All these GUI elements have been created from a single CUniButton class. The unusual shapes produced by using windows regions. Regions have been introduced in Windows 95, so do not try do use CUniButton on Win 3.1. You can create button out of any shape you can think of. CUniButton class was built on top of MFC CButton class.
Region occupied by the button is specified in the constructor.
When there is time to paint button one of the prepared bitmaps is painted. Application of button region for clipping provides flicker free drawing. Corp. All Rights Reserved.