A wx.DC is a “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 wx.GraphicsContext, wx.GraphicsRenderer and related classes. There is also a wx.GCDC linking the APIs by offering the wx.DC API on top of a wx.GraphicsContext.
wx.DC is an abstract base class and cannot be created directly. Use wx.PaintDC, wx.ClientDC, wx.WindowDC, wx.ScreenDC, wx.MemoryDC or wx.PrinterDC. Notice that device contexts which are associated with windows (i.e. wx.ClientDC, wx.WindowDC and wx.PaintDC) use the window font and colours by default (starting with wxWidgets 2.9.0) but the other device context classes use system-default values so you always must set the appropriate fonts and colours before using them.
In addition to the versions of the methods documented below, there are also versions which accept single wx.Point parameter instead of the two int ones or wx.Point and wx.Size instead of the four int parameters.
Beginning with wxWidgets 2.9.0 the entire wx.DC code has been reorganized. All platform dependent code (actually all drawing code) has been moved into backend classes which derive from a common DCImpl class. The user-visible classes such as wx.ClientDC and wx.PaintDC merely forward all calls to the backend implementation.
In the wx.DC context there is a distinction between logical units and device units. Device units are the units native to the particular device; e.g. for a screen, a device unit is a pixel. For a printer, the device unit is defined by the resolution of the printer (usually given in DPI:
dot-per-inch). All wx.DC functions use instead logical units, unless where explicitly stated. Logical units are arbitrary units mapped to device units using the current mapping mode (see wx.DC.SetMapMode
). This mechanism allows to reuse the same code which prints on e.g. a window on the screen to print on e.g. a paper.
In general wx.DC methods don’t support alpha transparency and the alpha component of wx.Colour is simply ignored and you need to use wx.GraphicsContext for full transparency support. There are, however, a few exceptions: first, under Mac OS X colours with alpha channel are supported in all the normal DC-derived classes as they use wx.GraphicsContext internally. Second, under all platforms wx.SVGFileDC also fully supports alpha channel. In both of these cases the instances of wx.Pen or wx.Brush that are built from wx.Colour use the colour’s alpha values when stroking or filling.
On some platforms (currently only under MSW and only on Windows NT, i.e. not Windows 9x/ME, systems) wx.DC has support for applying an arbitrary affine transformation matrix to its coordinate system. Call CanUseTransformMatrix
to check if this support is available and then call SetTransformMatrix
if it is. If the transformation matrix is not supported, SetTransformMatrix
always simply returns False
and doesn’t do anything.
See also
Device Contexts, wx.GraphicsContext, wx.DCFontChanger, wx.DCTextColourChanger, wx.DCPenChanger, wx.DCBrushChanger, wx.DCClipper
Todo
Precise definition of default/initial state. Pixelwise definition of operations (e.g. last point of a line not drawn).
wx.GCDC, wx.MemoryDC, wx.msw.MetafileDC, wx.MirrorDC, wx.PostScriptDC, wx.PrinterDC, wx.ScreenDC, wx.SVGFileDC, wx.WindowDC
Blit |
Copy from a source DC to this DC. |
CalcBoundingBox |
Adds the specified point to the bounding box which can be retrieved with MinX , MaxX and MinY , MaxY functions. |
CanDrawBitmap |
Does the DC support drawing bitmaps? |
CanGetTextExtent |
Does the DC support calculating the size required to draw text? |
CanUseTransformMatrix |
Check if the use of transformation matrix is supported by the current system. |
Clear |
Clears the device context using the current background brush. |
CopyAttributes |
Copy attributes from another DC. |
CrossHair |
Displays a cross hair using the current pen. |
DestroyClippingRegion |
Destroys the current clipping region so that none of the DC is clipped. |
DeviceToLogicalX |
Convert device X coordinate to logical coordinate, using the current mapping mode, user scale factor, device origin and axis orientation. |
DeviceToLogicalXRel |
Convert device X coordinate to relative logical coordinate, using the current mapping mode and user scale factor but ignoring the axis orientation. |
DeviceToLogicalY |
Converts device Y coordinate to logical coordinate, using the current mapping mode, user scale factor, device origin and axis orientation. |
DeviceToLogicalYRel |
Convert device Y coordinate to relative logical coordinate, using the current mapping mode and user scale factor but ignoring the axis orientation. |
DrawArc |
Draws an arc from the given start to the given end point. |
DrawBitmap |
Draw a bitmap on the device context at the specified point. |
DrawCheckMark |
Draws a check mark inside the given rectangle. |
DrawCircle |
Draws a circle with the given centre and radius. |
DrawEllipse |
Draws an ellipse contained in the rectangle specified either with the given top left corner and the given size or directly. |
DrawEllipseList |
Draw a list of ellipses as quickly as possible. |
DrawEllipticArc |
Draws an arc of an ellipse. |
DrawIcon |
Draw an icon on the display (does nothing if the device context is PostScript). |
DrawLabel |
Draw optional bitmap and the text into the given rectangle and aligns it as specified by alignment parameter; it also will emphasize the character with the given index if it is != -1 and return the bounding rectangle if required. |
DrawLine |
Draws a line from the first point to the second. |
DrawLineList |
Draw a list of lines as quickly as possible. |
DrawLines |
This method uses a list of Points, adding the optional offset coordinate. |
DrawPoint |
Draws a point using the color of the current pen. |
DrawPointList |
Draw a list of points as quickly as possible. |
DrawPolygon |
This method draws a filled polygon using a list of Points, adding the optional offset coordinate. |
DrawPolygonList |
Draw a list of polygons, each of which is a list of points. |
DrawRectangle |
Draws a rectangle with the given top left corner, and with the given size. |
DrawRectangleList |
Draw a list of rectangles as quickly as possible. |
DrawRotatedText |
Draws the text rotated by angle degrees (positive angles are counterclockwise; the full angle is 360 degrees). |
DrawRoundedRectangle |
Draws a rectangle with the given top left corner, and with the given size. |
DrawSpline |
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts. |
DrawText |
Draws a text string at the specified point, using the current text font, and the current text foreground and background colours. |
DrawTextList |
Draw a list of strings using a list of coordinants for positioning each string. |
EndDoc |
Ends a document (only relevant when outputting to a printer). |
EndPage |
Ends a document page (only relevant when outputting to a printer). |
FloodFill |
Flood fills the device context starting from the given point, using the current brush colour, and using a style |
GetAsBitmap |
If supported by the platform and the type of DC, fetch the contents of the DC, or a subset of it, as a bitmap. |
GetBackground |
Gets the brush used for painting the background. |
GetBackgroundMode |
Returns the current background mode: SOLID or TRANSPARENT . |
GetBoundingBox |
GetBoundingBox() . (x1,y1, x2,y2) |
GetBrush |
Gets the current brush. |
GetCGContext |
|
GetCharHeight |
Gets the character height of the currently set font. |
GetCharWidth |
Gets the average character width of the currently set font. |
GetClippingBox |
Gets the rectangle surrounding the current clipping region. |
GetClippingRect |
Gets the rectangle surrounding the current clipping region |
GetDepth |
Returns the depth (number of bits/pixel) of this DC. |
GetDeviceOrigin |
Returns the current device origin. |
GetFont |
Gets the current font. |
GetFontMetrics |
Returns the various font characteristics. |
GetGdkDrawable |
|
GetHDC |
|
GetHandle |
Returns a value that can be used as a handle to the native drawing context, if this wx.DC has something that could be thought of in that way. |
GetLayoutDirection |
Gets the current layout direction of the device context. |
GetLogicalFunction |
Gets the current logical function. |
GetLogicalOrigin |
Return the coordinates of the logical point (0, 0). |
GetLogicalScale |
Return the scale set by the last call to SetLogicalScale . |
GetMapMode |
Gets the current mapping mode for the device context. |
GetFullMultiLineTextExtent |
Gets the dimensions of the string as it would be drawn. |
GetMultiLineTextExtent |
Return the dimensions of the given string’s text extent using the |
GetPPI |
Returns the resolution of the device in pixels per inch. |
GetPartialTextExtents |
Fills the widths array with the widths from the beginning of text to the corresponding character of text. |
GetPen |
Gets the current pen. |
GetPixel |
Gets the colour at the specified location on the DC. |
GetSize |
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts. |
GetSizeMM |
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts. |
GetTextBackground |
Gets the current text background colour. |
GetFullTextExtent |
Gets the dimensions of the string as it would be drawn. |
GetTextExtent |
Return the dimensions of the given string’s text extent using the |
GetTextForeground |
Gets the current text foreground colour. |
GetTransformMatrix |
Return the transformation matrix used by this device context. |
GetUserScale |
Gets the current user scale factor. |
GradientFillConcentric |
Fill the area specified by rect with a radial gradient, starting from initialColour at the centre of the circle and fading to destColour on the circle outside. |
GradientFillLinear |
Fill the area specified by rect with a linear gradient, starting from initialColour and eventually fading to destColour. |
IsOk |
Returns True if the DC is ok to use. |
LogicalToDeviceX |
Converts logical X coordinate to device coordinate, using the current mapping mode, user scale factor, device origin and axis orientation. |
LogicalToDeviceXRel |
Converts logical X coordinate to relative device coordinate, using the current mapping mode and user scale factor but ignoring the axis orientation. |
LogicalToDeviceY |
Converts logical Y coordinate to device coordinate, using the current mapping mode, user scale factor, device origin and axis orientation. |
LogicalToDeviceYRel |
Converts logical Y coordinate to relative device coordinate, using the current mapping mode and user scale factor but ignoring the axis orientation. |
MaxX |
Gets the maximum horizontal extent used in drawing commands so far. |
MaxY |
Gets the maximum vertical extent used in drawing commands so far. |
MinX |
Gets the minimum horizontal extent used in drawing commands so far. |
MinY |
Gets the minimum vertical extent used in drawing commands so far. |
ResetBoundingBox |
Resets the bounding box: after a call to this function, the bounding box doesn’t contain anything. |
ResetTransformMatrix |
Revert the transformation matrix to identity matrix. |
SetAxisOrientation |
Sets the x and y axis orientation (i.e. the direction from lowest to highest values on the axis). |
SetBackground |
Sets the current background brush for the DC. |
SetBackgroundMode |
mode may be one of SOLID and TRANSPARENT . |
SetBrush |
Sets the current brush for the DC. |
SetClippingRegion |
Sets the clipping region for this device context to the intersection of the given region described by the parameters of this method and the previously set clipping region. |
SetDeviceClippingRegion |
Sets the clipping region for this device context. |
SetDeviceOrigin |
Sets the device origin (i.e. the origin in pixels after scaling has been applied). |
SetFont |
Sets the current font for the DC. |
SetLayoutDirection |
Sets the current layout direction for the device context. |
SetLogicalFunction |
Sets the current logical function for the device context. |
SetLogicalOrigin |
Change the offset used for translating wx.DC coordinates. |
SetLogicalScale |
Set the scale to use for translating wx.DC coordinates to the physical pixels. |
SetMapMode |
The mapping mode of the device context defines the unit of measurement used to convert logical units to device units. |
SetPalette |
If this is a window DC or memory DC, assigns the given palette to the window or bitmap associated with the DC. |
SetPen |
Sets the current pen for the DC. |
SetTextBackground |
Sets the current text background colour for the DC. |
SetTextForeground |
Sets the current text foreground colour for the DC. |
SetTransformMatrix |
Set the transformation matrix. |
SetUserScale |
Sets the user scaling factor, useful for applications which require ‘zooming’. |
StartDoc |
Starts a document (only relevant when outputting to a printer). |
StartPage |
Starts a document page (only relevant when outputting to a printer). |
StretchBlit |
Copy from a source DC to this DC possibly changing the scale. |
_DrawEllipseList |
|
_DrawLineList |
|
_DrawPointList |
|
_DrawPolygonList |
|
_DrawRectangleList |
|
_DrawTextList |
|
__nonzero__ |
wx.
DC
(Object)¶A DC is a “device context” onto which graphics and text can be drawn.
Blit
(self, xdest, ydest, width, height, source, xsrc, ysrc, logicalFunc=COPY, useMask=False, xsrcMask=DefaultCoord, ysrcMask=DefaultCoord)¶Copy from a source DC to this DC.
With this method you can specify the destination coordinates and the size of area to copy which will be the same for both the source and target DCs. If you need to apply scaling while copying, use StretchBlit
.
Notice that source DC coordinates xsrc and ysrc are interpreted using the current source DC coordinate system, i.e. the scale, origin position and axis directions are taken into account when transforming them to physical (pixel) coordinates.
Parameters: |
|
---|---|
Return type: | bool |
Note
There is partial support for Blit
in wx.PostScriptDC, under X.
See also
CalcBoundingBox
(self, x, y)¶Adds the specified point to the bounding box which can be retrieved with MinX
, MaxX
and MinY
, MaxY
functions.
Parameters: |
|
---|
See also
CanDrawBitmap
(self)¶Does the DC support drawing bitmaps?
Return type: | bool |
---|
CanGetTextExtent
(self)¶Does the DC support calculating the size required to draw text?
Return type: | bool |
---|
CanUseTransformMatrix
(self)¶Check if the use of transformation matrix is supported by the current system.
Currently this function always returns False
for non-MSW platforms and may return False
for old (Windows 9x/ME) Windows systems. Normally support for the transformation matrix is always available in any relatively recent Windows versions.
Return type: | bool |
---|
New in version 2.9.2.
Clear
(self)¶Clears the device context using the current background brush.
CopyAttributes
(self, dc)¶Copy attributes from another DC.
The copied attributes currently are:
Parameters: | dc (wx.DC) – A valid (i.e. its IsOk must return True ) source device context. |
---|
CrossHair
(self, *args, **kw)¶CrossHair (self, x, y)
Displays a cross hair using the current pen.
This is a vertical and horizontal line the height and width of the window, centred on the given point.
Parameters: |
|
---|
CrossHair (self, pt)
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
Parameters: | pt (wx.Point) – |
---|
DestroyClippingRegion
(self)¶Destroys the current clipping region so that none of the DC is clipped.
See also
DeviceToLogicalX
(self, x)¶Convert device X coordinate to logical coordinate, using the current mapping mode, user scale factor, device origin and axis orientation.
Parameters: | x (int) – |
---|---|
Return type: | wx.Coord |
DeviceToLogicalXRel
(self, x)¶Convert device X coordinate to relative logical coordinate, using the current mapping mode and user scale factor but ignoring the axis orientation.
Use this for converting a width, for example.
Parameters: | x (int) – |
---|---|
Return type: | wx.Coord |
DeviceToLogicalY
(self, y)¶Converts device Y coordinate to logical coordinate, using the current mapping mode, user scale factor, device origin and axis orientation.
Parameters: | y (int) – |
---|---|
Return type: | wx.Coord |
DeviceToLogicalYRel
(self, y)¶Convert device Y coordinate to relative logical coordinate, using the current mapping mode and user scale factor but ignoring the axis orientation.
Use this for converting a height, for example.
Parameters: | y (int) – |
---|---|
Return type: | wx.Coord |
DrawArc
(self, *args, **kw)¶DrawArc (self, xStart, yStart, xEnd, yEnd, xc, yc)
Draws an arc from the given start to the given end point.
The arc drawn is an arc of the circle centered at ( xc, yc). Its start point is (xStart, yStart) whereas its end point is the point of intersection of the line passing by (xc, yc) and (xEnd, yEnd) with the circle passing by (xStart, yStart).
The arc is drawn in a counter-clockwise direction between the start and the end points.
The current pen is used for the outline and the current brush for filling the shape. Notice that unless the brush is transparent, the lines connecting the centre of the circle to the end points of the arc are drawn as well.
Parameters: |
|
---|
Note
DrawEllipticArc
has more clear semantics and it is recommended to use it instead of this function.
DrawArc (self, ptStart, ptEnd, centre)
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
Parameters: |
---|
DrawBitmap
(self, *args, **kw)¶DrawBitmap (self, bitmap, x, y, useMask=False)
Draw a bitmap on the device context at the specified point.
If transparent is True
and the bitmap has a transparency mask, the bitmap will be drawn transparently.
When drawing a mono-bitmap, the current text foreground colour will be used to draw the foreground of the bitmap (all bits set to 1), and the current text background colour to draw the background (all bits set to 0).
Parameters: |
|
---|
See also
DrawBitmap (self, bmp, pt, useMask=False)
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
Parameters: |
---|
DrawCheckMark
(self, *args, **kw)¶DrawCheckMark (self, x, y, width, height)
Draws a check mark inside the given rectangle.
Parameters: |
|
---|
DrawCheckMark (self, rect)
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
Parameters: | rect (wx.Rect) – |
---|
DrawCircle
(self, *args, **kw)¶DrawCircle (self, x, y, radius)
Draws a circle with the given centre and radius.
Parameters: |
|
---|
See also
DrawCircle (self, pt, radius)
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
Parameters: |
|
---|
DrawEllipse
(self, *args, **kw)¶DrawEllipse (self, x, y, width, height)
Draws an ellipse contained in the rectangle specified either with the given top left corner and the given size or directly.
The current pen is used for the outline and the current brush for filling the shape.
Parameters: |
|
---|
See also
DrawEllipse (self, pt, size)
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
Parameters: |
---|
DrawEllipse (self, rect)
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
Parameters: | rect (wx.Rect) – |
---|
DrawEllipseList
(self, ellipses, pens=None, brushes=None)¶Draw a list of ellipses as quickly as possible.
Parameters: |
|
---|
DrawEllipticArc
(self, *args, **kw)¶DrawEllipticArc (self, x, y, width, height, start, end)
Draws an arc of an ellipse.
The current pen is used for drawing the arc and the current brush is used for drawing the pie.
x and y specify the x and y coordinates of the upper-left corner of the rectangle that contains the ellipse.
width and height specify the width and height of the rectangle that contains the ellipse.
start and end specify the start and end of the arc relative to the three-o’clock position from the center of the rectangle. Angles are specified in degrees with 0 degree angle corresponding to the positive horizontal axis (3 o’clock) direction. Positive values mean counter-clockwise motion. If start is equal to end, a complete ellipse will be drawn.
Notice that unlike DrawArc
, this function does not draw the lines to the arc ends, even when using non-transparent brush.
Parameters: |
|
---|
DrawEllipticArc (self, pt, sz, sa, ea)
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
Parameters: |
---|
DrawIcon
(self, *args, **kw)¶DrawIcon (self, icon, x, y)
Draw an icon on the display (does nothing if the device context is PostScript).
This can be the simplest way of drawing bitmaps on a window.
Parameters: |
|
---|
DrawIcon (self, icon, pt)
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
Parameters: |
---|
DrawLabel
(self, *args, **kw)¶DrawLabel (self, text, bitmap, rect, alignment=ALIGN_LEFT|ALIGN_TOP, indexAccel=-1)
Draw optional bitmap and the text into the given rectangle and aligns it as specified by alignment parameter; it also will emphasize the character with the given index if it is != -1 and return the bounding rectangle if required.
Parameters: | |
---|---|
Return type: |
DrawLabel (self, text, rect, alignment=ALIGN_LEFT|ALIGN_TOP, indexAccel=-1)
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
Parameters: |
|
---|
DrawLine
(self, *args, **kw)¶DrawLine (self, x1, y1, x2, y2)
Draws a line from the first point to the second.
The current pen is used for drawing the line. Note that the point (x2, y2) is not part of the line and is not drawn by this function (this is consistent with the behaviour of many other toolkits).
Parameters: |
|
---|
DrawLine (self, pt1, pt2)
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
Parameters: |
---|
DrawLineList
(self, lines, pens=None)¶Draw a list of lines as quickly as possible.
Parameters: |
|
---|
DrawLines
(self, points, xoffset=0, yoffset=0)¶This method uses a list of Points, adding the optional offset coordinate.
The programmer is responsible for deleting the list of points.
DrawPoint
(self, *args, **kw)¶DrawPoint (self, x, y)
Draws a point using the color of the current pen.
Note that the other properties of the pen are not used, such as width.
Parameters: |
|
---|
DrawPoint (self, pt)
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
Parameters: | pt (wx.Point) – |
---|
DrawPointList
(self, points, pens=None)¶Draw a list of points as quickly as possible.
Parameters: |
|
---|
DrawPolygon
(self, points, xoffset=0, yoffset=0, fill_style=ODDEVEN_RULE)¶This method draws a filled polygon using a list of Points, adding the optional offset coordinate.
The first and last points are automatically closed.
The last argument specifies the fill rule: wx.ODDEVEN_RULE
(the default) or wx.WINDING_RULE
.
The current pen is used for drawing the outline, and the current brush for filling the shape. Using a transparent brush suppresses filling.
The programmer is responsible for deleting the list of points.
DrawPolygonList
(self, polygons, pens=None, brushes=None)¶Draw a list of polygons, each of which is a list of points.
Parameters: |
|
---|
DrawRectangle
(self, *args, **kw)¶DrawRectangle (self, x, y, width, height)
Draws a rectangle with the given top left corner, and with the given size.
The current pen is used for the outline and the current brush for filling the shape.
Parameters: |
|
---|
DrawRectangle (self, pt, sz)
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
Parameters: |
---|
DrawRectangle (self, rect)
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
Parameters: | rect (wx.Rect) – |
---|
DrawRectangleList
(self, rectangles, pens=None, brushes=None)¶Draw a list of rectangles as quickly as possible.
Parameters: |
|
---|
DrawRotatedText
(self, *args, **kw)¶DrawRotatedText (self, text, x, y, angle)
Draws the text rotated by angle degrees (positive angles are counterclockwise; the full angle is 360 degrees).
Parameters: |
|
---|
Note
Under Win9x only TrueType fonts can be drawn by this function. In particular, a font different from NORMAL_FONT
should be used as the latter is not a TrueType font. SWISS_FONT
is an example of a font which is.
See also
DrawRotatedText (self, text, point, angle)
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
Parameters: |
|
---|
DrawRoundedRectangle
(self, *args, **kw)¶DrawRoundedRectangle (self, x, y, width, height, radius)
Draws a rectangle with the given top left corner, and with the given size.
The corners are quarter-circles using the given radius. The current pen is used for the outline and the current brush for filling the shape.
If radius is positive, the value is assumed to be the radius of the rounded corner. If radius is negative, the absolute value is assumed to be the proportion of the smallest dimension of the rectangle. This means that the corner can be a sensible size relative to the size of the rectangle, and also avoids the strange effects X produces when the corners are too big for the rectangle.
Parameters: |
|
---|
DrawRoundedRectangle (self, pt, sz, radius)
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
Parameters: |
---|
DrawRoundedRectangle (self, rect, radius)
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
Parameters: |
|
---|
DrawSpline
(self, *args, **kw)¶DrawSpline (self, points)
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
DrawSpline (self, x1, y1, x2, y2, x3, y3)
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
DrawText
(self, *args, **kw)¶DrawText (self, text, x, y)
Draws a text string at the specified point, using the current text font, and the current text foreground and background colours.
The coordinates refer to the top-left corner of the rectangle bounding the string. See GetTextExtent
for how to get the dimensions of a text string, which can be used to position the text more precisely and DrawLabel
if you need to align the string differently.
Starting from wxWidgets 2.9.2 text parameter can be a multi-line string, i.e. contain new line characters, and will be rendered correctly.
Parameters: |
|
---|
Note
The current logical function is ignored by this function.
DrawText (self, text, pt)
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
Parameters: |
|
---|
DrawTextList
(self, textList, coords, foregrounds=None, backgrounds=None)¶Draw a list of strings using a list of coordinants for positioning each string.
Parameters: |
---|
NOTE
: Make sure you set background mode to wx.Solid (DC.SetBackgroundMode)EndDoc
(self)¶Ends a document (only relevant when outputting to a printer).
EndPage
(self)¶Ends a document page (only relevant when outputting to a printer).
FloodFill
(self, *args, **kw)¶FloodFill (self, x, y, colour, style=FLOOD_SURFACE)
Flood fills the device context starting from the given point, using the current brush colour, and using a style:
wx.FLOOD_SURFACE
: The flooding occurs until a colour other than the given colour is encountered.wx.FLOOD_BORDER
: The area to be flooded is bounded by the given colour.Currently this method is not implemented in wxOSX and does nothing there.
Parameters: |
|
---|---|
Return type: | bool |
Returns: |
|
Note
The present implementation for non-Windows platforms may fail to find colour borders if the pixels do not match the colour exactly. However the function will still return True
.
Note
This method shouldn’t be used with wx.PaintDC under non-Windows platforms as it uses GetPixel
internally and this may give wrong results, notably in wxGTK. If you need to flood fill wx.PaintDC, create a temporary wx.MemoryDC, flood fill it and then blit it to, or draw as a bitmap on, wx.PaintDC. See the example of doing this in the drawing sample and wx.BufferedPaintDC class.
FloodFill (self, pt, col, style=FLOOD_SURFACE)
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
Parameters: |
|
---|---|
Return type: | bool |
GetAsBitmap
(self, subrect=None)¶If supported by the platform and the type of DC, fetch the contents of the DC, or a subset of it, as a bitmap.
Parameters: | subrect (wx.Rect) – |
---|---|
Return type: | wx.Bitmap |
GetBackground
(self)¶Gets the brush used for painting the background.
Return type: | wx.Brush |
---|
See also
GetBackgroundMode
(self)¶Returns the current background mode: SOLID
or TRANSPARENT
.
Return type: | int |
---|
See also
GetBoundingBox
(self)¶Returns the min and max points used in drawing commands so far.
GetCGContext
(self)¶Return type: | wx.UIntPtr |
---|
GetCharHeight
(self)¶Gets the character height of the currently set font.
Return type: | wx.Coord |
---|
GetCharWidth
(self)¶Gets the average character width of the currently set font.
Return type: | wx.Coord |
---|
GetClippingBox
(self)¶Gets the rectangle surrounding the current clipping region.
Return type: | tuple |
---|---|
Returns: | ( x, y, width, height ) |
GetClippingRect
(self)¶Gets the rectangle surrounding the current clipping region
GetDepth
(self)¶Returns the depth (number of bits/pixel) of this DC.
Return type: | int |
---|
See also
GetFont
(self)¶Gets the current font.
Notice that even although each device context object has some default font after creation, this method would return a wx.NullFont
initially and only after calling SetFont
a valid font is returned.
Return type: | wx.Font |
---|
GetFontMetrics
(self)¶Returns the various font characteristics.
This method allows to retrieve some of the font characteristics not returned by GetTextExtent
, notably internal leading and average character width.
Currently this method returns correct results only under wxMSW, in the other ports the internal leading will always be 0 and the average character width will be computed as the width of the character ‘x’.
Return type: | wx.FontMetrics |
---|
New in version 2.9.2.
GetGdkDrawable
(self)¶Return type: | wx.UIntPtr |
---|
GetHDC
(self)¶Return type: | long |
---|
GetHandle
(self)¶Returns a value that can be used as a handle to the native drawing context, if this wx.DC has something that could be thought of in that way.
(Not all of them do.)
For example, on Windows the return value is an HDC
, on OSX it is a CGContextRef and on wxGTK it will be a GdkDrawable. If the DC is a wx.GCDC then the return value will be the value returned from wx.GraphicsContext.GetNativeContext
. A value of None
is returned if the DC does not have anything that fits the handle concept.
Return type: | wx.UIntPtr |
---|
New in version 2.9.5.
GetLayoutDirection
(self)¶Gets the current layout direction of the device context.
On platforms where RTL layout is supported, the return value will either be Layout_LeftToRight
or Layout_RightToLeft
. If RTL layout is not supported, the return value will be Layout_Default
.
Return type: | wx.LayoutDirection |
---|
See also
GetLogicalFunction
(self)¶Gets the current logical function.
Return type: | wx.RasterOperationMode |
---|
See also
GetLogicalOrigin
(self)¶Return the coordinates of the logical point (0, 0).
Return type: | tuple |
---|---|
Returns: | ( x, y ) |
See also
GetLogicalScale
(self)¶Return the scale set by the last call to SetLogicalScale
.
Return type: | tuple |
---|---|
Returns: | ( x, y ) |
GetMapMode
(self)¶Gets the current mapping mode for the device context.
Return type: | wx.MappingMode |
---|
See also
GetFullMultiLineTextExtent
(self, string, font=None)¶Gets the dimensions of the string as it would be drawn.
The string
parameter is the string to measure. The return value
is a tuple of integer values consisting of widget
, height
and
heightLine
. The heightLine
is the the height of a single line.
If the optional parameter font
is specified and valid, then it is
used for the text extent calculation. Otherwise the currently selected
font is.
Note
This function works with both single-line and multi-line strings.
Parameters: |
|
---|---|
Return type: | tuple |
Returns: | ( w, h, heightLine ) |
GetMultiLineTextExtent
(self, st)¶Return the dimensions of the given string’s text extent using the currently selected font, taking into account multiple lines if present in the string.
Parameters: | st – The string to be measured |
---|
See also
Return type: | wx.Size |
---|
GetPartialTextExtents
(self, text)¶Fills the widths array with the widths from the beginning of text to the corresponding character of text.
The generic version simply builds a running total of the widths of each character using GetTextExtent
, however if the various platforms have a native API function that is faster or more accurate than the generic implementation then it should be used instead.
GetSize
(self)¶This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
Return type: | wx.Size |
---|
GetSizeMM
(self)¶This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
Return type: | wx.Size |
---|
GetFullTextExtent
(self, string, font=None)¶Gets the dimensions of the string as it would be drawn.
The string
parameter is the string to measure. The return value
is a tuple of integer values consisting of widget
, height
,
decent
and externalLeading
. The descent
is the dimension
from the baseline of the font to the bottom of the descender, and
externalLeading
is any extra vertical space added to the font by the
font designer (usually is zero).
If the optional parameter font
is specified and valid, then it is
used for the text extent calculation. Otherwise the currently selected
font is.
Parameters: |
|
---|---|
Return type: | tuple |
Returns: | ( w, h, descent, externalLeading ) |
GetTextExtent
(self, st)¶Return the dimensions of the given string’s text extent using the currently selected font.
Parameters: | st – The string to be measured |
---|
See also
Return type: | wx.Size |
---|
GetTransformMatrix
(self)¶Return the transformation matrix used by this device context.
By default the transformation matrix is the identity matrix.
Return type: | wx.AffineMatrix2D |
---|
New in version 2.9.2.
GetUserScale
(self)¶Gets the current user scale factor.
GradientFillConcentric
(self, *args, **kw)¶GradientFillConcentric (self, rect, initialColour, destColour)
Fill the area specified by rect with a radial gradient, starting from initialColour at the centre of the circle and fading to destColour on the circle outside.
The circle is placed at the centre of rect.
Parameters: |
---|
Note
Currently this function is very slow, don’t use it for real-time drawing.
GradientFillConcentric (self, rect, initialColour, destColour, circleCenter)
Fill the area specified by rect with a radial gradient, starting from initialColour at the centre of the circle and fading to destColour on the circle outside.
circleCenter are the relative coordinates of centre of the circle in the specified rect.
Parameters: |
---|
Note
Currently this function is very slow, don’t use it for real-time drawing.
GradientFillLinear
(self, rect, initialColour, destColour, nDirection=RIGHT)¶Fill the area specified by rect with a linear gradient, starting from initialColour and eventually fading to destColour.
The nDirection specifies the direction of the colour change, default is to use initialColour on the left part of the rectangle and destColour on the right one.
Parameters: |
---|
IsOk
(self)¶Returns True
if the DC is ok to use.
Return type: | bool |
---|
LogicalToDeviceX
(self, x)¶Converts logical X coordinate to device coordinate, using the current mapping mode, user scale factor, device origin and axis orientation.
Parameters: | x (int) – |
---|---|
Return type: | wx.Coord |
LogicalToDeviceXRel
(self, x)¶Converts logical X coordinate to relative device coordinate, using the current mapping mode and user scale factor but ignoring the axis orientation.
Use this for converting a width, for example.
Parameters: | x (int) – |
---|---|
Return type: | wx.Coord |
LogicalToDeviceY
(self, y)¶Converts logical Y coordinate to device coordinate, using the current mapping mode, user scale factor, device origin and axis orientation.
Parameters: | y (int) – |
---|---|
Return type: | wx.Coord |
LogicalToDeviceYRel
(self, y)¶Converts logical Y coordinate to relative device coordinate, using the current mapping mode and user scale factor but ignoring the axis orientation.
Use this for converting a height, for example.
Parameters: | y (int) – |
---|---|
Return type: | wx.Coord |
MaxX
(self)¶Gets the maximum horizontal extent used in drawing commands so far.
Return type: | wx.Coord |
---|
MaxY
(self)¶Gets the maximum vertical extent used in drawing commands so far.
Return type: | wx.Coord |
---|
MinX
(self)¶Gets the minimum horizontal extent used in drawing commands so far.
Return type: | wx.Coord |
---|
MinY
(self)¶Gets the minimum vertical extent used in drawing commands so far.
Return type: | wx.Coord |
---|
ResetBoundingBox
(self)¶Resets the bounding box: after a call to this function, the bounding box doesn’t contain anything.
See also
ResetTransformMatrix
(self)¶Revert the transformation matrix to identity matrix.
New in version 2.9.2.
SetAxisOrientation
(self, xLeftRight, yBottomUp)¶Sets the x and y axis orientation (i.e. the direction from lowest to highest values on the axis).
The default orientation is x axis from left to right and y axis from top down.
Parameters: |
|
---|
SetBackground
(self, brush)¶Sets the current background brush for the DC.
Parameters: | brush (wx.Brush) – |
---|
SetBackgroundMode
(self, mode)¶mode may be one of SOLID
and TRANSPARENT
.
This setting determines whether text will be drawn with a background colour or not.
Parameters: | mode (int) – |
---|
SetBrush
(self, brush)¶Sets the current brush for the DC.
If the argument is wx.NullBrush
(or another invalid brush; see wx.Brush.IsOk
), the current brush is selected out of the device context (leaving wx.DC without any valid brush), allowing the current brush to be destroyed safely.
Parameters: | brush (wx.Brush) – |
---|
See also
wx.Brush, wx.MemoryDC (for the interpretation of colours when drawing into a monochrome bitmap)
SetClippingRegion
(self, *args, **kw)¶SetClippingRegion (self, x, y, width, height)
Sets the clipping region for this device context to the intersection of the given region described by the parameters of this method and the previously set clipping region.
The clipping region is an area to which drawing is restricted. Possible uses for the clipping region are for clipping text or for speeding up window redraws when only a known area of the screen is damaged.
Notice that you need to call DestroyClippingRegion
if you want to set the clipping region exactly to the region specified.
Also note that if the clipping region is empty, any previously set clipping region is destroyed, i.e. it is equivalent to calling DestroyClippingRegion
, and not to clipping out all drawing on the DC as might be expected.
Parameters: |
|
---|
See also
SetClippingRegion (self, pt, sz)
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
Parameters: |
---|
SetClippingRegion (self, rect)
This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
Parameters: | rect (wx.Rect) – |
---|
SetDeviceClippingRegion
(self, region)¶Sets the clipping region for this device context.
Unlike SetClippingRegion
, this function works with physical coordinates and not with the logical ones.
Parameters: | region (wx.Region) – |
---|
SetDeviceOrigin
(self, x, y)¶Sets the device origin (i.e. the origin in pixels after scaling has been applied).
This function may be useful in Windows printing operations for placing a graphic on a page.
Parameters: |
|
---|
SetFont
(self, font)¶Sets the current font for the DC.
If the argument is wx.NullFont
(or another invalid font; see wx.Font.IsOk
), the current font is selected out of the device context (leaving wx.DC without any valid font), allowing the current font to be destroyed safely.
Parameters: | font (wx.Font) – |
---|
See also
SetLayoutDirection
(self, dir)¶Sets the current layout direction for the device context.
Parameters: | dir (LayoutDirection) – May be either Layout_Default , Layout_LeftToRight or Layout_RightToLeft . |
---|
See also
SetLogicalFunction
(self, function)¶Sets the current logical function for the device context.
It determines how a source pixel (from a pen or brush colour, or source device context if using Blit
) combines with a destination pixel in the current device context. Text drawing is not affected by this function.
See wx.RasterOperationMode enumeration values for more info.
The default is COPY
, which simply draws with the current colour. The others combine the current colour and the background using a logical operation. INVERT
is commonly used for drawing rubber bands or moving outlines, since drawing twice reverts to the original colour.
Parameters: | function (RasterOperationMode) – |
---|
SetLogicalOrigin
(self, x, y)¶Change the offset used for translating wx.DC coordinates.
Parameters: |
|
---|
See also
SetLogicalScale
(self, x, y)¶Set the scale to use for translating wx.DC coordinates to the physical pixels.
The effect of calling this function is similar to that of calling SetUserScale
.
Parameters: |
|
---|
SetMapMode
(self, mode)¶The mapping mode of the device context defines the unit of measurement used to convert logical units to device units.
Note that in X, text drawing isn’t handled consistently with the mapping mode; a font is always specified in point size. However, setting the user scale (see SetUserScale
) scales the text appropriately. In Windows, scalable TrueType fonts are always used; in X, results depend on availability of fonts, but usually a reasonable match is found.
The coordinate origin is always at the top left of the screen/printer.
Drawing to a Windows printer device context uses the current mapping mode, but mapping mode is currently ignored for PostScript output.
Parameters: | mode (MappingMode) – |
---|
SetPalette
(self, palette)¶If this is a window DC or memory DC, assigns the given palette to the window or bitmap associated with the DC.
If the argument is wx.NullPalette
, the current palette is selected out of the device context, and the original palette restored.
Parameters: | palette (wx.Palette) – |
---|
See also
SetPen
(self, pen)¶Sets the current pen for the DC.
If the argument is wx.NullPen
(or another invalid pen; see wx.Pen.IsOk
), the current pen is selected out of the device context (leaving wx.DC without any valid pen), allowing the current pen to be destroyed safely.
Parameters: | pen (wx.Pen) – |
---|
See also
wx.MemoryDC for the interpretation of colours when drawing into a monochrome bitmap.
SetTextBackground
(self, colour)¶Sets the current text background colour for the DC.
Parameters: | colour (wx.Colour) – |
---|
SetTextForeground
(self, colour)¶Sets the current text foreground colour for the DC.
Parameters: | colour (wx.Colour) – |
---|
See also
wx.MemoryDC for the interpretation of colours when drawing into a monochrome bitmap.
SetTransformMatrix
(self, matrix)¶Set the transformation matrix.
If transformation matrix is supported on the current system, the specified matrix will be used to transform between wx.DC and physical coordinates. Otherwise the function returns False
and doesn’t change the coordinate mapping.
Parameters: | matrix (wx.AffineMatrix2D) – |
---|---|
Return type: | bool |
New in version 2.9.2.
SetUserScale
(self, xScale, yScale)¶Sets the user scaling factor, useful for applications which require ‘zooming’.
Parameters: |
|
---|
StartDoc
(self, message)¶Starts a document (only relevant when outputting to a printer).
message is a message to show while printing.
Parameters: | message (string) – |
---|---|
Return type: | bool |
StartPage
(self)¶Starts a document page (only relevant when outputting to a printer).
StretchBlit
(self, xdest, ydest, dstWidth, dstHeight, source, xsrc, ysrc, srcWidth, srcHeight, logicalFunc=COPY, useMask=False, xsrcMask=DefaultCoord, ysrcMask=DefaultCoord)¶Copy from a source DC to this DC possibly changing the scale.
Unlike Blit
, this method allows to specify different source and destination region sizes, meaning that it can stretch or shrink it while copying. The same can be achieved by changing the scale of the source or target DC but calling this method is simpler and can also be more efficient if the platform provides a native implementation of it.
The meaning of its other parameters is the same as with Blit
, in particular all source coordinates are interpreted using the source DC coordinate system, i.e. are affected by its scale, origin translation and axis direction.
Parameters: |
|
---|---|
Return type: | bool |
Blit
in wx.PostScriptDC, under X.
See wx.MemoryDC for typical usage.
New in version 2.9.0.
See also
_DrawEllipseList
(self, pyCoords, pyPens, pyBrushes)¶Return type: | PyObject |
---|
_DrawLineList
(self, pyCoords, pyPens, pyBrushes)¶Return type: | PyObject |
---|
_DrawPointList
(self, pyCoords, pyPens, pyBrushes)¶Return type: | PyObject |
---|
_DrawPolygonList
(self, pyCoords, pyPens, pyBrushes)¶Return type: | PyObject |
---|
_DrawRectangleList
(self, pyCoords, pyPens, pyBrushes)¶Return type: | PyObject |
---|
_DrawTextList
(self, textList, pyPoints, foregroundList, backgroundList)¶Return type: | PyObject |
---|
__nonzero__
(self)¶Return type: | int |
---|
AsBitmap
¶See GetAsBitmap
Background
¶See GetBackground
and SetBackground
BackgroundMode
¶See GetBackgroundMode
and SetBackgroundMode
BoundingBox
¶See GetBoundingBox
CGContext
¶See GetCGContext
CharHeight
¶See GetCharHeight
CharWidth
¶See GetCharWidth
ClippingRect
¶See GetClippingRect
DeviceOrigin
¶See GetDeviceOrigin
and SetDeviceOrigin
FontMetrics
¶See GetFontMetrics
GdkDrawable
¶See GetGdkDrawable
LayoutDirection
¶See GetLayoutDirection
and SetLayoutDirection
LogicalFunction
¶See GetLogicalFunction
and SetLogicalFunction
MapMode
¶See GetMapMode
and SetMapMode
MultiLineTextExtent
¶TextBackground
¶See GetTextBackground
and SetTextBackground
TextExtent
¶See GetTextExtent
TextForeground
¶See GetTextForeground
and SetTextForeground
TransformMatrix
¶See GetTransformMatrix
and SetTransformMatrix