port imgui's memory editor sample

src/ImGui.NET.SampleProgram.Net46/ImGui.NET.SampleProgram.Net46.csproj

@@ -20,6 +20,7 @@
   <ItemGroup>
     <Compile Include="..\ImGui.NET.SampleProgram\Program.cs" />
     <Compile Include="..\ImGui.NET.SampleProgram\SampleWindow.cs" />
+    <Compile Include="..\ImGui.NET.SampleProgram\MemoryEditor.cs" />    
   </ItemGroup>
   <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|x64' " />
   <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|x64' " />

src/ImGui.NET.SampleProgram/ImGui.NET.SampleProgram.csproj

@@ -16,6 +16,7 @@
     <BaseNuGetRuntimeIdentifier Condition="'$(OSTarget)' == 'Windows_NT'">win7</BaseNuGetRuntimeIdentifier>
   </PropertyGroup>
   <ItemGroup>
+    <Compile Include="MemoryEditor.cs" />
     <Compile Include="Program.cs" />
     <Compile Include="SampleWindow.cs" />
   </ItemGroup>

src/ImGui.NET.SampleProgram/MemoryEditor.cs

@@ -0,0 +1,271 @@
+using System;
+using System.Globalization;
+using ImGuiNET;
+using System.Numerics;
+
+namespace ImGuiNET
+{
+    // C# port of ocornut's imgui_memory_editor.h - https://gist.github.com/ocornut/0673e37e54aff644298b
+
+    // Mini memory editor for ImGui (to embed in your game/tools)
+    // v0.10
+    // Animated gif: https://cloud.githubusercontent.com/assets/8225057/9028162/3047ef88-392c-11e5-8270-a54f8354b208.gif
+    //
+    // You can adjust the keyboard repeat delay/rate in ImGuiIO.
+    // The code assume a mono-space font for simplicity! If you don't use the default font, use ImGui::PushFont()/PopFont() to switch to a mono-space font before caling this.
+    //
+    // Usage:
+    //   static MemoryEditor memory_editor;                                                     // save your state somewhere
+    //   memory_editor.Draw("Memory Editor", mem_block, mem_block_size, (size_t)mem_block);     // run
+
+    public class MemoryEditor
+    {
+        bool AllowEdits;
+        int Rows;
+        int DataEditingAddr;
+        bool DataEditingTakeFocus;
+        byte[] DataInput = new byte[32];
+        byte[] AddrInput = new byte[32];
+
+        public MemoryEditor()
+        {
+            Rows = 16;
+            DataEditingAddr = -1;
+            DataEditingTakeFocus = false;
+            AllowEdits = true;
+        }
+
+        private static string FixedHex(int v, int count)
+        {
+            return v.ToString("X").PadLeft(count, '0');
+        }
+
+        private static bool TryHexParse(byte[] bytes, out int result)
+        {
+            string input = System.Text.Encoding.UTF8.GetString(bytes).ToString();
+            return int.TryParse(input, NumberStyles.AllowHexSpecifier, CultureInfo.CurrentCulture, out result);
+        }
+
+        private static void ReplaceChars(byte[] bytes, string input)
+        {
+            var address = System.Text.Encoding.ASCII.GetBytes(input);
+            for (int i = 0; i < bytes.Length; i++)
+            {
+                bytes[i] = (i < address.Length) ? address[i] : (byte)0;
+            }
+        }
+
+        public unsafe void Draw(string title, byte[] mem_data, int mem_size, int base_display_addr = 0)
+        {
+            if (!ImGui.BeginWindow(title))
+            {
+                ImGui.EndWindow();
+                return;
+            }
+
+            float line_height = ImGuiNative.igGetTextLineHeight();
+            int line_total_count = (mem_size + Rows - 1) / Rows;
+
+            ImGuiNative.igSetNextWindowContentSize(new Vector2(0.0f, line_total_count * line_height));
+            ImGui.BeginChild("##scrolling", new Vector2(0, -ImGuiNative.igGetItemsLineHeightWithSpacing()), false, 0);
+
+            ImGui.PushStyleVar(StyleVar.FramePadding, new Vector2(0, 0));
+            ImGui.PushStyleVar(StyleVar.ItemSpacing, new Vector2(0, 0));
+
+            int addr_digits_count = 0;
+            for (int n = base_display_addr + mem_size - 1; n > 0; n >>= 4)
+                addr_digits_count++;
+
+            float glyph_width = ImGui.GetTextSize("F").X;
+            float cell_width = glyph_width * 3; // "FF " we include trailing space in the width to easily catch clicks everywhere
+
+            var clipper = new ImGuiListClipper(line_total_count, line_height);
+            int visible_start_addr = clipper.DisplayStart * Rows;
+            int visible_end_addr = clipper.DisplayEnd * Rows;
+
+            bool data_next = false;
+
+            if (!AllowEdits || DataEditingAddr >= mem_size)
+                DataEditingAddr = -1;
+
+            int data_editing_addr_backup = DataEditingAddr;
+
+            if (DataEditingAddr != -1)
+            {
+                if (ImGui.IsKeyPressed(ImGui.GetKeyIndex(GuiKey.UpArrow)) && DataEditingAddr >= Rows) { DataEditingAddr -= Rows; DataEditingTakeFocus = true; }
+                else if (ImGui.IsKeyPressed(ImGui.GetKeyIndex(GuiKey.DownArrow)) && DataEditingAddr < mem_size - Rows) { DataEditingAddr += Rows; DataEditingTakeFocus = true; }
+                else if (ImGui.IsKeyPressed(ImGui.GetKeyIndex(GuiKey.LeftArrow)) && DataEditingAddr > 0) { DataEditingAddr -= 1; DataEditingTakeFocus = true; }
+                else if (ImGui.IsKeyPressed(ImGui.GetKeyIndex(GuiKey.RightArrow)) && DataEditingAddr < mem_size - 1) { DataEditingAddr += 1; DataEditingTakeFocus = true; }
+            }
+            if ((DataEditingAddr / Rows) != (data_editing_addr_backup / Rows))
+            {
+                // Track cursor movements
+                float scroll_offset = ((DataEditingAddr / Rows) - (data_editing_addr_backup / Rows)) * line_height;
+                bool scroll_desired = (scroll_offset < 0.0f && DataEditingAddr < visible_start_addr + Rows * 2) || (scroll_offset > 0.0f && DataEditingAddr > visible_end_addr - Rows * 2);
+                if (scroll_desired)
+                    ImGuiNative.igSetScrollY(ImGuiNative.igGetScrollY() + scroll_offset);
+            }
+
+            for (int line_i = clipper.DisplayStart; line_i < clipper.DisplayEnd; line_i++) // display only visible items
+            {
+                int addr = line_i * Rows;
+                ImGui.Text(FixedHex(base_display_addr + addr, addr_digits_count) + ": ");
+                ImGui.SameLine();
+
+                // Draw Hexadecimal
+                float line_start_x = ImGuiNative.igGetCursorPosX();
+                for (int n = 0; n < Rows && addr < mem_size; n++, addr++)
+                {
+                    ImGui.SameLine(line_start_x + cell_width * n);
+
+                    if (DataEditingAddr == addr)
+                    {
+                        // Display text input on current byte
+                        ImGui.PushID(addr);
+
+                        // FIXME: We should have a way to retrieve the text edit cursor position more easily in the API, this is rather tedious.
+                        TextEditCallback callback = (data) =>
+                        {
+                            int* p_cursor_pos = (int*)data->UserData;
+                            if (!data->HasSelection())
+                                *p_cursor_pos = data->CursorPos;
+                            return 0;
+                        };
+                        int cursor_pos = -1;
+                        bool data_write = false;
+                        if (DataEditingTakeFocus)
+                        {
+                            ImGui.SetKeyboardFocusHere();
+                            ReplaceChars(DataInput, FixedHex(mem_data[addr], 2));
+                            ReplaceChars(AddrInput, FixedHex(base_display_addr + addr, addr_digits_count));
+                        }
+                        ImGui.PushItemWidth(ImGui.GetTextSize("FF").X);
+
+                        var flags = InputTextFlags.CharsHexadecimal | InputTextFlags.EnterReturnsTrue | InputTextFlags.AutoSelectAll | InputTextFlags.NoHorizontalScroll | InputTextFlags.AlwaysInsertMode | InputTextFlags.CallbackAlways;
+                        if (ImGui.InputText("##data", DataInput, 32, flags, callback, new IntPtr(&cursor_pos)))
+                            data_write = data_next = true;
+                        else if (!DataEditingTakeFocus && !ImGui.IsLastItemActive())
+                            DataEditingAddr = -1;
+
+                        DataEditingTakeFocus = false;
+                        ImGui.PopItemWidth();
+                        if (cursor_pos >= 2)
+                            data_write = data_next = true;
+                        if (data_write)
+                        {
+                            int data;
+                            if (TryHexParse(DataInput, out data))
+                                 mem_data[addr] = (byte)data;
+                        }
+                        ImGui.PopID();
+                    }
+                    else
+                    {
+                        ImGui.Text(FixedHex(mem_data[addr], 2));
+                        if (AllowEdits && ImGui.IsLastItemHovered() && ImGui.IsMouseClicked(0))
+                        {
+                            DataEditingTakeFocus = true;
+                            DataEditingAddr = addr;
+                        }
+                    }
+                }
+
+                ImGui.SameLine(line_start_x + cell_width * Rows + glyph_width * 2);
+                //separator line drawing replaced by printing a pipe char
+
+                // Draw ASCII values
+                addr = line_i * Rows;
+                var asciiVal = new System.Text.StringBuilder(2 + Rows);
+                asciiVal.Append("| ");
+                for (int n = 0; n < Rows && addr < mem_size; n++, addr++)
+                {
+                    int c = mem_data[addr];
+                    asciiVal.Append((c >= 32 && c < 128) ? Convert.ToChar(c) : '.');
+                }
+                ImGui.TextUnformatted(asciiVal.ToString());  //use unformatted, so string can contain the '%' character
+            }
+            //clipper.End();  //not implemented
+            ImGui.PopStyleVar(2);
+
+            ImGui.EndChild();
+
+            if (data_next && DataEditingAddr < mem_size)
+            {
+                DataEditingAddr = DataEditingAddr + 1;
+                DataEditingTakeFocus = true;
+            }
+
+            ImGui.Separator();
+                
+            ImGuiNative.igAlignFirstTextHeightToWidgets();
+            ImGui.PushItemWidth(50);
+            ImGuiNative.igPushAllowKeyboardFocus(false);
+            int rows_backup = Rows;
+            if (ImGui.DragInt("##rows", ref Rows, 0.2f, 4, 32, "%.0f rows"))
+            {
+                if (Rows <= 0) Rows = 4;
+                Vector2 new_window_size = ImGui.GetWindowSize();
+                new_window_size.X += (Rows - rows_backup) * (cell_width + glyph_width);
+                ImGui.SetWindowSize(new_window_size);
+            }
+            ImGuiNative.igPopAllowKeyboardFocus();
+            ImGui.PopItemWidth();
+            ImGui.SameLine();
+            ImGui.Text(string.Format(" Range {0}..{1} ", FixedHex(base_display_addr, addr_digits_count), 
+                FixedHex(base_display_addr + mem_size - 1, addr_digits_count)));
+            ImGui.SameLine();
+            ImGui.PushItemWidth(70);
+            if (ImGui.InputText("##addr", AddrInput, 32, InputTextFlags.CharsHexadecimal | InputTextFlags.EnterReturnsTrue, null))
+            {
+                int goto_addr;
+                if (TryHexParse(AddrInput, out goto_addr))
+                {
+                    goto_addr -= base_display_addr;
+                    if (goto_addr >= 0 && goto_addr < mem_size)
+                    {
+                        ImGui.BeginChild("##scrolling");
+                        ImGuiNative.igSetScrollFromPosY(ImGui.GetCursorStartPos().Y + (goto_addr / Rows) * ImGuiNative.igGetTextLineHeight());
+                        ImGui.EndChild();
+                        DataEditingAddr = goto_addr;
+                        DataEditingTakeFocus = true;
+                    }
+                }
+            }
+            ImGui.PopItemWidth();
+            
+            ImGui.EndWindow();
+        }
+    }
+
+    //Not a proper translation, because ImGuiListClipper uses imgui's internal api.
+    //Thus SetCursorPosYAndSetupDummyPrevLine isn't reimplemented, but SetCursorPosY + SetNextWindowContentSize seems to be working well instead.
+    //TODO expose clipper through newer cimgui version
+    internal class ImGuiListClipper
+    {
+        public float StartPosY;
+        public float ItemsHeight;
+        public int ItemsCount, StepNo, DisplayStart, DisplayEnd;
+
+        public ImGuiListClipper(int items_count = -1, float items_height = -1.0f)
+        {
+            Begin(items_count, items_height);
+        }
+
+        public void Begin(int count, float items_height = -1.0f)
+        {
+            StartPosY = ImGuiNative.igGetCursorPosY();
+            ItemsHeight = items_height;
+            ItemsCount = count;
+            StepNo = 0;
+            DisplayEnd = DisplayStart = -1;
+            if (ItemsHeight > 0.0f)
+            {
+                ImGui.CalcListClipping(ItemsCount, ItemsHeight, ref DisplayStart, ref DisplayEnd); // calculate how many to clip/display
+                if (DisplayStart > 0)
+                    //SetCursorPosYAndSetupDummyPrevLine(StartPosY + DisplayStart * ItemsHeight, ItemsHeight); // advance cursor
+                    ImGuiNative.igSetCursorPosY(StartPosY + DisplayStart * ItemsHeight);
+                StepNo = 2;
+            }
+        }
+    }
+}

src/ImGui.NET.SampleProgram/SampleWindow.cs

@@ -29,6 +29,9 @@ namespace ImGuiNET
         private float _scaleFactor;
         private System.Numerics.Vector3 _positionValue = new System.Numerics.Vector3(500);
 
+        private MemoryEditor _memoryEditor = new MemoryEditor();
+        private byte[] _memoryEditorData;
+
         public unsafe SampleWindow()
         {
             int desiredWidth = 960, desiredHeight = 540;
@@ -59,6 +62,13 @@ namespace ImGuiNET
                 ptr[i] = 0;
             }
 
+            _memoryEditorData = new byte[1024];
+            var rnd = new Random();
+            for (int i = 0; i < _memoryEditorData.Length; i++)
+            {
+                _memoryEditorData[i] = (byte) rnd.Next(255);
+            }
+
             CreateDeviceObjects();
         }
 
@@ -290,6 +300,8 @@ namespace ImGuiNET
 
             ImGui.EndWindow();
 
+            _memoryEditor.Draw("Memory editor", _memoryEditorData, _memoryEditorData.Length);
+
             if (ImGui.GetIO().AltPressed && ImGui.GetIO().KeysDown[(int)Key.F4])
             {
                 _nativeWindow.Close();

src/ImGui.NET/ImGui.cs

@@ -464,7 +464,7 @@ namespace ImGuiNET
             return size;
         }
 
-        public static void SetWindowSize(Vector2 size, SetCondition cond)
+        public static void SetWindowSize(Vector2 size, SetCondition cond = 0)
         {
             ImGuiNative.igSetWindowSize(size, cond);
         }
@@ -627,6 +627,13 @@ namespace ImGuiNET
             ImGuiNative.igEndChildFrame();
         }
 
+        public static int GetKeyIndex(GuiKey key)
+        {
+            //TODO this got exported by later version of cimgui, call ImGuiNative after upgrading
+            IO io = GetIO();
+            return io.KeyMap[key];
+        }
+
         public static bool IsKeyDown(int keyIndex)
         {
             return ImGuiNative.igIsKeyDown(keyIndex);