Fake multi-monitor fullscreen in monogame: form can't be big enough

Question

I run a triple-monitor setup and I am working on a graphics demo in MonoGame that I decided (heck why not? let's give it the ability to maximize across all displays!) so I used this code:

 graphics.IsFullScreen = false;
        graphics.ApplyChanges();
        //get dimensions of box that will cover all displays and set window to it.
        int xPos = System.Windows.Forms.Screen.AllScreens.OrderBy(x => x.Bounds.X).Select(x => x.Bounds.X).First();
        int yPos = System.Windows.Forms.Screen.AllScreens.OrderBy(y => y.Bounds.Y).Select(y => y.Bounds.Y).First();
        form.FormBorderStyle = System.Windows.Forms.FormBorderStyle.None;
        form.Location = new System.Drawing.Point(xPos, yPos);
        int xWidth = System.Windows.Forms.Screen.AllScreens.OrderByDescending(x => x.Bounds.X).Select(x => x.Bounds.X + x.Bounds.Width).First() - xPos;
        int yHeight = System.Windows.Forms.Screen.AllScreens.OrderByDescending(y => y.Bounds.Y).Select(y => y.Bounds.Y + y.Bounds.Height).First() - yPos;
        form.MaximumSize = new System.Drawing.Size(0, 0);

        form.Width = xWidth;
        form.Height = yHeight;
      //  graphics.PreferredBackBufferWidth = xWidth;
     //   graphics.PreferredBackBufferHeight = yHeight;
        graphics.ApplyChanges();
        Properties.Settings.Default.FakeFullScreen = true;
    }

and of course a 2nd function to undo it.

This worked fine when I had one of my monitors set above the others for testing, but when I set windows layout to place them all side-by-side (giving a resolution of 5760x1080) I was throwing an invalid parameter error on the graphics.ApplyChanges(). So I commented out the graphics code and set the form width manually and discovered that evidently I am not allowed to have a form wider than 4096 pixels.

Is there a way around this? I am open to all suggestions, including having more than one window side-by-side to draw to, but I would need some code to show me how to target a 2nd form.

Please and thank you.

Answer 1

This is a DirectX 9/Windows Phone 7 limitation of texture sizes limited to 4096 x 4096 by the use of the "Reach Graphics Profile".

The final displayed image is a single texture of the composite of all spritebatches, the size cannot exceed the maximum texture size.

To correct the issue:

1. Make sure your video card supports larger textures: run dxdiag.exe (most modern video cards do, given enough memory).
2. Enable the " hidef " profile to allow full DX9, DX10, and DX11 modes.

To enable "Hidef", modify your Game1.cs constructor use this code :

public Game1()
        {
            graphics = new GraphicsDeviceManager(this);
            Content.RootDirectory = "Content";
            graphics.GraphicsProfile = GraphicsProfile.HiDef;
            graphics.ApplyChanges();
            // any additional code goes here
        }

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The alternative is to use OpenGL, which ignores the graphics profile and uses the optimal version for your video card.