wx.GraphicsContext¶

A wx.GraphicsContext instance is the object that is drawn upon.

It is created by a renderer using wx.GraphicsRenderer.CreateContext . This can be either directly using a renderer instance, or indirectly using the static convenience Create functions of wx.GraphicsContext that always delegate the task to the default renderer.

def OnPaint(self, event):

    # Create paint DC
    dc = wx.PaintDC(self)

    # Create graphics context from it
    gc = wx.GraphicsContext.Create(dc)

    if gc:

        # make a path that contains a circle and some lines
        gc.SetPen(wx.RED_PEN)
        path = gc.CreatePath()
        path.AddCircle(50.0, 50.0, 50.0)
        path.MoveToPoint(0.0, 50.0)
        path.AddLineToPoint(100.0, 50.0)
        path.MoveToPoint(50.0, 0.0)
        path.AddLineToPoint(50.0, 100.0)
        path.CloseSubpath()
        path.AddRectangle(25.0, 25.0, 50.0, 50.0)

        gc.StrokePath(path)

Class Hierarchy¶

Inheritance diagram for class GraphicsContext:

Methods Summary¶

`BeginLayer`	Redirects all rendering is done into a fully transparent temporary context.
`Clip`	Clips drawings to the specified region.
`ConcatTransform`	Concatenates the passed in transform with the current transform of this context.
`Create`	Creates a wx.GraphicsContext from a wx.Window.
`CreateBitmap`	Creates wx.GraphicsBitmap from an existing wx.Bitmap.
`CreateBitmapFromImage`	Creates wx.GraphicsBitmap from an existing wx.Image.
`CreateBrush`	Creates a native brush from a wx.Brush.
`CreateFont`	Creates a native graphics font from a wx.Font and a text colour.
`CreateFromNative`	Creates a wx.GraphicsContext from a native context.
`CreateFromNativeWindow`	Creates a wx.GraphicsContext from a native window.
`CreateLinearGradientBrush`	Creates a native brush with a linear gradient.
`CreateMatrix`	Creates a native affine transformation matrix from the passed in values.
`CreatePath`	Creates a native graphics path which is initially empty.
`CreatePen`	Creates a native pen from a wx.Pen.
`CreateRadialGradientBrush`	Creates a native brush with a radial gradient.
`CreateSubBitmap`	Extracts a sub-bitmap from an existing bitmap.
`DisableOffset`
`DrawBitmap`	Draws the bitmap.
`DrawEllipse`	Draws an ellipse.
`DrawIcon`	Draws the icon.
`DrawLines`	Draws a polygon.
`DrawPath`	Draws the path by first filling and then stroking.
`DrawRectangle`	Draws a rectangle.
`DrawRoundedRectangle`	Draws a rounded rectangle.
`DrawText`	Draws text at the defined position.
`EnableOffset`
`EndDoc`	Done with that document (relevant only for printing / pdf etc.)
`EndLayer`	Composites back the drawings into the context with the opacity given at the BeginLayer call.
`EndPage`	Ends the current page (relevant only for printing / pdf etc.)
`FillPath`	Fills the path with the current brush.
`Flush`	Make sure that the current content of this context is immediately visible.
`GetAntialiasMode`	Returns the current shape antialiasing mode.
`GetCompositionMode`	Returns the current compositing operator.
`GetDPI`	Returns the resolution of the graphics context in device points per inch.
`GetInterpolationQuality`	Returns the current interpolation quality.
`GetNativeContext`	Returns the native context (CGContextRef for Core Graphics, Graphics pointer for GDIPlus and cairo_t pointer for cairo).
`GetPartialTextExtents`	Fills the widths array with the widths from the beginning of text to the corresponding character of text.
`GetSize`	Returns the size of the graphics context in device coordinates.
`GetFullTextExtent`	Gets the dimensions of the string using the currently selected font.
`GetTransform`	Gets the current transformation matrix of this context.
`OffsetEnabled`
`PopState`	Pops a stored state from the stack and sets the current transformation matrix to that state.
`PushState`	Push the current state of the context’s transformation matrix on a stack.
`ResetClip`	Resets the clipping to original shape.
`Rotate`	Rotates the current transformation matrix (in radians).
`Scale`	Scales the current transformation matrix.
`SetAntialiasMode`	Sets the antialiasing mode, returns `True` if it supported.
`SetBrush`	Sets the brush for filling paths.
`SetCompositionMode`	Sets the compositing operator, returns `True` if it supported.
`SetFont`	Sets the font for drawing text.
`SetInterpolationQuality`	Sets the interpolation quality, returns `True` if it is supported.
`SetPen`	Sets the pen used for stroking.
`SetTransform`	Sets the current transformation matrix of this context.
`ShouldOffset`
`StartDoc`	Begin a new document (relevant only for printing / pdf etc.) If there is a progress dialog, message will be shown.
`StartPage`	Opens a new page (relevant only for printing / pdf etc.) with the given size in points.
`StrokeLine`	Strokes a single line.
`StrokeLineSegments`	Stroke disconnected lines from begin to end points.
`StrokeLines`	Stroke lines conencting all the points.
`StrokePath`	Strokes along a path with the current pen.
`Translate`	Translates the current transformation matrix.

Properties Summary¶

`AntialiasMode`	See `GetAntialiasMode` and `SetAntialiasMode`
`CompositionMode`	See `GetCompositionMode` and `SetCompositionMode`
`InterpolationQuality`	See `GetInterpolationQuality` and `SetInterpolationQuality`
`NativeContext`	See `GetNativeContext`
`TextExtent`	See `GetTextExtent`
`Transform`	See `GetTransform` and `SetTransform`

Class API¶

class wx.GraphicsContext(GraphicsObject)¶

A GraphicsContext instance is the object that is drawn upon.

Methods¶

BeginLayer(self, opacity)¶

Redirects all rendering is done into a fully transparent temporary context.

Parameters: opacity (wx.Double) –

Clip(self, *args, **kw)¶

Overloaded Implementations:

Clip (self, region)

Clips drawings to the specified region.

Parameters: region (wx.Region) –

Clip (self, x, y, w, h)

Clips drawings to the specified rectangle.

Parameters

x (wx.Double) –
y (wx.Double) –
w (wx.Double) –
h (wx.Double) –

ConcatTransform(self, matrix)¶

Concatenates the passed in transform with the current transform of this context.

Parameters: matrix (wx.GraphicsMatrix) –

static Create(*args, **kw)¶

Overloaded Implementations:

Create (window)

Creates a wx.GraphicsContext from a wx.Window.

Parameters: window (wx.Window) –
Return type: wx.GraphicsContext

See also

wx.GraphicsRenderer.CreateContext

Create (windowDC)

Creates a wx.GraphicsContext from a wx.WindowDC.

Parameters: windowDC (wx.WindowDC) –
Return type: wx.GraphicsContext

See also

wx.GraphicsRenderer.CreateContext

Create (memoryDC)

Creates a wx.GraphicsContext from a wx.MemoryDC.

Parameters: memoryDC (wx.MemoryDC) –
Return type: wx.GraphicsContext

See also

wx.GraphicsRenderer.CreateContext

Create (printerDC)

Creates a wx.GraphicsContext from a wx.PrinterDC.

Under GTK+, this will only work when using the GtkPrint printing backend which is available since GTK+ 2.10.

Parameters: printerDC (wx.PrinterDC) –
Return type: wx.GraphicsContext

See also

wx.GraphicsRenderer.CreateContext ,

Create (metaFileDC)

Creates a wx.GraphicsContext from a EnhMetaFileDC.

This function, as EnhMetaFileDC class itself, is only available only under MSW.

Parameters: metaFileDC (MetafileDC) –
Return type: wx.GraphicsContext

See also

wx.GraphicsRenderer.CreateContext

Create (image)

Creates a wx.GraphicsContext associated with a wx.Image.

The image specifies the size of the context as well as whether alpha is supported (if wx.Image.HasAlpha ) or not and the initial contents of the context. The image object must have a life time greater than that of the new context as the context copies its contents back to the image when it is destroyed.

Parameters: image (wx.Image) –
Return type: wx.GraphicsContext

New in version 2.9.3.

Create ()

Create a lightweight context that can be used only for measuring text.

Return type: wx.GraphicsContext

Create (autoPaintDC)

Return type: wx.GraphicsContext

CreateBitmap(self, bitmap)¶

Creates wx.GraphicsBitmap from an existing wx.Bitmap.

Returns an invalid NullGraphicsBitmap on failure.

Parameters: bitmap (wx.Bitmap) –
Return type: wx.GraphicsBitmap

CreateBitmapFromImage(self, image)¶

Creates wx.GraphicsBitmap from an existing wx.Image.

This method is more efficient than converting wx.Image to wx.Bitmap first and then calling CreateBitmap but otherwise has the same effect.

Returns an invalid NullGraphicsBitmap on failure.

Parameters: image (wx.Image) –
Return type: wx.GraphicsBitmap

New in version 2.9.3.

CreateBrush(self, brush)¶

Creates a native brush from a wx.Brush.

Parameters: brush (wx.Brush) –
Return type: wx.GraphicsBrush

CreateFont(self, *args, **kw)¶

Overloaded Implementations:

CreateFont (self, font, col=BLACK)

Creates a native graphics font from a wx.Font and a text colour.

Parameters

font (wx.Font) –
col (wx.Colour) –

Return type

wx.GraphicsFont

CreateFont (self, sizeInPixels, facename, flags=FONTFLAG_DEFAULT, col=BLACK)

Creates a font object with the specified attributes.

The use of overload taking wx.Font is preferred, see wx.GraphicsRenderer.CreateFont for more details.

Parameters

sizeInPixels (float) –
facename (string) –
flags (int) –
col (wx.Colour) –

Return type

wx.GraphicsFont

New in version 2.9.3.

static CreateFromNative(context)¶

Creates a wx.GraphicsContext from a native context.

This native context must be a CGContextRef for Core Graphics, a Graphics pointer for GDIPlus, or a cairo_t pointer for cairo.

Parameters: context –
Return type: wx.GraphicsContext

static CreateFromNativeWindow(window)¶

Creates a wx.GraphicsContext from a native window.

Parameters: window –
Return type: wx.GraphicsContext

CreateLinearGradientBrush(self, *args, **kw)¶

Creates a native brush with a linear gradient.

The brush starts at (x1, y1) and ends at (x2, y2). Either just the start and end gradient colours (c1 and c2) or full set of gradient stops can be specified.

The version taking wx.GraphicsGradientStops is new in wxWidgets 2.9.1.

Overloaded Implementations:

CreateLinearGradientBrush (self, x1, y1, x2, y2, c1, c2)

Parameters

x1 (wx.Double) –
y1 (wx.Double) –
x2 (wx.Double) –
y2 (wx.Double) –
c1 (wx.Colour) –
c2 (wx.Colour) –

Return type

wx.GraphicsBrush

CreateLinearGradientBrush (self, x1, y1, x2, y2, stops)

Parameters

x1 (wx.Double) –
y1 (wx.Double) –
x2 (wx.Double) –
y2 (wx.Double) –
stops (wx.GraphicsGradientStops) –

Return type

wx.GraphicsBrush

CreateMatrix(self, *args, **kw)¶

Overloaded Implementations:

CreateMatrix (self, a=1.0, b=0.0, c=0.0, d=1.0, tx=0.0, ty=0.0)

Creates a native affine transformation matrix from the passed in values.

The default parameters result in an identity matrix.

Parameters

a (wx.Double) –
b (wx.Double) –
c (wx.Double) –
d (wx.Double) –
tx (wx.Double) –
ty (wx.Double) –

Return type

wx.GraphicsMatrix

CreateMatrix (self, mat)

Creates a native affine transformation matrix from the passed generic one.

Parameters: mat (wx.AffineMatrix2DBase) –
Return type: wx.GraphicsMatrix

New in version 2.9.4.

CreatePath(self)¶

Creates a native graphics path which is initially empty.

Return type: wx.GraphicsPath

CreatePen(self, pen)¶

Creates a native pen from a wx.Pen.

Parameters: pen (wx.Pen) –
Return type: wx.GraphicsPen

CreateRadialGradientBrush(self, *args, **kw)¶

Creates a native brush with a radial gradient.

The brush originates at (xo, yc) and ends on a circle around (xc, yc) with the given radius.

The gradient may be specified either by its start and end colours oColor and cColor or by a full set of gradient stops.

The version taking wx.GraphicsGradientStops is new in wxWidgets 2.9.1.

Overloaded Implementations:

CreateRadialGradientBrush (self, xo, yo, xc, yc, radius, oColor, cColor)

Parameters

xo (wx.Double) –
yo (wx.Double) –
xc (wx.Double) –
yc (wx.Double) –
radius (wx.Double) –
oColor (wx.Colour) –
cColor (wx.Colour) –

Return type

wx.GraphicsBrush

CreateRadialGradientBrush (self, xo, yo, xc, yc, radius, stops)

Parameters

xo (wx.Double) –
yo (wx.Double) –
xc (wx.Double) –
yc (wx.Double) –
radius (wx.Double) –
stops (wx.GraphicsGradientStops) –

Return type

wx.GraphicsBrush

CreateSubBitmap(self, bitmap, x, y, w, h)¶

Extracts a sub-bitmap from an existing bitmap.

Currently this function is implemented in the native MSW and OS X versions but not when using Cairo.

Parameters

bitmap (wx.GraphicsBitmap) –
x (wx.Double) –
y (wx.Double) –
w (wx.Double) –
h (wx.Double) –

Return type

wx.GraphicsBitmap

DisableOffset(self)¶

DrawBitmap(self, *args, **kw)¶

Draws the bitmap.

In case of a mono bitmap, this is treated as a mask and the current brushed is used for filling.

Overloaded Implementations:

DrawBitmap (self, bmp, x, y, w, h)

Parameters

bmp (wx.GraphicsBitmap) –
x (wx.Double) –
y (wx.Double) –
w (wx.Double) –
h (wx.Double) –

DrawBitmap (self, bmp, x, y, w, h)

Parameters

bmp (wx.Bitmap) –
x (wx.Double) –
y (wx.Double) –
w (wx.Double) –
h (wx.Double) –

DrawEllipse(self, x, y, w, h)¶

Draws an ellipse.

Parameters

x (wx.Double) –
y (wx.Double) –
w (wx.Double) –
h (wx.Double) –

DrawIcon(self, icon, x, y, w, h)¶

Draws the icon.

Parameters

icon (wx.Icon) –
x (wx.Double) –
y (wx.Double) –
w (wx.Double) –
h (wx.Double) –

DrawLines(self, point2Ds, fillStyle=ODDEVEN_RULE)¶: Draws a polygon.

DrawPath(self, path, fillStyle=ODDEVEN_RULE)¶

Draws the path by first filling and then stroking.

Parameters

path (wx.GraphicsPath) –
fillStyle (PolygonFillMode) –

DrawRectangle(self, x, y, w, h)¶

Draws a rectangle.

Parameters

x (wx.Double) –
y (wx.Double) –
w (wx.Double) –
h (wx.Double) –

DrawRoundedRectangle(self, x, y, w, h, radius)¶

Draws a rounded rectangle.

Parameters

x (wx.Double) –
y (wx.Double) –
w (wx.Double) –
h (wx.Double) –
radius (wx.Double) –

DrawText(self, *args, **kw)¶

Overloaded Implementations:

DrawText (self, str, x, y)

Draws text at the defined position.

Parameters

str (string) –
x (wx.Double) –
y (wx.Double) –

DrawText (self, str, x, y, angle)

Draws text at the defined position.

Parameters

str (string) – The text to draw.
x (wx.Double) – The x coordinate position to draw the text at.
y (wx.Double) – The y coordinate position to draw the text at.
angle (wx.Double) – The angle relative to the (default) horizontal direction to draw the string.

DrawText (self, str, x, y, backgroundBrush)

Draws text at the defined position.

Parameters

str (string) – The text to draw.
x (wx.Double) – The x coordinate position to draw the text at.
y (wx.Double) – The y coordinate position to draw the text at.
backgroundBrush (wx.GraphicsBrush) – Brush to fill the text with.

DrawText (self, str, x, y, angle, backgroundBrush)

Draws text at the defined position.

Parameters

str (string) – The text to draw.
x (wx.Double) – The x coordinate position to draw the text at.
y (wx.Double) – The y coordinate position to draw the text at.
angle (wx.Double) – The angle relative to the (default) horizontal direction to draw the string.
backgroundBrush (wx.GraphicsBrush) – Brush to fill the text with.

EnableOffset(self, enable=True)¶

Parameters: enable (bool) –

EndDoc(self)¶: Done with that document (relevant only for printing / pdf etc.)

EndLayer(self)¶: Composites back the drawings into the context with the opacity given at the BeginLayer call.

EndPage(self)¶: Ends the current page (relevant only for printing / pdf etc.)

FillPath(self, path, fillStyle=ODDEVEN_RULE)¶

Fills the path with the current brush.

Parameters

path (wx.GraphicsPath) –
fillStyle (PolygonFillMode) –

Flush(self)¶: Make sure that the current content of this context is immediately visible.

GetAntialiasMode(self)¶

Returns the current shape antialiasing mode.

Return type: wx.AntialiasMode

GetCompositionMode(self)¶

Returns the current compositing operator.

Return type: wx.CompositionMode

GetDPI(self)¶

Returns the resolution of the graphics context in device points per inch.

Return type: tuple
Returns: ( dpiX, dpiY )

GetInterpolationQuality(self)¶

Returns the current interpolation quality.

Return type: wx.InterpolationQuality

GetNativeContext(self)¶: Returns the native context (CGContextRef for Core Graphics, Graphics pointer for GDIPlus and cairo_t pointer for cairo).

GetPartialTextExtents(self, text)¶

Fills the widths array with the widths from the beginning of text to the corresponding character of text.

Parameters: text (string) –
Return type: list of floats

GetSize(self)¶

Returns the size of the graphics context in device coordinates.

Return type: tuple
Returns: ( width, height )

GetFullTextExtent(self, *args, **kw)¶

Overloaded Implementations:

GetFullTextExtent (self, text)

Gets the dimensions of the string using the currently selected font.

Parameters: text (string) – The text string to measure.
Return type: tuple
Returns: ( width, height, descent, externalLeading )

GetFullTextExtent (self, text)

Gets the dimensions of the string using the currently selected font.

Return type: tuple
Returns: ( width, height )

GetTransform(self)¶

Gets the current transformation matrix of this context.

Return type: wx.GraphicsMatrix

OffsetEnabled(self)¶

Return type: bool

PopState(self)¶: Pops a stored state from the stack and sets the current transformation matrix to that state.

See also

wx.GraphicsContext.PopState

PushState(self)¶: Push the current state of the context’s transformation matrix on a stack.

See also

wx.GraphicsContext.PopState

ResetClip(self)¶: Resets the clipping to original shape.

Rotate(self, angle)¶

Rotates the current transformation matrix (in radians).

Parameters: angle (wx.Double) –

Scale(self, xScale, yScale)¶

Scales the current transformation matrix.

Parameters

xScale (wx.Double) –
yScale (wx.Double) –

SetAntialiasMode(self, antialias)¶

Sets the antialiasing mode, returns True if it supported.

Parameters: antialias (AntialiasMode) –
Return type: bool

SetBrush(self, *args, **kw)¶

Sets the brush for filling paths.

Overloaded Implementations:

SetBrush (self, brush)

Parameters: brush (wx.Brush) –

SetBrush (self, brush)

Parameters: brush (wx.GraphicsBrush) –

SetCompositionMode(self, op)¶

Sets the compositing operator, returns True if it supported.

Parameters: op (CompositionMode) –
Return type: bool

SetFont(self, *args, **kw)¶

Sets the font for drawing text.

Overloaded Implementations:

SetFont (self, font, colour)

Parameters

font (wx.Font) –
colour (wx.Colour) –

SetFont (self, font)

Parameters: font (wx.GraphicsFont) –

SetInterpolationQuality(self, interpolation)¶

Sets the interpolation quality, returns True if it is supported.

Not implemented in Cairo backend currently.

Notice that in wxWidgets 3.0 the default interpolation quality for GDI+-based implementation is INTERPOLATION_GOOD and not INTERPOLATION_DEFAULT (unlike under OS X with CoreGraphics-based implementation). This will be changed in wxWidgets 3.1 and later version, call this method explicitly instead of relying on the default value to ensure consistent behaviour across different platforms and versions.

Parameters: interpolation (InterpolationQuality) –
Return type: bool

SetPen(self, *args, **kw)¶

Sets the pen used for stroking.

Overloaded Implementations:

SetPen (self, pen)

Parameters: pen (wx.Pen) –

SetPen (self, pen)

Parameters: pen (wx.GraphicsPen) –

SetTransform(self, matrix)¶

Sets the current transformation matrix of this context.

Parameters: matrix (wx.GraphicsMatrix) –

ShouldOffset(self)¶

Return type: bool

StartDoc(self, message)¶

Begin a new document (relevant only for printing / pdf etc.) If there is a progress dialog, message will be shown.

Parameters: message (string) –
Return type: bool

StartPage(self, width=0, height=0)¶

Opens a new page (relevant only for printing / pdf etc.) with the given size in points.

(If both are null the default page size will be used.)

Parameters

width (wx.Double) –
height (wx.Double) –

StrokeLine(self, x1, y1, x2, y2)¶

Strokes a single line.

Parameters

x1 (wx.Double) –
y1 (wx.Double) –
x2 (wx.Double) –
y2 (wx.Double) –

StrokeLineSegments(self, beginPoint2Ds, endPoint2Ds)¶: Stroke disconnected lines from begin to end points.

StrokeLines(self, point2Ds)¶: Stroke lines conencting all the points.

StrokePath(self, path)¶

Strokes along a path with the current pen.

Parameters: path (wx.GraphicsPath) –

Translate(self, dx, dy)¶

Translates the current transformation matrix.

Parameters

dx (wx.Double) –
dy (wx.Double) –

Properties¶

AntialiasMode¶: See GetAntialiasMode and SetAntialiasMode

CompositionMode¶: See GetCompositionMode and SetCompositionMode

InterpolationQuality¶: See GetInterpolationQuality and SetInterpolationQuality

NativeContext¶: See GetNativeContext

TextExtent¶: See GetTextExtent

Transform¶: See GetTransform and SetTransform

Navigation

wx.GraphicsContext¶

Class Hierarchy¶

Methods Summary¶

Properties Summary¶

Class API¶

Methods¶

Properties¶