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+# Principle
+
+Ever felt frustrated by the limited choice of map settings offered by DCS Liberation ?
+Good news, you can mod your custom campaigns setup in liberation !
+
+Custom campaigns/theaters can be created easily with a text editor as a json file.
+
+You can put your own campaigns configuration json files in the folder **./resources/campaigns**, and restart DCS Liberation to load them.
+If there is no error, your custom campaign will appear in the New game wizard.
+If there is an error, with the file, please check the content of the console output, it might contains hints.
+
+# File format
+
+This json file should contain a json object, with the following parameters :
+
+* **name** : The name of the campaign/theater
+* **theater** : The map for the campaing (Either : "Caucasus", "Persian Gulf", "Nevada", "Normandy", "Syria" or "The Channel" 
+* **player_points** : A list of control points owned by the player by default
+* **enemy_points** : A list of control points owned by the enemy by default
+* **links** : The existing connections between points. A list of connected points (using their id) You shouldn't link points if there is water between them.
+
+Control point object structure in the json file :
+
+* **type** : Either "airbase" for an existing base in DCS, "lha" for helicopter Carriers, or "carrier" for an aircraft carrier.
+* **id** : The name of the airbase (if an airbase), or a number (> 1000) for an aircraft carrier or an lha. (If you have multiple carriers/lhas, make sure they do not share the same ID)
+* **x** : X starting position of the carrier or lha in DCS coordinates (See the last part of this tutorial to see how to retrieve these coordinates from DCS mission editor)
+* **y** : Y starting position of the carrier or lha in DCS coordinates
+* **importance** : Importance of the base for the AI. (1 for low importance, 1.4 for high importance) (airbase only)
+* **size** : Size of the airbase in meter for unit placement. (This is a legacy parameter, that you can ignore and put 1000)
+* **captured_invert** : Whether the control point should be owned by the player if you select "invert map" in new game wizard.
+
+
+**Note :**
+
+*I highly recommend you look at the default file provided in DCS Liberation for examples. There might be other parameters in these files, but you shouldn't change them.*
+
+# Example file
+
+Below is an example of campaign file :
+
+
+```json
+{
+    "name": "Caucasus - Western Georgia",
+    "theater": "Caucasus",
+    "player_points": [
+        {
+            "type": "airbase",
+            "id": "Kobuleti",
+            "size": 600,
+            "importance": 1.1
+        },
+        {
+            "type": "carrier",
+            "id": 1001,
+            "x": -285810.6875,
+            "y": 496399.1875,
+            "captured_invert": true
+        },
+        {
+            "type": "lha",
+            "id": 1002,
+            "x": -326050.6875,
+            "y": 519452.1875,
+            "captured_invert": true
+        }
+    ],
+    "enemy_points": [
+        {
+            "type": "airbase",
+            "id": "Kutaisi",
+            "size": 600,
+            "importance": 1
+        },
+        {
+            "type": "airbase",
+            "id": "Senaki-Kolkhi",
+            "size": 1000,
+            "importance": 1
+        },
+        {
+            "type": "airbase",
+            "id": "Sukhumi-Babushara",
+            "size": 1000,
+            "importance": 1.2
+        },
+        {
+            "type": "airbase",
+            "id": "Gudauta",
+            "size": 1000,
+            "importance": 1.2
+        },
+        {
+            "type": "airbase",
+            "id": "Sochi-Adler",
+            "size": 2000,
+            "importance": 1.4,
+            "captured_invert": true
+        }
+    ],
+    "links": [
+        [
+            "Kutaisi",
+            "Senaki-Kolkhi"
+        ],
+        [
+            "Kobuleti",
+            "Senaki-Kolkhi"
+        ],
+        [
+            "Senaki-Kolkhi",
+            "Sukhumi-Babushara"
+        ],
+        [
+            "Gudauta",
+            "Sukhumi-Babushara"
+        ],
+        [
+            "Gudauta",
+            "Sochi-Adler"
+        ]
+    ]
+}
+```
+
+# Annex : Retrieving X/Y coordinates from DCS Mission Editor :
+
+* **Step 0 :** Open DCS ME, with the map you are using
+* **Step 1 :** Place the carrier where you want it to be located
+
+* **Step 2:** Keep the mouse cursor on the carrier, and press ```right-alt+y``` multiple time, until DCS changes to X/Y coords scheme. Copy these coordinates in your campaign json file ! (Do not forget the sign, often coordinates can be negative)
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