Infinite Voyager: Adaptive Difficulty in Space Combat

AI Director Update Loop (Every 5 seconds)

The Director runs a tight evaluation cycle, reading player state and adjusting difficulty multipliers:

function updateDirector(playerState, gameState) {
  const dodgeRate = playerState.obstaclesDodged / playerState.obstaclesEncountered;
  const coinEfficiency = playerState.coinsCollected / playerState.coinsAvailable;
  const recentDeaths = playerState.deathsInLast60s;

  // Spawn rate adjustment
  let spawnMultiplier = 1.0;
  if (dodgeRate > 0.8) spawnMultiplier += 0.3;      // Dominating
  else if (dodgeRate < 0.3) spawnMultiplier -= 0.3; // Struggling

  // Accuracy adjustment
  let accuracyMultiplier = 1.0;
  if (dodgeRate > 0.8) accuracyMultiplier = 1.0;   // Full difficulty
  else if (dodgeRate < 0.3) accuracyMultiplier = 0.5; // Half difficulty

  // Stealth Assist: after 3 deaths in 60s
  if (recentDeaths >= 3) {
    accuracyMultiplier *= 0.5;
    stealthAssistActive = true;
    stealthAssistTimer = 30;
  }

  // Power-up Boost when survival < 15s
  let powerUpMultiplier = 1.0;
  if (playerState.survivalTime < 15) {
    powerUpMultiplier = 1.4;
  }

  return {spawnMultiplier, accuracyMultiplier, powerUpMultiplier};
}

This creates a feedback loop: performance → difficulty → challenge → motivation. Players always face the "right" difficulty.

Enemy Behavior: Alien Types

Each of the 4 enemy types has distinct behavioral logic:

// Scout: Weaving side-to-side
function moveScout(scout, time) {
  scout.x += Math.sin(time * 2) * 120 * deltaTime;
}

// Drone: Tracks player, fires every 3s
function moveDrone(drone, playerX) {
  drone.x = lerp(drone.x, playerX, 0.1);
  if ((gameTime % 3000) < 100) spawnBolt(drone);
}

// Mothership: Spawns scouts every 8s (max 12)
function moveMotherShip(ship) {
  if ((gameTime % 8000) < 100 && ship.scouts.length < 12) {
    ship.scouts.push(new Scout());
  }
}

// Phantom: Mirrors player X, cloaks 2s every 4s
function movePhantom(phantom, playerX, time) {
  phantom.x = playerX;
  phantom.cloaked = (Math.floor(time / 4) % 2 === 1);
}

Behavior variety forces tactical adaptation. Players can't use the same strategy for all enemies.

Procedural Visuals: Star Field & Parallax

The background uses positional seeding (not Perlin noise) for deterministic star placement:

Each screen position generates the same stars consistently. Multiple depth layers with different scroll speeds create parallax depth. Velocity-based speed lines enhance the sense of forward motion.

Encounter System: Timing & Variety

Encounters spawn every 45–90 seconds with four types:

• Wormhole — Teleports player +200m, triggers enemy spawn cluster
• Distress Signal — Protect NPC ship for 10s, earn 150 coins
• Solar Flare — 8s of 2x thrust + 50% alien slowdown
• Alien Market — Rotating station for purchasing upgrades

Encounter selection is probabilistic but weighted by level phase. Campaign phases naturally introduce encounters that suit progression.

Boss Fight State Machines

Three unique boss types at campaign milestones:

Each boss teaches a lesson: learn attack patterns, adapt to role reversals, manage clones. Boss fights act as skill gates for progression.

Difficulty Scaling Formula

The ultimate spawn interval combines base level difficulty with real-time Director adjustments:

diffMultiplier increases with campaign level (harder late-game). directorMultiplier adjusts based on performance. Result: enemies spawn more frequently and accurately as you prove competence, creating smooth progression curves without artificial walls.

Backend: Convex Integration

Campaign progress, leaderboard scores, and achievement tracking sync through Convex. Players can resume campaigns mid-level. Session logging enables post-mortem analytics: which encounters killed players most? Which boss has the highest skip rate? Data drives balance updates.