hBmp & Printer

[Semen Matusovski]

Hi, guys --
Easy question, but ...
There is pd As PRINTDLGAPI, received by PrintDlg(pd), and "free" true-colour hBmp.

I have troubles with following

     Local hBmpDC As Long
     hBmpDC = CreateCompatibleDC(pd.hDC)
     SelectObject hBmpDC, hMemBmp
     BitBlt pd.hDC, 0, 0, _
         rcfConsole.nRight - rcfConsole.nLeft, rcfConsole.nBottom - rcfConsole.nTop, _
         hBmpDC, 0, 0, %SRCCOPY

Return values are correct, and even a printer is color.
Print job appears, but without my picture.

At the same time

      Local pdHDC As Long
      pDhDC = GetWindowDC(GetDesktopWindow)
      hBmpDC = CreateCompatibleDC(pdhDC)
      SelectObject hBmpDC, hMemBmp
      BitBlt pdhDC, 0, 0, _
         rcfConsole.nRight - rcfConsole.nLeft, rcfConsole.nBottom - rcfConsole.nTop, _
         hBmpDC, 0, 0, %SRCCOPY)
      ReleaseDC GetDesktopWindow, pdHdc

works fine on the screen.

What am I doing wrong ?

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E-MAIL: [email protected]

[Don Dickinson]

BitBlt does not always work with printers unless the bitmap is monochrome. Sometimes it will work, sometimes not.
You have to use a DIB to print reliably to windows printers. This brings up some issues of palettes, etc and gets a little complicated.
If you search the code area for DIB you'll probably find some code.

Best Regards,
Don

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[Semen Matusovski]

Don --
I want to avoid direct copying from screen hDC to printer hDC (BTW, which works fine on my PC).

I read a recommendation to do following -
1) Create printer-compatible memory DC (hPrDC).
2) Create printer-compatible hPrBmp.
3) Select hPrBmp into hPrDC (clear), copy "screen" bitmap into hPrBmp (???) and then copy that bitmap to the printer DC.

I can't understand p.3.
Really I have no screen hBmp, I build it from window hDC.

     ' Prepare screen bitmap (hMemBmp)
      bmi.bmiHeader.biSize = SizeOf(bmi.bmiHeader)
      bmi.bmiHeader.biWidth = (rcfConsole.nRight - rcfConsole.nLeft)
      bmi.bmiHeader.biHeight = (rcfConsole.nBottom - rcfConsole.nTop)
      bmi.bmiHeader.biPlanes = 1
      bmi.bmiHeader.biBitCount =   24
      bmi.bmiHeader.biCompression = %BI_RGB
      hMemDC = CreateCompatibleDC (hConsoleDC)
      hMemBmp = CreateDIBSection(hMemDC, bmi, %DIB_RGB_COLORS, 0, 0, 0)

hConsoleDC is hDC of screen window.
After filling hMemDC and some additional actions, I have "free" hBmp and is able to select it into another screen compatible hDC.

Now I try to follow p.3 of recommendations (but w/o sample).

How to understand (to translate to API) -
1) copy bitmap, which you want to Print, (hMemBmp) into hPrBmp (???) and
2) then copy that bitmap to the printer DC.


[This message has been edited by Semen Matusovski (edited November 01, 2000).]

[Borje Hagsten]

Just a silly idea, but.. have you tried using StretchBlt instead
of BitBlt? A tip: there's a sample under "Printing a Document" in
win32.api.hlp that shows how print a string of text and a bitmapped
image, by using StretchBlt. Could be useful to look at..


------------------

[Semen Matusovski]

Borje --
Thanks, but alone, which I saw
If (!StretchBlt(pd.hDC, ... errhandler("StretchBlt Failed", hwnd)

I have no troubles on my PC, when I copy screen hDC to printer hDC.
But theoretically users can have.

I'm interesting, what to do if GetDeviceCaps (RC_BITBLT and RC_STRETCHBLT) shows that such operations ARE NOT AVAILABLE.

What gues do you think about following way (I can't imitate situation)
1) To create 24-bits DIB section, compatible with printer DC.
To select it into Printer DC.
2) Instead of BitBlt (stretchBlt), to copy all "pixels" directly from DIB-section, compatible with screen.
Does this solve a problem or not ?

[This message has been edited by Semen Matusovski (edited November 01, 2000).]

[Borje Hagsten]

Hm, if you have the bitmap created that way, maybe you can try
StretchDIBits() instead? I once had to do this in a print preview
function in an earlier version of my software, because StretchBlt
failed to work properly with some grafik cards and printers.
StretchDIBits turned out to be a little bit slower but seemed to
work better. At least I got fewer support calls after I started
using it instead..


------------------

[Don Dickinson]

The bottom line is that you can't rely on bitblt or stretchblt to copy a bitmap to a printer. By definition, these work on device dependent bitmaps. They might work, but there is no guarantee.
You have to use some sort of DIB operation (like StretchDIBits as suggested by Borje). Before doing this, you must create a dib. It looks like you might be going in the right direction with CreateDIBSection - that's one way to get a dib from a bitmap. I'm not familiar with the details of this approach, though.

Best Regards,
Don

------------------

[Semen Matusovski]

Guys --
What I currently do ... (note PB/CC; console should be in window)

   #Compile Exe
   #Register None
   #Dim All
   #Include "Win32Api.Inc"
   #Include "ComDlg32.Inc"

   $FileBmp = "C:\WinNt\WinNt.bmp" ' <---------- CHANGE

   Global hWndConsole As Long, hConsoleDC As Long, rcfConsole As RECT


   Function GetDefaultPrinterDC As Long

      Dim PrinterName As Asciiz * %MAX_PATH

      GetProfileString "WINDOWS", "DEVICE", ",,,", PrinterName, SizeOf(PrinterName)
      PrinterName = Left$(PrinterName, Instr(PrinterName$, ",") - 1)
      If PrinterName = "" Then Exit Function
      Function = CreateDC(ByVal %Null, PrinterName$, ByVal %Null, ByVal %Null)

   End Function

   Sub GetConsoleDCRC
      Dim pt As POINTAPI

      hConsoleDC = GetWindowDC(hWndConsole)
      GetWindowRect hWndConsole, rcfConsole
      ClientToScreen hWndConsole, pt
      pt.x = pt.x - rcfConsole.nLeft
      pt.y = pt.y - rcfConsole.nTop
      GetClientRect hWndConsole, rcfConsole
      rcfConsole.nLeft   = rcfConsole.nLeft + pt.x
      rcfConsole.nRight  = rcfConsole.nRight + pt.x
      rcfConsole.nTop    = rcfConsole.nTop + pt.y
      rcfConsole.nBottom = rcfConsole.nBottom + pt.y

   End Sub

   Function PrintConsoleWindow As Long

      GetConsoleDCRC
      Local hMemDC As Long, hMemBmp As Long, hMemBmpOld As Long, bmi As BITMAPINFO, bm As BITMAP

      ' Prepare screen bitmap (hMemBmp)
      bmi.bmiHeader.biSize = SizeOf(bmi.bmiHeader)
      bmi.bmiHeader.biWidth = (rcfConsole.nRight - rcfConsole.nLeft)
      bmi.bmiHeader.biHeight = (rcfConsole.nBottom - rcfConsole.nTop)
      bmi.bmiHeader.biPlanes = 1
      bmi.bmiHeader.biBitCount =   24
      bmi.bmiHeader.biCompression = %BI_RGB
      hMemDC = CreateCompatibleDC (hConsoleDC)
      hMemBmp = CreateDIBSection(hMemDC, bmi, %DIB_RGB_COLORS, 0, 0, 0)
      GlobalLock hMemBmp
      hMemBmpOld = SelectObject (hMemDC, hMemBmp)
      GetObject hMemBmp, SizeOf(bm), bm
      BitBlt hMemDC, 0, 0, bm.bmWidth, bm.bmHeight, hConsoleDC, rcfConsole.nLeft, rcfConsole.nTop, %SRCCOPY
      SelectObject hMemDC, hMemBmpOld
      DeleteDC hMemDC

      '----------
      Local hPrDC   As Long
      Local di     As DOCINFO
      Local dn     As Asciiz * 64

      hPrDC = GetDefaultPrinterDC

      If hPrDC Then
         Local hBmpDC As Long

         Local x      As Long
         Local y      As Long

         x = GetDeviceCaps(hPrDC, %HORZRES)
         y = CLng((x / (rcfConsole.nRight - rcfConsole.nLeft)) * (rcfConsole.nBottom - rcfConsole.nTop))

         dn = "Ltr"
         di.cbSize = SizeOf(di)
         di.lpszDocName = VarPtr(dn)

         ' scale the bitmap to the width of the page
         hBmpDC   = CreateCompatibleDC(hPrDC)
         SelectObject hBmpDC, hMemBmp

         If StartDoc(hPrDC, di) > 0 Then
            If StartPage(hPrDC) > 0 Then
               StretchBlt hPrDC, 0, 0, x, y, hBmpDC, 0, 0, rcfConsole.nRight - rcfConsole.nLeft, _
                 rcfConsole.nBottom - rcfConsole.nTop, %SRCCOPY
               EndPage hPrDC
            End If
            EndDoc hPrDC
         End If

         DeleteDC hPrDC
         DeleteDC hBmpDC

      End If

      DeleteObject hMemBmp
      ReleaseDc hWndConsole, hConsoleDC

    End Function


   Function PbMain

      hWndConsole = GetForegroundWindow

      GetConsoleDCRC

      Local hBmp As Long, hBmpDC As Long
      hBmp = LoadImage(ByVal %NULL, $FileBmp, %IMAGE_BITMAP, _
         rcfConsole.nRight - rcfConsole.nLeft, rcfConsole.nBottom - rcfConsole.nTop, %LR_LOADFROMFILE)
      hBmpDC = CreateCompatibleDC(hConsoleDC)
      SelectObject hBmpDC, hBmp
      BitBlt hConsoleDC, rcfConsole.nLeft, rcfConsole.nTop, _
         rcfConsole.nRight - rcfConsole.nLeft, rcfConsole.nBottom - rcfConsole.nTop, _
         hBmpDC, 0, 0, %SRCCOPY
      DeleteDC hBmpDC
      ReleaseDc hWndConsole, hConsoleDC

      Local i As Long
      For i = 1 To 10
         Locate 2 + i, 10: Print "      Line       " + Format$(i, "00") + "             "
      Next

      PrintConsoleWindow

   End Function

This works on my PC under 2000 and 98, color and black/white printing.
But something confuses me.
I decided that to build true color DIB section for printer DC is too expensive (too many dots).
Alone, what I do - I select DIB section into printer-compatible DC.

Guys, somebody have problems with this code (under any OS, with network printers and so on) ?



------------------
E-MAIL: [email protected]

[Jeffrey R. Radue]

Semen, a couple of comments on the CreateDIBSection function.
I am far from an expert on Windows bitmaps, but ....

1. I'm not sure your dibsection is getting any bits. The documentation
suggests that you need to set a long variable by ref in the lplpvoid field. This
will contain the bitmap data of the dibsection. Then, you use a
stretchblt command passing the data pointer.

2. The declaration in the win32api file uses byval lplpvoid as long. This
will not work since only the temporary copy of the variable will be initialized.
Apparently this function creates its own memory block to contain the bit data.
So,you need to retrieve the pointer value from the function. BTW, this is not PB's
problem, apparently Microsoft orginally declared the function this way.

Jeff


------------------

[Dominic Mitchell]

Jeffrey,
The win32api declaration is correct. Semen used an indirect method to
get the bitmap bits. The direct method is to call CreateDIBSection as follows-

  LOCAL     pbBits        AS BYTE PTR

  ' Create the destination bitmap(a 24 bpp top down dib)
  ' ----------------------------------------------------
  hDCDest    = CreateCompatibleDC(hDC)
  ' Calculate bytes per scan line
  cblPerLine = ((cxPaint * 3 + 3) \ 4) * 4
  cblImage   = cblPerLine * cyPaint
  tbmi.bmiHeader.biSize         = SIZEOF(tbmi.bmiHeader)
  tbmi.bmiHeader.biWidth        = cxPaint
  tbmi.bmiHeader.biHeight       = -cyPaint
  tbmi.bmiHeader.biPlanes       = 1
  tbmi.bmiHeader.biBitCount     = 24
  tbmi.bmiHeader.biCompression  = %BI_RGB
  tbmi.bmiHeader.biSizeImage    = cblImage
  tbmi.bmiHeader.biClrUsed      = 0
  tbmi.bmiHeader.biClrImportant = 0
  hDIB = CreateDIBSection(hDCDest, tbmi, %DIB_RGB_COLORS, VARPTR(pbBits), %NULL, 0)

------------------
Dominic Mitchell

[This message has been edited by Dominic Mitchell (edited November 01, 2000).]