- A wxDC is a @e device context onto which graphics and text can be drawn.
- It is intended to represent a number of output devices in a generic way,
- so a window can have a device context associated with it, and a printer also
- has a device context.
- In this way, the same piece of code may write to a number of different devices,
- if the device context is used as a parameter.
-
- Notice that wxDC is an abstract base class and can't be created directly,
- please use wxPaintDC, wxClientDC,
- wxWindowDC, wxScreenDC,
- wxMemoryDC or wxPrinterDC.
-
- Please note that in addition to the versions of the methods documented here,
- there are also versions which accept single @c wxPoint parameter instead of
- two @c wxCoord ones or @c wxPoint and @c wxSize instead of four of
- them.
+ A wxDC is a @e "device context" onto which graphics and text can be drawn.
+ It is intended to represent different output devices and offers a common
+ abstract API for drawing on any of them.
+
+ wxWidgets offers an alternative drawing API based on the modern drawing
+ backends GDI+, CoreGraphics and Cairo. See wxGraphicsContext, wxGraphicsRenderer
+ and related classes. There is also a wxGCDC linking the APIs by offering
+ the wxDC API ontop of a wxGraphicsContext.
+
+ wxDC is an abstract base class and cannot be created directly.
+ Use wxPaintDC, wxClientDC, wxWindowDC, wxScreenDC, wxMemoryDC or
+ wxPrinterDC.
+
+ In addition to the versions of the methods documented below, there
+ are also versions which accept single wxPoint parameter instead
+ of the two wxCoord ones or wxPoint and wxSize instead of the four
+ wxCoord parameters.
+
+ Beginning with wxWidgets 2.9.0 the entire wxDC code has been
+ reorganized. All platform dependent code (actually all drawing code)
+ has been moved into backend classes which derive from a common
+ wxDCImpl class. The user-visible classes such as wxClientDC and
+ wxPaintDC merely forward all calls to the backend implementation.
+
+ On Mac OS X colours with alpha channel are supported. Instances wxPen
+ or wxBrush that are built from wxColour use the colour's alpha values
+ when stroking or filling.