Merge pull request phaserjs#3727 from samme/feature/camera-centerXY

Add Camera#centerX, Camera#centerY

Author: photonstorm

src/cameras/2d/Camera.js

@@ -1284,6 +1284,40 @@ var Camera = new Class({
         this._bounds = null;
 
         this.scene = null;
+    },
+
+    /**
+     * The x position of the center of the Camera's viewport, relative to the top-left of the game canvas.
+     *
+     * @name Phaser.Cameras.Scene2D.Camera#centerX
+     * @type {number}
+     * @readOnly
+     * @since 3.10.0
+     */
+    centerX: {
+
+        get: function ()
+        {
+            return this.x + (0.5 * this.width);
+        }
+
+    },
+
+    /**
+     * The y position of the center of the Camera's viewport, relative to the top-left of the game canvas.
+     *
+     * @name Phaser.Cameras.Scene2D.Camera#centerY
+     * @type {number}
+     * @readOnly
+     * @since 3.10.0
+     */
+    centerY: {
+
+        get: function ()
+        {
+            return this.y + (0.5 * this.height);
+        }
+
     }
 
 });