Updated tutorial_input_events (markdown)

tutorial_input_events.md

@@ -27,7 +27,7 @@ Example of changing event type.
 
 ```python
 # create event
-var ev = InputEvent.new()
+var ev = InputEvent()
 # set type index
 ev.type=InputEvent.MOUSE_BUTTON
 # button_index is only available for the above type
@@ -49,10 +49,28 @@ There are several types of InputEvent, described in the table below:
 |[InputEventAction](class_inputeventaction)|SCREEN_ACTION|Contains a generic action. These events are often generated by the programmer as feedback. (more on this below)|
 
 
+### Actions
+
+An InputEvent may or may not represent a pre-defined action. Actions are useful because they abstract the input device when programming the game logic. This allows for:
+
+* The same code to work on different devices with different inputs (ie: keyboard on PC, Joypad on console)
+* Input to be reconfigured at run-time.
+
+Actions can be created from the Project Settings menu in the Actions tab. If you read the [2D Game Tutorial](tutorial_2d), there is an explanation on how does the action editor work.
+
+Any event has the methods [InputEvent.is_action()](class_inputevent#is_action), [InputEvent.is_pressed()](class_inputevent#is_pressed) amd [InputEvent.is_echo()](class_inputevent#is_echo).
+
+Alternatively, it may be desired to supply the game back with an action from the game code (a good example of this is detecting gestures). SceneTree (derived from MainLoop) has a method for this: [MainLoop.input_event(ev)](class_mainloop#input_event). You would normally use it like this:
+
+```python
+var ev = InputEvent()
+ev.type=InputEvent.ACTION
+#set as move_left, pressed
+ev.set_as_action("move_left",true) 
+#feedback
+get_tree().input_event(ev)
+```
+### InputMap
 
 
-
--explain input event
--explain input editor
--explain as actions
 -explain InputMap and how to map to user-events.