From ad29dd0c929aa76b949b0bbb1dc6281372eaee0f Mon Sep 17 00:00:00 2001
From: Luke Schneider <luke@radiangames.com>
Date: Thu, 21 Sep 2023 08:37:13 -0500
Subject: [PATCH] MMB Panning

Added MMB panning to VisjectSurfaces (materials/etc).
---
 Source/Editor/Surface/VisjectSurface.Input.cs | 35 ++++++++++++++++++-
 Source/Editor/Surface/VisjectSurface.cs       | 10 ++++++
 2 files changed, 44 insertions(+), 1 deletion(-)

diff --git a/Source/Editor/Surface/VisjectSurface.Input.cs b/Source/Editor/Surface/VisjectSurface.Input.cs
index 7264321c3..517040cb7 100644
--- a/Source/Editor/Surface/VisjectSurface.Input.cs
+++ b/Source/Editor/Surface/VisjectSurface.Input.cs
@@ -213,6 +213,21 @@ namespace FlaxEditor.Surface
                 return;
             }
 
+            if (_middleMouseDown) {
+                // Calculate delta
+                var delta = location - _middleMouseDownPos;
+                if (delta.LengthSquared > 0.01f) {
+                    // Move view
+                    _mouseMoveAmount += delta.Length;
+                    _rootControl.Location += delta;
+                    _middleMouseDownPos = location;
+                    Cursor = CursorType.SizeAll;
+                }
+
+                // Handled
+                return;
+            }
+
             // Check if user is selecting or moving node(s)
             if (_leftMouseDown)
             {
@@ -269,6 +284,10 @@ namespace FlaxEditor.Surface
                 _rightMouseDown = false;
                 Cursor = CursorType.Default;
             }
+            if (_middleMouseDown) {
+                _middleMouseDown = false;
+                Cursor = CursorType.Default;
+            }
             _isMovingSelection = false;
             ConnectingEnd(null);
 
@@ -380,6 +399,7 @@ namespace FlaxEditor.Surface
                 _isMovingSelection = false;
                 _rightMouseDown = false;
                 _leftMouseDown = false;
+                _middleMouseDown = false;
                 return true;
             }
 
@@ -398,6 +418,12 @@ namespace FlaxEditor.Surface
             {
                 _rightMouseDown = true;
                 _rightMouseDownPos = location;
+                Debug.Log("The right mouse button is down in a window");
+            }
+            if (button == MouseButton.Middle) {
+                _middleMouseDown = true;
+                _middleMouseDownPos = location;
+                Debug.Log("The middle mouse button is down in a window");
             }
 
             // Check if any node is under the mouse
@@ -444,7 +470,7 @@ namespace FlaxEditor.Surface
                     Focus();
                     return true;
                 }
-                if (_rightMouseDown)
+                if (_rightMouseDown || _middleMouseDown)
                 {
                     // Start navigating
                     StartMouseCapture();
@@ -513,6 +539,12 @@ namespace FlaxEditor.Surface
                 }
                 _mouseMoveAmount = 0;
             }
+            if (_middleMouseDown && button == MouseButton.Middle) {
+                _middleMouseDown = false;
+                EndMouseCapture();
+                Cursor = CursorType.Default;
+                _mouseMoveAmount = 0;
+            }
 
             // Base
             bool handled = base.OnMouseUp(location, button);
@@ -523,6 +555,7 @@ namespace FlaxEditor.Surface
                 // Clear flags
                 _rightMouseDown = false;
                 _leftMouseDown = false;
+                _middleMouseDown = false;
                 return true;
             }
 
diff --git a/Source/Editor/Surface/VisjectSurface.cs b/Source/Editor/Surface/VisjectSurface.cs
index 22aba4855..29dbeb1c6 100644
--- a/Source/Editor/Surface/VisjectSurface.cs
+++ b/Source/Editor/Surface/VisjectSurface.cs
@@ -59,6 +59,11 @@ namespace FlaxEditor.Surface
         /// </summary>
         protected bool _rightMouseDown;
 
+        /// <summary>
+        /// The middle mouse down flag.
+        /// </summary>
+        protected bool _middleMouseDown;
+
         /// <summary>
         /// The left mouse down position.
         /// </summary>
@@ -69,6 +74,11 @@ namespace FlaxEditor.Surface
         /// </summary>
         protected Float2 _rightMouseDownPos = Float2.Minimum;
 
+        /// <summary>
+        /// The middle mouse down position.
+        /// </summary>
+        protected Float2 _middleMouseDownPos = Float2.Minimum;
+
         /// <summary>
         /// The mouse position.
         /// </summary>