From 3b8d019b972cdfec8b3ddb35183deb31a7c3c263 Mon Sep 17 00:00:00 2001
From: Rex <binhua.tein@gmail.com>
Date: Sun, 31 Dec 2023 17:11:38 +0800
Subject: [PATCH] Add EXPAND scale mode

---
 src/scale/ScaleManager.js           | 49 ++++++++++++++++++++++++++++-
 src/scale/const/SCALE_MODE_CONST.js | 13 +++++++-
 2 files changed, 60 insertions(+), 2 deletions(-)

diff --git a/src/scale/ScaleManager.js b/src/scale/ScaleManager.js
index c30db4f73..17e4d80ca 100644
--- a/src/scale/ScaleManager.js
+++ b/src/scale/ScaleManager.js
@@ -431,7 +431,7 @@ var ScaleManager = new Class({
 
         this.fullscreen = game.device.fullscreen;
 
-        if (this.scaleMode !== CONST.SCALE_MODE.RESIZE)
+        if ((this.scaleMode !== CONST.SCALE_MODE.RESIZE) && (this.scaleMode !== CONST.SCALE_MODE.EXPAND))
         {
             this.displaySize.setAspectMode(this.scaleMode);
         }
@@ -1047,6 +1047,53 @@ var ScaleManager = new Class({
             this.canvas.width = styleWidth;
             this.canvas.height = styleHeight;
         }
+        else if (this.scaleMode === CONST.SCALE_MODE.EXPAND)
+        {            
+            //  Resize to match parent, like RESIZE mode
+
+            //  This will constrain using min/max
+            this.displaySize.setSize(this.parentSize.width, this.parentSize.height);
+            
+            styleWidth = this.displaySize.width;
+            styleHeight = this.displaySize.height;
+
+            if (autoRound)
+            {
+                styleWidth = Math.floor(styleWidth);
+                styleHeight = Math.floor(styleHeight);
+            }
+
+            style.width = styleWidth + 'px';
+            style.height = styleHeight + 'px';
+
+
+            // Expand canvas size to fit game size's width or height
+
+            var scaleX = this.parentSize.width / this.gameSize.width;
+
+            var scaleY = this.parentSize.height / this.gameSize.height;
+
+            if (scaleX < scaleY) 
+            {
+                this.baseSize.setSize(this.gameSize.width, this.parentSize.height / scaleX);
+            } 
+            else
+            {
+                this.baseSize.setSize(this.displaySize.width / scaleY, this.gameSize.height);
+            }
+
+            styleWidth = this.baseSize.width;
+            styleHeight = this.baseSize.height;
+
+            if (autoRound)
+            {
+                styleWidth = Math.floor(styleWidth);
+                styleHeight = Math.floor(styleHeight);
+            }
+
+            this.canvas.width = styleWidth;
+            this.canvas.height = styleHeight;           
+        }
         else
         {
             //  All other scale modes
diff --git a/src/scale/const/SCALE_MODE_CONST.js b/src/scale/const/SCALE_MODE_CONST.js
index bee58fb8c..6362301a0 100644
--- a/src/scale/const/SCALE_MODE_CONST.js
+++ b/src/scale/const/SCALE_MODE_CONST.js
@@ -87,6 +87,17 @@ module.exports = {
      * @const
      * @since 3.16.0
      */
-    RESIZE: 5
+    RESIZE: 5,
+
+    /**
+     * The Canvas's visible area is resized to fit all available _parent_ space like RESIZE mode,
+     * and scale canvas size to fit inside the visible area like FIT mode.
+     *
+     * @name Phaser.Scale.ScaleModes.EXPAND
+     * @type {number}
+     * @const
+     * @since 3.70.1
+     */
+    EXPAND : 6
 
 };