Technology · Bodies
Characters with a body, not just an animation.
Characters in Arcwright have a skeleton with muscles that keeps its balance, hitboxes fitted to its own shape, clothes cut to its measurements, and hands that hold things by the grip. When they're hit, they react like a body would.
123456- 1Balance point: the body's centre of mass.
- 2The balance line straight down to the floor. Outside the feet, it has to step or fall.
- 3The skeleton: every bone the engine moves.
- 4Hitboxes, fitted to this body's own shape.
- 5The body mesh, drawn as wire.
- 6Feet on the floor.
- The bodyOur own body models
- SkeletonA rig on every character
- Muscles and balanceIt fights to stay up
- HitboxesFitted to its shape
- Clothes and gearCut to its measurements
- HandsGrip things by the grip
- ReactionsBuckle, catch, get back up
01 · The body
Built for close-ups.
Our own body models are built clean down to the knuckles and the eyelids, so a hand can close round a grip and a face can move without tearing. Bodies come in different builds, from slim to muscular to older and heavier.
A finished face from the Face Forger, on our body model.
A hand, in wireframe.
A head, in wireframe.
An older, heavier build.
02 · Faces
Eyes that catch the light.
Eyes have a cornea that catches the light, an iris under it and wet edges. Even a zombie's dead eyes read as eyes.
03 · Balance
Every body fights to stay on its feet.
Every character carries a balance point. When it leaves the space between the feet, the body has to step, or it falls. Walk a zombie into a post and it steps, steps again, fights to stay up, loses, and starts pushing itself back up.
04 · Falling
Hands out to catch the fall.
A shot body used to go limp the instant it was hit. Now it buckles, the hands go out to catch the fall, and the muscles let go one limb at a time.
05 · Shots
Each body reacts where it was hit.
Hit in the body, a zombie reaches for the wound and staggers; the third shot drops it. Hit in the leg, it buckles on that side. The red line is the bullet's path, white at the muzzle, with a red dot where it hit.
06 · Getting up
Down isn't the end.
A fallen character rolls over, gets its hands planted and its knees under it, and stands back up.
07 · Hitboxes
Bullets hit what you aimed at.
Our first hitboxes covered only 33 to 44 percent of each character: a zombie in a big jacket is much wider than the shape under it, and the hands had none. Now every character's hitboxes are fitted to its own body, clothes and all: 85 percent coverage, plus the hands and the neck.
Fitted hitboxes in wire, from two angles.
A fall test: skeleton, balance line and the shot.
08 · Clothes and gear
Cut to the body, never through it.
Clothes are tailored: drafted from the body's measurements as real sewing patterns, sewn and draped on the character, then made to move with it. Gear like boots, belts, a plate carrier and pouches sits over the clothes, at a distance you can set.
Whatever the clothes and gear cover is hidden on the body underneath, automatically, so a knee can't poke through a boot when it bends.
The plate carrier over the uniform.
Boots, laced, over the trousers.
09 · Hands
Things are held by the grip.
Hands open, relax or make a fist, per hand, and a fist closes round a sword grip. A prop goes in the hand by its grip, so a gun or a sword sits where it should. Reloads are done by hand: the magazine comes out, a fresh one goes in, and a pistol's slide locks open on its last round.
The full story of the reactions system is in the devlog: Teaching zombies to stay on their feet.
See it for yourself.
Download Arcwright free and open any of our games to see these systems at work.
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