I am trying to learn how to use DirectX9 under Win/XP and I and I have aproblem with multiple windowed view rendering. My windows are created as well as the D3D device. but when I get to the "CreateAdditionalSwapChain" statement, I get an access violation! Any help would be much appreciated... Thanks. LeLorrain Here is the relevant code: HRESULT D3Dgraphics::StartGraphics ( void ) { DEVICEINFO * device = m_D3Denum->getDevice(); COMBOINFO * combo = NULL; if (m_D3Dsystem != NULL) { m_D3Dsystem->Release (); m_D3Dsystem = NULL; } m_D3Dsystem = Direct3DCreate (D3D_SDK_VERSION); if (NULL == m_D3Dsystem) { throw Exception ("D3Dgraphics::StartGraphics", __LINE__, ::GetLastError(), "Graphic system not created"); } // Look for the graphic device for (UINT i = 0; i < device->D3DCombo.size(); i++) { bool Windowed = device->D3DCombo.Windowed; if ((device->D3DCombo.Windowed == m_Windowed) && (device->D3DCombo.D3DDevType == device->D3DDevType) && (device->D3DCombo.fmtAdapter == D3DdeviceInfo.AdapterFormat) && (device->D3DCombo.fmtBackBuffer == D3DdeviceInfo.BackBufferFmt) ) { combo = &device->D3DCombo; break; } } memset ((void *)&D3DdeviceInfo.D3Dparams, 0, sizeof (D3DdeviceInfo.D3Dparams)); D3DdeviceInfo.D3Dparams.Windowed = m_Windowed; D3DdeviceInfo.D3Dparams.BackBufferCount = 1; D3DdeviceInfo.D3Dparams.BackBufferFormat = D3DdeviceInfo.DisplayMode.Format; D3DdeviceInfo.D3Dparams.EnableAutoDepthStencil = true; D3DdeviceInfo.D3Dparams.AutoDepthStencilFormat = combo->fmtDepthStencil; D3DdeviceInfo.D3Dparams.MultiSampleType = combo->msType; D3DdeviceInfo.D3Dparams.SwapEffect = D3DSWAPEFFECT_DISCARD; // Check the stencil buffer depth if ((D3DFMT_D24S8 == combo->fmtDepthStencil) || (D3DFMT_D24X4S4 == combo->fmtDepthStencil) || (D3DFMT_D16 == combo->fmtDepthStencil) || (D3DFMT_D15S1 == combo->fmtDepthStencil)) { m_Stencil = true; } else { m_Stencil = false; } // Check windowed mode if (m_Windowed) { D3DdeviceInfo.D3Dparams.hDeviceWindow = m_hRenderWnd[0]; D3DdeviceInfo.D3Dparams.BackBufferWidth = m_ScreenWidth; D3DdeviceInfo.D3Dparams.BackBufferHeight = m_ScreenHeight; } else { D3DdeviceInfo.D3Dparams.hDeviceWindow = m_hMainWindow; D3DdeviceInfo.D3Dparams.BackBufferWidth = D3DdeviceInfo.DisplayMode.Width; D3DdeviceInfo.D3Dparams.BackBufferHeight = D3DdeviceInfo.DisplayMode.Height; } // Create the Direct3D device if (NULL == m_D3Dsystem->CreateDevice (device->nAdapter, device->D3DDevType, D3DdeviceInfo.D3Dparams.hDeviceWindow, combo->Behaviour, &D3DdeviceInfo.D3Dparams, &m_D3Ddevice)) { throw Exception ("D3Dgraphics::StartGraphics", __LINE__, ::GetLastError(), "Main Graphics Device NOT Created"); } // Create additional swap chains if required and possible if (m_Windowed && (m_hRenderWnd.size() > 1)) { m_D3Dchains = new LPDIRECT3DSWAPCHAIN[m_hRenderWnd.size()]; for (UINT i = 0; i < m_hRenderWnd.size(); i++) { D3DdeviceInfo.D3Dparams.BackBufferWidth = 0; D3DdeviceInfo.D3Dparams.BackBufferHeight = 0; D3DdeviceInfo.D3Dparams.hDeviceWindow = m_hRenderWnd; m_D3Dchains = NULL; if (NULL == m_D3Ddevice->CreateAdditionalSwapChain (&D3DdeviceInfo.D3Dparams, &(m_D3Dchains))) { int error = ::GetLastError(); std::stringstream os; os << "Additional Graphics Device #" << i <<" NOT Created" << std::ends; throw Exception ("D3Dgraphics::StartGraphics", __LINE__, error, (char *)os.str().c_str()); } } } // Clean Up Enumeration delete m_D3Denum; m_D3Denum = NULL; return SUCCESS; }

Thanks Endurion for your reply.

Yes, you are right, I should have checked the result with FAILED(), which seems to be the way to do in DirectX!

Further analysis of the HRESULT gave me a "D3DERR_INVALIDCALL" error code ant it seems that the device did not like the multi-sample value of 16 that the enumeration gave me for the combo of the adaptor... Hard-coding the value, I found that it would accept up to 8 samples.

Again, thank you.

LeLorrain