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Poor Man's Transparent Image Control

AlphaBlendImage control is built-in VB.Image control replacement (sort of) that supports alpha transparent images through GDI+. Standard OLE automation StdPicture objects can load 32-bit alpha transparent images in vbPicTypeIcon subtype, although few controls paint the alpha channel on these StdPictures. This AlphaBlendImage control brings this support.

The control's public GdipLoadPicture method can load 32-bit alpha transparent PNGs in StdPicture objects which can be assigned to control's Picture property. In the sample Form1 such alpha transparent image is loaded to a StdPicture and is assigned both to a built-in VB.Image control and to an AlphaBlendImage control to compare difference in output.

The control supports Opacity property for "global" control transparency level (in addition to per-pixel alpha).

The control supports MaskColor property for color-key transparency (in addition to per-pixel alpha).

The control supports Rotation property which rotates the assigned image (in degrees).

The control supports Zoom property which scales the image (only when Stretch is off).

The control is windowless and cannot get focus. Its AutoRedraw property controls if repaint is cached to memory 32-bit DIB for faster redraws.