Dim PresentParameters As New PresentParameters
            PresentParameters.BackBufferCount = 1
            PresentParameters.BackBufferFormat = Format.R5G6B5
            PresentParameters.BackBufferWidth = System.Windows.Forms.Screen.PrimaryScreen.Bounds.Width
            PresentParameters.BackBufferHeight = System.Windows.Forms.Screen.PrimaryScreen.Bounds.Height
            PresentParameters.Windowed = False
            PresentParameters.SwapEffect = SwapEffect.Discard
            PresentParameters.EnableAutoDepthStencil = False
            PresentParameters.Multisample = MultisampleType.FourSamples
            PresentParameters.MultisampleQuality = 2

            Dim Direct3D As New Direct3D
            DEVICE = New Device(Direct3D, 0, DeviceType.Hardware, Control.Handle, CreateFlags.HardwareVertexProcessing, PresentParameters)

Quote: Original post by user88
Hi Mathy. Yes, multisampling is the one of anti-aliasing (AA) techniques. There are lot of AA algorithms but directx uses the one and it is implemented in hardware level.

I think three things can be wrong that your AA is not working:

1) AA is disabled is graphics driver. I don't know how to do it with ATI graphics cars, but nVidia has "nVidia ControlPannel". In Vista as well as Window 7 you can find it in Control Pannel => Personalization => Display Settings => Advanced Settings => GeForce 9600 GSO tab (in my case) => Start the nVidia Control Pannel. Here select "Manage 3D settings" (left side of window) and "Application-controlled" for "Antialiasing - Mode".

2) Check MultisampleAntialias state. Use Device.GetRenderState(RenderState.MultisampleAntialias).

3) Can be that you set incorrect values of Multisample or MultisampleQuality in PresentParameters. Have a look to SmapleFramework that produces with SlimDX SDK. There are examples how to do that correctly.

Quote: Original post by Mathy
Multisample: MultisampleType.TwoSamples - Getting error "Invalid call (-2005530516)" upon initialization.

Multisample: MultisampleType.ThreeSamples - Getting error "Invalid call (-2005530516)" upon initialization.

Multisample: MultisampleType.FourSamples - Initializes just fine, but without antialiasing.

Multisample: MultisampleType.FiveSamples - Getting error "Invalid call (-2005530516)" upon initialization.

Multisample: MultisampleType.SixSamples - Getting error "Invalid call (-2005530516)" upon initialization.

Quote: Original post by Evil Steve
Does your card / driver actually support AA? If you look at the DX caps viewer (comes with the SDK), what do you see under:
Direct3D9 Devices/your_graphics_adapter/D3D Device Types / HAL / Adapter formats / D3DFMT_R5G6B5 (Fullscreen) / Render Format Compatibility / D3DFMT_R5G6B5 / ?

Quote: Original post by Mathy
Also, how would I programmatically see how many quality levels the graphics card supports etc?

static void BuildMultisampleTypeList(SettingsCombo9 combo){   List<MultisampleType> possibleMultisampleTypes = new List<MultisampleType>   {      MultisampleType.None,      MultisampleType.NonMaskable,      MultisampleType.TwoSamples,      MultisampleType.ThreeSamples,      MultisampleType.FourSamples,      MultisampleType.FiveSamples,      MultisampleType.SixSamples,      MultisampleType.SevenSamples,      MultisampleType.EightSamples,      MultisampleType.NineSamples,      MultisampleType.TenSamples,      MultisampleType.ElevenSamples,      MultisampleType.TwelveSamples,      MultisampleType.ThirteenSamples,      MultisampleType.FourteenSamples,      MultisampleType.FifteenSamples,      MultisampleType.SixteenSamples                                                                 };      int quality;      foreach (MultisampleType type in possibleMultisampleTypes)      {         if (GraphicsDeviceManager.Direct3D9Object.CheckDeviceMultisampleType(combo.AdapterOrdinal, combo.DeviceType, // Direct3D9Object is of SlimDX.Direct3D9.Direct3D type                                                                                     combo.AdapterFormat, combo.Windowed, type, out quality))         {            combo.MultisampleTypes.Add(type);            combo.MultisampleQualities.Add(quality); // note, quality (or quality - 1, can't remember) is highest value of quality level in current multisample type         }      }   }}