feat: add ants with stomp-crush and collision heart damage

js/game.js

@@ -25,6 +25,13 @@ const state = {
   stepCarry: 0,
   cameraX: 0,
   hearts: 3,
+  hitCooldown: 0,
+  ants: [
+    { x: 1000, y: groundY - 20, width: 22, height: 20, vx: -65, alive: true },
+    { x: 1750, y: groundY - 20, width: 22, height: 20, vx: -70, alive: true },
+    { x: 2600, y: groundY - 20, width: 22, height: 20, vx: -80, alive: true },
+    { x: 3400, y: groundY - 20, width: 22, height: 20, vx: -75, alive: true }
+  ],
   player: {
     x: 160,
     y: 0,
@@ -79,6 +86,22 @@ function drawTRex(p) {
   ctx.fillRect(sx + p.width - 24, p.y + p.height - 8, 14, 8);
 }
 
+function drawAnts() {
+  ctx.fillStyle = '#5a1e0d';
+  for (const ant of state.ants) {
+    if (!ant.alive) continue;
+    const sx = ant.x - state.cameraX;
+    if (sx + ant.width < 0 || sx > canvas.width) continue;
+    ctx.fillRect(sx, ant.y, ant.width, ant.height);
+    ctx.fillRect(sx - 4, ant.y + 6, 4, 4);
+    ctx.fillRect(sx + ant.width, ant.y + 6, 4, 4);
+  }
+}
+
+function intersects(a, b) {
+  return a.x < b.x + b.width && a.x + a.width > b.x && a.y < b.y + b.height && a.y + a.height > b.y;
+}
+
 function updateHeartsUI() {
   heartsEl.textContent = '❤'.repeat(state.hearts) + '🖤'.repeat(Math.max(0, 3 - state.hearts));
 }
@@ -89,11 +112,44 @@ function kill(reason) {
   state.deadReason = reason;
 }
 
+function applyHit(reason) {
+  if (state.hitCooldown > 0 || state.dead) return;
+  state.hearts -= 1;
+  state.hitCooldown = 1.0;
+  if (state.hearts <= 0) {
+    kill(reason);
+  }
+}
+
 function isOverWater(player) {
   const centerX = player.x + player.width / 2;
   return waterGaps.some((g) => centerX >= g.x && centerX <= g.x + g.width);
 }
 
+function updateAnts(dt) {
+  const p = state.player;
+  const prevBottom = p.y + p.height - p.vy * dt;
+
+  for (const ant of state.ants) {
+    if (!ant.alive) continue;
+
+    ant.x += ant.vx * dt;
+    if (ant.x < 200) ant.vx = Math.abs(ant.vx);
+    if (ant.x > worldWidth - 200) ant.vx = -Math.abs(ant.vx);
+
+    if (intersects(p, ant)) {
+      const playerBottom = p.y + p.height;
+      const stomped = p.vy > 0 && prevBottom <= ant.y + 4 && playerBottom >= ant.y;
+      if (stomped) {
+        ant.alive = false;
+        p.vy = -380;
+      } else {
+        applyHit('A swarm of ants got you.');
+      }
+    }
+  }
+}
+
 function updatePlayer(dt) {
   const p = state.player;
   let move = 0;
@@ -153,10 +209,15 @@ function tick(ts) {
   const dt = Math.min((ts - state.lastTs) / 1000, 0.05);
   state.lastTs = ts;
 
-  if (state.running) updatePlayer(dt);
+  if (state.running) {
+    state.hitCooldown = Math.max(0, state.hitCooldown - dt);
+    updatePlayer(dt);
+    updateAnts(dt);
+  }
 
   ctx.clearRect(0, 0, canvas.width, canvas.height);
   drawBackground();
+  drawAnts();
   drawTRex(state.player);
   drawDeathText();