Add similar manual overloads for InputTextMultiline.

src/CodeGenerator/Program.cs

@@ -103,7 +103,8 @@ namespace CodeGenerator
 
         private static readonly HashSet<string> s_skippedFunctions = new HashSet<string>()
         {
-            "igInputText"
+            "igInputText",
+            "igInputTextMultiline"
         };
 
         static void Main(string[] args)

src/ImGui.NET/Generated/ImGui.gen.cs

@@ -3465,112 +3465,6 @@ namespace ImGuiNET
         {
             ImGuiNative.igEndPopup();
         }
-        public static bool InputTextMultiline(string label, string buf, uint buf_size)
-        {
-            int label_byteCount = Encoding.UTF8.GetByteCount(label);
-            byte* native_label = stackalloc byte[label_byteCount + 1];
-            fixed (char* label_ptr = label)
-            {
-                int native_label_offset = Encoding.UTF8.GetBytes(label_ptr, label.Length, native_label, label_byteCount);
-                native_label[native_label_offset] = 0;
-            }
-            int buf_byteCount = Encoding.UTF8.GetByteCount(buf);
-            byte* native_buf = stackalloc byte[buf_byteCount + 1];
-            fixed (char* buf_ptr = buf)
-            {
-                int native_buf_offset = Encoding.UTF8.GetBytes(buf_ptr, buf.Length, native_buf, buf_byteCount);
-                native_buf[native_buf_offset] = 0;
-            }
-            Vector2 size = new Vector2();
-            ImGuiInputTextFlags flags = 0;
-            ImGuiInputTextCallback callback = null;
-            void* user_data = null;
-            byte ret = ImGuiNative.igInputTextMultiline(native_label, native_buf, buf_size, size, flags, callback, user_data);
-            return ret != 0;
-        }
-        public static bool InputTextMultiline(string label, string buf, uint buf_size, Vector2 size)
-        {
-            int label_byteCount = Encoding.UTF8.GetByteCount(label);
-            byte* native_label = stackalloc byte[label_byteCount + 1];
-            fixed (char* label_ptr = label)
-            {
-                int native_label_offset = Encoding.UTF8.GetBytes(label_ptr, label.Length, native_label, label_byteCount);
-                native_label[native_label_offset] = 0;
-            }
-            int buf_byteCount = Encoding.UTF8.GetByteCount(buf);
-            byte* native_buf = stackalloc byte[buf_byteCount + 1];
-            fixed (char* buf_ptr = buf)
-            {
-                int native_buf_offset = Encoding.UTF8.GetBytes(buf_ptr, buf.Length, native_buf, buf_byteCount);
-                native_buf[native_buf_offset] = 0;
-            }
-            ImGuiInputTextFlags flags = 0;
-            ImGuiInputTextCallback callback = null;
-            void* user_data = null;
-            byte ret = ImGuiNative.igInputTextMultiline(native_label, native_buf, buf_size, size, flags, callback, user_data);
-            return ret != 0;
-        }
-        public static bool InputTextMultiline(string label, string buf, uint buf_size, Vector2 size, ImGuiInputTextFlags flags)
-        {
-            int label_byteCount = Encoding.UTF8.GetByteCount(label);
-            byte* native_label = stackalloc byte[label_byteCount + 1];
-            fixed (char* label_ptr = label)
-            {
-                int native_label_offset = Encoding.UTF8.GetBytes(label_ptr, label.Length, native_label, label_byteCount);
-                native_label[native_label_offset] = 0;
-            }
-            int buf_byteCount = Encoding.UTF8.GetByteCount(buf);
-            byte* native_buf = stackalloc byte[buf_byteCount + 1];
-            fixed (char* buf_ptr = buf)
-            {
-                int native_buf_offset = Encoding.UTF8.GetBytes(buf_ptr, buf.Length, native_buf, buf_byteCount);
-                native_buf[native_buf_offset] = 0;
-            }
-            ImGuiInputTextCallback callback = null;
-            void* user_data = null;
-            byte ret = ImGuiNative.igInputTextMultiline(native_label, native_buf, buf_size, size, flags, callback, user_data);
-            return ret != 0;
-        }
-        public static bool InputTextMultiline(string label, string buf, uint buf_size, Vector2 size, ImGuiInputTextFlags flags, ImGuiInputTextCallback callback)
-        {
-            int label_byteCount = Encoding.UTF8.GetByteCount(label);
-            byte* native_label = stackalloc byte[label_byteCount + 1];
-            fixed (char* label_ptr = label)
-            {
-                int native_label_offset = Encoding.UTF8.GetBytes(label_ptr, label.Length, native_label, label_byteCount);
-                native_label[native_label_offset] = 0;
-            }
-            int buf_byteCount = Encoding.UTF8.GetByteCount(buf);
-            byte* native_buf = stackalloc byte[buf_byteCount + 1];
-            fixed (char* buf_ptr = buf)
-            {
-                int native_buf_offset = Encoding.UTF8.GetBytes(buf_ptr, buf.Length, native_buf, buf_byteCount);
-                native_buf[native_buf_offset] = 0;
-            }
-            void* user_data = null;
-            byte ret = ImGuiNative.igInputTextMultiline(native_label, native_buf, buf_size, size, flags, callback, user_data);
-            return ret != 0;
-        }
-        public static bool InputTextMultiline(string label, string buf, uint buf_size, Vector2 size, ImGuiInputTextFlags flags, ImGuiInputTextCallback callback, IntPtr user_data)
-        {
-            int label_byteCount = Encoding.UTF8.GetByteCount(label);
-            byte* native_label = stackalloc byte[label_byteCount + 1];
-            fixed (char* label_ptr = label)
-            {
-                int native_label_offset = Encoding.UTF8.GetBytes(label_ptr, label.Length, native_label, label_byteCount);
-                native_label[native_label_offset] = 0;
-            }
-            int buf_byteCount = Encoding.UTF8.GetByteCount(buf);
-            byte* native_buf = stackalloc byte[buf_byteCount + 1];
-            fixed (char* buf_ptr = buf)
-            {
-                int native_buf_offset = Encoding.UTF8.GetBytes(buf_ptr, buf.Length, native_buf, buf_byteCount);
-                native_buf[native_buf_offset] = 0;
-            }
-            void* native_user_data = (void*)user_data.ToPointer();
-            byte ret = ImGuiNative.igInputTextMultiline(native_label, native_buf, buf_size, size, flags, callback, native_user_data);
-            return ret != 0;
-        }
         public static bool Selectable(string label)
         {
             int label_byteCount = Encoding.UTF8.GetByteCount(label);

src/ImGui.NET/ImGui.Manual.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Numerics;
 using System.Text;
 
 namespace ImGuiNET
@@ -110,6 +111,67 @@ namespace ImGuiNET
             return result != 0;
         }
 
+        public static bool InputTextMultiline(
+            string label,
+            ref string input,
+            uint maxLength,
+            Vector2 size) => InputTextMultiline(label, ref input, maxLength, size, 0, null, IntPtr.Zero);
+
+        public static bool InputTextMultiline(
+            string label,
+            ref string input,
+            uint maxLength,
+            Vector2 size,
+            ImGuiInputTextFlags flags) => InputTextMultiline(label, ref input, maxLength, size, flags, null, IntPtr.Zero);
+
+        public static bool InputTextMultiline(
+            string label,
+            ref string input,
+            uint maxLength,
+            Vector2 size,
+            ImGuiInputTextFlags flags,
+            ImGuiInputTextCallback callback) => InputTextMultiline(label, ref input, maxLength, size, flags, callback, IntPtr.Zero);
+
+        public static bool InputTextMultiline(
+            string label,
+            ref string input,
+            uint maxLength,
+            Vector2 size,
+            ImGuiInputTextFlags flags,
+            ImGuiInputTextCallback callback,
+            IntPtr user_data)
+        {
+            int labelByteCount = Encoding.UTF8.GetByteCount(label);
+            byte* labelBytes = stackalloc byte[labelByteCount];
+            fixed (char* labelPtr = label)
+            {
+                Encoding.UTF8.GetBytes(labelPtr, label.Length, labelBytes, labelByteCount);
+            }
+
+            int bytesNeeded = Encoding.UTF8.GetByteCount(input);
+            int stackBufSize = Math.Max((int)maxLength, bytesNeeded);
+            byte* bufBytes = stackalloc byte[stackBufSize];
+            fixed (char* u16Ptr = input)
+            {
+                Encoding.UTF8.GetBytes(u16Ptr, input.Length, bufBytes, stackBufSize);
+            }
+
+            byte result = ImGuiNative.igInputTextMultiline(
+                labelBytes,
+                bufBytes,
+                (uint)stackBufSize,
+                size,
+                flags,
+                callback,
+                user_data.ToPointer());
+            if (!Util.AreStringsEqual(input, bufBytes))
+            {
+                input = Util.StringFromPtr(bufBytes);
+            }
+
+            return result != 0;
+        }
+
         public static bool InputText(
             string label,
             IntPtr buf,