I've been trying to understand gestures for a while now. What's a gesture... weeeell, in a way you could call a pose a gesture. Such as in gesture-drawing, it's only one drawing as a gesture, as an idea, you're trying to capture the essence of that gesture in one pose. But what I'm more interested at the moment is gestures as small bits of action that give detail to an animation. You could also see pose to pose animation as gesture to gesture animation, because it can very well be that, in fact. When I was animating Cousteau a year ago I used to try to simplify his animation and have round, simple movement that doesn't 'bounce' much, I was obsessed with the idea of using soft accents mostly, meaning... instead of hitting hard accents, just keep the movement going forward, and not 'bounce'. The result was lacking real detail though, and I was disappointed. I already wrote some on this lovely matter... here. After a while I realized, in my infinite wisdom (hehehe), that in fact I shouldn't try so hard to remove hard accents from my animation, and I should focus more on the details, and keep a balance of soft versus hard accents, simple vs complicated, etc, based on the context. Which is hard, of course, and I have 100 more years to learn about that, and after 100 years I will know everything. :D Yeah. I still think there is a strange beauty in simple animation with mostly soft accents, and I want to get to know more about that style... while not being so careless with gestures and details.

Anyway, a gesture can be a small elbow movement, or finger movement, or a shoulder hunch... for example, the head usually does a lot of things, animating the head on a simple path with very clean animation that lacks detail, I think in most cases will look lifeless. But add gestures to that movement and all of a sudden it could become alive! I think we can see these gestures as small and large, or maybe small, medium and large... large gestures should probably be planned more carefully and described with extremes and breakdowns, in pose to pose animation, because a large gesture can very well affect the entire body. In fact, I think most gestures affect, even if very subtly, more or less, the entire body. You may think a smaller head gesture might not affect the legs, but I'd say... it often does. Because it's not just a head gesture, it's a... gesture. So it starts with the head... it has a very visible effect on the chest, but it might also subtly affect the hips and limbs. Depends, if it's a really small and especially slow gesture, it can have a smaller area of influence. Small gestures could be added as a layer of detail on top of an initial, cleaner, simpler animation. So... the difficulty is to keep the base animation layer clean, and free of unwanted accents, or jerks. And then add those accents where they're needed. I used to be so afraid of accents... because if they occur at the wrong time and place, the seriously mess up things. But it took me a while to realize that, in fact, accents are good, and necessary, just... when they're placed right, when they're motivated and correct/accurate. Also, it's easy to control the larger ones, but hard to control the subtle accents. Because any contrast, even a small one, will create an accent.

For example, if you animate a stretch, and only try to capture that movement through posing , good timing, and clean paths of action... it will probably lack the tension that would add believability to the stretch. Add some subtle jerkiness where it's needed, where the tension should be, and wow!

I think I should write a post about tension vs relaxation... this is another something I've started thinking about fairly recently.

 
DEMO REEL 2007 03/06/2009
 

Just cut a second version of my demo reel - I just had to add my Wolfy... Click below and watch in hi rez (42 MB):

or low rez (9MB):

 
 

More or less finished, but the truth is that I didn't refine the animation that much and I shouldn't call it finished yet... But as unfinished as this shot is, it's better than other things I've worked on before... or so I think. I think I'm learning some stuff here, but I also hit another wall - I found myself not being able to refine my animation any further, because I really don't know if what I'm correcting is OK or if I'm only making things worse. This animation thing is really tricky business - I guess I need to understand more about it before being able to go any further. I'm not a fan of working like a locomotive... I think that people who really know what they're doing are successful, while... say... beginners... work hard and with unfortunate results. There's so much polished animation that has really been... polished a lot, I presume, and it still looks awkward, because the animator had an incomplete understanding of what s/he was.... animating... maybe from an acting point of view, or maybe incorrect mechanics (yeah, it's fun and easy to animate shapes, but without understanding the mechanics of motion the results are artificial), or just wrong planning. It's so easy to get carried away by an idea or by some graphical concept, and forget that we're in fact dealing with acting and body mechanics and things that are supposed to be functional, not just cute and graphical.

But yeah, appeal is important too - this is an area I know too little about, and it shows. Comparing my animation to that of others I think mine is less cute... less appealing maybe, I didn't try that hard to make cartoony animation and exaggerated expressions. I tried to go for more realistic reactions or gestures, which is stuff that I find most interesting to animate, and to watch - but hard to do. A cartoon take is a hell lot easier, but I don't like cartoon takes, and I think it's stupid and annoying that people use them aggressively in animation as a replacement for acting. I'm learning about gestures now (I'll post some stuff about gestures soon), and there's so much depth and richness in this microscopical world of the small gestures people make... this is the real beauty. But I'm not good enough just yet, to be able to animate them right... Anyway, more about gestures later, cuz this is awesome stuff!!

When I was animating Cousteau I was trying to get simple smooth movement with very few bounces in there, and most accents be soft - the result was not necessarily soft, but it sure was... somehow... low rez... like an image that doesn't have detail. And at that time I didn't know what was missing and why some people told me that my animation is floaty - I mean, I knew what I was doing, to a point, and I was trying to keep the timing alive, but then I didn't know how to fill those large simple spaces... Lots of animators do moving holds and snappy jumps from one pose to another, and so they jump over the transitions quickly and kill the details - the Spline Doctors I think, in a podcast, they admitted that when they were fresh out of school, they could set a pose, and then another, and another... but what exactly was supposed to happen between those poses they had no idea! Now with me... I guess what happens is... I also have a fairly loose idea, if any, but instead of doing pose jump pose jump etc, I'm actually trying to animate that movement between poses. And because I'm a beginner, the results are... less accurate... :D So now I've started analyzing more video and I hope I'll start understanding more about that space in between poses. To conclude this thing - there's an expression among animators: tight timing. Get tighter timing in there!! Ammm... tight timing is cool, and I suppose people mean "timing with a wider dynamic range obtained by exaggerating it - fast actions become faster and slow movement becomes a subtle moving hold". Well, it can look great when it's done masterfully, like they do it at Pixar, but on the other hand, this is exactly the stuff that can also lead to replacing detail with something that... exaggerated a little bit more... is nothing else but pose - jump - pose - jump... (I guess 'tight timing' could also mean - timing that is more accurate... just like "pushing a pose" can mean exaggerating it, but also making it more accurate - 2 different uses... I prefer the second; in the case of timing though... accuracy isn't in fashion... exaggeration is.)

Anyway, here's the Seinfeld shot rendered (for some reason mental ray decided not to render my hair movement, although I've even baked the hair dynamics - but I decided I like it this way too, I'm done with this shot, and I want to move to something else and get to learn new things):

 
 

After a little bit of refinement on the animation, here's the latest edit (this post here will always have the latest edit, as long as the animation remains WIP):

Download the file for full rez: DOWNLOAD

 
Hips and Chest 03/06/2009
 

Today I'm posting a little bit of guesswork, or in other words: pose analysis from photos, with a focus on hips and chest. Lots of animators like to analyze lines of action, shape-stuff, and not so much anatomical stuff like chest, hips, spine, and the relationship between them. It's pretty hard to think in terms of "the real thing" and much more comfortable to just draw a fluid line of action. Not to say that lines of action are a breeze to master or maybe not even a big deal... au contraire. Lines of action are a thing to watch for in animation, and not only along the spine and limbs of the character, but also as a composition per se, the whole pose should flow naturally, and also in a group, multiple characters should have a visual flow.

Anyway, today is not about shapes, it's about rotations.... What does that chest do in a pose? Or the hips. The spine is then a result of the relationship hips-chest. Of course, in cartoony animation we can go crazy with the spine and not be bound by realistic limitations, but that's not what I'm analyzing today.

So, I'm considering X, Y, and Z rotations just like they are used in Maya: rotate X is rotation around the X axis, meaning mostly a bend backwards or forwards, rotate Y is basically the twist, and rotate Z rotates around the depth axis, meaning visually left-to-right rotations. Rotate Z is usually the easiest to understand. Some rotations here and there are less obvious, because of the camera angle, I'll explain later on.

One observation before we get started - the chest is a massive block, the spine starts bending immediately below it. The hip area is another, smaller block that doesn't bend (although the muscles, fat & skin (and clothing) do stretch over the rigid skeleton underneath, giving these blocks a not-so-rigid appearance). Some cartoony characters might be built to bend 100% all the way up and down, from neck to the base of the hips, but that's not what happens with real humans.

My victim is a pretty famous actress (she's pretty too. and famous. so there you go...). OK, she's dressed, so it's hard to tell sometimes exactly what's what, but I already said I'm doing some guesswork... following this post will be another one with nudes, where things will be clearer (although these things are never too easy or obvious anyway). Maybe I should do an analysis of nudes first and this post should be second, but eh. And to quote Forest Gump - that's all I had to say about that. Let's get started.

Pose 1

Notice I also added a green Center of Gravity bonus. I made it start from inside the upper-chest (I don't think it should be calculated starting with the base of the chest, because when the chest rotates, if the upper part goes left, the COG moves left as well, not right, along with the lower part. Not too sure of this, but guess I'm at least in the ballpark.)

Not much to say here, it's a fairly clean pose, the X axis is not much to talk about, nor is it too visible in this angle. Its effect on the pose is also not drastic. To be accurate, we'd need to judge in context - if I'd be analyzing from video it would be easier, because you can see where things come from and where they go. For example, as the chest is rotating from another pose, you can see what it does, relative to that pose.

Now here comes the issue of relativity. Poses are relative! To their neighbors. They exist in absolute space, but it's more important, I think, to get them right in relative space (one joint rotation relative to the rotation of other joints, and one pose relative to other poses). If we can get both spaces to coincide, it's ideal. More about this later.

By the way, when people talk about pushing poses, many times they mean - exaggerate a pose, some people might mean... push for accuracy, create a more accurate pose. I prefer this second meaning of "pushing" a pose. And this article is about trying to get as accurate as possible into understanding a few aspects of posing. I think accuracy is a huge thing, besides other principles of animation - by me, accuracy should be an animation principle ;) .

OK, a little bit about the Y and Z rotations - how do you tell in absence of other frames/poses what exactly happens. Because while it's easy to see what the limbs are doing, the hips and chest... are hard. My best answers for now would be:

1. stand up (or sit down, etc) and try it for yourself, to better understand the pose.
2. look at the limbs and what they are doing, their position is often a result of what the chest and hips are doing. For ex., here she has her left foot slightly behind the right foot, so that helps us seeing the hips rotating towards left (again, try the pose on your own and see that, in a relaxed pose, you wouldn't have the hips rotating backwards from this - meaning left hip goes with left leg and right with right.) Same, the arms show what the chest is doing.
3. use your common sense - the spine in this pose does look twisted, right? Important thing to know! And then... on to deciding what twists in what direction.
4. use your knowledge of anatomy and, hehe, body mechanics, as much as you can. This is a topic I seriously need to read more about.

Pose 2

Really hard to see what the hips are doing, but I'll be using my phenomenal guessing talents... basically, let's put it logically: she is sitting, so the Z rotation (meaning in fact the X axis - in yellow) is flat, or almost flat, parallel to the ground. But because of the camera angle, it looks rotated. Relativity!

The chest's Z rotation is... well, I might be wrong here, maybe it's backwards from what I've drawn. What we know is that she definitely supports some of her upper-body weight on her right leg. That should mean the right shoulder would normally be pushed upwards, and the relaxed left shoulder is left hanging loose. BUT! One problem with this pose is that she probably is leaning against the wall a little - that affects the weight distribution and the balance of the entire pose. So if the right shoulder leans more against the wall, it's then not pushed upwards by the arm.... so much... and the Z rotation I've drawn is correct. In context (video) I'd be able to tell better, but from a still... I just find it harder. It's a cool exercise nevertheless :)

The rest is fairly basic.

Pose 3

Even harder to tell what's going on without having full feet, but logically, she is placing her weight on her left leg, so the hips rotate as shown... X rotation is again obscure.

Chest rotation is - well, it seems straight, right? But relative to the hips, hehe, there is an angle. It's really hard to determine if the chest rotates more to the right or left... what do you think? (anyway, in this case, it's not so vital... I think... like... who cares? Or maybe, should we care...?)

Pose 4

See how the camera angle makes things hard to read... What's the chest Z rotation? Seems flat. The Y rotation is also obscure, but for the hips, based on feet position, I've deduced the above drawing... The thing is that in subtle poses like this, you might look at it and think you understand what's going on, but be wrong, and look at it from a different angle... and again it looks like it makes sense... but you might again be wrong. But if you can see the movement in context, it's easier. One question for this pose would be - is it static? Maybe. Logically - yes. She is posing. But what if she is captured during a move? That changes things - the balance changes if the pose is dynamic, if she's during a weight shift for example.

Pose 5

Again, we can't see the legs. The clothing also makes things hard to read. But luckily the pose is quite strong. She has her weight on her left foot, but is the right foot in front of the left? Possibly.
In that case, the hips blue arrow should be the other way around. But to me it looks like it rotates as shown. Might be an illusion. Anyway, the fact is that the chest, relative to the hips, is creating a twist, and the chest Y rotation is more obvious (we do see the hands).

Pose 6

The twist is obvious here (but do notice how the hands are working against the body twist), but the Z rotation not so much. Notice how the COG line starts inside the chest. No obvious X rotations, very subtle... maybe the chest is rotating towards the back a little.

Pose 7

This is a cool one. The chest tries to balance the pose by going against the hips. The line of action of this pose would be round along the spine, right? The pose looks simply... round... but in fact, because the chest is rotated the other way from the hips, we have an S shape, not an inverted C. The hips Z rotation could be sort of... flat, but I think it's actually leaning a little towards her right.

Pose 8

OK, completely obscure hips, except for the X rotation which is really clear. The chest is clearer - there may be a little forwards X rotation, and the Z rotation is not vital here, I guess... Very subtle anyway, and hard to see from this angle. Cool pose, hihi.

Pose 9

OK, she's sitting, so that means the hips are flat against that surface. All the weight is there, although there might be a little of the chest's weight on the hands too, not sure exactly how much. The X rotation, if there is any, is subtle. The Z also, it could actually be the other way around.

Pose 10

Oh, yeah, this is not Calista. Ooops. Ammm, too late now... hehe.

But do notice how on a fairly undressed body things read much clearer - even in the absence of the feet contacts.

So why did I do this analysis on Calista, why not on naked bodies with complete poses?? For fun :D and... also, I think I learned some things, because I had to struggle to understand what was hidden. But for fun, mainly! You can't argue with that :D

That's it for now. If anyone thinks I'm wrong with stuff, please post and let's debate it.

 
 

OK, here's a first run through fingers animation.

Low rez version (2.3 MB):

And high rez version (4.5 MB): DOWNLOAD

 
 

Here's a first look at my Seinfeld shot. The audio is very clear, so I won't transcribe it. It's a work in progress, and I only animated the body, no fingers, no face. 1.3 MB

 
 

Besides being functional, a pose should also be appealing, it should look good. Right? But... is beauty only in the pose, or is it also in the model?

For instance, if you are truly ugly (it can happen), you look in the mirror and from no matter what angle or pose... you're going to be... ugly. If you're a gorgeous babe, you look in the mirror and in almost any angle and pose you're going to be gorgeous... Pretty simple. But why don't animators care much about this, I wonder?

If you animate an ugly model, no matter what you do, your animation is going to look bad. It could move naturally and have personality, all that jazz, but the poses will still lack that graphical appeal that makes a drawing a pleasure to look at. It's easy and only natural to amazed by beautiful imagery, and it's something animation also needs, among other things. An ugly model can't possibly be posed to look beautiful.

Yeah, on the other hand, you could mess up a great looking model too, if you insist...

Anyway, take the (in)famous Generi rig for example - no offense but... the guy looks monstrous and awkward... (I mean, I apologize to the creators, but I really want to point out some things here)

(Yuck! Stop smiling..... it hurts.....)

There must be hundreds, if not thousands of animated shots done with Generi, and they all look unappealing. Is it because the animators have never managed to reach that level of... ammm... I don't think it's because the animators using Generi are unexperienced. Some of them actually are talented and do have experience. OK, maybe he can be funny, and even look cute to some, and maybe some people are, by now, so used to his design... Generi definitely has a place in the history of computer animation. But not even accidentally could you create a trully appealing pose with a truly unappealing model like this. I'd simply like to see anyone - the best Disney animator - try to create ONE appealing pose out of Generi (maybe if you hide his face...?).

Oh, and there's more, it's not only Generi, there's a whole bunch of free rigs out there that use unappealing models. Appeal is a matter of design, and it's damn hard to create a 3D puppet that looks great, it's just hard.

 
Basic Lip Sync 03/06/2009
 

Well, maybe it should be called - basic lipsync looking good and done fast. All very juicy stuff, concerning, I think, the most important (and basic) aspects of lipsync.

First of all, the bulk of lipsync is in opening the mouth on the main beats. Just use your own mouth to discover what those are - for example, in the word a-ni-ma-tion we don't normally open the mouth on every syllable, we open it only twice: 1 on ani and 2 on mation. I'm talking about the main mouth movements - if you open and close the mouth on every syllable, you get a machine gun lipsync that looks horrible, like that resulting from automated lipsync.

Second important thing would be to close the mouth fully only on Ms, Ps, and Bs. And you have to close it, and keep it closed for at least 2-3 frames, or your lipsync will look off and floaty. So in our example: ani-mation we open & close, keep it tight on M and open & close again.

Step 1 and 2 would be enough to get you basic lipsync that looks OK and very readable on a simple character. It's really important that you get the mouth opening and closing right, and time this really really correctly. These are the main pillars of lipsync, everything else... you simply build around them. If the pillars are timed incorrectly, if they don't hit the main syllables properly, you can polish your lipsync forever, it will be off.

Third important thing is: OOs and EEs. After you get the main pillars right, add in some OO or EE wherever necessary, but keep these relative!! By relative I mean - their values should be relative to their surroundings. An OO doesn't have to go all the way down to a full OO to feel an OO. If it follows an O shape, yes, it should go more extreme than that O. But if it follows an EE shape, simply reducing some of that EE can be enough to make it feel like an OO. Take our example - animation - the first mouth movement is ani, we slide from a default position (for the sake of simplicity we'll start from the default mouth) into a little bit of EE, and we go back. We fully close the mouth, we might even go a little bit more towards OO during the close, and then, as we open again on mation, we do the same slide into a little bit of EE ad back again as we close the mouth. Now this little bit could be just a little bit, or maybe a bit more, it's up to you to decide what looks good, and oh yeah, it all comes down to the soundtrack - whether the voice is calm or agitated, etc, that will influence the look of that mouth significantly. You could speak on a side, barely moving the mouth, you could move the mouth left to right during speech, you could exaggerate or reduce intensity, shapes, etc. All lipsync comes on top of facial expressions anyway!! This means it's a good idea (see what Shawn Kelly says in an older post you can read here) to animate lipsync last.

Less important, but easy to do and very very cool is to keep the jaws loose: move the jaws left and right along with the main mouth openings - if you track the tip of your character's beard you should normally get nice round curves and figure 8s. In our example, on ani and mation we could have 2 ovals, one for each mouth opening, or maybe one figure 8 starting at ani and ending at the end of mation. Keep this jaw movement more or less subtle, and maybe only have larger jaw movement on the main shot accents for example. Like: "WOW, this is pretty cool looking animation..." could have one big mouth accent on "WOW", of course... and then all the rest is kept subtle, maybe with some intensity on the word "animation", especially on the second beat - "mation" (while keeping "mation" though... say... half the intensity of "WOW").

There are other things involved in lipsync, obviously, but I consider them to be details - as you get in detail... you start being concerned with more exact mouth shapes, with Fs and Vs and Ts and Ls, and whether you want to show any tongue movement or not... (normally you should, at least on Ls, Ts and THs).

Finally, as a conclusion - if you only have one controller (!) to animate lipsync, that controller should be able to open & close the mouth on the vertical, and pose the mouth from OO to EE on the horizontal. With only one controller you can get decent simple lipsync that's done fast and looks natural.

 
Head Tilts 03/06/2009
 

Head tilting is a major part of an appealing pose. That's what I think. Of course, you don't tilt your head aggressively all the time!! Just a little bit, or maybe... a little more than just a little bit... you can find tilts in pretty much any pose. I'm just observing here, this is not a recipe. I don't usually like what comes out when animators follow too many recipes instead of focusing on real performance/acting.

There are many reasons for tilting your head, and perhaps one of the most common is the need for balance. In cartoon animation especially, many poses are drawn to follow a round C curve or S shape, and it's called Line of Action. In the rat below you can draw a smooth curve along his spine and head and legs too. The head tilt here is just a natural continuation of the body's line of action (btw, notice the rat's right hand looks kind'a stiff, hehe - this and the following rats are taken from the Ratatouille teaser and trailer).

This cartoony, graphic principle, goes actually hand in hand with a real world phenomenon - we balance our heads and bodies all the time. A twist of one body part can generate another twist of another body part, in either the same or opposite direction. Balance is achieved through opposites though. Look at this guy (this and the 7 following images... not containing rats... are taken from the excelent movie - Little Miss Sunshine):

His head seems to want to stay straight while the body twists, creating an arc, like an inverted C shape. This is what it seems at first glance, but we'll be back with this example in just a sec. Because it's actually not the need of the head to stay straight that we're examining here, it's the contrary. The head does need to stay straight so it can get a clear picture and function in optimal conditions. But its "straightness" is not that... straight all the time. The head needs to stay straight, but it often finds itself doing otherwise. OK, so from here on I'm only talking about tilts. Tilts occur in so many cases that's just ridiculous... but most of them are fairly subtle. It's almost like saying - the head is straight... but in effect it's not. I've given examples of more extreme tilts in this post though, just to emphasize the fantastic appeal of head tilts. Oh, and I'll only show left-right tilts, which I consider more special and appealing (backward-forward tilts are pretty basic, and everybody is using them all the time - well, OK, one thing about backward-forward tilts - I love how the Muppets keep shaking their heads all the time, now that's a brilliant caricature of real head movement, typical for the puppets-animation medium, but just... unique in that specific way it appears in the Muppets).
Look at me, I'm so tilted...

Notice how both characters are tilted towards their right.

Yeah, I'm looking. And guess what. I can tilt left too...

From the same shot as the first image - notice the line of action has changed from an inverted C to a C shape, the head tilting with the entire body from right to left (I always refer to the character's left and right).

Look at us tilting an twisting... aren't we cute? (Notice how their bodies are tilted towards each other, while their heads are tilted in parallel, towards their right)

OK, if you think this isn't such a big deal, let's look at real world examples, where you'll see that tilting heads are actually really going wild (it's weird that a cartoon doesn't use tilting more than real life... Could it be because the artist's eye has the tendency to straighten up and smooth out things...?)
OK, look at these guys and notice how tilted their heads are...

And then how they keep tilting from left to right

And btw, the kid in yellow is not talking, and he's kind'a stiff and ignoring the rest of the table. Yet... he does change his pose quite a bit. And he tilts with (or against) the rest of the group, hihi. They're like trees swaying in the wind...

Back to the guy in blue, and his family. Notice the variety of tilts :D

OK, and now look at the blue guy again:

Is his head tilted or is it his body? Well, in the above image, his head is almost straight, while the body is tilted. But actually as he stands up and walks, we see that his head keeps a similar angle with the body, and becomes tilted. Hihi. It's part of his current attitude.

And here... the whole gang seems to want to be tilting right (maybe it's the road...?). Yeah, except for the guy in white who's so stiff (he's got his reasons allright) - so maybe it's not the road...

Let's go and see more tilting examples. (This and all the following images are copied from various internet sources, if anybody is offended, please let me know and I'll take them out. Oh, and please don't sue me, I'm one o'them good guys...)
Why do people tilt their heads left-right?? Weeeeelll, maybe they need to fit in the picture...

Maybe it's their job...

Maybe they're trying to impress...

or to relax...

Kids do it a lot... all the time...

Even at an early age...

So why shouldn't divas do it?? They know it's sexy and appealing. Especially women!

OK, now maybe someone's trying a bit too hard here... look how tilted this head is... craaaaaazy :D

So women I guess were the first to realize the head tilt looks really good on a resume...

And got to real extremes...

While men were soon to follow... slightly more serious...

Tilting your head is good for your health too...

...aaand in case you need to scratch like a monkey... now that's some tilt!

Dogs do it... the love doing it!

And other animals too (even if it's sometimes a disease - yeah, poor fella', he's actually ill, looks like some animals have this disease that's called... head tilt, weird, huh?)

Some people do it sometimes in pairs...

It's being done successfully in other countries as well...

You wouldn't think this is much of a tilt, now, would you...?

...but look again (actually this pencil is a little off, and the tilt is slightly more pronounced).

Well, OK, finally, if you don't know how to do it (hihihi), here's a scheme...

Edit:
Along the same line, things should generally be not too straight in a pose for them to look natural. Here's an image from someone else's blog...

that underlines this clearly (although I think he meant "unless the pose calls for a straight... line of action" or something like that). Of course, there'll be times when you need a pose to be rather straight, uptight, but that should have a solid reason in the acting context. For natural, live, appealing poses, lean, twist, bend, tilt... just don't overdo it, don't completely mutilate the character :D The hardest thing in a pose is balance. But it's also probably the most beautiful.