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Dance with me......

1) Get lost of the DDSCL_MODEX
2) Use (DirectDraw->)QueryInterface before you set the display mode.
3) use "FrontBuffer->GetAttachedSurface(&caps, &BackBuffer);" instead of AddAttachedSurface();

I Use addattchedSurface to attach the z buffer.

I would go for the following items in the following order:
1) DirectDrawCreate()
2) SetCooperativeLevel()
3) QueryInterface()
4) SetDisplayMode()
5) CreateSurface()
6) GetAttachedSurface()
( 7) CreateSurface + AddAttachedSurface for zbuffer)
8) CreateDevice()
9) CreateViewPort()
10) AddViewPort()
11) SetCurrentViewPort()
12) SetTransform()

etc etc..........

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Dance with me......

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Dance with me......

DDSURFACEDESC ddsd;

ZeroMemory(&ddsd, sizeof(ddsd));

ddsd.dwSize = sizeof(ddsd);
ddsd.dwFlags = DDSD_CAPS | DDSD_BACKBUFFERCOUNT;
ddsd.ddsCaps.dwCaps = DDSCAPS_PRIMARYSURFACE | DDSCAPS_FLIP | DDSCAPS_COMPLEX | DDSCAPS_3DDEVICE | DDSCAPS_VIDEOMEMORY;

ddsd.dwBackBufferCount = 1;

err = dd->CreateSurface(&ddsd, &FrontBuffer, NULL);

if (err != DD_OK)
{
ddsd.ddsCaps.dwCaps &= ~DDSCAPS_VIDEOMEMORY;
err = dd->CreateSurface(&ddsd, &FrontBuffer, NULL);
}

if (err != DD_OK)
{
return FALSE;
}

DDSCAPS caps;

caps.dwCaps = DDSCAPS_BACKBUFFER;
err = FrontBuffer->GetAttachedSurface(&caps, &BackBuffer);

if (err != DD_OK)
{
return FALSE;
}

memset(&ddsd, 0, sizeof(ddsd));
ddsd.dwSize = sizeof(DDSURFACEDESC);
ddsd.dwFlags = DDSD_WIDTH | DDSD_HEIGHT |DDSD_CAPS | DDSD_ZBUFFERBITDEPTH;
ddsd.dwHeight = height;
ddsd.dwWidth = width;
ddsd.dwZBufferBitDepth = bpp;
ddsd.ddsCaps.dwCaps = DDSCAPS_ZBUFFER | DDSCAPS_SYSTEMMEMORY;

err = dd->CreateSurface(&ddsd, &ZBuffer, 0);
if(err != DD_OK)
{
return FALSE;
}

err = BackBuffer->AddAttachedSurface(ZBuffer);

if(err != DD_OK)
{
return FALSE;
}

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Dance with me......