DirectDraw

[DNA7433]

Dim DX As New DirectX7
Dim DD As DirectDraw7

Dim P As DirectDrawSurface7
Dim B As DirectDrawSurface7
Dim S As DirectDrawSurface7

Dim dP As DDSURFACEDESC2
Dim dB As DDSURFACEDESC2
Dim dS As DDSURFACEDESC2

Dim pos As Integer

Private Sub cmdOpen_Click()
    dS.lFlags = DDSD_CAPS
    dS.ddsCaps.lCaps = DDSCAPS_OFFSCREENPLAIN
    Set S = Nothing
    Set S = DD.CreateSurfaceFromFile(Text1.Text, dS)
    
    Dim Dest As RECT, Src As RECT
    
    Dest.Bottom = 241
    Dest.Left = 289 * pos - 289
    Dest.Right = 289 * pos
    
    Src.Right = dS.lWidth
    Src.Bottom = dS.lHeight
    
    B.Blt Dest, S, Src, DDBLT_WAIT
    
    P.Flip B, DDFLIP_WAIT
    
    pos = pos + 289
End Sub

Private Sub Form_Load()
    Set DD = DX.DirectDrawCreate("")

    dP.lFlags = DDSD_BACKBUFFERCOUNT Or DDSD_CAPS
    dP.ddsCaps.lCaps = DDSCAPS_FLIP Or DDSCAPS_COMPLEX Or DDSCAPS_PRIMARYSURFACE
    dP.lBackBufferCount = 1
    Set P = DD.CreateSurface(dP)
    
    Dim cap As DDSCAPS2
    cap.lCaps = DDSCAPS_BACKBUFFER
    Set B = P.GetAttachedSurface(cap)
    B.GetSurfaceDesc dP
    pos = 0
End Sub

Whats wrong with this code?
It says that Set P = DD.CreateSurface(dP) is wrong somehow during run-time
Im trying to make a frame editor for some animation for my other program.

[Sastraxi]

There are a few things wrong, although I dont know if these are related to the problem:

Pos = Pos + 289
289 * Pos(289) = BIG BIG NUMBER

Should be
Pos = Pos + 1
289 * 1 = 289
289 * 2 = 578
...etc.

And where do you attach the backbuffer?