.TH "EMF::METAFILEDEVICECONTEXT" 3 "Wed Jun 29 2022" "Version 1.0.9" "libemf" \" -*- nroff -*-
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.SH NAME
EMF::METAFILEDEVICECONTEXT \- Graphics Device Context\&.  

.SH SYNOPSIS
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.PP
.PP
\fC#include <libemf\&.h>\fP
.PP
Inherits \fBEMF::OBJECT\fP\&.
.SS "Public Member Functions"

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.RI "\fBMETAFILEDEVICECONTEXT\fP (FILE *fp_, const RECT *size, LPCWSTR description_w)"
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.RI "virtual \fB~METAFILEDEVICECONTEXT\fP ()"
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.RI "OBJECTTYPE \fBgetType\fP (void) const"
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.RI "DWORD \fBnextHandle\fP (void)"
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.RI "void \fBclearHandle\fP (DWORD \fBhandle\fP)"
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.RI "void \fBappendRecord\fP (\fBMETARECORD\fP *record)"
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.RI "void \fBappendHandle\fP (\fBMETARECORD\fP *record)"
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.RI "void \fBdeleteMetafile\fP (void)"
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.RI "void \fBmergePoint\fP (const LONG &x, const LONG &y)"
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.RI "void \fBmergePoint\fP (const POINT &p)"
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.SS "Data Fields"

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.RI "::FILE * \fBfp\fP"
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.RI "\fBDATASTREAM\fP \fBds\fP"
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.RI "\fBENHMETAHEADER\fP * \fBheader\fP"
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.RI "std::vector< \fBEMF::METARECORD\fP * > \fBrecords\fP"
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.RI "SIZEL \fBresolution\fP"
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.RI "The resolution in DPI of the \fIreference\fP DC\&. "
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.RI "SIZEL \fBviewport_ext\fP"
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.RI "The extent of the viewport\&. "
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.RI "POINT \fBviewport_org\fP"
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.RI "The origin of the viewport\&. "
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.RI "SIZEL \fBwindow_ext\fP"
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.RI "The extent of the window\&. "
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.RI "POINT \fBwindow_org\fP"
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.RI "The origin of the window\&. "
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.RI "bool \fBupdate_frame\fP"
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.RI "Update the frame automatically? "
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.RI "POINT \fBmin_device_point\fP"
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.RI "The lft/top-most painted point in device units\&. "
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.RI "POINT \fBmax_device_point\fP"
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.RI "The rgt/btm-most painted point in device units\&. "
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.RI "POINT \fBpoint\fP"
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.RI "The current point\&. "
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.RI "\fBPEN\fP * \fBpen\fP"
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.RI "The current pen\&. "
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.RI "\fBBRUSH\fP * \fBbrush\fP"
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.RI "The current brush\&. "
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.RI "\fBFONT\fP * \fBfont\fP"
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.RI "The current font\&. "
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.RI "\fBPALETTE\fP * \fBpalette\fP"
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.RI "The current palette\&. "
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.RI "UINT \fBtext_alignment\fP"
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.RI "The current text alignment\&. "
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.RI "COLORREF \fBtext_color\fP"
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.RI "The current text foreground color\&. "
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.RI "COLORREF \fBbk_color\fP"
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.RI "The current background color\&. "
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.RI "INT \fBbk_mode\fP"
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.RI "The current background mode\&. "
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.RI "INT \fBpolyfill_mode\fP"
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.RI "The current polygon fill mode\&. "
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.RI "INT \fBmap_mode\fP"
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.RI "The current mapping mode\&. "
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.RI "FLOAT \fBmiter_limit\fP"
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.RI "The current miter length limit\&. "
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.RI "std::vector< bool > \fBhandles\fP"
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.RI "std::map< HGDIOBJ, HGDIOBJ > \fBemf_handles\fP"
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.SH "Detailed Description"
.PP 
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\&. 
.SH "Constructor & Destructor Documentation"
.PP 
.SS "EMF::METAFILEDEVICECONTEXT::METAFILEDEVICECONTEXT (FILE * fp_, const RECT * size, LPCWSTR description_w)\fC [inline]\fP"
Most graphics programs seem to want to handle the opening and closing of files themselves, so this is an extension to the w32 interface\&.
.PP
\fBParameters\fP
.RS 4
\fIfp_\fP stdio pointer to an open file\&. May be null\&. 
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\fIsize\fP the rectangle describing the position and size of the metafile on the 'page'\&. May be null\&. 
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\fIdescription_w\fP a UNICODE string describing the metafile\&. The format must be 'some text\\0some more text\\0\\0'\&. May be null\&. 
.RE
.PP

.SS "virtual EMF::METAFILEDEVICECONTEXT::~METAFILEDEVICECONTEXT ()\fC [inline]\fP, \fC [virtual]\fP"
Destructor frees all the graphics objects which may have been allocated\&. Now, it also frees any metarecords which it might hold, too\&. 
.PP
References deleteMetafile(), and records\&.
.SH "Member Function Documentation"
.PP 
.SS "void EMF::METAFILEDEVICECONTEXT::appendHandle (\fBMETARECORD\fP * record)\fC [inline]\fP"
Add this record to the metafile\&.
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\fBParameters\fP
.RS 4
\fIrecord\fP this record is an object so it increments the handle count as well\&. 
.RE
.PP

.PP
References header, records, and EMF::METARECORD::size()\&.
.SS "void EMF::METAFILEDEVICECONTEXT::appendRecord (\fBMETARECORD\fP * record)\fC [inline]\fP"
Add this record to the metafile\&.
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\fBParameters\fP
.RS 4
\fIrecord\fP standard graphics record 
.RE
.PP

.PP
References header, records, and EMF::METARECORD::size()\&.
.SS "void EMF::METAFILEDEVICECONTEXT::clearHandle (DWORD handle)\fC [inline]\fP"
Clear the usage of this handle 
.PP
References EMF::OBJECT::handle, and handles\&.
.SS "void EMF::METAFILEDEVICECONTEXT::deleteMetafile (void)\fC [inline]\fP"
Delete all the records from the metafile\&. This would seem to include deleting the header record as well\&. 
.PP
References records\&.
.PP
Referenced by ~METAFILEDEVICECONTEXT()\&.
.SS "OBJECTTYPE EMF::METAFILEDEVICECONTEXT::getType (void) const\fC [inline]\fP, \fC [virtual]\fP"
Return the type of this object (could probably do better with RTTI())\&. 
.PP
Implements \fBEMF::OBJECT\fP\&.
.SS "void EMF::METAFILEDEVICECONTEXT::mergePoint (const LONG & x, const LONG & y)\fC [inline]\fP"
Somewhat superfluous, except checker doesn't understand the initialization of automatic structures in the declaration\&. 
.SS "void EMF::METAFILEDEVICECONTEXT::mergePoint (const POINT & p)\fC [inline]\fP"
Take the given point and determine if it enlarges the 'painted' area of the device\&. 
.PP
References header, max_device_point, min_device_point, update_frame, viewport_ext, viewport_org, window_ext, and window_org\&.
.SS "DWORD EMF::METAFILEDEVICECONTEXT::nextHandle (void)\fC [inline]\fP"
Scan the bit vector of used handles and return the index of the first free bit as this objects metafile handle\&. 
.PP
References handles, and header\&.
.SH "Field Documentation"
.PP 
.SS "\fBDATASTREAM\fP EMF::METAFILEDEVICECONTEXT::ds"
All i/o to the metafile is wrapped by this class so that byte swapping on big-endian machines is transparent\&. 
.SS "std::map< HGDIOBJ, HGDIOBJ > EMF::METAFILEDEVICECONTEXT::emf_handles"
This map holds the \fIcurrent\fP mapping between EMF handles and global object handles as a metafile is played back (with PlayEnhMetaFile)\&. 
.PP
Referenced by EMF::EMRSELECTOBJECT::execute(), EMF::EMRDELETEOBJECT::execute(), EMF::EMRCREATEPEN::execute(), EMF::EMREXTCREATEPEN::execute(), EMF::EMRCREATEBRUSHINDIRECT::execute(), and EMF::EMREXTCREATEFONTINDIRECTW::execute()\&.
.SS "::FILE* EMF::METAFILEDEVICECONTEXT::fp"
If it is a file-based metafile, then this pointer is not null\&. 
.SS "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\&. 
.PP
Referenced by clearHandle(), and nextHandle()\&.
.SS "\fBENHMETAHEADER\fP* EMF::METAFILEDEVICECONTEXT::header"
Serves double duty as the physical device description\&. 
.PP
Referenced by appendHandle(), appendRecord(), mergePoint(), and nextHandle()\&.
.SS "std::vector< \fBEMF::METARECORD\fP* > EMF::METAFILEDEVICECONTEXT::records"
All of the metafile records are stored in memory\&. 
.PP
Referenced by appendHandle(), appendRecord(), deleteMetafile(), and ~METAFILEDEVICECONTEXT()\&.

.SH "Author"
.PP 
Generated automatically by Doxygen for libemf from the source code\&.