i create a model in 3d but when i make logout and go to login class i don´t want show the model as been create in world class

but i don´t know how remove the model

i find soluction

with this code

this.Game.GameSystems.Remove(this);

i find the soluction i only have to add a new line of code

this.Game.GameSystems.Remove(this);

i find the soluction i only have to add a new line of code

this.Game.GameSystems.Remove(this);

I have no idea what language or library you are using, but be careful of calling a method like remove() with a this pointer or reference. If you access any members of the object following that line, it is likely to crash your application (depending on what language you are using).

C++ example:

ListOfThings things;

void removeThing(Thing *t)
{
    things.remove(t);
}

class Thing
{
public:
    void destroyMe()
    {
        remove(this);
        print(health); // crash, this points to deallocated memory
    }

    int health;
};

It is normally better to remove things at a higher level than have an instance remove itself from a container.

i using sharpdx and i programaing in c#

No idea how C# handles this. Guess since it is garbage collected, the instance will still exist for the rest of the method so you're probably okay. Its just conceptually confusing to have objects delete themselves generally speaking.

when i use this Game.GameSystems.Remove(this);

the game gets completely crazy

my buttons start flashing for wile and stop

this is code for world class

using System;
using SharpDX;
using SharpDX.Toolkit;
using System.Collections.Generic;
using SharpDX.Toolkit.Input;
using TomShane.Neoforce.Controls;
using SharpDX.Direct3D;
using SharpDX.Direct3D11;
using SharpDX.Toolkit.Content;
using SharpDX.Toolkit.Graphics;
using System.Text;
using SharpDX.Windows;



namespace TomShane.Neoforce.Central
{
    internal sealed class World : GameSystem
    {
        private Manager NeoManager;
        string texto;
        private SpriteBatch spriteBatch;
        private SpriteFont arial16BMFont;
       // private PointerManager pointer;
        private Model model;
        private List<Model> models;
        private BoundingSphere modelBounds;
        private Matrix world;
        private Matrix view;
        private Matrix projection;
        private Window inventory;
        private Window Charactersstatus;
        private Window gameexit;
        TomShane.Neoforce.Controls.Console con1;
        TomShane.Neoforce.Controls.Console con2;
        private Game _game=null;
        int i = 0;

        private TomShane.Neoforce.Controls.TabControl tbc;
        public World(Game game, Manager ola, string text)
            : base(game)
        {
            _game =game;
            NeoManager = ola;
            texto = text;
            System.Console.Write(texto);
           // pointer = new PointerManager(game);
           

            // this game system has something to draw - enable drawing by default
            // this can be disabled to make objects drawn by this system disappear
            Visible = true;

            // this game system has logic that needs to be updated - enable update by default
            // this can be disabled to simulate a "pause" in logic update
            Enabled = true;

            // add the system itself to the systems list, so that it will get initialized and processed properly
            // this can be done after game initialization - the Game class supports adding and removing of game systems dynamically
            _game.GameSystems.Add(this);

           // NeoManager = new Manager(game);
        }

        /// <summary>
        /// Initialize here anything that depends on other services
        /// </summary>
        public override void Initialize()
        {


          //  NeoManager.Initialize();
            base.Initialize();

            // get the camera service from service registry

        }
        private void HandlePlayerInput()
        {
            KeyboardState currentKeyboardState = NeoManager.KeyboardManager.GetState();


            if (currentKeyboardState.IsKeyDown(Keys.A))
            {

            }
            if (currentKeyboardState.IsKeyDown(Keys.D))
            {

            }

            if (currentKeyboardState.IsKeyDown(Keys.W))
            {

            }

            if (currentKeyboardState.IsKeyDown(Keys.S))
            {

            }
            if (currentKeyboardState.IsKeyPressed(Keys.I))
            {
                inventory.Show();


            }
            if (currentKeyboardState.IsKeyDown(Keys.C))
            {
                Charactersstatus.Show();


            }
            if (currentKeyboardState.IsKeyDown(Keys.Escape))
            {

                gameexit.Show();

            }
            if (currentKeyboardState.IsKeyDown(Keys.Space))
            {


            }
            if (currentKeyboardState.IsKeyDown(Keys.M))
            {

            }



        }
        private void Inventory()
        {
            inventory = new Window(NeoManager);
            inventory.Init();
            inventory.Text = "Inventory";
            inventory.Width = 450;
            inventory.Height = 250;
            inventory.Center();
            inventory.Visible = true;
            inventory.CloseButtonVisible = true;
            inventory.Resizable = false;
            inventory.Movable = true;
            inventory.IconVisible = false;
            inventory.Close();
            NeoManager.Add(inventory);

        }
        private void ExitGamer()
        {
            gameexit = new Window(NeoManager);
            gameexit.Init();
            gameexit.Text = "Game Exit";
            gameexit.Width = 200;
            gameexit.Height = 220;
            gameexit.Center();
            gameexit.Visible = true;
            gameexit.CloseButtonVisible = true;
            gameexit.Resizable = false;
            gameexit.Movable = true;
            gameexit.Close();
            gameexit.IconVisible = false;
            Button Sair = new Button(NeoManager);
            Sair = new Button(NeoManager);
            Sair.Init();
            Sair.Width = 80;
            Sair.Parent = gameexit;
            Sair.Left = 50;
            Sair.Top = 0;
            Sair.Text = "Quit";
            Sair.TextColor = new SharpDX.Color(250, 250, 250);
            Sair.Click += new Controls.EventHandler(btnExit_Click1);
            Button Logout = new Button(NeoManager);
            Logout = new Button(NeoManager);
            Logout.Init();
            Logout.Width = 80;
            Logout.Parent = gameexit;
            Logout.Left = 50;
            Logout.Top = 40;
            Logout.Text = "Logout";
            Logout.TextColor = new SharpDX.Color(250, 250, 250);
            Logout.Click += new Controls.EventHandler(Logout_Click1);

            Button Characters = new Button(NeoManager);
            Characters = new Button(NeoManager);
            Characters.Init();
            Characters.Width = 80;
            Characters.Parent = gameexit;
            Characters.Left = 50;
            Characters.Top = 80;
            Characters.Text = "Characters";
            Characters.TextColor = new SharpDX.Color(250, 250, 250);


            Button Options = new Button(NeoManager);
            Options = new Button(NeoManager);
            Options.Init();
            Options.Width = 80;
            Options.Parent = gameexit;
            Options.Left = 50;
            Options.Top = 120;
            Options.Text = " Options";
            Options.TextColor = new SharpDX.Color(250, 250, 250);

            Button Canceling = new Button(NeoManager);
            Canceling = new Button(NeoManager);
            Canceling.Init();
            Canceling.Width = 80;
            Canceling.Parent = gameexit;
            Canceling.Left = 50;
            Canceling.Top = 160;
            Canceling.Text = "Cancel";
            Canceling.ModalResult = ModalResult.Cancel;
            Canceling.TextColor = new SharpDX.Color(250, 250, 250);
            NeoManager.Add(gameexit);
        }
        private void charactersstatus()
        {
            Charactersstatus = new Window(NeoManager);
            Charactersstatus.Init();
            Charactersstatus.Text = "Characters Status";
            Charactersstatus.Width = 450;
            Charactersstatus.Height = 250;
            Charactersstatus.Center();
            Charactersstatus.Visible = true;
            Charactersstatus.CloseButtonVisible = true;
            Charactersstatus.Resizable = false;
            Charactersstatus.Movable = true;
            Charactersstatus.Close();
            Charactersstatus.IconVisible = false;
            NeoManager.Add(Charactersstatus);


        }
        /// <summary>
        /// Load all graphics content here.
        /// </summary>
        protected override void LoadContent()
        {

            arial16BMFont = Content.Load<SpriteFont>("Arial16");

            // Load the model (by default the model is loaded with a BasicEffect. Use ModelContentReaderOptions to change the behavior at loading time.
            models = new List<Model>();
            foreach (var modelName in new[] { "helmet" })
            {
                model = Content.Load<Model>(modelName);

                // Enable default lighting  on model.
                BasicEffect.EnableDefaultLighting(model, true);

                models.Add(model);
            }
            model = models[0];

            // Instantiate a SpriteBatch
            spriteBatch = ToDisposeContent(new SpriteBatch(GraphicsDevice));

            Inventory();
            charactersstatus();
            InitConsole(texto);
            ExitGamer();
            base.LoadContent();

            // InitRes();
            // initialize the basic effect (shader) to draw the geometry, the BasicEffect class is similar to one from XNA

        }
        void btnExit_Click1(object sender, Controls.EventArgs e)
        {
            gameexit.Hide();
            System.Windows.Forms.DialogResult dialogResult = System.Windows.Forms.MessageBox.Show("Do you really want to exit ", "", System.Windows.Forms.MessageBoxButtons.YesNo, System.Windows.Forms.MessageBoxIcon.Question);
            if (dialogResult == System.Windows.Forms.DialogResult.Yes)
            {

                Game.Exit();
            }



        }

      
        /// <summary>
        /// Draw the scene content.
        /// </summary>
        /// <param name="gameTime">Structure containing information about elapsed game time.</param>


        /// <summary>
        /// Update the scene logic.
        /// </summary>
        /// <param name="gameTime">Structure containing information about elapsed game time.</param>
        public override void Update(GameTime gameTime)
        {
          // NeoManager.Update(gameTime);
            //var pointerState = pointer.GetState();
            //if (pointerState.Points.Count > 0 && pointerState.Points[0].EventType == PointerEventType.Released)
            //{
            //    // Go to next model when pressing key space
            //    model = models[(models.IndexOf(model) + 1) % models.Count];
            //}
           // Update(gameTime);
           /// Calculate the bounds of this model
            modelBounds = model.CalculateBounds();

            // Calculates the world and the view based on the model size
            const float MaxModelSize = 10.0f;
            var scaling = MaxModelSize / modelBounds.Radius;
            view = Matrix.LookAtRH(new Vector3(0, 0, MaxModelSize * 2.5f), new Vector3(0, 0, 0), Vector3.UnitY);
            projection = Matrix.PerspectiveFovRH(0.9f, (float)GraphicsDevice.BackBuffer.Width / GraphicsDevice.BackBuffer.Height, 0.1f, MaxModelSize * 10.0f);
            world = Matrix.Translation(-modelBounds.Center.X, -modelBounds.Center.Y, -modelBounds.Center.Z) * Matrix.Scaling(scaling) * Matrix.RotationY((float)gameTime.TotalGameTime.TotalSeconds);

            //if (con1.TextBoxVisible == true)
            //{
            //}
            //else {
            HandlePlayerInput();
           // model.Meshes.
            //}
             
         //   HandleInput();
            base.Update(gameTime);
            //  NeoManager.Update(gameTime);

            // get the total elapsed seconds since the start of the game

        }

        private void HandleInput()
        {
            
          // if (!con1.TextBoxVisible)
            //{
                HandlePlayerInput();
           // }
           // else
           // {
             //   con1.Focused = true;
               
                //Focused Input
           // }
            /**/
        }
        public override void Draw(GameTime gameTime)
        {

           
           NeoManager.BeginDraw(gameTime);
          // GraphicsDevice.BlendStates.Opaque(gameTime);
          GraphicsDevice.Clear(SharpDX.Color.CornflowerBlue);
            model.Draw(GraphicsDevice, world, view, projection);
            spriteBatch.Begin();

            spriteBatch.DrawString(arial16BMFont, "Press the pointer to switch models...\r\nCurrent Model: " + model.Name, new Vector2(16, 16), Color.White);

            spriteBatch.End();

           NeoManager.EndDraw();


            base.Draw(gameTime);

        }

     /*   public override void Draw3(GameTime gameTime)
        {


           // NeoManager.BeginDraw(gameTime);
            GraphicsDevice.Clear(SharpDX.Color.CornflowerBlue);
          ///  model.Draw(GraphicsDevice, world, view, projection);
          //  spriteBatch.Begin();

          //  spriteBatch.DrawString(arial16BMFont, "Press the pointer to switch models...\r\nCurrent Model: " + model.Name, new Vector2(16, 16), Color.White);

          //  spriteBatch.End();

          //  NeoManager.EndDraw();


            base.Draw(gameTime);

        }
        */
        private void InitConsole(string texto)
        {
            tbc = new TomShane.Neoforce.Controls.TabControl(NeoManager);
            con1 = new TomShane.Neoforce.Controls.Console(NeoManager);
            con2 = new TomShane.Neoforce.Controls.Console(NeoManager);


            tbc.Visible = true;
            //  con2.BackColor
            // Setup of TabControl, which will be holding both consoles
            tbc.Init();
            tbc.AddPage("Global");
            tbc.AddPage("Guild");
            tbc.AddPage("PARTY");
            tbc.AddPage("TRADE");

            tbc.Alpha = 220;
            tbc.Left = 0;
            tbc.Height = 220;
            tbc.Width = 450;
            tbc.Top = NeoManager.TargetHeight - tbc.Height - 32;

            tbc.Movable = true;
            tbc.Resizable = true;
            tbc.MinimumHeight = 96;
            tbc.MinimumWidth = 160;
           // tbc.TextColor= 
            tbc.TextColor = Color.White;
            tbc.TabPages[0].Add(con1);
            tbc.TabPages[1].Add(con2);
         //   NeoManager.Add(tbc);
            con1.Init();
           
            con1.Sender = texto;
            con2.Init();
            con2.Sender = texto;




            con2.Width = con1.Width = tbc.TabPages[0].ClientWidth;
            con2.Height = con1.Height = tbc.TabPages[0].ClientHeight;
            con2.Anchor = con1.Anchor = Anchors.All;

            con1.Channels.Add(new ConsoleChannel(0, "General", SharpDX.Color.Orange));
            con1.Channels.Add(new ConsoleChannel(1, "Private", SharpDX.Color.White));
            con1.Channels.Add(new ConsoleChannel(2, "System", SharpDX.Color.Yellow));
            con1.Channels.Add(new ConsoleChannel(3, "Guild", SharpDX.Color.Green));
            con1.Channels.Add(new ConsoleChannel(4, "Trade", SharpDX.Color.Red));

            // We want to share channels and message buffer in both consoles
            con2.Channels = con1.Channels;
            con2.MessageBuffer = con1.MessageBuffer;

            // In the second console we display only "Private" messages
            con2.ChannelFilter.Add(3);

            // Select default channels for each tab
            con1.SelectedChannel = 0;
            con2.SelectedChannel = 3;

            // Do we want to add timestamp or channel name at the start of every message?
            con1.MessageFormat = ConsoleMessageFormats.All;
            con2.MessageFormat = ConsoleMessageFormats.All;


            // Handler for altering incoming message
            con1.MessageSent += new ConsoleMessageEventHandler(con1_MessageSent);

            // We send initial welcome message to System channel
            con1.MessageBuffer.Add(new ConsoleMessage("System", "WELCOME TO THE SERVER! " + texto, 2));
            con1.Color = Color.Transparent;
            NeoManager.Add(tbc);
        }
        ////////////////////////////////////////////////////////////////////////////

        ////////////////////////////////////////////////////////////////////////////
        void con1_MessageSent(object sender, ConsoleMessageEventArgs e)
        {
            if (e.Message.Channel == 0)
            {
                //e.Message.Text = "(!) " + e.Message.Text;
            }
        }
        void Logout_Click1(object sender, Controls.EventArgs e)
        {

            //gameexit.Hide();
            System.Windows.Forms.DialogResult dialogResult = System.Windows.Forms.MessageBox.Show("Do you really want to exit ", "", System.Windows.Forms.MessageBoxButtons.YesNo, System.Windows.Forms.MessageBoxIcon.Question);
            if (dialogResult == System.Windows.Forms.DialogResult.Yes)
            {
            
               
                NeoManager.Remove(tbc);
                NeoManager.Remove(inventory);
                NeoManager.Remove(Charactersstatus);
                NeoManager.Remove(gameexit);
                model.Meshes.TrimExcess();
               GC.Collect();
            
                Login ola = new Login(Game, NeoManager);
                ola.Visible = true;
         
               
           
            }

        }
    }

}