wx.GCDC is a device context that draws on a wx.GraphicsContext.
wx.GCDC does its best to implement wx.DC API, but the following features are not (fully) implemented because wx.GraphicsContext doesn’t support them:
GetPixel
method is not implemented and always returns False
because modern graphics layers don’t support retrieving the contents of the drawn pixels.
FloodFill
method is not, and can’t be, implemented, as its functionality relies on reading the pixels from wx.GraphicsContext too.
SetLogicalFunction
method only works with COPY
, OR
, NO_OP
, CLEAR
and XOR
functions, attempts to use any other function (including INVERT
) don’t do anything.
Similarly, wx.RasterOperationMode parameter of Blit
and StretchBlit
can only be one of the supported logical functions listed above, using any other function will result in an assertion failure and not drawing anything.
For Direct2D-based wx.GraphicsContext, only true-type fonts can be used in the font-related functions.
See also
Constructs a wx.GCDC from a wx.WindowDC. |
|
Retrieves associated wx.GraphicsContext. |
|
Set the graphics context to be used for this wx.GCDC. |
See |
wx.
GCDC
(DC)¶Possible constructors:
GCDC(windowDC)
GCDC(memoryDC)
GCDC(printerDC)
GCDC(context)
GCDC()
GCDC is a device context that draws on a GraphicsContext.
__init__
(self, *args, **kw)¶__init__ (self, windowDC)
Constructs a wx.GCDC from a wx.WindowDC.
windowDC (wx.WindowDC) –
__init__ (self, memoryDC)
Constructs a wx.GCDC from a wx.MemoryDC.
memoryDC (wx.MemoryDC) –
__init__ (self, printerDC)
Constructs a wx.GCDC from a wx.PrinterDC.
printerDC (wx.PrinterDC) –
__init__ (self, context)
Construct a wx.GCDC from an existing graphics context.
Note that this object takes ownership of context and will delete it when it is destroyed or when SetGraphicsContext
is called with a different context object.
Also notice that context will continue using the same font, pen and brush as before until SetFont
, SetPen
or SetBrush
is explicitly called to change them. This means that the code can use this DC-derived object to work using pens and brushes with alpha component, for example (which normally isn’t supported by wx.DC API), but it also means that the return values of GetFont
, GetPen
and GetBrush
won’t really correspond to the actually used objects because they simply can’t represent them anyhow. If you wish to avoid such discrepancy, you need to call the setter methods to bring wx.DC and wx.GraphicsContext font, pen and brush in sync with each other.
context (wx.GraphicsContext) –
__init__ (self)
GetGraphicsContext
(self)¶Retrieves associated wx.GraphicsContext.
SetGraphicsContext
(self, context)¶Set the graphics context to be used for this wx.GCDC.
Note that this object takes ownership of context and will delete it when it is destroyed or when SetGraphicsContext
is called again.
Also, unlike the constructor taking wx.GraphicsContext, this method will reapply the current font, pen and brush, so that this object continues to use them, if they had been changed before (which is never the case when constructing wx.GCDC directly from wx.GraphicsContext).
context (wx.GraphicsContext) –
GraphicsContext
¶See GetGraphicsContext
and SetGraphicsContext