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Art Journal 015: Weightiness
🕑 Added 2014-08-22 09:43:31 +0000 UTCEveryone knows having a reasonable understanding of anatomy is important to drawing people. Even if you choose to bend the rules and draw cartoony it behooves you to have a working knowledge of how the human body is built so your abstraction into cartoon is informed and makes sense. It’s a story we’ve heard time and again, but there is an important distinction which I feel gets overlooked quite often: anatomy does not exist in a vacuum! No! In fact, more often than not that anatomy is going to exist in a context which implies a gravitational pull weighing down upon your characters and the worlds they inhabit! This week, by request, I’m going to explore how to make things look weighty and massful, and how to give our figures that lively feeling of being trapped in the unwavering grip of your host planet. I took some time and drew up little diagrams to visualize the topic so I will be referring to the above image throughout this post with parenthetical annotations, since I feel this is something better shown than told.
A good way to think of mass is a force being exerted downward onto a body, rather than a force pulling from below. An abstract way of thinking of it is the gravitational force below your world isn’t just pulling down on your characters, it’s pulling downward on the atmosphere above and around them as well. This is less apparent in the air but it’s a big reason why if you go too deep underwater you’ll be crushed, that’s the weight of all the water above you crushing you down against the water beneath and around you. Either way, I tend to imagine gravity as an invisible weight on your shoulders, and to help illustrate the point I’ve drawn a weighty, meaty little model to demonstrate this phenomenon.
I’ve chosen a thick stocky person (fig. A I) because their body has a lot of weight itself and so it will better show what I mean. When we imagine a body, don’t simply think of it as the outline of a torso on top of some legs with a head and arms coming off the side, try to think of it in terms of its component parts, like stones, boxes or bags of sand hinged and mounted together. Each of those components has a degree of rigidity to it, defined by the bones beneath it, but it also has some squish and stretch as well, which we see in the compression of the meat around those bones. When standing idle that mass will settle around the body’s primary structural support, which is usually the spinal column. In the above figure the ribs are a weight in front of the spinal column, so our weight tends to settle forward into a slouch. We indicate this with the position of the sternum at the center of the chest and the position of the head in relation to the shoulders- namely in how the shoulder line bisects the head, and we have a round look at the base of the neck from a more forward angle rather than a neck straight in the air, this gives us the sense that weight is pushing down on the point of least resistance and the mass of the figure follows. Coming off our shoulders we have huge treetrunk arms, very massy, which gently curve from the horizontal line of the shoulders to a mostly vertical orientation in the radius and ulna. Internally these two bones, and the humerus of the upper arm as well, can form this obtuse angular shape at the joints of the shoulder and elbow, and the softness of the flesh around them will not only suspend them at that angle (rather than falling straight down at the meat person’s sides), but that flesh will also soften the sharp bony angle into a gentle sloping curve, this malleability giving us the rounded profile we see from elbow to elbow across the shoulders.
Below the ribs we can see a compounded effect of the gravity that pulled down on our figure’s shoulders combined with the weight of the top half of the figure pressing down on the bottom. The lower section of the spine compresses and curves under this weight- whose curve feeds into the upper back’s curve leading into the angle of the neck supporting the slouched head- and the flesh around it gets squished. Unlike the upper torso, which is supported by the rigid framework of the ribs, the lower torso is mostly guts and soft tissue so it’s much more free to stretch and compress, but since we’re examining idle weight right now it’s compressing. The legs are the two things keeping this whole lump of meat upright and since they’re under a lot of weight they’re not going to be totally straight. The bend at the knee informs a degree of distress being placed upon it, not unlike when you hold a credit card in profile and press your fingers down on it- what is otherwise straight takes on a distinct bend as it redistributes the load its bearing throughout its arc. And of course the feet are flat and firmly on the ground; there’s not a lot of leeway for tippy-toes and the body above them is not showing any sort of resistance so they’re going to be flat under this weight, and thus we illustrate mass!
Not every body will react to gravity in quite the same degree of exaggeration- and that’s part of what makes us all different!- but the principles are pretty consistently the same. Short or tall, thin or thick, our bodies have roughly the same internal components so we’re rigid and bend in similar ways, but depending on whether we carry more or less meat and muscle around those bones we may sag or stand more rigidly than our neighbor. The core element behind our entire anatomical framework, as mentioned earlier, is the spinal column. It’s not a column in the Ionic Pillar sense of the word since it’s absolutely not a rigid vertical structure. Instead, our spine is best thought of as an S-shaped spring (fig. A II) which is bent and contorted in just such a way to distribute weight evenly throughout without its central point succumbing to crushing weight from above and below. When we draw a standing figure our posture is distributing weight throughout the body, and it can do so in a number of ways. As illustrated in our Meat Person a square-shouldered, square-hipped body can slouch forward to distribute their weight, but an upright body can also even it out from side to side. A simple skeletal figure demonstrates thusly (fig. A III). Here we can see the S-shape of the spine in a less dramatic sense, our feet planted on the ground and our head held high. The vertical dotted line through the figure represents a center of balance- as a rule of thumb, when you toss your hips and shoulders all willy-nilly as long as your head stays between your feet your figure will appear balanced. And speaking of hips and shoulders, note how ours aren’t as parallel as our lumbering friend in Figure A I are. This figure’s hips and shoulders are perpendicular to one another, meaning if we drew a line through them they will intersect at some point. This indicates that our spine is maintaining its natural S-shape as our figure stands upright. Our knees are straight this time, they’re not bearing the load like our previous example are. Instead they’re locked and weight is balanced at the hips- the angle of the hips allows the legs- which are of equal length- to connect at a higher and lower joint relative to the floor from one another and still maintain a flat-footed sense of balance. The spine contorts, the body is slightly compressed, the legs support it, the hips bear their load and our figure looks lively and weighty! By contrast, our other friend here (fig. A IV) has a ramrod-straight spine and square, parallel shoulder and hip lines. This one isn’t distributing weight by slouching or settling it on their hips so it looks like there is no force acting upon it. It appears completely rigid and column-like, which anybody with a body made of meat can readily identify as abnormal. There’s no play at the joints, there’s no balancing going on, it’s just a rigid whosit standing in their wherever. That’s no good.
So we’ve explored how gravity imposes itself on a standing body and the way that body works to distribute its weight, but what happens when we’re not standing? What about if we move? Well, to illustrate this point I’ve invited The Ball Who Is Filled With Fluid to join us. Our bodies are about 80% water, mostly manifesting as squishy guts and flabby meat with the occasional bone here or there to prop the whole thing up. Bones notwithstanding our spherical friend is roughly the same. This fluid nature is important when we start moving around because if we can imagine the sloshing effect of all that water we can get a pretty good idea of where our mass is going to go when we ourselves are on the move. In our first diagram we can see our spherical friend suspended weightless in the air (fig. B I). Here they’re perfectly spherical and they have roughly an even distribution of water in them. It’s cute, but we’re here to learn about gravity, so let’s turn it on and see what happens. Now succumbing to the forces that bind us all, the fluid-filled ball falls and impacts the immovable force of the floor. Since the ground is usually firmer than our bodies, its us that does the squashing as we redistribute the energy of our momentum and sudden halt outward around the point of impact. In our ball friend’s case, that means squishing out like a thick round-topped pancake (fig. B II), all of their fluid now pressed to their bottom. This state is not unlike the state our bodies take when we push off one foot to take a step- our body comes down to plant a foot on the ground and then push up again, but the momentum of our mass is still carrying downward as our bodies reverse direction and go up again so our weight tends to settle low, like its a moment behind our skeletal pace. It adapts, though, and as we’re taking another step our mass rebounds and tends to go up with the rest of us. We can see this effect in the rebounding bounce of our fluid-filled friend (fig. B III) where all of their fluid mass has settled high on their body, elongating it upward. Our mass follows our momentum upward, settles slightly and when we descend from our apex to bring our foot down on the ground again, and after a moment settled high we impact the ground and it drops low again and the cycle continues with the next step, shifting to the left or right sides of our bodies depending on which foot we’re landing on (it’ll tend towards the half of us that does not have an impacting foot on the ground, if we remember how the rib/spine dynamic of our fig. A I meat friend works) and onward we walk. We’re basically sloshing bipedal bags of milk and we don’t move rigidly, our spines stretch and compress under the weight its carrying and our flesh, hair and clothes bob and slosh around our frames. If we were to just sit and settle without the benefit of weightlessness our mass would tend to settle downward, shaping our spherical friend more like a gumdrop than a ball (fig. B IV). This is why when we sit down our midsections tend to compress and fill out and our butts sorta squash, it’s weight coming down on top of a soft bag of mass. Pretty easy to visualize once you get the feel for how it all works, right?
Like our bodies, our lives don’t exist in a vacuum either. We’re humans, we’re tool-users, so we tend to use a lot of tools in our daily lives and those tools tend to either balance or unbalance in our hands, so if we want to represent their weight correctly we need to understand how that weight is distributed along a rigid non-meat-based object. To help us demonstrate this principle we have a friendly anonymous hand. A good place to imagine balance in a tool is across the top of our base index finger knuckle- if you’re holding something like a stick, a hammer, a screwdriver or a popsicle or some other top-pointing thing in your hand and you open your fingers, that is the point on which it will pivot, so that will be our reference point for exploring balance. Our first figure (fig. C I) demonstrates something with a consistent weight to it- this would be something like a wooden dowel, a length of pipe, a pen or a pencil. Its weight is fairly consistent throughout the body so if we find its fulcrum (the central point of balance) there will be an even amount of the object on either side of where it pivots. In this example the weight on either end of our object is roughly the same so its fulcrum is in its center, and we can balance it across our hand easily. If we were to grab one end of it the other would not have a noticeable pull or weight to it because neither end is more massy than the other. But what if one was? The object would still have a point of balance, but it would shift away from its central point towards the heavier side. In our second example (fig. C II) we have an object where one end has significantly more weight than the other- this could be a hammer, a wrench, a really big lollipop or some other lopsided item. In our example here we can see where the center of the item’s length is- marked with a tic mark- but we can see it doesn’t coincide with the object’s fulcrum! The lighter weight on the far end can balance the heavier weight on the near end but it needs more length to allow it the leverage to find that balance. In terms of tool usage we would normally flip this object around so the heavier end is the far end and we’d grip the lighter end to keep it from falling away, and its lopsided weight would be useful for generating force. It would also tend to pull the angle our hand sits on our wrist since its downward weight becomes a force our hand has to control. But do we necessarily have to flip this example object to make it useful? No! Swords are romanticized weapons and they feature heavily in art and stories, so it’s worth noting that a well-made sword’s center of balance sits just at the base of the hilt, meaning the long, long blade of the weapon would be balanced against the relatively-shorter grip of the handle we’re meant to hold, with its fulcrum sitting right above our index finger. We can see that principle demonstrated in our vaguely-familiar butterfly knife (fig. C III). This is an example of how something with an inconsistent distribution of mass can be made to feel balanced and weightless- an object balancing in this way would suggest speed and cutting power as opposed to our bludgeon example from earlier, even though each has a similar distribution of weight on one side of its fulcrum. Balance isn’t a strict matter of X=Y with one half of a thing equalling the other half, but rather X*A=Y*B, where A and B represent the length of body on either side of the fulcrum relative to inequal weights X and Y. It all balances out! It’s not magic, it’s math.
We’ve seen how our bodies settle weight and how we can balance objects on a single point, but I’d like to show how to suspend an object across two points as well to round out the article. Since our waitress friend Lizzie does a lot of lugging her long, lopsided mop around in the gravity-filled world of her comic she tends to carry it on her shoulder. The mop is a long piece of wood with a hunk of rusty metal on one end, with moppy strip parts hanging off the end of -that- which themselves can either be light or heavy depending on whether or not they’re soaked with fluid, so we have a long object with a complex but very one-sided weight to it. If we were to hold it straight up in the air with two hands its weight would pull straight down (fig. D I), as indicated by its mop bits. Our two hands hold it in place at two points so neither can be the pivot and thus we have stability. But if we were to take one hand away and open our fingers on the remaining hand we would create a path of least resistance across the top of our index finger’s base (since our open fingers lose to the rigidity of our palm) and the weight at the top of our mop would tend to pull it across our hand (fig. D II). This is a demonstration of its uneven weight acting out of balance, which might sound undesirable on paper but is actually a very useful property for casual transportation. Our mop as a fulcrum higher up its length near the weighty moppy end and we could rest that point on our shoulder and it would be perfectly balanced, but that would be unpleasant to walk around with since the end we’d be holding would rattle around inside our hand trying to maintain its center of balance in tandem with the rise and fall of our footsteps. So what we do instead is we let the fulcrum of our mop hang off the back of our shoulder in an unbalanced state that pulls the mop-end down towards the ground below us. By deliberately off-balancing the mop on our shoulder the lighter end pulls upward against our hand and we don’t have to really do anything to stabilize it but keep our hand in place, we don’t even need to grab hold if it at all. By using a two-point system we can balance an unbalanced object by restricting it from moving in the directions it wants to go- both our shoulder preventing gravity from pulling it downward and our hand preventing the tail end of it from pulling upward in response to the downward weight of the end hanging over our shoulder. I tend to visualize it as sort of an S shape; S for Stability. When we draw this we want to make sure these two contact points are maintained- both the object resting downward on our shoulder and upward against our hand, otherwise it’ll look like we’re just awkwardly holding it at an angle over our body. We can even demonstrate weight in how that object interacts with the carrying body’s sense of balance- by making the side of the shoulders supporting the object the downward-sloping side of our perpendicular angles (fig. A III) we allow our figures’ bodies to look like they’re reacting to and supporting the weight of some hefty object, distributing its added weight- whether its slight or massive- throughout the coiled spring of their body. It all fits together, thumbs-up!
Weight is a tricky thing to get the hang of but if you’re mindful of it and you explore how different objects in your world feel, or how your own body moves and balances itself in a mirror, you can build an intuitive sense for how things roll and tumble in our hands or how our bodies stretch and sag under their own weight or weight imposed upon them by outside forces. Conveying that in your art is often a matter of subtlety and deliberation, figuring out why the details work and how they fit together with the rest of your scene. Once you get the hang of it you can’t “weight” to find new ways to explore mass and heft!
Thanks for reading!
