moving with NPCs

"Follow me!" the NPC says. So I do.

Well, I try to.

When I walk, the NPC is moving faster than me. I fall behind. When I run, the NPC is moving slower, and annoyingly alternates between walking and running because he or she is incapable of matching my pace precisely.

Why is this a problem? Why does it show up in every single game that has me follow an NPC or has an NPC follow me?

enemies with personality

One of the reasons I expect Borderlands to be a lot of fun is the dynamic comments that give individual enemies personalities:



The amusing outbursts of enemies makes them more than just faceless meatbags. The Halo series has proven how effective this can be.

Giving enemies dynamic outbursts does two things. First, it adds a personal dimension to combat, making it feel like your actually fighting individuals and not the Borg. Second, it adds variation and replay value. It can make one enemy feel slightly different from another despite both using the same model and the same AI.

This isn't only possible with human enemies. Individual dogs of the same breed can have different barks. Individual skaags or other beasts could have different growls, screeches, etc. Voice variation with animals and monsters has an effect similar to that with humans.

Nor does personalizing individual enemies have to be done only through modeling, AI, and voicing. There's also animations. Slightly different hand motions, ways of walking, relaxed and defensive stances, and so on can make enemies which are otherwise the same feel like true individuals.

Every aspect of NPCs changes the experience.

body language

As I said yesterday, technology might soon enable game characters to respond to players by reading our faces. There's a flip side to that. Players could better respond to characters if facial animations and body language were improved.

The most basic benefit of this is obvious: improved empathy. A character's dialog and actions have more emotional impact when those actions correspond well with the character's physical expressions.

Another benefit is to replace dialog entirely. Animating is not simple, but it's cheaper and easier to refine than hiring voice actors. It also saves valuable memory space. Silent expressions often have the greatest effect. But I expect refining such animations would be very difficult, considering that even good actors have difficulty replicating some emotions, like despair and terror.

The use of animations that brought this subject to mind is translation. Having taken many linguistics courses in college, I know that not all body language is universal across the globe, but the basics are.


On the one hand, you have games like The Saboteur. The game is set in Paris, so one might expect some of the dialog to be in French, even if the majority is English with a French accent. A bit of dialog local to the setting can add flavor, and good body language can make that dialog more meaningful.

On the other hand, there's the inherently national nature of any game. Games published worldwide either pay translators to adapt the dialog or apologetically ask foreign players to enjoy the game as it is. Something is always lost in translation, and body language helps to counteract those losses. And while great facial animations won't allow foreigners to play a dialog-centric game, it can be pivotal in action and puzzle games for making environmental dialog bearable.

Anyway, the usefulness of better facial animations and body language in games seems obvious. What's less obvious is whether or not each developer must tackle this issue on their own. Might it be possible for a company to develop a program for such animations to be used in a wide variety of games by different developers, similar to something like SpeedTree? Or must representation of the human face evolve only as a collective effort, like the modeling of skin or eyes?

kinetics

I bought Sacred 2 for my 360 when it was released, and traded it back in only a few days later. I didn't even want to make use of my money before getting rid of it. So I agree with GameTrailers' review, as usual. But I'm surprised kinetics was never mentioned.

I call it kinetics, but there might be a better term. What I'm referring to is the feel of action: the way animations and sound effects combine to bring actions to life.

Timing is key to kinetics. Imagine a baseball game. When a player swings his bat, is the animation slow or fast? Either could be fun, but the speed affects the feel. Now consider the sound. Is the crack of the bat against ball perfectly synched with the animation? Or does the sound come a split-second before or after the animation?

Now imagine there is no sound when bat meets ball. That would suck, wouldn't it? No game would forget to include that sound. But what about surrounding sounds? Does the crowd cheer when the batter gets a hit? Does the crowd's noise change at all depending on whether it's a home run, a grounder, or a bunt? What about the player's footsteps as he's running to 1st base? Does they get any sound?

Does every player throw or drop his bat the same way? Does every player swing the same way? Do they all run with the same gait?

The point is that even simple actions can have surprising potential for accompanying sounds and animations. And, generally, the more visual and aural details included, the more compelling an action feels.

So back to Sacred 2. Play that game, Play Diablo 2, and tell me which has better kinetics. Compared to combat in Diablo 2, combat in Sacred 2 feels like flag football. There are more sounds, including reactive lines of dialogue (not commentary... screams, yelps, and such), and animations are quick enough to keep combat tense and frantic. Titan Quest also fails by slowing animations and creating a slight disconnect between player attacks and enemy deaths and defense. That one's a good game, but the timing is slightly off and dying enemies often float in the air a moment.

All games are limited by time and expense. But pinpoint the actions your players will employ most often and devote as many sound effects and animations to those actions as possible. Other parts of your games can be sketched simulations, but core actions should be represented as fully as possible.

better quick-time events

When I heard that Dante's Inferno will be full of quick-time events (QTE), I sighed in disappointment. I later made a comment that QTE are often fake participation. I'll explain what I meant by that.

I'm not completely dismissing QTE as a viable game feature. How could I? One of the industry's most popular game series, God of War, has thrived on them. I've never played God of War, since I never owned a Sony console (due to limited money -- not that I've never wanted one). I can't comment on that game. I've only experienced QTE in other games, and those experiences haven't been fun.

What I object to isn't the basic idea of simple actions that facilitate a cinematic experience, like climbing a gigantic monster. What I object to is purely reactive button-mashing... a complete disconnect between what the player is doing and what is happening on screen.


There's a great scene in one of my favorite movies, Fierce Creatures, where a zoo's manager leads his zookeepers to a large cage with a panda sitting amid the bamboo. The zookeepers coo and smile... until they realize it's an animatronic panda! It's in a cage for viewing as if it were a real animal, but it's really just a robot. The ensuing conversation goes something like this:

Staff: "You can't put an animatronic animal in a zoo!"
Manager: "Why not? It gave you a thrill."
Staff: "But it's not a real thrill, is it? It's artificial!"
Manager: "Having pandas in England is artificial."

The zoo manager clearly has a good point. We could fill our zoos with fake-but-convincing robots and there would still be a thrill to be had by audiences. So why don't we? First, because we value truth, and people shouldn't be intentionally fooled unless they want to be (like with magic shows). And second, because real animals can offer a grander, better experience.


Quick-time events, like any other design concept, can take many forms. The QTE that I've seen is basically like that robotic panda in the zoo. By making the player react to a series of random button requests ("Press X! Press Y! Press X!") to unlock parts of a scripted animation, these games are faking participation, in a sense. The player's button combos have no real relationship to the character's actions. Players are just jumping through hoops.

In such games, participation isn't really a significant source of enjoyment. The player's thrill isn't from the whack-a-mole action... it's from whatever epic event that action unlocks. Seeing my character climb on the back of a huge beast and stab it in the eye -- that's awesome. But while I'm concentrating on reacting to random button prompts, I'm not watching the monster. The experience is schizophrenic. The player is distanced from the action, rather than given opportunities for true engagement.

So how would I do it? What's a better way?

One example of making quick-time events truly participatory would be to mimic Assassin's Creed's acrobatic system and place the grapple points on live enemies, rather than on structures. In Assassin's Creed, every building has been strategically covered by the designers with edges and objects which the player's character can grab onto. If monsters and such were designed with grappling points like this, then gameplay could be designed to let players climb them in a dynamic, intuitive, and player-directed way.

That sort of use of QTE means each player can have a unique and personal experience based on individual decisions and circumstances.

One player might go up the giant's arm, another up the back, another latching onto its weapon or facial horn when it attacks, etc. The enemies could be capable of shaking the player off, grabbing him, or crushing him against a wall... thereby making the player's anticipation of these actions and scenarios part of the gameplay.

For example, the player's character might climb on a monster's back. The monster responds by trying to slam its back against some rocks. The player sees this coming and quickly shifts the monster's head or arm. He stabs the monster in the neck. The monster howls in pain and reaches to grab the player, but the player shifts again to the monster's back and stabs it again there.

The game might even get really crazy and allow another, smaller monster to see the player on the giant's back and climb onto the giant's back as well, trying to bite the player.

Anyway, that's just one way quick-time events could be implemented that would allow players to truly participate in the events and never lose focus on the real experience: the enemies and setting. Hopefully, Dante's Inferno will surprise me with something like that.

playing with fear

The faces of fear
In a college course I took on Gothic literature, I was taught that the readers of Victorian England distinguished between two types of fear: horror and terror.

Horror is the fear from which one flees. It is obvious, bold, and usually aggressive. The creature in the movie Alien is a horror, as most monsters are.

Terror is the fear that paralyzes. There is an element of mystery about it that makes the victim immobile with wonder and uncertainty. Ghosts tend to be terrors, as are cool-tempered murderers and vampires. Terror is often accompanied by what Freud labeled the uncanny... the feeling of something being strange but somehow familiar as well.


Which face to show?
In every aspect of a story's presentation, frightening objects are capable of being either horrifying or terrifying.

A harsh, guttural roar will cause a player to run from the sound. The muted gurgling sound of someone being strangled, on the other hand, will make the player cringe and look for the source of the sound ("Is it a strangling sound? or is it something else?" the player wonders). A snake-like hiss causes the player to recoil and prepare for danger. Heavy breathing and wheezing in the darkness raises the player's curiosity. Screams and whispers evoke different responses.

Slow movements and villainous smiles attract attention, while ferocious charges and the fiery collapses of structures tell the player to get moving. Gargoyles and malevolent artworks invite the curious eye, but spikes and electric sparks encourage one to keep away.

Quick, bitter bursts of angry mutterings raise one's defenses against imminent danger. Slow, graceful, philosophical eloquence invites the player to be caressed by beauty within the darkness. Words can contain fire, or they can contain poison.

Enemies can hunt the player with brute determination, glaring hatred, and barking bloodlust. Or evil can be clothed in charm and elegance, pursuing the player patiently, teasingly, even affectionately. I'm talking about AI here, by the way. ;)


Toying with expectation
Building a particular, fearful expectation in a player and then revealing the source to be harmless can have two effects: (1) it can make the player paranoid, or (2) it can make the player skeptical. Either result can be good. The paranoid player's tension makes even harmless surprises eventful and raises the severity of the scare when he encounters truly fearful beings. The skeptical player's mistrust and constant questioning of her own expectations monopolizes her thoughts and makes her slower to respond to real danger, potentially giving the danger a brief advantage.

An exhaust hose can sound like wheezing. A flap of plastic can sound like a scurrying animal. Scraping metal can sound like screaming.

Doll parts can look real until you see the stuffing. Water and veils can distort things beneath/behind into startling images (such as faces). Crystal and glass can make things seem bigger or smaller.

Language can be ambiguous (intentionally and unintentionally). Personalities and cultures can include misunderstood tone-of-voice, expressions, and customs (a player could be frightened away from allies by such customs, like an assertive tone mistaken for aggression).

NPC actions (scripted or AI) can be purposefully erratic or nonsensical. Why did that young girl gleefully leap to her death? Why did that madman stop chasing me halfway down the hall and start staring wildly up at the ceiling?


Rewarding the steel will
One fun feature to put in a horror-survival game might be to award morale bonuses to either the player or enemy depending on the player's initial reaction. If a monster leaps out of the darkness and the player steps back in response (gives into fear), then morale is given to the monster (or taken from the player). If the player immediately steps forward to face the threat, then morale is awarded to the player's character.

Certainly, this is better suited for sporadic one-on-one encounters than in situations with multiple, simultaneous attacks. But there are probably ways to spin the idea as well.


Adrenalin
One of the body's main responses to fear is the pumping of adrenalin, which has three primary effects: (1) vastly increased strength, (2) numbing of pain, and (3) increased perception and reaction time. It's the first and last effect that make adrenalin particularly fit for being a game feature.

A rush of adrenalin slows one's perception of time. Slow-motion cameras work by taking more pictures-per-second than regular cameras. The increased number of photos allows the perceived scene to be stretched out into a slower progression. Adrenalin does the same thing to the brain. It triggers a flood of chemicals to be released in the brain, thereby allowing it to capture experiences in smaller increments... making those experiences seem longer, slower, so the person can react more quickly.

In a game, imagine if dropping below a particular level of health triggered slow-motion, as well as increased strength and speed. Such a feature would not only offer the player one last chance to avoid death, but would also make those dying moments more intense and more memorable.

improving animations

There's a great (but technical-oriented) article on NaturalMotion's euphoria physics engine over at AI GameDev. You might notice that two of the games using that physics simulator, Backbreaker and GTA: IV, are on my wanted list. I'm anxious to see Star Wars: The Force Unleashed as well, but that one could more easily be a short and shallow game (and Star Wars is easier to spoil than football).

Anyway, the article got me wondering how animations could be made better. I have zero experience in animation or programming, so odds are that my speculation will mean very little (which is why I post this here, and not over on the pros' forum). But sometimes an ignorant outsider can raise the right questions... in the same way young children sometimes amaze educated adults with profound insights. So why not throw some stuff out there on the off-chance that it will help?

Besides, I need a Friday post. ;)


A body as a community of symbiotic member-parts
Perhaps one possibility is to divide up a body into functionally separate, but joined and cooperative parts. Just because a player collectively perceives two arms, two legs, a torso, and a head as one object (a human body) does not mean the game's simulators and animators must focus on them in the same collective way.

As millions of diverse living cells in a body act without consideration of their fellows (self-focused programming) while simultaneously maintaining cooperative/collective value (much like thousands of self-focused, individual persons inadvertently cooperate in a stock market), a dozen or half-dozen parts of an animator's model might operate independently of one another and yet not disrupt the player's focus from the whole model.

There are two downsides that I see. First, it means extra processing, but that is becoming less of an issue as an increasing number of games are shifting resources to physics and A.I (away from the tyrannical graphics). Second, more interactive elements means less predictability for programmers. But this, too, woud become less of a problem over time, as one designer's experimentation becomes the next designer's foundational knowledge.

This is probably not a good example, but let's look at walking. The human body when walking is like a series of connected machines, each one reacting to the movements of another. The ankles allow the feet to pivot forward, back, and (to a lesser extent) sideways. The legs then make up for what balance deficits the feet and ankles can't counter. The back then twists in reaction to the legs and waist, also occasionally bending (vertebrae and ribs stretching or collapsing into each other) to absorb shocks. The arms shift, not just forward and back, but in all directions to act as counter-balances (your arms swing outward when you turn). Finally, the head attempts to remain upright in most circumstances. Each section of the body has its own goal which generally requires attention to only one or two other sections.


Joints: more is better
How often do you see models of humans in games with flat feet? Almost all the time, I'd guess, if not all the time. Now stand up and walk around the room, paying close attention to how your toes are involved in walking. The mere fact that the front of your foot (i.e., your toes, collectively) can bend enables a much smoother motion.

Now look at your hands. Each finger has three joints. Try to pick up a coke can or water bottle while only using your back knuckles, the joints that attach your fingers to your hand. There are two differences between that and normal gripping of the container. First, you obviously have a better grip when allowing all of your knuckles to bend and your fingers to encompass more of the container. The second consequence is that removing knuckles from the equation concentrates pressure on two specific points; the pressure is not as widely and evenly distributed. Especially as we move into a gaming era of more depthful and intuitive interfaces (such as virtual gloves), this considerations like these might prove useful.

Lastly, straigthen your arm back as far as it will go. If it was forced much further, your arm would break. Now imagine if injuries in Madden were actually related to events such as that and were not almost entirely random, as they always seem to have been. I know a lot of players who would be much more accepting of injuries if they actually got to see how the injuries happened (from a T-rated distance, at least).


There's a couple of ideas, anyway.

Partnership of medicine and games

I read an article earlier which referenced the many months of research into biomechanics necessary for the developers of the new Splinter Cell game to achieve semi-realistic, complex character motions. Knowledge of biomechanics is of increasing importance as the industry's bar for animation is raised.

In about a month, one of my little sisters begins an internship with the National Institute of Health as a bioengineering assistant. They'll be using a new MRI technology to study the deteriorating joints of persons with cerebral palsy.

Perhaps much could be gained by a partnership between the medical industry and the game industry in the study of biomechanics. By combining the physiological expertise of medical researchers with the programming expertise of game software developers, it seems both sides could benefit greatly. Game developers might provide medical researchers with improved software and interfaces, while physicians might provide game developers with insights into simulating true biomechanics.