Implement health bar system: add HealthBar class for managing health, integrate health updates in HUDLayer, and modify enemy attack handling to reflect damage taken.

game/enemy/base.rb

@@ -26,9 +26,9 @@ class Enemy
     @w = 25
     @h = 30
     @health = health
-    @lorentz = false
+    @lorentz = $bus.get(:lorentz_field?) || false
 
-    $bus.on(:lorentz_field?) do |lorentz|
+    $bus.on(:lorentz_field!) do |lorentz|
       @lorentz = lorentz
     end
 
@@ -41,9 +41,7 @@ class Enemy
 
   def take_damage(amount)
     @health -= amount
-    pp "Enemy takes #{amount} damage, health now #{@health}"
     if @health <= 0
-      pp "Enemy dies"
       $bus.emit(:enemy_died, self)
     end
   end
@@ -76,6 +74,11 @@ class Enemy
       self.class.frame_size[2]
     )
 
+    # Health bar
+
+    health_width = (@w * @health / 100.0)
+    Gosu.draw_rect(screen_x - @w / 2, screen_y - @h / 2 - 10, health_width, 5, Gosu::Color.new(0xFF00FF00), Float::INFINITY)
+
     if $bus.get(:settings, :debug)
       Gosu.draw_rect(screen_x - @w / 2, screen_y - @h / 2, @w, @h, Gosu::Color.new(0x40FF0000), Float::INFINITY)
     end

game/enemy/force.rb

@@ -6,11 +6,13 @@ class Force < Enemy
   def initialize(x, y)
     super(x, y, 100)
 
-    $bus.on(:occams_razor_attack) do |attack_x, attack_y, range, damage|
+    $bus.on(:attack) do |attack_x, attack_y, range, damage|
       # Whoa, did'nt know ruby had hypot functions built in!
       if Math.hypot(@x - attack_x, @y - attack_y) <= range
         take_damage(damage)
+        next true
       end
+      false
     end
   end
 end