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Monday 20 October 2014

Rendering - Which renderer is right for you?

Rendering software...


The other day, one of my students asked me if different 3D software rendered at varying speeds.
Although renderers can be integrated into the code of an editing program, they're often stand alone packages which run over a range of application. However whichever package you use they all fight the same key issues: features, speed and cost.
 
So to help you choose the renderer for you, I've created a list of current key software (it's not complete, especially if you also consider real-time/game engines, cloud based solutions or other novels rendering approaches which are beginning to come about  and depend less and less upon polygon counts...). i.e.:-

Mental-Ray/iRay -VRay - Corona - Octane - Maxwell -  Arion - Cloud Rendering - Fox Engine...
More details below, with links to their websites and a range of videos showing off some of their features... (I'll start with the Corona Renderer as it really dose have a very impressive video - watch all the way through and I think you might be impressed)

 

Corona Renderer
 - CPU interactive rendering...


 

VRay  

 
 
 

Mental Ray & iRay 

 
 
 
 

Octane 




 

Maxwell


 


 

Arion

 
 

Cloud Rendering

An interesting article from some time ago related to offloading rendering into the cloud, http://raytracey.blogspot.co.nz/
 
 

Game Engines..

This is only a taste of the detail which is now possible with real time game engines.
e.g. The FOX Engine realism

http://www.ripten.com/2013/03/21/fox-engine-created-joakim-mogren-would-crush-quantic-dreams-ps4-tech-demo/

 

Sunday 15 December 2013

Simulating Hair

Simulating Hair - more than a brush stroke...

It's a hard fact for computer game developers that not all CG characters are space-marines with a crew-cut [and there's a sentence I never thought I'd say]. Traditionally the computational heavy calculations needed to simulate hair have been the reserve of Hollywood (I'm reminded of 'Final Fantasy' and 'Monster Inc' both pushing the boundaries). Games have traditionally avoided dynamic hair, through crude polygon modelling, helmets, shaved heads or more ambitiously the layering of multiple hair textures with opacity maps. However with the arrival of 'Next-Gen' consoles the bar for 'realistic/dynamic' characters is being raised.

Tomb Raider: Definitive Edition for PS4, Xbox One
To illustrate this Tomb Raider has just been announced as being re-released for the PS4 and Xbox One. Very little has changed (including the hype). For example, Lara's head has been remodelled to add more detail and the media says the character is remade... In truth the largest graphical enhancement that is being used to promote the game is, believe it or not... Lara's dynamic hair.












Tomb Raider TressFX Hair
Although the revamped hair does indeed add to the sense of interaction, especially between Lara and her environment (showing how a good design has the environment as an extension of the character), it's not as new as the publishers would like us to believe. In fact the same tech was being highlighted (excuse the pun) back in march for PC development.














Simulating hair requires a number of considerations:
  • Visual look (E.G Styles, hair types, shine, wet, dry, shadow casting, self shadowing)
  • Dynamic movement (E.G. character movement, gravity)
  • Interaction with physical forces (collision detection, wind)
  • Artist friendly tools (E.G. virtual brushes and scissors, viewport rendering techniques, previews)
  • Render speed (E.G. hair strands numbers and controlling strands/tools, real-time vs pre-rendered)

http://www.hair-farm.com/
There are many aspects to creating virtual hair, and likewise there are a range of plugins/software which help 3D Artists to create them. Here is one of my favourites. Hair Farm - from 'Cem Yuksel'.


Deep Opacity Maps - Real-time hair shadows
Cem has been developing hair (and more - I highly recommend his youtube channel) simulations for some time now. Here's a video showing his efforts of creating shadowing and highlights, back in 2008.



Fast Simulation of Inextensible Hair and Fur
However, what use is a beautiful head of hair if 'we' can't render it quick enough... optimisation is always important.


NVIDIA Simulating Realistic Hair - Amazing Techdemo
Let's not forget 'the big boys' - E.G. NVIDIA showcase new characters and simulation with all their major hardware. Here are some of their simulations back in 2010 [btw Did you notice how NVIDIA's latest 'realistic' talking head was devoid of hair...]




Structure-Aware Hair Capture (Siggraph 2013)   -Dave's Highlight-
OK - Hopefully you've found this interesting and appreciate some of the complexity in simulating hair. To that end let me leave you with Dave's Highlight [something I'll try to include in each of my blog entries]. This vid' made me sit back and be quiet back in May 2013[yes it's that good].

Whatever the computer can simulate, IMHO it really is only half made if the artists are unable to utilise its features - i.e. Let's not forget the Artist Friendly Tools... this method of synthesizing hair shows great potential. It's one thing to make Lara's hair but if we're to recreate dynamic cities and virtual human interaction we need to speed up the process - and this might just the method to do it... 3D styled and dynamic hair, generated from a 2D image... astounding. Now, if we can take multiple photos around real people and automatically generate realistic hair... well, one step at a time. ;-)



Thanks for reading - do make sure you click on the links, there really are some great movies there.
Dave.

Friday 6 December 2013

New CG Simulations! (PS - I'm back)

Stimulating Simulating

Rumours have been circulating that this blog was dead... but just like a 'glitch' in 'The Matrix' I'm back ;-)

If there's one thing I like it's a good old fashioned / 'state of the art CG simulation'.
So here are four to entertain your eyes...

Tearing cloth (my favourite):
http://vimeo.com/80062633







Disney's snow (skip 1 minute in to see the snow in action):
http://www.youtube.com/watch?v=9H1gRQ6S7gg








Painting 2d 'ageing' using  -3d particles:
http://www.youtube.com/watch?v=wmEawPCAtEQ








Rock simulation:
http://vimeo.com/80383326







Although each simulation covers it own important discipline within CG, I've mentioned before about the complexity of creating believable Avatars [See my last blog entry on 'How to make a Virtual Character'].  I've chosen the cloth simulation as my favourite as clothing is an important part of nearly all characters and being able to recreate it is as important as a good skin shader [Here's another example which I mentioned back in my 2nd post : Realistic wool] This is particularly true when we consider the layering and complex interactions with clothing, which we take for granted in our 'real' day to day lives... until we have to recreate them virtually that is. ;-)

Dave

Sunday 21 October 2012

How to create a Virtual Character.

What makes a Virtual character 'Real'?

'Hideo Kojima', the Designer behind the 'Metal Gear Solid' games has sparked my interest this week and as it's been a while since my last blog I thought I'd turn this into a larger look at the challenges behind Virtual Characters.

Which Avatars have sparked your imagination - from Film to Science to Games - Use the comments section to let me know examples you can think of and why you think they stand out. :-)

Graphics
Often when asked what makes a virtual character Look real people talk of about graphics or animations. After all it's difficult to consider a character real when they're made of a few hundred polygons with boxed shaped heads. But now characters are can be so detailed that the Uncanny Valley is also mentioned. This  - where we might have a character look 'realistic' yet something doesn't feel right the 'illusion of life' can suddenly drop away (often leaving a very surreal mixed set of emotions with the viewer). Picture for example a character that could look real in still motion but suddenly feels very false when animated. Even a crooked smile can destroy the best of models.

Personally I feel Benjamin Button [VFX by Digital Domain : Directed by David Fincher in 2008] is still one of the best examples of a believable character. If you've not seen it I highly recommend the film. Here's a sneak peak behind the scenes into its effects.

But films can afford massive computations to create each frame - Real-time graphics have to be generated in around 1/30 of a second! Hence different techniques are used. Here's another of my favourites from the same year as Ben' Button [2008] showing Nvidia using multiple texture composites to create a real-time head [a method similar to modern games which use deferred rendering with multiple passes of screen renders]

Computer Games have also advanced with their animation - from marker based motion capture, to phosphor painted or videoed actor faces recording subtle skin movements, ie performance capture.

Here's a good example from 'Janimation' of human facial expression/animation being retargeted onto a CG character using marker based motion capture im 2011. Or take a look at the cutting edge performance capture tech' used behind the game L.A. Noire in 2010


Intelligence
Hold on a minute though. There is a key difference between film and other forms of avatars. It's one thing to watch a character that has been skillfully crafted and presented to us by a whole gaggle ['technical term' ;-)] of artists, but what happens if we can interact with it. The best looking virtual character will seems pretty dull if it responds to us like a 1970's robot.

One way to see how well a computer can mimic human behaviour is the Turing test. Essentially this is measured not by the avatars behaviour but our response to it. ie If 'we' can't tell that a computer is controlling it then it 'must' be behaving like a real person... Hmmm. Personally I don't like this test and find it quite flawed. Nevertheless it has been used many times.

It used to be said that a computer could never beat a Grandmaster at chess. This was because although it was relatively easy to program it to follow the rules of chess, to play at such a high level requires a deeper understanding of the human psyche. So it was quite a shock to many when IBM's
BigBlue defeated Gary Kasparov in May 1997.

I find it interesting to note that this 'test' was measured over a 'game' of chess... So perhaps it is not surprising to find that on the 27th September 2012 a computer games "bot" passed the Turing Test, as it hunted down and killed opponents in a video game was judged to have displayed behaviour that was indistinguishable from a human. Something many had said would be 'impossible'...

If we take this notion a little further we can see computer 'intelligence' [mimicking behaviour] spreading wider afield. For example this summer Google set a new landmark in the field of artificial intelligence with software that learnt how to recognise cats, people, and other things simply by watching YouTube videos . This takes us into the realms of 'learning behaviour' and neural networks... something I'll come back to another day I'm sure. What will it mean when search engines adopt 'intuitive behviour'?

Games are often the first adopters to new technology and being able to 'deliver' realistic and believable character to our living rooms has been a dream goal to many a developer. How though will this effect us - We may accept Tamagotchie's needing feeding, but how would we respond to a computer not wanting to play because it feels a little down..? ;-)
Microsoft have skirted around the concept of realistic avatars several times. In particular
'Project Natal' [June 2009] gave us a glimpse of what may be to come.

Character & Personality
The true beauty of this technology for me is that we are at last able to put to test the subject that philosophers have debated for 1000's of years. What makes us human and how do we define 'the person'. Modern culture refers to us as 'Mind, Body and Spirit'. Perhaps this is why Virtual Avatars are following the same path. ie Body = Graphics, Mind = Artificial Intelligence, and Spirit... hmmm this is a more tricky one.

If we are make a virtual character believable it not only must be visually detailed and 'perform' as if it has an 'awareness', it crucially needs one more thing. 'Spirit' - and how can we recreate that?
Well perhaps this can be represented by the traits which we associate with a persons character of personality. Do we care about the character enough to value their 'life'. This, imo, is the real challenge behind making a Virtual Character believable - sure we need the graphics, animations and A.I. (artificial intelligence), but can we go further? I say yes we can but it may not be quite the way we might imagine it to be. Just as with the Turing test, we may only need to mimic personality in order for us to believe in it. After all how many people name their cars and anthropomorphise them?

Video games have a unique angle upon the person who interacts with them. Not only the 'percieved freedom' but also the length of time a player will invest into a game; long enough to create an emotional bond or attachment to the characters they 'play' with. For me Video Games will take another leap forward when we truly care about the characters in them. Perhaps my favourite examples of this to date have been:-

GTA IV: Grand Theft Auto, a game more usually associated to violence and scale. Yet I would argue this scale/backdrop provides a depth that we need to relate to one another. And the huge range of interactions with the game mean the virtual world does not appear to be linear, as such the player allows themselves the subconscious freedom that 'autonomous' players are always going about their business. This is illustrated beautifully when in GTA IV the player is asked to kill another character, but they are given a choice. This is crucial as in that moment the ground is unclear - we have been taken away from a computers Ones and Zeros. If the player does not shoot, or does, the game [ie your character journey/'life'] will continue. There is no 'play again' option, instead there is a sense of forging ones destiny. You 'choose' your Fate. Simply gaming genius imo.

Heavy Rain: For me, this was one of the most beautiful games ever made. An example, similar in execution to GTA's but forced upon the player early on. Your character has two sons and you are out with them in a simple shopping mall. packed with people... Your son has a balloon and, as must be one of the most frightening nightmares for parents, you suddenly find that your child is missing. Fighting through the crowd, chasing after a balloon in the distance, the camera sweeps as you are buffeted between the shoppers... I found this to be genuinely heart racing - 'careing' about the safety of this vulnerable child. Again the player is given a situation - find your son or not... the game will continue either way. Consequences upon your actions but ALSO upon your emotional attachment to your virtual character. Would you feel guilt playing a character whilst also feeling/knowing that you were responsible for loosing their/your son?

Pushing this even further and returning to where I began. Hideo Kojima's talk was about Metal Gear and a particular character that he introduced, which had traits from a real person he knew in his life. He made this character behave in ways more 'real' than any other (for example, calling when you were busy and talking about their problems, rather then fixating upon yours). Curiously this was the character above all others which people/players rejected... It seemed that being real was not what people were after in an escapists world... I really recommend listening and reflecting upon this fascinating observation.

Conclusion
So what does this mean? Is there a point when 'real' becomes 'too real'? Do we desire 2 dimensional character in our virtual 3 dimensional worlds? Do we seek clarity in quality and avoid ambiguity?

I believe the answer is that, just as in real life,  we cannot separate the character from their context/surroundings. How often have you asked a persons 'how are you' simply out of politeness. We choose when to be intimate and share ourselves with others. In this was so too will our virtual characters of the future need to adapt their virtual behaviour to their surroundings. Then tomorrow's game designers will really have something to play with. Imagine fighting alongside your team mate only to find out their motivations are different to yours, or having to live with the remorse shown in other characters over 100 hours of game play, due to your actions. Consequence and Context will imo define tomorrows game play.

And Finally... what of the individual character. When they look and move as real as us, How will we judge them? To project personality upon a virtual character takes one more special trait imo. Integrity. A belief that the character will react in ways that mimic all forms of human emotion. Based upon their surroundings, history, personality and more. To create a truly believable virtual character will need lots of work, far more than an a SubSurfaceScattering rendering of skin. But just as movement can be synthesised (eg Natural Motion endorphin engine) so to will these other qualities...

It it my belief that the Uncanny Valley is only the beginnings of what we will experience with our virtual characters. hmmm perhaps I should create my own Turing test... one for the 21st Century and our virtual worlds. ;-)

---phew, that's a blog and a half--- If you're still with me, please share your thoughts/comments in the box below. Can you name any cool virtual characters? :-)

Tuesday 9 October 2012

Kinect on your wrist!

Microsoft have just made a mini Kinect that fits on your wrist to scan and record your hand/finger positions Pretty nifty if you ask me... To see their tech in action take a look at this video on the  'Microsofresearch' youtube channel

For me, Kinect is very cool tech'. Not only did it take a whole motion capture studio and placed it inside a box, but it's also cheap enough to be bundled with a games console... Sure, I know some will argue that it's not that accurate, but you know what - there are always those wanting to spread doubt.

This new device is why I find Kinect cool - not because of what it can do, but because of what it will do. Remember Kinect is still the first version (2nd if you count the PC version). There are other companies making similar devices - in fact, this tech is not new at all... but it's packaging and delivery to the mass market is a game changer on many levels.

In a couple of years it's likely that Kinect 2 will be out with improved accuracy, finger and face recognition. From this there will be all sorts of applications (and some social questions too - not least Health and Safety) - A revolution of sensor/positioning/gesture/scanning tech is about to happen imo and even more importantly this revolution will combine these multi-disciplines in to one single product.

From mapping our world through LIDER (Light Detection And Ranging) as I mentioned in my 'Mapping the Future blogpost on the 25th September 2012' to Disney's new Augmented Reality Cake patent (!) This can of worm's has only just been pierced. Some-one hand me a can opener! ;-)

Friday 5 October 2012

3D Printing - Who pays the postage?

For those of you who don't know '3D printing' is a magic process that makes something from nothing.

Ok ok, maybe there's a little more to it than that... Most stereolithography (to give 3D printing its proper name) builds a real tangible object, by solidifying a gel one thin layer upon another. If an object (real or virtual) can be sliced up, then 3D printing can put it back together... But, don't limit your thinking - check my links below and you'll see the sky is much higher.

I've noticed quite a surge of news about the topic recently so thought I'd put together a few news articles too. Before I list them though - I can remember a 'think tank' (hmm - I wonder if we could map/print thoughts one day?) saying that in 40 years printing objects will be as common as sending emails... well I don't know about that, but I do think if we said 40 years ago that we would communicate through emails and text we'd be seen as crazy. So you never know...

03-10-12 Printing Guns... Warning: Red Alert.

03-10-12 Printing toys and LEDs - Disney Attacks!
13-08-12 Don't want to wait for you model to be delivered - build your own printer!

02-08-12 Virtual Characters come alive - Print your own virtual avatar!

02-07-12 Feeling Low? Print with Sugar to make a new Liver (Onions still need to be bought)

06-04-12 Feeling Hungry - Print with Chocolate!
http://www.bbc.co.uk/news/technology-17623424 

So, what will this new printing age mean to us? Will we really be as keen at 3D Printing as we are with emailing? Perhaps cost will be a factor, or maybe acceptance? I find it curious that last week the BBC ran two stories on the subject and chose to use toys and guns? One thing is for sure. The costs are tumbling and there are even machines now that can print themselves - maybe the phrase 'parts and labour' will be replaced with 'Printing and Labour' - although I suspect the use of these machines will be more related to the materials they use rather than cost (what good is a washing machine part made of cheese - other than a tasty sandwich).

Imagine a car showroom where you design your dream car and as you sip a coffee it gets printed next door... 'sounds like science-fiction? We'll see...

Saturday 29 September 2012

Vimeo / Video anyone?

I thought you might like a video?

Whilst Youtube is the Internet Video Behemoth there are other video sharing sites out there - so here's a couple 'inspirational tech vids' that caught my eye recently, from Vimeo...

Giant Spiders - A 'cute' video projection method to give the illusion of real life giant spiders. I can't help but think how this would be if set up in a room with 100's of Spiders projected crawling out from the TV - sounds like a great game/art sequence to me [btw - If Capcom add this to future Resident Evil game remember where you heard it first ;-)]
https://vimeo.com/37176398#

Secondly a warning to us about out reliance upon computer tech'. Don't get me wrong - tech has so many applications, I'm not so much fearing what would happen if it was wiped out - For me it's more  a question of if we need to live our lives in a digital or analogue state? Can't we have both..? Anyway the vid's quite cool too. Enjoy!
https://vimeo.com/49425975