Cutting edge: Context-Sensitive PictureBox Controls

摘要

Great ideas are timeless. A long time ago in Microsoft Systems Journal Paul DiLascia demonstrated a neat trick to display context-sensitive tooltips floating over pictures (see microsoft.com/ msj/0397/c/c0397.aspx). As the user moved the mouse over the picture, the tooltip control updated its text to reflect the name of the pointed figure. How can a tooltip control be smart enough to support a non-rectangular area that, for example, precisely follows the natural shape of a human figure in a painting? Hot spots in images are nothing new, but you normally define them through common, easy-to-de-scribe shapes—rectangles, circles, or perhaps polygons.