/**
@class wxBufferedDC
@wxheader{dcbuffer.h}
-
+
This class provides a simple way to avoid flicker: when drawing on it,
everything is in fact first drawn on an in-memory buffer (a
wxBitmap) and then copied to the screen, using the
is typically associated with wxClientDC, if you want to
use it in your @c EVT_PAINT handler, you should look at
wxBufferedPaintDC instead.
-
+
When used like this, a valid @e dc must be specified in the constructor
while the @e buffer bitmap doesn't have to be explicitly provided, by
default this class will allocate the bitmap of required size itself. However
using a dedicated bitmap can speed up the redrawing process by eliminating the
repeated creation and destruction of a possibly big bitmap. Otherwise,
- wxBufferedDC can be used in the same way as any other device context.
-
+ wxBufferedDC can be used in the same way as any other device context.
+
There is another possible use for wxBufferedDC is to use it to maintain a
backing store for the window contents. In this case, the associated @e dc
may be @NULL but a valid backing store bitmap should be specified.
-
+
Finally, please note that GTK+ 2.0 as well as OS X provide double buffering
- themselves natively. You can either use wxWindow::IsDoubleBuffered
- to determine whether you need to use buffering or not, or use
+ themselves natively. You can either use wxWindow::IsDoubleBuffered
+ to determine whether you need to use buffering or not, or use
wxAutoBufferedPaintDC to avoid needless double
buffering on the systems which already do it automatically.
-
+
@library{wxcore}
@category{dc}
-
+
@seealso
wxDC, wxMemoryDC, wxBufferedPaintDC, wxAutoBufferedPaintDC
*/
public:
//@{
/**
- If you use the first, default, constructor, you must call one of the
+ If you use the first, default, constructor, you must call one of the
Init() methods later in order to use the object.
- The other constructors initialize the object immediately and @c Init()
+ The other constructors initialize the object immediately and @c Init()
must not be called after using them.
- @param dc
+ @param dc
The underlying DC: everything drawn to this object will be
flushed to this DC when this object is destroyed. You may pass @NULL
in order to just initialize the buffer, and not flush it.
- @param area
+ @param area
The size of the bitmap to be used for buffering (this bitmap is
created internally when it is not given explicitly).
- @param buffer
+ @param buffer
Explicitly provided bitmap to be used for buffering: this is
the most efficient solution as the bitmap doesn't have to be recreated each
time but it also requires more memory as the bitmap is never freed. The bitmap
should have appropriate size, anything drawn outside of its bounds is clipped.
- @param style
+ @param style
wxBUFFER_CLIENT_AREA to indicate that just the client area of
the window is buffered, or wxBUFFER_VIRTUAL_AREA to indicate that the buffer
bitmap
device context).
*/
wxBufferedDC();
- wxBufferedDC(wxDC * dc, const wxSize& area,
- int style = wxBUFFER_CLIENT_AREA);
- wxBufferedDC(wxDC * dc, wxBitmap& buffer,
- int style = wxBUFFER_CLIENT_AREA);
+ wxBufferedDC(wxDC * dc, const wxSize& area,
+ int style = wxBUFFER_CLIENT_AREA);
+ wxBufferedDC(wxDC * dc, wxBitmap& buffer,
+ int style = wxBUFFER_CLIENT_AREA);
//@}
/**
*/
void Init(wxDC * dc, const wxSize& area,
int style = wxBUFFER_CLIENT_AREA);
- void Init(wxDC * dc, wxBitmap& buffer,
- int style = wxBUFFER_CLIENT_AREA);
+ void Init(wxDC * dc, wxBitmap& buffer,
+ int style = wxBUFFER_CLIENT_AREA);
//@}
};
/**
@class wxAutoBufferedPaintDC
@wxheader{dcbuffer.h}
-
+
This wxDC derivative can be used inside of an @c OnPaint() event handler to
achieve
double-buffered drawing. Just create an object of this class instead of
with wxBG_STYLE_CUSTOM somewhere in the class initialization code, and that's
all you have
to do to (mostly) avoid flicker.
-
+
The difference between wxBufferedPaintDC and this class,
is the lightweigthness - on platforms which have native double-buffering,
wxAutoBufferedPaintDC is simply
a typedef of wxPaintDC. Otherwise, it is a typedef of wxBufferedPaintDC.
-
+
@library{wxbase}
@category{dc}
-
+
@seealso
wxDC, wxBufferedPaintDC
*/
/**
@class wxBufferedPaintDC
@wxheader{dcbuffer.h}
-
+
This is a subclass of wxBufferedDC which can be used
inside of an @c OnPaint() event handler. Just create an object of this class
instead
using this class together with wxScrolledWindow, you probably
do @b not want to call wxScrolledWindow::PrepareDC on it as it
already does this internally for the real underlying wxPaintDC.
-
+
@library{wxcore}
@category{dc}
-
+
@seealso
wxDC, wxBufferedDC, wxAutoBufferedPaintDC
*/
*/
wxBufferedPaintDC(wxWindow * window, wxBitmap& buffer,
int style = wxBUFFER_CLIENT_AREA);
- wxBufferedPaintDC(wxWindow * window,
- int style = wxBUFFER_CLIENT_AREA);
+ wxBufferedPaintDC(wxWindow * window,
+ int style = wxBUFFER_CLIENT_AREA);
//@}
/**