Draw transparent bitmap on canvas (Delphi 2007)

Hi,

I use quickpdf for a long time and directly draw to quickpdf canvas. Everything works except drawing transparent bitmaps.

I tried so far:

Using bitmap with pf1bit, pf8bit, pf24bit

1. Canvas.StretchDraw: copymode cmSRCAND, cmSRCCOPY will paint a complete black box). Brush is set to bsclear, clwhite. Explicit set transparentcolor has no effect. It works perfect on almost any printer canvas!

2. Using StretchDIBits will paint the bitmap but not transparent. Again, I tried transparentcolor, different brush styles, copymodes.  It works perfect on almost any printer canvas!

3. Using famous Joe Hecht solution for drawing bitmaps on a canvas ignores transparent color. It works perfect on almost any printer canvas!

After so many tries it seems to make no sense to publish source. My hope is, that someone successfully draw transparent bitmaps to quickpdf canvas.

4. One of the many other not working examples: SetBkColor, BitBlt…

Thanks...