feat: living kitties!

common/combat/alive.trait.js

@@ -0,0 +1,57 @@
+import {compose} from '@avocado/core';
+import {StateProperty, Trait} from '@avocado/entity';
+
+const decorate = compose(
+  StateProperty('life', {
+    track: true,
+  }),
+  StateProperty('maxLife', {
+    track: true,
+  }),
+);
+
+export class Alive extends decorate(Trait) {
+
+  static defaultState() {
+    return {
+      life: 100,
+      maxLife: 100,
+    };
+  }
+
+  listeners() {
+    return {
+
+      tookDamage: (damage) => {
+        this.entity.life -= damage.amount;
+        // Clamp health between 0 and max.
+        this.entity.life = Math.min(
+          Math.max(0, this.entity.life),
+          this.entity.maxLife
+        );
+      },
+
+    }
+  }
+
+  tick(elapsed) {
+    // ded
+    // @todo Custom death conditions.
+    if (this.entity.life <= 0) {
+      const allowDeath = this.entity.invokeHookFlat('allowDeath');
+      const overrides = allowDeath.filter((response) => {
+        return false === response;
+      });
+      // Something saved the day.
+      if (overrides.length > 0) {
+
+      }
+      else {
+        // It's a good day to die.
+        this.entity.destroy();
+      }
+    }
+  }
+
+}
+

common/combat/emitter.js

@@ -73,6 +73,10 @@ export class DamageEmitter {
     this.emitter.createParticle(initializers, behaviors);
   }
 
+  hasParticles() {
+    return this.emitter.particles.length > 0;
+  }
+
   tick(elapsed) {
     this.proton.tick(elapsed);
   }

common/combat/vulnerable.trait.js

@@ -50,6 +50,22 @@ export class Vulnerable extends Trait {
     }
   }
 
+  hooks() {
+    return {
+
+      afterDestructionTickers: () => {
+        return (elapsed) => {
+          if (!hasGraphics) {
+            return true;
+          }
+          this.emitter.tick(elapsed);
+          return !this.emitter.hasParticles();
+        };
+      },
+
+    }
+  }
+
   listeners() {
     return {
 
@@ -92,12 +108,14 @@ export class Vulnerable extends Trait {
           if (!this.damageList[entity.instanceUuid]) {
             this.damageList[entity.instanceUuid] = [];
           }
-          this.damageList[entity.instanceUuid].push({
+          const damage = {
             id: this.damageId++,
             isDamage,
             amount,
             damageSpec,
-          });
+          };
+          this.damageList[entity.instanceUuid].push(damage);
+          this.entity.emit('tookDamage', damage);
         }
       },
 
@@ -105,6 +123,9 @@ export class Vulnerable extends Trait {
   }
 
   tick(elapsed) {
+    if (hasGraphics) {
+      this.emitter.tick(elapsed);
+    }
     if (this.state.get('damageList').size > 0) {
       this.state = this.state.set('damageList', I.Map());
     }
@@ -113,9 +134,6 @@ export class Vulnerable extends Trait {
       this.isDirty = true;
       this.damageList = {};
     }
-    if (hasGraphics) {
-      this.emitter.tick(elapsed);
-    }
     const keys = Array.from(this.locks.keys());
     for (let i = 0; i < keys.length; ++i) {
       const key = keys[i];

server/create-server-room.js

@@ -127,6 +127,7 @@ function kittyJSON(position) {
   }
   return {
     traits: {
+      alive: {},
       animated: {
         params: {
           animations: {