Medical items, improved falldamage, "power on" sounds

Subsurface/Items/Components/ItemComponent.cs

@@ -90,6 +90,13 @@ namespace Subsurface
             set { canBeSelected = value; }
         }
 
+        [HasDefaultValue(false, false)]
+        public bool DeleteOnUse
+        {
+            get;
+            set;
+        }
+
         public Item Item
         {
             get { return item; }

Subsurface/Items/Components/Power/PowerTransfer.cs

@@ -49,8 +49,7 @@ namespace Subsurface.Items.Components
                 {
                     pt.powerLoad += (fullLoad - pt.powerLoad) / inertia;
                     pt.currPowerConsumption += (-fullPower - pt.currPowerConsumption) / inertia;
-                    pt.Item.SendSignal("",
-                        "power", fullPower / Math.Max(fullLoad, 1.0f));
+                    pt.Item.SendSignal("", "power", fullPower / Math.Max(fullLoad, 1.0f));
                     if (-pt.currPowerConsumption > pt.powerLoad * 2.0f) pt.item.Condition = 0.0f;
                 }
             }

Subsurface/Items/Components/Power/Powered.cs

@@ -10,15 +10,19 @@ namespace Subsurface.Items.Components
         //negative values mean that the item is providing power to connected items
         protected float currPowerConsumption;
 
-        //the amount of power available for the item through connected items
+        //current voltage of the item (load / power)
         protected float voltage;
 
-        //the amount of power required for the item to work
+        //the minimum voltage required for the item to work
         protected float minVoltage;
 
         //the maximum amount of power the item can draw from connected items
         protected float powerConsumption;
 
+        private bool powerOnSoundPlayed;
+
+        private static Sound powerOnSound;
+
         [Editable, HasDefaultValue(0.5f, true)]
         public float MinVoltage
         {
@@ -68,14 +72,28 @@ namespace Subsurface.Items.Components
         public override void Update(float deltaTime, Camera cam)
         {
             if (currPowerConsumption == 0.0f) return;
-            if (voltage > minVoltage) ApplyStatusEffects(ActionType.OnActive, deltaTime);
+            if (voltage > minVoltage)
+            {
+                if (!powerOnSoundPlayed)
+                {
+                    powerOnSound.Play(1.0f, 600.0f, item.Position);
+                    powerOnSoundPlayed = true;
+                }
+                ApplyStatusEffects(ActionType.OnActive, deltaTime);
+            }
+            else if (voltage < 0.1f)            
+            {
+                powerOnSoundPlayed = false;
+            }
         }
 
         public Powered(Item item, XElement element)
             : base(item, element)
         {
-            //minVoltage = ToolBox.GetAttributeFloat(element, "minvoltage", 10.0f);
-            //powerConsumption = ToolBox.GetAttributeFloat(element, "powerconsumption", 15.0f);
+            if (powerOnSound==null)
+            {
+                powerOnSound = Sound.Load("Content/Items/Electricity/powerOn.ogg");
+            }
         }
     }
 }