Allow objects to be triggered only once.

Author: daid

src/triggerableNode.cpp

@@ -2,19 +2,26 @@
 
 void TriggerableNode::triggerAdd()
 {
+    if (once && trigger_counter)
+        return;
     if (!trigger_counter)
         onTrigger();
     trigger_counter++;
 }
 
 void TriggerableNode::triggerSubstract()
 {
+    if (once)
+        return;
     trigger_counter--;
     if (!trigger_counter)
         onUnTrigger();
 }
 
 void TriggerableNode::setProperty(sp::string name, sp::string value)
 {
-    LevelObject::setProperty(name, value);
+    if (name == "trigger_once")
+        once = sp::stringutil::convert::toBool(value);
+    else
+        LevelObject::setProperty(name, value);
 }

src/triggerableNode.h

@@ -25,6 +25,7 @@ class TriggerableNode : public LevelObject
 private:
     int trigger_counter = 0;
     sp::string trigger_name;
+    bool once = false;
 };
 
 #endif//TRIGGER_H