Implement screenshot function

src/ArcadeMaker.Core/IGame.Funcs.cs

@@ -1017,4 +1017,13 @@ IValue SetViewFollowingTarget(Exp.Instance? _, IValue?[] args)
     /// <returns>The index of the currently activated room as a <see cref="NumberValue"/>.</returns>
     [EngineFunc]
     IValue GetRoomIndex(Exp.Instance? _, IValue?[] args) => Rooms.IndexOf(GetActivatedRoom().Model).ToExp();
+
+    /// <summary>
+    /// Takes screenshot from texture.
+    /// </summary>
+    /// <param name="_"></param>
+    /// <param name="args"></param>
+    /// <returns></returns>
+    [EngineFunc]
+    Exp.Void TakeScreenshot(Exp.Instance? _, IValue?[] args);
 }

src/ArcadeMaker.IDE/Debugging/FutileGame.cs

@@ -74,4 +74,6 @@ public void SetCaption(string caption) { }
     public Exp.Void ResumeSound(Exp.Instance? _, IValue?[] args) => Exp.Void.Return;
 
     public Exp.Void ResumeAllSounds(Exp.Instance? _, IValue?[] args) => Exp.Void.Return;
+
+    public Exp.Void TakeScreenshot(Exp.Instance? _, IValue?[] args) => Exp.Void.Return;
 }

src/Engines/MonoGame/Core/ArcadeMakerMonoGame.cs

@@ -19,6 +19,7 @@
 using MonoGame.Extended.ViewportAdapters;
 using System;
 using System.Collections.Generic;
+using System.Diagnostics;
 using System.Globalization;
 using System.IO;
 using System.IO.Pipes;
@@ -86,6 +87,9 @@ public RoomInstance? CurrentRoom
         public TextureAtlas MainTextureAtlas { get; private set; }
         public string MainTextureAtlasFilePath { get; set; }
 
+        private RenderTarget2D renderTarget = null;
+        private bool IsInsideDraw = false;
+
         // runtime private data
         private GameRunner<ArcadeMakerMonoGame> GameRunner { get; set; }
         private RectangleF roomBounds;
@@ -182,6 +186,10 @@ protected override void Initialize()
             LocalizationManager.SetCulture(selectedLanguage);
 
             SpriteBatch = new SpriteBatch(GraphicsDevice);
+            renderTarget = new RenderTarget2D(
+                GraphicsDevice,
+                graphicsDeviceManager.PreferredBackBufferWidth,
+                graphicsDeviceManager.PreferredBackBufferHeight);
 
             try
             {
@@ -380,7 +388,21 @@ protected override void Draw(GameTime gameTime)
         {
             if (isOnError || CurrentRoom == null)
                 return;
+            IsInsideDraw = true;
+            try
+            {
+                DrawScene();
+            }
+            finally
+            {
+                IsInsideDraw = false;
+            }
+
+            base.Draw(gameTime);
+        }
 
+        private void DrawScene()
+        {
             GraphicsDevice.Clear(backColor);
 
             // if views are defined, we need to draw the room for each view, applying the corresponding camera transformations.
@@ -451,8 +473,6 @@ protected override void Draw(GameTime gameTime)
 
                 SpriteBatch.End();
             }
-
-            base.Draw(gameTime);
         }
 
         public void DrawBackgrounds(int w, int h, Matrix transformMatrix)
@@ -744,6 +764,18 @@ public Exp.Void DrawEllipse(Exp.Instance? _, IValue?[] args)
             return Exp.Void.Return;
         }
 
+
+        public Exp.Void TakeScreenshot(Exp.Instance? _, IValue?[] args)
+        {
+            if(!IsInsideDraw)
+                throw new InvalidOperationException(
+                    "TakeScreenshot must be called from inside Draw().");
+            GraphicsDevice.SetRenderTarget(renderTarget);
+            DrawScene();
+            GraphicsDevice.SetRenderTarget(null);
+            return Exp.Void.Return;
+        }
+
         public (int x, int y) MousePositionInWindow
         {
             get