts about using HDR lighting without GI. What exactly is meant by that? Are you talking about using something like a prefiltered enviroment/spherical harmonic soultion, or is there something simpler I'm missing here?

A lot of movies make extensive use of IBL for fill light in the outdoor scenes, but don't use any GI. An IBL dome can be just another source of direct illumination, just like an area light. (Like an area light that's big and curved and multi-colored, but still a direct light source not requiring any bounces.)

-jeremy

mercuito
08-01-2009, 07:14 AM
Thanks Jeremy. Is that a option in Maya/mental Ray? I don't recall seeing that as a option on the ibl node...

Tora_2097
08-01-2009, 10:31 AM
good thread.

Coming from the architectural viz field I can say that in we for sure use full GI (Irrmap+LC in Vray) for all stills and 90% of our animations. I say 90% because you`ll be drowning in pool of problems once your objects/ lights start to move. You could use brute force/ montecarlo solutions but they mostly take to long to render so in these cases we are lighting the shots traditionally with a GI reference frame and a set of approximating direct/bounce lights for the animation.
With regard to an earlier post I can say that in my opinion Vray raytraced area lights need just as long to render as in mental ray without any clear winner. If you check the rawlighting pass in vray after the rendering you might notice that in fact your light has been still quite noisy Vray does only one heck of a job to hide this with its soft GI'ish appearance- typically called "the vray look" :)

When I am working on character projects I try to avoid traditional GI (FG, Photonmapping, Irradiance mapping etc ) like the plague and use an IBL pass + directional + bounce + AO (raytraced). That being in Mental Ray. MR does point based AO out of the box now, I am confident it could be modified to do point based color bleeding as well.

@ mister3D: I have not used Prman but 3delight instead until today and I would say that speaking just of the engine itself MR is surely vastly more complex to handle. Mastering renderman does not in the first instance mean to learn to use an engine but much more to learn the language/ concept behind it. Even if you do not want to dive into the shading language and just want to use lets say prman integrated in maya or 3delight in XSI you could do so with a lot less knobs and sliders than Mental Ray.

@ playmesomech00ns: How badly does in your experience the deployment of raytracing inside of prman hurt the overall performance? Especially in junction with displacement mapping ? I am using 3delight and find the speed penalty rather severe- if you compare it to Mental Ray that is. An interpolated (non-raytraced technique) is much needed imho. The method described here (http://graphics.pixar.com/library/SoftReflections/paper.pdf)sounds rather fancifull and might not even work in all cases- which should not imply that it is badly done of course. :)


regards,

Benjamin

jeremybirn
08-01-2009, 01:15 PM
Thanks Jeremy. Is that a option in Maya/mental Ray?
Yes. Perhaps it's not a great option, but it exists. If the IBL node has "Emit Light" checked it works as a direct light source. You don't need FG or GI turned on to use it.

Once you adjust it to look good, this can be surprisingly slow to render in MR. If you're going to use lower quality settings you might scale-down a complex HDRI map first. (You could also try it without Raytracing, without the raytraced shadows it could still work as an ambient pass.)

-jeremy

mister3d
08-01-2009, 02:08 PM
we are lighting the shots traditionally with a GI reference frame and a set of approximating direct/bounce lights for the animation.

Why not to bake in the GI and use :bounce: lights for characters?


With regard to an earlier post I can say that in my opinion Vray raytraced area lights need just as long to render as in mental ray without any clear winner. If you check the rawlighting pass in vray after the rendering you might notice that in fact your light has been still quite noisy Vray does only one heck of a job to hide this with its soft GI'ish appearance- typically called "the vray look" :)

I will not make a claim that vray is slower because I didn't finish all the tests. And some variables yet need to be considered like bsp tree optimising. But for now I would say mr is faster for aminations in some instances.

MR does point based AO out of the box now, I am confident it could be modified to do point based color bleeding as well.

What? where, where is it? :love:


@ mister3D: I have not used Prman but 3delight instead until today and I would say that speaking just of the engine itself MR is surely vastly more complex to handle. Mastering renderman does not in the first instance mean to learn to use an engine but much more to learn the language/ concept behind it. Even if you do not want to dive into the shading language and just want to use lets say prman integrated in maya or 3delight in XSI you could do so with a lot less knobs and sliders than Mental Ray.

Maybe I will learn maya with time... untill then I can't even touch renderman... thank you for the info, I will keep that in mind.
By the way, what a wonderful gallery on your website, one of the best archviz I'vs seen ever.

playmesumch00ns
08-02-2009, 06:04 PM
@ playmesomech00ns: How badly does in your experience the deployment of raytracing inside of prman hurt the overall performance? Especially in junction with displacement mapping ? I am using 3delight and find the speed penalty rather severe- if you compare it to Mental Ray that is. An interpolated (non-raytraced technique) is much needed imho. The method described here (http://graphics.pixar.com/library/SoftReflections/paper.pdf)sounds rather fancifull and might not even work in all cases- which should not imply that it is badly done of course. :)

PRMan's raytracing implementation isn't that bad really, when you think about what it's doing (tracing a against a multiresolution set of hundreds of millions of polygons). You just have to be very careful how you use it. We almost never trace against displaced geometry, and almost never trace against motion-blurred geometry.

The thing that's really slow in prman is shading the ray hits, rather than finding them. That's why the technique in the paper you link to is quite common in our pipeline - we've been doing something similar since the cryptex shot on The Da Vinci Code

mister3d
08-07-2009, 12:47 AM
Have you seen this? http://area.autodesk.com/inhouse/videos/siggraph_2009_autodesk_design_visualization_part3

Looks promising, especially as they claim to increase the consumer card speed by 12x next year.

playmesumch00ns
08-07-2009, 12:28 PM
It's interesting, but they still haven't shown anything that can't be done in an optimized cpu renderer. Until they actually show some pretty pictures generated with it rather than the god-awful programmer art they've been showing so far, I'll reserve judgement.

mister3d
08-10-2009, 08:02 AM
http://www.cgarchitect.com/news/SIGGRAPH-2009-CHAOS-GROUP-GPU.shtml

ice-boy
08-16-2009, 07:08 PM
pixar graphics has a new .pdf file on point based color bleeding.
http://graphics.pixar.com/library/PointBasedColorBleeding/SlidesFromAnnecy09.pdf

ice-boy
10-07-2009, 04:17 PM
point based color bleeding was used on some fur and hair. does anyone have any links or papers on this? for hair and fur? i dont understand how point based color bleeding works on thin hair.


thanks

playmesumch00ns
10-08-2009, 10:27 AM
What part don't you understand?

ice-boy
10-08-2009, 10:33 AM
i dont understand how you can make a point cloud from a thin hair line or fur. isnt it to small?

ndeboar
10-08-2009, 11:44 AM
Point based occlusion and color bleeding work fine on fur.

playmesumch00ns
10-08-2009, 02:39 PM
i dont understand how you can make a point cloud from a thin hair line or fur. isnt it to small?

Smaller than an infinitesimal point?

mister3d
10-08-2009, 03:25 PM
Smaller than an infinitesimal point?
hahaha, nice! A point doesn't have any mass in maths, but it must have a definite precision.

ice-boy
10-11-2009, 07:25 PM
Smaller than an infinitesimal point?he he :)

any pics for fur and hair like this?
http://img104.imageshack.us/img104/3893/point1.jpg (http://img104.imageshack.us/i/point1.jpg/)
http://img67.imageshack.us/img67/8805/point2.jpg (http://img67.imageshack.us/i/point2.jpg/)

ndeboar
10-11-2009, 08:16 PM
These are just renders of point clouds, not the same thing as point based occlusion/color bleeding.

Here is an example of point based color bleeding on fur (stolen from the pixar forum, https://renderman.pixar.com/forum/showthread.php?s=&threadid=9327&perpage=25&highlight=fur%20point&pagenumber=2)

http://forums.cgsociety.org/attachment.php?attachmentid=147182&stc=1

julienTD
10-15-2009, 10:07 PM
hehe, fun to see my fur ball render here !

As experience point based is the future of almost everything for global illumination in production. We use point based for all the IBL ,color bleeding, occlusion and rough reflection in our production pipeline and it's very efficient, amazingly fast and especially with big scene, but the most impressive thing from the point based is the memory foot print you raise during a render, you can render a big scene with millions polygons and hair , 8k texture maps or bigger with 4gb of ram only, this is only possible with renderman and point based. Now in rps 15 point based is realy accurate (really close to raytrace) but 6 to 15 time faster even for GI in hair. ( a point cloud can store everytype of geometry including hair and even volumetric, because now in prman 15 you can render GI and occlusion in volumetric, and it's really efficient). Point cloud are also really cool to include all the displacement so you can do displacement occlusion on detailled mesh, rough reflection, refraction, occlusion reflection and even area object lighting in no time. We are not using raytrace anymore on our production even for soft shadow map.
For sure sometimes people prefer the look of a real raytracer for GI but with some tweak and experience point based is the production ready solution for almost everything, simply because of the speed and the quality ( no flick in animation).

All big company use point based for GI now, look ILM on transformers, iron man, imageworks on G force and pixar on UP and many many more others good result example.

jd.

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