EMF::METAFILEDEVICECONTEXT Class Reference

Graphics Device Context. More...

#include <libemf.h>

Inheritance diagram for EMF::METAFILEDEVICECONTEXT:

Public Member Functions
	METAFILEDEVICECONTEXT (FILE *fp_, const RECT *size, LPCWSTR description_w)
virtual	~METAFILEDEVICECONTEXT ()
OBJECTTYPE	getType (void) const
DWORD	nextHandle (void)
void	clearHandle (DWORD handle)
void	appendRecord (METARECORD *record)
void	appendHandle (METARECORD *record)
void	deleteMetafile (void)
void	mergePoint (const LONG &x, const LONG &y)
void	mergePoint (const POINT &p)
Public Member Functions inherited from EMF::OBJECT
virtual	~OBJECT ()
	OBJECTs have a virtual destructor.
	OBJECT (void)

Public Attributes
::FILE *	fp
DATASTREAM	ds
ENHMETAHEADER *	header
std::vector< EMF::METARECORD * >	records
SIZEL	resolution
	The resolution in DPI of the reference DC.
SIZEL	viewport_ext
	The extent of the viewport.
POINT	viewport_org
	The origin of the viewport.
SIZEL	window_ext
	The extent of the window.
POINT	window_org
	The origin of the window.
bool	update_frame
	Update the frame automatically?
POINT	min_device_point
	The lft/top-most painted point in device units.
POINT	max_device_point
	The rgt/btm-most painted point in device units.
POINT	point
	The current point.
PEN *	pen
	The current pen.
BRUSH *	brush
	The current brush.
FONT *	font
	The current font.
PALETTE *	palette
	The current palette.
UINT	text_alignment
	The current text alignment.
COLORREF	text_color
	The current text foreground color.
COLORREF	bk_color
	The current background color.
INT	bk_mode
	The current background mode.
INT	polyfill_mode
	The current polygon fill mode.
INT	map_mode
	The current mapping mode.
FLOAT	miter_limit
	The current miter length limit.
std::vector< bool >	handles
std::map< HGDIOBJ, HGDIOBJ >	emf_handles
Public Attributes inherited from EMF::OBJECT
HGDIOBJ	handle

Detailed Description

Graphics Device Context.

Almost all GDI graphics calls require a device context (except those which create graphics objects such as pens and fonts). This is a specific context which renders to a metafile. There is a one-to-one correspondence between the device context and the metafile.

Constructor & Destructor Documentation

METAFILEDEVICECONTEXT()

EMF::METAFILEDEVICECONTEXT::METAFILEDEVICECONTEXT ( FILE * fp_, const RECT * size, LPCWSTR description_w )

inline

Most graphics programs seem to want to handle the opening and closing of files themselves, so this is an extension to the w32 interface.

Parameters

fp_	stdio pointer to an open file. May be null.
size	the rectangle describing the position and size of the metafile on the "page". May be null.
description_w	a UNICODE string describing the metafile. The format must be "some text\0some more text\0\0". May be null.

~METAFILEDEVICECONTEXT()

virtual EMF::METAFILEDEVICECONTEXT::~METAFILEDEVICECONTEXT ( )

inlinevirtual

Destructor frees all the graphics objects which may have been allocated. Now, it also frees any metarecords which it might hold, too.

Member Function Documentation

appendHandle()

void EMF::METAFILEDEVICECONTEXT::appendHandle ( METARECORD * record )

inline

Add this record to the metafile.

Parameters

record

this record is an object so it increments the handle count as well.

appendRecord()

void EMF::METAFILEDEVICECONTEXT::appendRecord ( METARECORD * record )

inline

Add this record to the metafile.

Parameters

record

standard graphics record

clearHandle()

void EMF::METAFILEDEVICECONTEXT::clearHandle ( DWORD handle )

inline

Clear the usage of this handle

deleteMetafile()

void EMF::METAFILEDEVICECONTEXT::deleteMetafile ( void )

inline

Delete all the records from the metafile. This would seem to include deleting the header record as well.

getType()

OBJECTTYPE EMF::METAFILEDEVICECONTEXT::getType ( void ) const

inlinevirtual

Return the type of this object (could probably do better with RTTI()).

Implements EMF::OBJECT.

mergePoint() [1/2]

void EMF::METAFILEDEVICECONTEXT::mergePoint ( const LONG & x, const LONG & y )

inline

Somewhat superfluous, except checker doesn't understand the initialization of automatic structures in the declaration.

mergePoint() [2/2]

void EMF::METAFILEDEVICECONTEXT::mergePoint ( const POINT & p )

inline

Take the given point and determine if it enlarges the "painted" area of the device.

nextHandle()

DWORD EMF::METAFILEDEVICECONTEXT::nextHandle ( void )

inline

Scan the bit vector of used handles and return the index of the first free bit as this objects metafile handle.

Member Data Documentation

ds

DATASTREAM EMF::METAFILEDEVICECONTEXT::ds

All i/o to the metafile is wrapped by this class so that byte swapping on big-endian machines is transparent.

emf_handles

std::map< HGDIOBJ, HGDIOBJ > EMF::METAFILEDEVICECONTEXT::emf_handles

This map holds the current mapping between EMF handles and global object handles as a metafile is played back (with PlayEnhMetaFile).

fp

::FILE* EMF::METAFILEDEVICECONTEXT::fp

If it is a file-based metafile, then this pointer is not null.

handles

std::vector< bool > EMF::METAFILEDEVICECONTEXT::handles

For compatibility, it appears that metafile handles are reused as objects are deleted. Attempt to emulate that behavior with a bit vector of used metafile handles.

header

ENHMETAHEADER* EMF::METAFILEDEVICECONTEXT::header

Serves double duty as the physical device description.

records

std::vector< EMF::METARECORD* > EMF::METAFILEDEVICECONTEXT::records

All of the metafile records are stored in memory.

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The documentation for this class was generated from the following file:

• libemf.h