From 5433e368373adbae9d3ced42d54a768456a2dff0 Mon Sep 17 00:00:00 2001
From: MowfaqAlarbi <54871067+MowfaqAlarbi@users.noreply.github.com>
Date: Fri, 6 Sep 2019 19:13:00 +0200
Subject: [PATCH] Show Node Create list When Dragging To Nothing (#183)

And a user setting to disable it, of course
---
 Scripts/Editor/NodeEditorAction.cs      | 25 +++++++++++++++++++++++++
 Scripts/Editor/NodeEditorPreferences.cs |  2 ++
 Scripts/Editor/NodeGraphEditor.cs       |  8 +++++---
 3 files changed, 32 insertions(+), 3 deletions(-)

diff --git a/Scripts/Editor/NodeEditorAction.cs b/Scripts/Editor/NodeEditorAction.cs
index 1caecd9..cf52351 100644
--- a/Scripts/Editor/NodeEditorAction.cs
+++ b/Scripts/Editor/NodeEditorAction.cs
@@ -22,6 +22,7 @@ namespace XNodeEditor {
         [NonSerialized] private XNode.NodePort hoveredPort = null;
         [NonSerialized] private XNode.NodePort draggedOutput = null;
         [NonSerialized] private XNode.NodePort draggedOutputTarget = null;
+        [NonSerialized] private XNode.NodePort autoConnectOutput = null;
         [NonSerialized] private List<Vector2> draggedOutputReroutes = new List<Vector2>();
         private RerouteReference hoveredReroute = new RerouteReference();
         private List<RerouteReference> selectedReroutes = new List<RerouteReference>();
@@ -145,8 +146,10 @@ namespace XNodeEditor {
                         if (IsHoveringPort) {
                             if (hoveredPort.IsOutput) {
                                 draggedOutput = hoveredPort;
+                                autoConnectOutput = hoveredPort;
                             } else {
                                 hoveredPort.VerifyConnections();
+                                autoConnectOutput = null;
                                 if (hoveredPort.IsConnected) {
                                     XNode.Node node = hoveredPort.node;
                                     XNode.NodePort output = hoveredPort.Connection;
@@ -214,6 +217,12 @@ namespace XNodeEditor {
                                     EditorUtility.SetDirty(graph);
                                 }
                             }
+                            // Open context menu for auto-connection
+                            else if (NodeEditorPreferences.GetSettings().dragToCreate && autoConnectOutput != null) {
+                                GenericMenu menu = new GenericMenu();
+                                graphEditor.AddContextMenuItems(menu);
+                                menu.DropDown(new Rect(Event.current.mousePosition, Vector2.zero));
+                            }
                             //Release dragged connection
                             draggedOutput = null;
                             draggedOutputTarget = null;
@@ -491,5 +500,21 @@ namespace XNodeEditor {
             Rect windowRect = new Rect(nodePos, new Vector2(width / zoom, 30 / zoom));
             return windowRect.Contains(mousePos);
         }
+
+        /// <summary> Attempt to connect dragged output to target node </summary>
+        public void AutoConnect(XNode.Node node) {
+            if (autoConnectOutput == null) return;
+
+            // Find input port of same type
+            XNode.NodePort inputPort = node.Ports.FirstOrDefault(x => x.IsInput && x.ValueType == autoConnectOutput.ValueType);
+            // Fallback to input port
+            if (inputPort == null) inputPort = node.Ports.FirstOrDefault(x => x.IsInput);
+            // Autoconnect
+            if (inputPort != null) autoConnectOutput.Connect(inputPort);
+
+            // Save changes
+            EditorUtility.SetDirty(graph);
+            if (NodeEditorPreferences.GetSettings().autoSave) AssetDatabase.SaveAssets();
+        }
     }
 }
\ No newline at end of file
diff --git a/Scripts/Editor/NodeEditorPreferences.cs b/Scripts/Editor/NodeEditorPreferences.cs
index c28c064..9e9bb64 100644
--- a/Scripts/Editor/NodeEditorPreferences.cs
+++ b/Scripts/Editor/NodeEditorPreferences.cs
@@ -32,6 +32,7 @@ namespace XNodeEditor {
             public Color32 highlightColor = new Color32(255, 255, 255, 255);
             public bool gridSnap = true;
             public bool autoSave = true;
+            public bool dragToCreate = true;
             public bool zoomToMouse = true;
             public bool portTooltips = true;
             [SerializeField] private string typeColorsData = "";
@@ -149,6 +150,7 @@ namespace XNodeEditor {
             settings.highlightColor = EditorGUILayout.ColorField("Selection", settings.highlightColor);
             settings.noodleType = (NoodleType) EditorGUILayout.EnumPopup("Noodle type", (Enum) settings.noodleType);
             settings.portTooltips = EditorGUILayout.Toggle("Port Tooltips", settings.portTooltips);
+            settings.dragToCreate = EditorGUILayout.Toggle(new GUIContent("Drag to Create", "Drag a port connection anywhere on the grid to create and connect a node"), settings.dragToCreate);
             if (GUI.changed) {
                 SavePrefs(key, settings);
                 NodeEditorWindow.RepaintAll();
diff --git a/Scripts/Editor/NodeGraphEditor.cs b/Scripts/Editor/NodeGraphEditor.cs
index a45d566..bdd4fa0 100644
--- a/Scripts/Editor/NodeGraphEditor.cs
+++ b/Scripts/Editor/NodeGraphEditor.cs
@@ -52,7 +52,8 @@ namespace XNodeEditor {
                 if (string.IsNullOrEmpty(path)) continue;
 
                 menu.AddItem(new GUIContent(path), false, () => {
-                    CreateNode(type, pos);
+                    XNode.Node node = CreateNode(type, pos);
+                    NodeEditorWindow.current.AutoConnect(node);
                 });
             }
             menu.AddSeparator("");
@@ -87,13 +88,14 @@ namespace XNodeEditor {
         }
 
         /// <summary> Create a node and save it in the graph asset </summary>
-        public virtual void CreateNode(Type type, Vector2 position) {
+        public virtual XNode.Node CreateNode(Type type, Vector2 position) {
             XNode.Node node = target.AddNode(type);
             node.position = position;
             if (node.name == null || node.name.Trim() == "") node.name = NodeEditorUtilities.NodeDefaultName(type);
             AssetDatabase.AddObjectToAsset(node, target);
             if (NodeEditorPreferences.GetSettings().autoSave) AssetDatabase.SaveAssets();
             NodeEditorWindow.RepaintAll();
+            return node;
         }
 
         /// <summary> Creates a copy of the original node in the graph </summary>
@@ -114,7 +116,7 @@ namespace XNodeEditor {
 
         [AttributeUsage(AttributeTargets.Class)]
         public class CustomNodeGraphEditorAttribute : Attribute,
-            XNodeEditor.Internal.NodeEditorBase<NodeGraphEditor, NodeGraphEditor.CustomNodeGraphEditorAttribute, XNode.NodeGraph>.INodeEditorAttrib {
+        XNodeEditor.Internal.NodeEditorBase<NodeGraphEditor, NodeGraphEditor.CustomNodeGraphEditorAttribute, XNode.NodeGraph>.INodeEditorAttrib {
             private Type inspectedType;
             public string editorPrefsKey;
             /// <summary> Tells a NodeGraphEditor which Graph type it is an editor for </summary>