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I want to draw quite complex images with alpha-transparent rectangles and alpha-transparent images. There is GDI+ wrapper from Mitov , but it doesn't seem to support 32bit BMP files plus it rescales them and the documentation is terrible. BMPs are way faster than PNGs so I want to use them. There is SynGDI wrapper of GDI+ , but it seems very basic and there is no documentation for it. There is also this trick for GDI: procedure DrawAlphaAPI(Source: TBitmap; Destination: TCanvas; const X, Y: Integer; const Opacity: Byte = 255); var BlendFunc: TBlendFunction; begin BlendFunc.BlendOp := AC_SRC_OVER; BlendFunc.BlendFlags := 0; BlendFunc.SourceConstantAlpha := Opacity; if Source.PixelFormat = pf32bit then BlendFunc.AlphaFormat := AC_SRC_ALPHA else BlendFunc.AlphaFormat := 0; Windows.AlphaBlend(Destination.Handle, X, Y, Source.Width, Source.Height, Source.Canvas.Handle, 0, 0, Source.Width, Source.Height, BlendFunc); end; But when I call it with Opacity = 255 it draws 32bit bitmaps not properly (something like they are half transparent where they should be fully). I don't want to use Scanline to make pixels transparent as this will be too complicated to draw all the transparent rectangles this way. Also I thin GDI+ should be faster on modern computers, am I right? So the question is: how to draw an alpha transparent rectangle and bitmap easily (without tons of code)? Preferred Delphi: 7. I also have 2005 and XE3 but since 7 is a speed demon I would most want something to work from 7 up.

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