Monogame full screen Mouse Y position wrong

Windows
1

Hey,

So the issue i am having is when i start my app in full screen mode, or switch to full screen mode my mouse Y position is 20 pixels out. The app has to be started in the native desktop resolution for this to happen.

In my game i can change the resolution and full screen in the menu. Triggering full screen on and off two times (not one) will suddenly fix the issue and the mouse coordinates will be correct. I am assuming it has something to do with the windows title bar that is displayed in windowed mode as that is 20 pixels high.

Starting the game in windowed mode, then switching to full screen at the windows desktop resolution still triggers the 20 pixel difference. I have tried a bare bones XNA project on two computers and it does the same thing.

In the following code change your resolution to your native resolution. Move your mouse to the top of the screen and check the Y coordinates in the debug output.

’
public Game1()
{
graphics = new GraphicsDeviceManager(this);
Content.RootDirectory = “Content”;
}

    /// <summary>
    /// Allows the game to perform any initialization it needs to before starting to run.
    /// This is where it can query for any required services and load any non-graphic
    /// related content.  Calling base.Initialize will enumerate through any components
    /// and initialize them as well.
    /// </summary>
    protected override void Initialize()
    {
        // TODO: Add your initialization logic here
        base.Initialize();
        graphics.IsFullScreen = true;
        IsFixedTimeStep = false;
        graphics.PreferredBackBufferWidth = 1920;
        graphics.PreferredBackBufferHeight = 1080;
        graphics.ApplyChanges();
        IsMouseVisible = true;
    }

    /// <summary>
    /// LoadContent will be called once per game and is the place to load
    /// all of your content.
    /// </summary>
    protected override void LoadContent()
    {
        // Create a new SpriteBatch, which can be used to draw textures.
        spriteBatch = new SpriteBatch(GraphicsDevice);

        // TODO: use this.Content to load your game content here
    }

    /// <summary>
    /// UnloadContent will be called once per game and is the place to unload
    /// game-specific content.
    /// </summary>
    protected override void UnloadContent()
    {
        // TODO: Unload any non ContentManager content here
    }

    /// <summary>
    /// Allows the game to run logic such as updating the world,
    /// checking for collisions, gathering input, and playing audio.
    /// </summary>
    /// <param name="gameTime">Provides a snapshot of timing values.</param>
    protected override void Update(GameTime gameTime)
    {
        if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed || Keyboard.GetState().IsKeyDown(Keys.Escape))
            Exit();
        // TODO: Add your update logic here

        MouseState mouseState = Mouse.GetState();
        Debug.WriteLine(mouseState.X + ":" + mouseState.Y);         
        base.Update(gameTime);
    }

    /// <summary>
    /// This is called when the game should draw itself.
    /// </summary>
    /// <param name="gameTime">Provides a snapshot of timing values.</param>
    protected override void Draw(GameTime gameTime)
    {
        GraphicsDevice.Clear(Color.CornflowerBlue);

        // TODO: Add your drawing code here

        base.Draw(gameTime);
    }
}

}`

2

Is the result the same whether GraphicsDeviceManager.HardwareModeSwitch is true or false?

3

I’ve seen this sort of thing before.
I’d move some of that out of Initialize and up into the constructor to get this:

public Game1()
        {
            graphics = new GraphicsDeviceManager(this);
            Content.RootDirectory = "Content";
            graphics.IsFullScreen = true;
            IsFixedTimeStep = false;
            graphics.PreferredBackBufferWidth = 1920;
            graphics.PreferredBackBufferHeight = 1080;
            graphics.ApplyChanges();
            IsMouseVisible = true;
        }

Then the graphics should setup correctly.
I’d say not in this case, but in some cases the returned resolution won’t match due to card not supporting that mode of resolution (resulting in a closest match) and then you’d use presentation parameters to find the true resolution returned.
I’m pretty sure in this case tho - setting it in the constructor should fix the problem - cuz it happen to me before.

1 Like
4

You champion! Setting GraphicsDeviceManager.HardwareModeSwitch = false; fixed it.

I was scratching my head for hours, as in game switching from full screen to windowed twice would fix it.

1 Like
5

FYI you do not have to call ApplyChanges in the constructor, because the GraphicsDevice is not yet created.

6

Just wanted to ping this thread with a similar issue. Disabling HardwareModeSwitch works great for me, but now I want to start using it to support lower resolutions in my game. Unfortunately, the moment I turn it back on, the mouse cursor (even in fullscreen resolution) does not give relative coordinates to the whole screen anymore.

This creates an interesting problem for me in that I use the screen edge to detect map scrolling; not having an accurate margin means I can’t scroll sometimes.

Has anyone else encountered this? Could it be related to higher-DPI screens like the device I develop on, where normal window scale is different?

7

When are you enabling it. This is how i have it set up and works well for in game resolution changes

  graphics.HardwareModeSwitch = false;
  game.IsFixedTimeStep = vSync;
  graphics.IsFullScreen = fullScreen;
  graphics.PreferredBackBufferWidth = resolutionList[resolutionId].Width;
  graphics.PreferredBackBufferHeight = resolutionList[resolutionId].Height;
  graphics.SynchronizeWithVerticalRetrace = vSync;
  graphics.ApplyChanges();
  graphics.HardwareModeSwitch = true;