wxSVGGraphicsContext Class Reference

#include <wx/svggc.h>

Inheritance diagram for wxSVGGraphicsContext:

Detailed Description

wxSVGGraphicsContext is a specialized wxGraphicsContext that allows drawing to an SVG file using the wxGraphicsContext API.

This context provides access to advanced vector features not available in the standard wxDC API, such as cubic and quadratic Bézier curves, gradient brushes, and alpha blending.

This context is used when using wxGraphicsContext on a wxSVGFileDC.

Example of use:

wxSVGGraphicsContext gc("output.svg", 800, 600);
gc.SetPen(*wxRED_PEN);
gc.SetBrush(*wxCYAN_BRUSH);
gc.DrawRectangle(10, 10, 100, 100);
 
// Draw a Bézier curve
wxGraphicsPath path = gc.CreatePath();
path.MoveToPoint(150, 50);
path.AddCurveToPoint(200, 0, 250, 100, 300, 50);
gc.StrokePath(path);

Library:  wxCore

Category:  Graphics Device Interface (GDI)

Since

3.3.3

Public Member Functions
	wxSVGGraphicsContext (wxSVGFileDC &dc)
	Constructor.
	wxSVGGraphicsContext (const wxString &filename, int width=320, int height=240, double dpi=wxSVG_DEFAULT_DPI, const wxString &title=wxString())
	Constructor for creating an SVG file directly.
	wxSVGGraphicsContext (const wxSize &size, const wxString &filename=wxString(), const wxString &title=wxString(), double dpi=wxSVG_DEFAULT_DPI)
	Constructor for creating an SVG file directly.
wxString	GetSVGDocument () const
	Returns the SVG document as a string.
bool	Save ()
	Writes the document to the configured filename.
void	SetBitmapHandler (wxSVGBitmapHandler *handler)
	Sets a handler for bitmap processing (e.g., embedding).
virtual void *	GetNativeContext () override
	This method is not applicable to the SVG renderer and always returns nullptr.
virtual bool	SetAntialiasMode (wxAntialiasMode antialias) override
	Sets the antialiasing mode.
virtual bool	SetInterpolationQuality (wxInterpolationQuality interpolation) override
	Sets the interpolation quality.
virtual bool	SetCompositionMode (wxCompositionMode op) override
	Sets the composition mode.
Paint state
virtual void	SetPen (const wxGraphicsPen &pen) override
	Sets the pen used for stroking.
virtual void	SetBrush (const wxGraphicsBrush &brush) override
	Sets the brush for filling paths.
Public Member Functions inherited from wxGraphicsContext
virtual void	ResetClip ()=0
	Resets the clipping to original shape.
virtual void	Clip (const wxRegion &region)=0
	Sets the clipping region to the intersection of the given region and the previously set clipping region.
virtual void	Clip (wxDouble x, wxDouble y, wxDouble w, wxDouble h)=0
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
void	Clip (const wxRect2DDouble &rect)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
virtual void	GetClipBox (wxDouble *x, wxDouble *y, wxDouble *w, wxDouble *h)=0
	Returns a bounding box of the current clipping region.
wxRect2DDouble	GetClipBox ()
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
virtual wxGraphicsMatrix	CreateMatrix (wxDouble a=1.0, wxDouble b=0.0, wxDouble c=0.0, wxDouble d=1.0, wxDouble tx=0.0, wxDouble ty=0.0) const
	Creates a native affine transformation matrix from the passed-in values.
wxGraphicsMatrix	CreateMatrix (const wxAffineMatrix2DBase &mat) const
	Creates a native affine transformation matrix from the passed generic one.
virtual void	ConcatTransform (const wxGraphicsMatrix &matrix)=0
	Concatenates the passed-in transform with the current transform of this context.
virtual wxGraphicsMatrix	GetTransform () const =0
	Gets the current transformation matrix of this context.
virtual void	Rotate (wxDouble angle)=0
	Rotates the current transformation matrix (in radians).
virtual void	Scale (wxDouble xScale, wxDouble yScale)=0
	Scales (i.e., shrinks or grows) the current transformation matrix.
virtual void	SetTransform (const wxGraphicsMatrix &matrix)=0
	Sets the current transformation matrix of this context.
virtual void	Translate (wxDouble dx, wxDouble dy)=0
	Translates (i.e., moves) the current transformation matrix.
void	Translate (const wxPoint2DDouble &pt)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
virtual wxGraphicsBrush	CreateBrush (const wxBrush &brush) const
	Creates a native brush from a wxBrush.
wxGraphicsBrush	CreateLinearGradientBrush (wxDouble x1, wxDouble y1, wxDouble x2, wxDouble y2, const wxColour &c1, const wxColour &c2, const wxGraphicsMatrix &matrix=wxNullGraphicsMatrix) const
	Creates a native brush with a linear gradient.
wxGraphicsBrush	CreateLinearGradientBrush (wxDouble x1, wxDouble y1, wxDouble x2, wxDouble y2, const wxGraphicsGradientStops &stops, const wxGraphicsMatrix &matrix=wxNullGraphicsMatrix) const
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
virtual wxGraphicsBrush	CreateRadialGradientBrush (wxDouble startX, wxDouble startY, wxDouble endX, wxDouble endY, wxDouble radius, const wxColour &oColor, const wxColour &cColor, const wxGraphicsMatrix &matrix=wxNullGraphicsMatrix) const
	Creates a native brush with a radial gradient.
virtual wxGraphicsBrush	CreateRadialGradientBrush (wxDouble startX, wxDouble startY, wxDouble endX, wxDouble endY, wxDouble radius, const wxGraphicsGradientStops &stops, const wxGraphicsMatrix &matrix=wxNullGraphicsMatrix)=0
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
void	SetBrush (const wxBrush &brush)
	Sets the brush for filling paths.
wxGraphicsPen	CreatePen (const wxPen &pen) const
	Creates a native pen from a wxPen.
wxGraphicsPen	CreatePen (const wxGraphicsPenInfo &info) const
	Creates a native pen from a wxGraphicsPenInfo.
void	SetPen (const wxPen &pen)
	Sets the pen used for stroking.
virtual void	DrawBitmap (const wxGraphicsBitmap &bmp, wxDouble x, wxDouble y, wxDouble w, wxDouble h)=0
	Draws the bitmap.
virtual void	DrawBitmap (const wxBitmap &bmp, wxDouble x, wxDouble y, wxDouble w, wxDouble h)=0
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
void	DrawBitmap (const wxGraphicsBitmap &bmp, const wxRect2DDouble &rect)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
virtual void	DrawEllipse (wxDouble x, wxDouble y, wxDouble w, wxDouble h)
	Draws an ellipse.
void	DrawEllipse (const wxRect2DDouble &rect)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
virtual void	DrawIcon (const wxIcon &icon, wxDouble x, wxDouble y, wxDouble w, wxDouble h)=0
	Draws the icon.
void	DrawIcon (const wxIcon &icon, const wxRect2DDouble &rect)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
virtual void	DrawLines (size_t n, const wxPoint2DDouble *points, wxPolygonFillMode fillStyle=wxODDEVEN_RULE)
	Draws a polygon.
virtual void	DrawPath (const wxGraphicsPath &path, wxPolygonFillMode fillStyle=wxODDEVEN_RULE)
	Draws the path by first filling and then stroking.
virtual void	DrawRectangle (wxDouble x, wxDouble y, wxDouble w, wxDouble h)
	Draws a rectangle.
void	DrawRectangle (const wxRect2DDouble &rect)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
virtual void	DrawRoundedRectangle (wxDouble x, wxDouble y, wxDouble w, wxDouble h, wxDouble radius)
	Draws a rounded rectangle.
void	DrawRoundedRectangle (const wxRect2DDouble &rect, wxDouble radius)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
void	DrawText (const wxString &str, wxDouble x, wxDouble y)
	Draws text at the defined position.
void	DrawText (const wxString &str, const wxPoint2DDouble &pt)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
void	DrawText (const wxString &str, wxDouble x, wxDouble y, wxDouble angle)
	Draws text at the defined position.
void	DrawText (const wxString &str, wxDouble x, wxDouble y, const wxGraphicsBrush &backgroundBrush)
	Draws text at the defined position.
void	DrawText (const wxString &str, wxDouble x, wxDouble y, wxDouble angle, const wxGraphicsBrush &backgroundBrush)
	Draws text at the defined position.
virtual void	ClearRectangle (wxDouble x, wxDouble y, wxDouble w, wxDouble h)
	Paints a transparent rectangle (only useful for bitmaps or windows).
void	ClearRectangle (const wxRect2DDouble &rect)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
wxGraphicsPath	CreatePath () const
	Creates a native graphics path which is initially empty.
virtual void	FillPath (const wxGraphicsPath &path, wxPolygonFillMode fillStyle=wxODDEVEN_RULE)=0
	Fills the path with the current brush.
virtual void	StrokeLine (wxDouble x1, wxDouble y1, wxDouble x2, wxDouble y2)
	Strokes a single line.
void	StrokeLine (const wxPoint2DDouble &pt1, const wxPoint2DDouble &pt2)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
virtual void	StrokeLines (size_t n, const wxPoint2DDouble *beginPoints, const wxPoint2DDouble *endPoints)
	Stroke disconnected lines from begin to end points, using the fastest method available.
virtual void	StrokeLines (size_t n, const wxPoint2DDouble *points)
	Stroke lines connecting all the points.
virtual void	StrokePath (const wxGraphicsPath &path)=0
	Strokes along a path with the current pen.
virtual wxGraphicsFont	CreateFont (const wxFont &font, const wxColour &col= *wxBLACK) const
	Creates a native graphics font from a wxFont and a text colour.
virtual wxGraphicsFont	CreateFont (double sizeInPixels, const wxString &facename, int flags=wxFONTFLAG_DEFAULT, const wxColour &col= *wxBLACK) const
	Creates a font object with the specified attributes.
void	SetFont (const wxFont &font, const wxColour &colour)
	Sets the font for drawing text.
virtual void	SetFont (const wxGraphicsFont &font)
	Sets the font for drawing text.
virtual void	GetPartialTextExtents (const wxString &text, wxArrayDouble &widths) const =0
	Fills the widths array with the widths from the beginning of text to the corresponding character of text.
virtual void	GetTextExtent (const wxString &text, wxDouble *width, wxDouble *height, wxDouble *descent, wxDouble *externalLeading) const =0
	Gets the dimensions of the string using the currently selected font.
virtual bool	StartDoc (const wxString &message)
	Begin a new document (relevant only for printing / pdf / etc.) If there is a progress dialog, message will be shown.
virtual void	EndDoc ()
	Done with that document (relevant only for printing / pdf / etc.).
virtual void	StartPage (wxDouble width=0, wxDouble height=0)
	Opens a new page (relevant only for printing / pdf etc.) with the given size in points.
virtual void	EndPage ()
	Ends the current page (relevant only for printing / pdf / etc.).
virtual wxGraphicsBitmap	CreateBitmap (const wxBitmap &bitmap)=0
	Creates wxGraphicsBitmap from an existing wxBitmap.
virtual wxGraphicsBitmap	CreateBitmapFromImage (const wxImage &image)
	Creates wxGraphicsBitmap from an existing wxImage.
virtual wxGraphicsBitmap	CreateSubBitmap (const wxGraphicsBitmap &bitmap, wxDouble x, wxDouble y, wxDouble w, wxDouble h)=0
	Extracts a sub-bitmap from an existing bitmap.
virtual void	BeginLayer (wxDouble opacity)=0
	All rendering will be done into a fully transparent, temporary context.
virtual void	EndLayer ()=0
	Composites back the drawings into the context with the opacity given at the BeginLayer() call.
virtual void	PushState ()=0
	Push the current state (like transformations, clipping region and quality settings) of the context on a stack.
virtual void	PopState ()=0
	Sets current state of the context to the state saved by a preceding call to PushState() and removes that state from the stack of saved states.
virtual void	Flush ()
	Make sure that the current content of this context is immediately visible.
virtual wxAntialiasMode	GetAntialiasMode () const
	Returns the current shape antialiasing mode.
virtual wxInterpolationQuality	GetInterpolationQuality () const
	Returns the current interpolation quality.
virtual wxCompositionMode	GetCompositionMode () const
	Returns the current compositing operator.
void	GetSize (wxDouble *width, wxDouble *height) const
	Returns the size of the graphics context in device coordinates.
virtual void	GetDPI (wxDouble *dpiX, wxDouble *dpiY) const
	Returns the resolution of the graphics context in device points per inch.
wxWindow *	GetWindow () const
	Returns the associated window, if any.
virtual bool	ShouldOffset () const
	Helper to determine if a 0.5 offset should be applied for the drawing operation.
virtual void	EnableOffset (bool enable=true)
	Indicates whether the context should try to offset for pixel boundaries.
void	DisableOffset ()
	Helper to determine if a 0.5 offset should be applied for the drawing operation.
bool	OffsetEnabled () const
	Helper to determine if a 0.5 offset should be applied for the drawing operation.
wxSize	FromDIP (const wxSize &sz) const
	Convert DPI-independent pixel values to the value in pixels appropriate for the graphics context.
wxPoint	FromDIP (const wxPoint &pt) const
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
int	FromDIP (int d) const
	Convert DPI-independent value in pixels to the value in pixels appropriate for the graphics context.
wxSize	ToDIP (const wxSize &sz) const
	Convert pixel values of the current graphics context to DPI-independent pixel values.
wxPoint	ToDIP (const wxPoint &pt) const
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
int	ToDIP (int d) const
	Convert pixel values of the current graphics context to DPI-independent pixel values.
Public Member Functions inherited from wxGraphicsObject
wxGraphicsRenderer *	GetRenderer () const
	Returns the renderer that was used to create this instance, or nullptr if it has not been initialized yet.
bool	IsNull () const
Public Member Functions inherited from wxObject
	wxObject ()
	Default ctor; initializes to nullptr the internal reference data.
	wxObject (const wxObject &other)
	Copy ctor.
virtual	~wxObject ()
	Destructor.
virtual wxClassInfo *	GetClassInfo () const
	This virtual function is redefined for every class that requires run-time type information, when using the wxDECLARE_CLASS macro (or similar).
wxObjectRefData *	GetRefData () const
	Returns the wxObject::m_refData pointer, i.e. the data referenced by this object.
bool	IsKindOf (const wxClassInfo *info) const
	Determines whether this class is a subclass of (or the same class as) the given class.
bool	IsSameAs (const wxObject &obj) const
	Returns true if this object has the same data pointer as obj.
void	Ref (const wxObject &clone)
	Makes this object refer to the data in clone.
void	SetRefData (wxObjectRefData *data)
	Sets the wxObject::m_refData pointer.
void	UnRef ()
	Decrements the reference count in the associated data, and if it is zero, deletes the data.
void	UnShare ()
	This is the same of AllocExclusive() but this method is public.
void	operator delete (void *buf)
	The delete operator is defined for debugging versions of the library only, when the identifier __WXDEBUG__ is defined.
void *	operator new (size_t size, const wxString &filename=nullptr, int lineNum=0)
	The new operator is defined for debugging versions of the library only, when the identifier __WXDEBUG__ is defined.

Static Public Member Functions
static wxGraphicsContext *	Create (wxSVGFileDC &dc)
	Creates a graphics context that draws into the given SVG DC.
Static Public Member Functions inherited from wxGraphicsContext
static wxGraphicsContext *	Create (wxWindow *window)
	Creates a wxGraphicsContext from a wxWindow.
static wxGraphicsContext *	Create (const wxWindowDC &windowDC)
	Creates a wxGraphicsContext from a wxWindowDC.
static wxGraphicsContext *	Create (const wxMemoryDC &memoryDC)
	Creates a wxGraphicsContext from a wxMemoryDC.
static wxGraphicsContext *	Create (const wxPrinterDC &printerDC)
	Creates a wxGraphicsContext from a wxPrinterDC.
static wxGraphicsContext *	Create (const wxEnhMetaFileDC &metaFileDC)
	Creates a wxGraphicsContext from a wxEnhMetaFileDC.
static wxGraphicsContext *	CreateFromUnknownDC (wxDC &dc)
	Creates a wxGraphicsContext from a DC of unknown specific type.
static wxGraphicsContext *	Create (wxImage &image)
	Creates a wxGraphicsContext associated with a wxImage.
static wxGraphicsContext *	CreateFromNative (void *context)
	Creates a wxGraphicsContext from a native context.
static wxGraphicsContext *	CreateFromNativeWindow (void *window)
	Creates a wxGraphicsContext from a native window.
static wxGraphicsContext *	CreateFromNativeHDC (WXHDC dc)
	Creates a wxGraphicsContext from a native DC handle.
static wxGraphicsContext *	Create ()
	Create a lightweight context that can be used only for measuring text.

Additional Inherited Members
Protected Member Functions inherited from wxObject
void	AllocExclusive ()
	Ensure that this object's data is not shared with any other object.
virtual wxObjectRefData *	CreateRefData () const
	Creates a new instance of the wxObjectRefData-derived class specific to this object and returns it.
virtual wxObjectRefData *	CloneRefData (const wxObjectRefData *data) const
	Creates a new instance of the wxObjectRefData-derived class specific to this object and initializes it copying data.
Protected Attributes inherited from wxObject
wxObjectRefData *	m_refData
	Pointer to an object which is the object's reference-counted data.

Constructor & Destructor Documentation

wxSVGGraphicsContext() [1/3]

wxSVGGraphicsContext::wxSVGGraphicsContext ( wxSVGFileDC & dc )

explicit

Constructor.

The DC must outlive the context.

Since

3.3.3

wxSVGGraphicsContext() [2/3]

wxSVGGraphicsContext::wxSVGGraphicsContext ( const wxString & filename, int width = 320, int height = 240, double dpi = wxSVG_DEFAULT_DPI, const wxString & title = wxString() )

explicit

Constructor for creating an SVG file directly.

Since

3.3.3

wxSVGGraphicsContext() [3/3]

wxSVGGraphicsContext::wxSVGGraphicsContext	(	const wxSize &	size,
		const wxString &	filename = wxString(),
		const wxString &	title = wxString(),
		double	dpi = wxSVG_DEFAULT_DPI )

Constructor for creating an SVG file directly.

Since

3.3.3

Member Function Documentation

Create()

wxGraphicsContext * wxSVGGraphicsContext::Create ( wxSVGFileDC & dc )

static

Creates a graphics context that draws into the given SVG DC.

Equivalent to calling wxSVGFileDC::GetGraphicsContext(). The DC must outlive the returned context.

Example:

wxSVGFileDC dc("output.svg", 800, 600);
wxGraphicsContext* gc = wxSVGGraphicsContext::Create(dc);

Since

3.3.3

GetNativeContext()

virtual void * wxSVGGraphicsContext::GetNativeContext ( )

overridevirtual

This method is not applicable to the SVG renderer and always returns nullptr.

Implements wxGraphicsContext.

GetSVGDocument()

wxString wxSVGGraphicsContext::GetSVGDocument

(

)

const

Returns the SVG document as a string.

Since

3.3.3

Save()

bool wxSVGGraphicsContext::Save

(

)

Writes the document to the configured filename.

Returns

true if the file was written successfully, false otherwise.

Since

3.3.3

SetAntialiasMode()

virtual bool wxSVGGraphicsContext::SetAntialiasMode ( wxAntialiasMode antialias )

overridevirtual

Sets the antialiasing mode.

For the SVG renderer, this method maps the wxAntialiasMode to the SVG shape-rendering attribute. (For example, wxANTIALIAS_NONE maps to wxSVG_SHAPE_RENDERING_CRISP_EDGES.)

Returns true.

Implements wxGraphicsContext.

SetBitmapHandler()

void wxSVGGraphicsContext::SetBitmapHandler

(

wxSVGBitmapHandler *

handler

)

Sets a handler for bitmap processing (e.g., embedding).

Takes ownership of the handler.

Since

3.3.3

SetBrush()

virtual void wxSVGGraphicsContext::SetBrush ( const wxGraphicsBrush & brush )

overridevirtual

Sets the brush for filling paths.

Note

Stippled brush styles are not supported by the SVG renderer.

Reimplemented from wxGraphicsContext.

SetCompositionMode()

virtual bool wxSVGGraphicsContext::SetCompositionMode ( wxCompositionMode op )

overridevirtual

Sets the composition mode.

For the SVG renderer, the following modes are supported:

• wxCOMPOSITION_ADD
• wxCOMPOSITION_DIFF
• wxCOMPOSITION_OVER (the default)

Returns true if the mode is supported, false otherwise.

Implements wxGraphicsContext.

SetInterpolationQuality()

virtual bool wxSVGGraphicsContext::SetInterpolationQuality ( wxInterpolationQuality interpolation )

overridevirtual

Sets the interpolation quality.

For the SVG renderer, this method maps the wxInterpolationQuality to the SVG shape-rendering attribute as a quality hint. (For example, wxINTERPOLATION_BEST maps to wxSVG_SHAPE_RENDERING_GEOMETRIC_PRECISION.)

Returns true.

Implements wxGraphicsContext.

SetPen()

virtual void wxSVGGraphicsContext::SetPen ( const wxGraphicsPen & pen )

overridevirtual

Sets the pen used for stroking.

Note

Stippled pen styles are not supported by the SVG renderer.

Reimplemented from wxGraphicsContext.