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| Hello All!! Any help for a programmer in the little woods of Rochester?? I can display several transparent bitmaps onto the screen canvas, but when it comes to printing... It is a different story! I use Microsoft's DrawTransparentBitmap routine to display the graphics onto the screen. And I tried the same thing for printing and nothing comes out but black boxes. I have taken care of the stretching and coloring before I get to the routine. Any ideas or suggestion would be greatly appreciated! The Crew. This is part of the routine to get it ready to print... theBMP := TBitmap.Create ; theStretch := TBitmap.Create ; theBMP.Width := Round((PictItem^.Width)*widthDiff) ; theBMP.Height := Round((PictItem^.Height)*heightDiff) ; try theStretch.LoadFromFile(PictPath) ; {*** This puts in the palette to keep high-resolution bitmaps clear ***} SelectPalette(theBMP.Canvas.Handle, frmCalMain.imgLogo.Picture.Bitmap.Palette, True) ; SetStretchBltMode(theBMP.Canvas.Handle, STRETCH_DELETESCANS) ; {*** First stretch before displaying picture (the work-around for Win95) ***} StretchBlt(theBMP.Canvas.Handle, 0, 0, Round((PictItem^.Width)*widthDiff), Round((PictItem^.Height)*heightDiff), theStretch.Canvas.Handle, 0, 0, theStretch.Width, theStretch.Height, SRCCOPY); {*** Now draw the transparent picture onto the printer ***} DrawTransparentBitmap(Printer.Canvas, theBMP, Round((PosX-borderPosL)*widthDiff), Round((PosY-borderPosT)*heightDiff), clOlive) ; finally theBMP.Free ; theStretch.Free ; end ; If I do the above onto the screen canvas, no problem, but to the printer.... Sorry, no cigar! Here is the routine to draw transparent bitmaps: procedure DrawTransparentBitmap(Canvas : TCanvas ; BMP : TBitmap ; xStart, yStart : Integer ; cTransparentColor : LongInt) ; var bm : WinTypes.TBitmap ; cColor : TColorRef ; bmAndBack, bmAndObject, bmAndMem, bmSave, oldBmp : HBITMAP ; bmBackOld, bmObjectOld, bmMemOld, bmSaveOld, hBmp : HBITMAP ; hdcMem, hdcBack, hdcObject, hdcTemp, hdcSave, dc : HDC ; ptSize : WinTypes.TPoint ; temp_bitmap : TBitmap ; begin temp_bitmap := TBitmap.Create; temp_bitmap.Assign(bmp); try dc := Canvas.Handle; hBmp := Temp_Bitmap.Handle; hdcTemp := CreateCompatibleDC(dc); oldBmp := SelectObject(hdcTemp, hBmp); GetObject(hBmp, SizeOf(bm), @bm); ptSize.x := bm.bmWidth ; ptSize.y := bm.bmHeight ; hdcBack := CreateCompatibleDC(dc); hdcObject := CreateCompatibleDC(dc); hdcMem := CreateCompatibleDC(dc); hdcSave := CreateCompatibleDC(dc); bmAndBack := CreateBitmap(ptSize.x, ptSize.y, 1, 1, nil); bmAndObject := CreateBitmap(ptSize.x, ptSize.y, 1, 1, nil); bmAndMem := CreateCompatibleBitmap(dc, ptSize.x, ptSize.y); bmSave := CreateCompatibleBitmap(dc, ptSize.x, ptSize.y); bmBackOld := SelectObject(hdcBack, bmAndBack); bmObjectOld := SelectObject(hdcObject, bmAndObject); bmMemOld := SelectObject(hdcMem, bmAndMem); bmSaveOld := SelectObject(hdcSave, bmSave); SetMapMode(hdcTemp, GetMapMode(dc)); BitBlt(hdcSave, 0, 0, ptSize.x, ptSize.y, hdcTemp, 0, 0, SRCCOPY); cColor := SetBkColor(hdcTemp, cTransparentColor); BitBlt(hdcObject, 0, 0, ptSize.x, ptSize.y, hdcTemp, 0, 0, SRCCOPY); SetBkColor(hdcTemp, cColor); BitBlt(hdcBack, 0, 0, ptSize.x, ptSize.y, hdcObject, 0, 0, NOTSRCCOPY); BitBlt(hdcMem, 0, 0, ptSize.x, ptSize.y, dc, xStart, yStart, SRCCOPY); BitBlt(hdcMem, 0, 0, ptSize.x, ptSize.y, hdcObject, 0, 0, SRCAND); BitBlt(hdcTemp, 0, 0, ptSize.x, ptSize.y, hdcBack, 0, 0, SRCAND); BitBlt(hdcMem, 0, 0, ptSize.x, ptSize.y, hdcTemp, 0, 0, SRCPAINT); BitBlt(dc, xStart, yStart, ptSize.x, ptSize.y, hdcMem, 0, 0, SRCCOPY); BitBlt(hdcTemp, 0, 0, ptSize.x, ptSize.y, hdcSave, 0, 0, SRCCOPY); DeleteObject(SelectObject(hdcBack, bmBackOld)); DeleteObject(SelectObject(hdcObject, bmObjectOld)); DeleteObject(SelectObject(hdcMem, bmMemOld)); DeleteObject(SelectObject(hdcSave, bmSaveOld)); SelectObject(hdcTemp, oldBmp); DeleteDC(hdcMem); DeleteDC(hdcBack); DeleteDC(hdcObject); DeleteDC(hdcSave); DeleteDC(hdcTemp); finally Temp_Bitmap.Free; end ; end; ----------------------------------------------------------------------------- Re: Printing differences between NT and Win95??? Actually we did find the error i TPrinter, and have resolved it into this wrapper function, it works, but the transparency problem still persists in this version. Do anyone have any suggestions? procedure THSPrinter.PrintBitmap(Bitmap: Graphics.TBitmap; X, Y, pWidth, pHeight: Integer); var Info : PBitmapInfo; InfoSize : Integer; Image : Pointer; {$IFDEF WIN32} ImageSize: DWord; {$ELSE} ImageSize: LongInt; {$ENDIF} R: Real; PrinterHeight, PrinterWidth: Integer; begin if (pWidth<1) or (pHeight<1) then begin pWidth:= Bitmap.Width; pHeight:= Bitmap.Height; end; with Bitmap do begin GetDIBSizes (Handle,InfoSize,ImageSize); Info:= MemAlloc(InfoSize); try Image:= GlobalAllocPtr(HeapAllocFlags,ImageSize); try GetDIB(Handle,Palette,Info^,Image^); R:= Info^.bmiHeader.biWidth; R:= R/Info^.bmiHeader.biHeight; PrinterWidth:= Trunc (pHeight*R); if PrinterWidth>pWidth then begin PrinterWidth:= pWidth; PrinterHeight:= Trunc (PrinterWidth/R); end else PrinterHeight:= pHeight; with Info^.bmiHeader do StretchDIBits (Printer.Canvas.Handle,(pWidth-PrinterWidth) DIV 2, (pHeight-PrinterHeight) DIV 2,PrinterWidth,PrinterHeight, X,Y,X+biWidth,Y+biHeight,Image,Info^,DIB_RGB_COLORS,SRCCOPY); finally GlobalFreePtr(Image); end; finally FreeMem (Info,InfoSize); end; end; end; Davie Reed wrote: > I have been told that this is an old issue. It seems that the TPrinter > module in Delphi has PROBLEMS in it. And that you can NOT relaibly use the > DRAW or STRETCHDRAW :( > > So, instead you can use the StretchDiBits funtion to draw/stretch to the > printer canvas's DC. > > Davie > > Stig Bircherod Calundan wrote: > > > We have a problem when we print bitmaps on Win95 + 98, but not on NT4, > > the problem consists of the white part of a bitmap, which NT interprets > > as transparent (thas ok), but on Win95 the white part is painted as a > > gray area. The intensity of the graying is different on different > > printers, though color printers does interpret the white area correctly. > > > > The bitmaps is loaded into a TBitmap using abitmap.handle:= loadbitmap > > (...), and is later drawn to the printers canvas, with the canvas.draw > > command. > > > > The printer used on both Win95 and NT is a HP LaserJet 5Si/5Si MX PS > > with the latest printer drivers... > > > > Please help.... > > > > Stig |
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