Thread: How to Antialias Direct3D?

There is an AntiAlias sample that ships with the DirectX 9 sdk. Source is included.

Okay, here is one of the methods to do it:

In the D3DPRESENT_PARAMETERS structure, set the MutliSampleType member to D3DMULTISAMPLE_NONMASKABLE. Then set the MultiSampleQuality member to your desired anti-aliased quality. You need to check the caps to make sure this is supported and to see how many quality levels are supported by the device.

The call you should look into is

IDirect3D9::CheckDeviceMultiSampleType

Then you specify the MutliSampleType and it will fill in the number of quality levels supported or return an error code if it's not supported.

Well.. gave it my best shot... hopefully i used it semi-correctly. (Feel free to scream at me if I used it wrong and am an idiot).
Seems to produce better image quality. So I'm guessing it works.. thnx for the help..

Oh yeah.. what exactly is MultiSampleQuality?? My device returns 4 Does that refer to 4x or something else?
If I don't subtract 1 from this number before setting I get a crash.

Code:

extern IDirect3D9 *g_pD3D9;
extern IDirect3DDevice9 * g_pD3DDevice9;

bool InitD3D(HWND hWnd)
{
  g_pD3D9 = Direct3DCreate9(D3D_SDK_VERSION);
	
  if(g_pD3D9 == NULL)
    return false;

  D3DDISPLAYMODE d3ddm;

  g_pD3D9->GetAdapterDisplayMode(D3DADAPTER_DEFAULT,
							   &d3ddm);

  D3DPRESENT_PARAMETERS d3dpp;

  memset(&d3dpp, 0, sizeof(d3dpp));
  d3dpp.BackBufferWidth = g_nScreenWidth;
  d3dpp.BackBufferHeight = g_nScreenHeight;
  d3dpp.BackBufferFormat = d3ddm.Format;
  d3dpp.BackBufferCount = 1;
  d3dpp.SwapEffect = D3DSWAPEFFECT_DISCARD;
  d3dpp.EnableAutoDepthStencil = true;
  d3dpp.AutoDepthStencilFormat = D3DFMT_D16;
  d3dpp.hDeviceWindow = hWnd;
  d3dpp.Windowed = true;
	
  DWORD total;
	  
if(SUCCEEDED(g_pD3D9->CheckDeviceMultiSampleType(D3DADAPTER_DEFAULT,		  							              D3DDEVTYPE_HAL,
									      d3ddm.Format,
									      true,
                                                     D3DMULTISAMPLE_NONMASKABLE,
									      &total)))
  {
    d3dpp.MultiSampleType = D3DMULTISAMPLE_NONMASKABLE;
    d3dpp.MultiSampleQuality = total - 1;
  }
  
d3dpp.FullScreen_RefreshRateInHz = D3DPRESENT_RATE_DEFAULT;
d3dpp.PresentationInterval = D3DPRESENT_INTERVAL_IMMEDIATE;

  if(FAILED(g_pD3D9->CreateDevice(D3DADAPTER_DEFAULT, 
							 D3DDEVTYPE_HAL, 
							 hWnd,
                                   D3DCREATE_SOFTWARE_VERTEXPROCESSING,
                                                         &d3dpp, 
							 &g_pD3DDevice9)))
     return false;
				
  return true;
}

Originally Posted by Deo

Well.. gave it my best shot... hopefully i used it semi-correctly. (Feel free to scream at me if I used it wrong and am an idiot).
Seems to produce better image quality. So I'm guessing it works.. thnx for the help..

Oh yeah.. what exactly is MultiSampleQuality?? My device returns 4 Does that refer to 4x or something else?
If I don't subtract 1 from this number before setting I get a crash.

Yes, the number of quality levels are 0-based as it states in the SDK docs. So you have 0, 1, 2, and 3 available to you. Looks like you are doing it correctly to me.

You can read about how MSAA works here:

http://www.3dcenter.de/artikel/multi...g/index3_e.php