Added Camera centerOnX and centerOnY methods.

Author: photonstorm

CHANGELOG.md

@@ -73,6 +73,8 @@
 * `Geom.Line.GetNearestPoint` is a new static method that will return the nearest point on a line to the given point.
 * `Geom.Line.GetShortestDistance` is a new static method that will return the shortest distance from a line to the given point.
 * `Camera.getBounds` is a new method that will return a rectangle containing the bounds of the camera.
+* `Camera.centerOnX` will move the camera horizontally to be centered on the given coordinate, without changing its vertical placement.
+* `Camera.centerOnY` will move the camera vertically to be centered on the given coordinate, without changing its horizontally placement.
 
 ### Updates
 

src/cameras/2d/BaseCamera.js

@@ -590,35 +590,78 @@ var BaseCamera = new Class({
     },
 
     /**
-     * Moves the Camera so that it is centered on the given coordinates, bounds allowing.
+     * Moves the Camera horizontally so that it is centered on the given x coordinate, bounds allowing.
+     * Calling this does not change the scrollY value.
      *
-     * @method Phaser.Cameras.Scene2D.BaseCamera#centerOn
-     * @since 3.11.0
+     * @method Phaser.Cameras.Scene2D.BaseCamera#centerOnX
+     * @since 3.16.0
      *
      * @param {number} x - The horizontal coordinate to center on.
-     * @param {number} y - The vertical coordinate to center on.
      *
      * @return {Phaser.Cameras.Scene2D.BaseCamera} This Camera instance.
      */
-    centerOn: function (x, y)
+    centerOnX: function (x)
     {
         var originX = this.width * 0.5;
-        var originY = this.height * 0.5;
 
-        this.midPoint.set(x, y);
+        this.midPoint.x = x;
 
         this.scrollX = x - originX;
-        this.scrollY = y - originY;
 
         if (this.useBounds)
         {
             this.scrollX = this.clampX(this.scrollX);
+        }
+
+        return this;
+    },
+
+    /**
+     * Moves the Camera vertically so that it is centered on the given y coordinate, bounds allowing.
+     * Calling this does not change the scrollX value.
+     *
+     * @method Phaser.Cameras.Scene2D.BaseCamera#centerOnY
+     * @since 3.16.0
+     *
+     * @param {number} y - The vertical coordinate to center on.
+     *
+     * @return {Phaser.Cameras.Scene2D.BaseCamera} This Camera instance.
+     */
+    centerOnY: function (y)
+    {
+        var originY = this.height * 0.5;
+
+        this.midPoint.y = y;
+
+        this.scrollY = y - originY;
+
+        if (this.useBounds)
+        {
             this.scrollY = this.clampY(this.scrollY);
         }
 
         return this;
     },
 
+    /**
+     * Moves the Camera so that it is centered on the given coordinates, bounds allowing.
+     *
+     * @method Phaser.Cameras.Scene2D.BaseCamera#centerOn
+     * @since 3.11.0
+     *
+     * @param {number} x - The horizontal coordinate to center on.
+     * @param {number} y - The vertical coordinate to center on.
+     *
+     * @return {Phaser.Cameras.Scene2D.BaseCamera} This Camera instance.
+     */
+    centerOn: function (x, y)
+    {
+        this.centerOnX(x);
+        this.centerOnY(y);
+
+        return this;
+    },
+
     /**
      * Moves the Camera so that it is looking at the center of the Camera Bounds, if enabled.
      *