How do you do both blending and transparency using just pure VCL on bitmapped images?
问题 Similar to this question I would like to both blend colors, and bitmaps (png or bmp, but in my case I'm using a png) while preserving transparency. As with the linked question, I would like to (a) not use third party libraries, (b) use VCL built in techniques where possible but with recourse to the Win32 GDI APIs where needed, and (c) not use GDI+. This simple code, based on the code in the linked question I see that the color blending works but the PNG file's transparency is not preserved,