controls

Controls (player-visible signs — do not ship inverted)

Read this end-to-end before writing movement/steer/flight code for any game that uses WASD, arrows, a chase camera, or a flying craft. Do not skip this and only open racing-kart or fps — those genre files assume you already know these signs. Inverted A/D is the most common ship-blocker in vehicle and flight demos.

Pair with building-games (loop, camera, 3D orientation) and building-games/references/input.md (keydown state, gamepad, touch). This skill owns what left/right/up mean to the player and how you prove it.

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0. Hard rules (fail the build if broken)

1. Player-visible left/right is law. From a chase / behind camera while the craft moves forward:
   • A / ← → nose (or bank) turns left on screen
   • D / → → nose (or bank) turns right on screen
2. Never reuse FPS strafe as vehicle steer. FPS “D → +right vector” is position on the ground plane. Vehicle A/D is yaw (or roll) rate, not a strafe offset. Mixing them is the #1 cause of inverted A/D.
3. You must run a control self-test (§5) before saying done. Screenshot-only QA is not enough. If A turns right, flip the steer/roll sign, retest, then ship — do not invent a new coordinate story.

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1. Shared 3D basis (use this everywhere)

three.js: right-handed, +Y up, meshes face +Z, cameras look −Z.

Yaw-only heading on XZ (ground vehicles, walkers, most arcade craft):

// yaw = 0 faces world −Z; +yaw is CCW about +Y (nose moves toward −X)
forward = (-sin(yaw), 0, -cos(yaw))
right   = ( cos(yaw), 0, -sin(yaw))   // = normalize(cross(forward, worldUp))

With a chase cam behind the craft (camera near position - forward * dist):

Player sees	World (this basis)	Input
Nose left	+yaw	A / ← must produce +yaw (or equivalent bank-left for planes)
Nose right	−yaw	D / → must produce −yaw