[VB6] - How apture a window or Picturebox?

[joaquim]

i have seen very api functions for capture a window or picturebox, but all are slow for animation.
anyone knows any function that can do it with some speed?

[joaquim]

ok... i found 1 nice way(these code is in module):

Option Explicit


'This call gives us the hWnd (window handle) of the screen
Private Declare Function GetDesktopWindow Lib "user32" () As Long

'This call assigns an hDC (handle of device context) from an hWnd
Private Declare Function GetDC Lib "user32" (ByVal hWnd As Long) As Long

'BitBlt lets us draw an image from a hDC to another hDC (in our case, from an hDC of the screen capture to the hDC of a VB picture box)
Private Declare Function BitBlt Lib "gdi32" (ByVal hDC As Long, ByVal x As Long, ByVal y As Long, ByVal nWidth As Long, ByVal nHeight As Long, ByVal hSrcDC As Long, ByVal xSrc As Long, ByVal ySrc As Long, ByVal opCode As Long) As Long

'ReleaseDC will be used to clear out the hDC we generate for the screen capture.
Private Declare Function ReleaseDC Lib "user32" (ByVal hWnd As Long, ByVal hDC As Long) As Long

'Sample: PrintWindowWithControls picturedestany.hdc, picturesource.hwnd, 0, 0, picturesource.width, picturesource.width
Public Sub PrintWindowWithControls(PictureDestany As Long, PictureSource As Long, Optional PositionX As Long = 0, Optional PositionY As Long = 0, Optional Width As Long = 0, Optional Height As Long = 0)
    'PictureDestany.Picture = Nothing
    'Get the hWnd of the screen
    Dim scrHwnd As Long
    scrHwnd = PictureSource
    
    'Now, assign an hDC to the hWnd we generated
    Dim shDC As Long
    shDC = GetDC(scrHwnd)
    
    'Determine the size of the screen
    'Dim screenWidth As Long, screenHeight As Long
    'screenWidth = Screen.Width \ Screen.TwipsPerPixelX
    'screenHeight = Screen.Height \ Screen.TwipsPerPixelY
   
    'Copy the pixel data from the screen into our form
    BitBlt PictureDestany, PositionX, PositionY, Width, Height, shDC, 0, 0, vbSrcCopy
        
    'Release our hold on the screen DC
    ReleaseDC scrHwnd, shDC
    
End Sub

heres how we use it:
PrintWindowWithControls picturedestany.hdc, picturesource.hwnd, 0, 0, picturesource.width, picturesource.width
(the code isn't completed, but works)
i have 2 questions:
1 - what it's the diference between these bitblt() to normal\standard bitblt()?
2 - instead bitblt(), can i use the Stritchblt() or Transparentblt() api functions?