Module Description

Additional region APIs...

Groups
	Region Numbers

Classes
struct	GdiPathData

Typedefs
typedef struct _gdiPathData *	PGdiPathData

Functions
int WINAPI	MapRegionToWindow (HRGN hRgn, HWND hWnd)

RGNDATA *WINAPI	AllocAndGetRegionData (IN HRGN hRgn, OPTOUT PRECT *ppRc)

RGNDATA *WINAPI	FreeRegionData (RGNDATA *pRgn)

void WINAPI	DumpRegionData (CSTR Title, HRGN hRgn)

bool WINAPI	GetGdiPathData (HDC hdc, OUT PGdiPathData pData)

void WINAPI	FreeGdiPathData (PGdiPathData pData)

bool WINAPI	GetGdiPathBounds (HDC hdc, PRECT pBounds)

HRGN WINAPI	GetGdiPathRgn (HDC hdc, OUT RGNDATA ppRgnData, OPTOUT RECT ppRgnRects)

void	OffsetPoints (POINT *Pts, UINT nPts, int dx, int dy)

void	OffsetRgnData (PRGNDATA prd, int dx, int dy)

void	SetIdentityMat2 (MAT2 *pm)

Class Documentation

◆ GdiPathData

struct GdiPathData

Data structure to use with GetGdiPathData().

Definition at line 2131 of file UtilFunc.h.

Class Members
LPPOINT	pPoint	Array of points.
LPBYTE	pType	Array of type specs for each point.
RECT	Bounds	Bounding rect for the whole path.
int	nPoints	Nr of elements in the pPoint and pType arrays.

Typedef Documentation

◆ PGdiPathData

typedef struct _gdiPathData * PGdiPathData

Data structure to use with GetGdiPathData().

Function Documentation

◆ MapRegionToWindow()

int WINAPI MapRegionToWindow	(	HRGN	hRgn,
		HWND	hWnd
	)

Offset the hRgn to hWnd.
The return value specifies the region's complexity. (See OffsetRgn().)
This function is primarily for use with GetRandomRgn().

Definition at line 610 of file GdiUtil.cpp.

◆ AllocAndGetRegionData()

RGNDATA* WINAPI AllocAndGetRegionData	(	IN HRGN	hRgn,
		OPTOUT PRECT *	ppRc
	)

Allocate a region data block and retrieve it with GetRegionData().
If provided, ppRc receives a pointer to the region's constituent RECTs.

Note:: Don't forget to FreeRegionData() when you're done.

◆ FreeRegionData()

RGNDATA* WINAPI FreeRegionData ( RGNDATA * pRgn )

Free an AllocAndGetRegionData() block.

Definition at line 629 of file GdiUtil.cpp.

◆ DumpRegionData()

void WINAPI DumpRegionData	(	CSTR	Title,
		HRGN	hRgn
	)

Dump region data to the debugger. (Only in uLib _DEBUG builds)

Definition at line 635 of file GdiUtil.cpp.

◆ GetGdiPathData()

bool WINAPI GetGdiPathData	(	HDC	hdc,
		OUT PGdiPathData	pData
	)

GetGdiPathData() retrieves the current path data from a display context.
The path data is returned in a form suitable for use with PolyDraw().
The caller must supply a GdiPathData struct, which is filled by the function.
Dispose the data with FreeGdiPathData() when done.

Note: GetPath() sometimes fails, with no error code, even when there is a valid path.
I.e: GetPath( hdc, 0,0,0 ) == -1, and GetLastError() == 0.
Converting the path to a region with PathToRegion() appears more reliable.
You might use GetGdiPathRgn() for that purpose.

Definition at line 660 of file GdiUtil.cpp.

◆ FreeGdiPathData()

void WINAPI FreeGdiPathData ( PGdiPathData pData )

FreeGdiPathData() disposes path data retrieved by GetGdiPathData().

Definition at line 707 of file GdiUtil.cpp.

◆ GetGdiPathBounds()

bool WINAPI GetGdiPathBounds	(	HDC	hdc,
		PRECT	pBounds
	)

GetGdiPathBounds() computes the bounding rect for the current HDC path.

Definition at line 714 of file GdiUtil.cpp.

◆ GetGdiPathRgn()

HRGN WINAPI GetGdiPathRgn	(	HDC	hdc,
		OUT RGNDATA **	ppRgnData,
		OPTOUT RECT **	ppRgnRects
	)

GetGdiPathRgn() converts the current HDC path to a region and retrieves the region data.
After conversion, GDI clears the path from the display context.
The region can be used to perform operations not available for paths.
Call FreeRegionData() when done.

Parameters

hdc	Display context containing a closed path.
ppRgnData	Pointer to a RGNDATA pointer that recieves the region data.
ppRgnRects	Pointer to a RECT pointer that recieves the array of rects.

Transforming a path with ExtCreateRegion.: RGNDATA* rgnData;
HRGN pathRgn = GetGdiPathRgn( hdc, &rgnData, NULL );
XFORM xfm; memset( &xfm, 0, sizeof(XFORM) );
xfm.eM11 = 1.0f; // Horz scale
xfm.eM21 = -1.0f; // Horz shear
xfm.eM22 = 0.9f; // Vert scale
DWORD cbRgnData = rgnData->rdh.dwSize + rgnData->rdh.nRgnSize;
HRGN xfmRgn = ExtCreateRegion( &xfm, cbRgnData, rgnData );

Definition at line 728 of file GdiUtil.cpp.

◆ OffsetPoints()

void OffsetPoints	(	POINT *	Pts,
		UINT	nPts,
		int	dx,
		int	dy
	)

OffsetPoints() offsets an array of points by dx/dy.
Useful e.g to modify data from GetGdiPathData().

Definition at line 758 of file GdiUtil.cpp.

◆ OffsetRgnData()

void OffsetRgnData	(	PRGNDATA	prd,
		int	dx,
		int	dy
	)

OffsetRgnData() offsets the retrieved region data by dx/dy.
Useful e.g to modify data from GetGdiPathRgn() in lieu of ExtCreateRegion().

Definition at line 770 of file GdiUtil.cpp.

◆ SetIdentityMat2()

void SetIdentityMat2 ( MAT2 * pm )

SetIdentityMat2() initializes a MAT2 to the identity matrix (i.e. no transform).
An initialized MAT2 is a mandatory parameter for GetGlyphOutline(),
but is somewhat of a PITA to initialize as there's no FIXED support.
(If you need to manipulate FIXED, have a look ar Fixed.hpp.)

Definition at line 782 of file GdiUtil.cpp.