Вопрос прорисовки из оперативной памяти DIB

Private Type BITMAPINFOHEADER '40 bytes
   biSize As Long
   biWidth As Long
   biHeight As Long
   biPlanes As Integer
   biBitCount As Integer
   biCompression As Long
   biSizeImage As Long
   biXPelsPerMeter As Long
   biYPelsPerMeter As Long
   biClrUsed As Long
   biClrImportant As Long
End Type
Private Declare Sub CopyMemory Lib "kernel32.dll" Alias "RtlMoveMemory" (ByRef dest As Any, ByRef src As Any, ByVal dwLen As Long)
Private m_memBits() As Byte
Private m_memBitmapInfo() As Byte
Private m_bih As BITMAPINFOHEADER
Private m_bfh As BITMAPFILEHEADER
Public Function CreateFromPackedDIBPointer(ByRef pDIB As Long) As Boolean
Debug.Assert pDIB <> 0
'Creates a full-color (no palette) DIB from a pointer to a full-color memory DIB
 
'get the BitmapInfoHeader
Call CopyMemory(ByVal VarPtr(m_bih.biSize), ByVal pDIB, Len(m_bih))
If m_bih.biBitCount < 16 Then
    Debug.Print 'Error! DIB was less than 16 colors.'
    Exit Function 'only supports high-color or full-color dibs
End If
 
'now get the bitmap bits
If m_bih.biSizeImage < 1 Then Exit Function 'return False
ReDim m_memBits(0 To m_bih.biSizeImage - 1)
Call CopyMemory(m_memBits(0), ByVal pDIB + 40, m_bih.biSizeImage)
 
'and BitmapInfo variable-length UDT
ReDim m_memBitmapInfo(0 To 39) 'don't need first 14 bytes (fileinfo)
Call CopyMemory(m_memBitmapInfo(0), m_bih, Len(m_bih))
 
'create a file header
With m_bfh
    .bfType = BMP_MAGIC_COOKIE
    .bfSize = 55 + m_bih.biSizeImage 'size of file as written to disk
    .bfReserved1 = 0&
    .bfReserved2 = 0&
    .bfOffBits = 54 'BitmapInfoHeader + BitmapFileHeader
End With
 
'and return True
CreateFromPackedDIBPointer = True
 
End Function
 
В массиве m_memBits хранятся поочередно цвета, т.е. можно прорисовать следующим образом:
 ni = 0
 For yy = 0 To m_bih.biHeight - 1
   For xx = 0 To m_bih.biWidth - 1
   SetPixel frmStart.Picture1.hdc, xx, yy, RGB(m_memBits(ni + 2), m_memBits(ni + 1), m_memBits(ni))
  ni = ni + 3
  Next xx
 Next yy