Initial IME support

Author: Voltstro

src/Packages/UnityWebBrowser/Runtime/Core/RawImageUwbClientInputHandler.cs

@@ -93,6 +93,21 @@ protected override void OnStart()
             base.OnStart();
             if (inputHandler == null)
                 throw new NullReferenceException("The input handler is null! You need to assign it in the editor!");
+            
+            browserClient.OnInputFocus += OnClientInput;
+        }
+
+        private void OnClientInput(bool focused)
+        {
+            if (focused)
+            {
+                if (!GetMousePosition(out Vector2 pos)) return;
+                pos.x /= 1.5f;
+                inputHandler.EnableIme(pos);
+                return;
+            }
+            
+            inputHandler.DisableIme();
         }
 
         protected override void OnDestroyed()

src/Packages/UnityWebBrowser/Runtime/Core/WebBrowserClient.cs

@@ -628,6 +628,13 @@ internal void InvokeOnPopup(WebBrowserPopupInfo popupInfo)
             OnPopup?.Invoke(popupInfo);
         }
 
+        public event OnInputFocus OnInputFocus;
+
+        internal void InvokeOnInputFocus(bool focused)
+        {
+            OnInputFocus?.Invoke(focused);
+        }
+
         #endregion
 
         #region Browser Controls

src/Packages/UnityWebBrowser/Runtime/Core/WebBrowserCommunicationsManager.cs

@@ -254,6 +254,11 @@ public void Fullscreen(bool fullScreen)
             ExecuteOnUnity(() => client.InvokeFullscreen(fullScreen));
         }
 
+        public void InputFocusChange(bool focused)
+        {
+            ExecuteOnUnity(() => client.InvokeOnInputFocus(focused));
+        }
+
         public void Ready()
         {
             client.EngineReady().Forget();

src/Packages/UnityWebBrowser/Runtime/Events/OnInputFocus.cs

@@ -0,0 +1,9 @@
+// UnityWebBrowser (UWB)
+// Copyright (c) 2021-2023 Voltstro-Studios
+// 
+// This project is under the MIT license. See the LICENSE.md file for more details.
+
+namespace VoltstroStudios.UnityWebBrowser.Events
+{
+    public delegate void OnInputFocus(bool focused);
+}

src/Packages/UnityWebBrowser/Runtime/Events/OnInputFocus.cs.meta

@@ -63,6 +63,16 @@ public abstract class WebBrowserInputHandler : ScriptableObject
         /// </summary>
         public abstract void OnStop();
 
+        /// <summary>
+        ///     Called when IME needs to be enabled
+        /// </summary>
+        public abstract void EnableIme(Vector2 location);
+
+        /// <summary>
+        ///     Called when IME is no longer needed
+        /// </summary>
+        public abstract void DisableIme();
+
         #endregion
     }
 }

src/Packages/UnityWebBrowser/Runtime/Input/WebBrowserInputHandler.cs

@@ -31,6 +31,7 @@ public sealed class WebBrowserInputSystemHandler : WebBrowserInputHandler
         private string inputBuffer = string.Empty;
 
         private Keyboard keyboard;
+        private IMECompositionMode compositionMode;
 
         public override float GetScroll()
         {
@@ -124,6 +125,33 @@ public override void OnStop()
             scrollInput.Disable();
             pointPosition.Disable();
         }
+
+        public override void EnableIme(Vector2 location)
+        {
+            //Appears we still have to set UnityEngine.Input.imeCompositionMode?
+            compositionMode = UnityEngine.Input.imeCompositionMode;
+            UnityEngine.Input.imeCompositionMode = IMECompositionMode.On;
+            
+            keyboard.SetIMEEnabled(true);
+            keyboard.SetIMECursorPosition(location);
+        }
+
+        public override void DisableIme()
+        {
+            UnityEngine.Input.imeCompositionMode = compositionMode;
+            switch (compositionMode)
+            {
+                case IMECompositionMode.Auto:
+                case IMECompositionMode.On:
+                    keyboard.SetIMEEnabled(true);
+                    break;
+                case IMECompositionMode.Off:
+                    keyboard.SetIMEEnabled(false);
+                    break;
+                default:
+                    throw new ArgumentOutOfRangeException();
+            }
+        }
     }
 }
 

src/Packages/UnityWebBrowser/Runtime/Input/WebBrowserInputSystemHandler.cs

@@ -33,6 +33,8 @@ public sealed class WebBrowserOldInputHandler : WebBrowserInputHandler
         private readonly List<WindowsKey> keysDown = new();
         private readonly List<WindowsKey> keysUp = new();
 
+        private IMECompositionMode compositionMode;
+
         public override float GetScroll()
         {
             return UnityEngine.Input.GetAxis(scrollAxisName) * scrollSensitivity;
@@ -107,5 +109,17 @@ public override void OnStart()
         public override void OnStop()
         {
         }
+
+        public override void EnableIme(Vector2 location)
+        {
+            compositionMode = UnityEngine.Input.imeCompositionMode;
+            UnityEngine.Input.imeCompositionMode = IMECompositionMode.On;
+            UnityEngine.Input.compositionCursorPos = location;
+        }
+
+        public override void DisableIme()
+        {
+            UnityEngine.Input.imeCompositionMode = compositionMode;
+        }
     }
 }

src/Packages/UnityWebBrowser/Runtime/Input/WebBrowserOldInputHandler.cs

@@ -41,7 +41,7 @@ public UwbCefClient(CefSize size, PopupAction popupAction, EnginePopupManager po
 
         //Setup our handlers
         loadHandler = new UwbCefLoadHandler(this);
-        renderHandler = new UwbCefRenderHandler(size);
+        renderHandler = new UwbCefRenderHandler(this, size);
         lifespanHandler = new UwbCefLifespanHandler(popupAction, popupManager, proxySettings);
         lifespanHandler.AfterCreated += cefBrowser =>
         {

src/UnityWebBrowser.Engine.Cef/Browser/UwbCefClient.cs

@@ -7,6 +7,8 @@
 using System.Numerics;
 using System.Runtime.InteropServices;
 using System.Security;
+using UnityWebBrowser.Engine.Cef.Core;
+using VoltstroStudios.UnityWebBrowser.Engine.Shared.Core;
 using Xilium.CefGlue;
 
 namespace UnityWebBrowser.Engine.Cef.Browser;
@@ -19,16 +21,19 @@ public class UwbCefRenderHandler : CefRenderHandler
     private readonly object pixelsLock;
     private CefSize cefSize;
     private byte[] pixels;
+
+    private readonly ClientControlsActions clientControls;
 
     /// <summary>
     ///     Tracked mouse scroll position
     /// </summary>
     public Vector2 MouseScrollPosition { get; private set; }
 
-    public UwbCefRenderHandler(CefSize size)
+    public UwbCefRenderHandler(UwbCefClient client, CefSize size)
     {
         pixelsLock = new object();
         Resize(size);
+        clientControls = client.ClientControls;
     }
 
     public byte[] Pixels
@@ -114,4 +119,10 @@ protected override void OnImeCompositionRangeChanged(CefBrowser browser, CefRang
         CefRectangle[] characterBounds)
     {
     }
+
+    protected override void OnVirtualKeyboardRequested(CefBrowser browser, CefTextInputMode inputMode)
+    {
+        CefLoggerWrapper.Debug($"Input mode changed to: {inputMode}");
+        clientControls.InputFocusChange(inputMode == CefTextInputMode.Default);
+    }
 }