FD_DEVICEMETRICS structure (winddi.h)

Article
09/01/2022

The FD_DEVICEMETRICS structure is used to provide device-specific font information to GDI if the iMode parameter of the driver-supplied DrvQueryFontData function is QFD_MAXEXTENTS.

Syntax

typedef struct _FD_DEVICEMETRICS {
  FLONG    flRealizedType;
  POINTE   pteBase;
  POINTE   pteSide;
  LONG     lD;
  FIX      fxMaxAscender;
  FIX      fxMaxDescender;
  POINTL   ptlUnderline1;
  POINTL   ptlStrikeOut;
  POINTL   ptlULThickness;
  POINTL   ptlSOThickness;
  ULONG    cxMax;
  ULONG    cyMax;
  ULONG    cjGlyphMax;
  FD_XFORM fdxQuantized;
  LONG     lNonLinearExtLeading;
  LONG     lNonLinearIntLeading;
  LONG     lNonLinearMaxCharWidth;
  LONG     lNonLinearAvgCharWidth;
  LONG     lMinA;
  LONG     lMinC;
  LONG     lMinD;
  LONG     alReserved[1];
} FD_DEVICEMETRICS, *PFD_DEVICEMETRICS;

Members

flRealizedType

Is a set of accelerator flags. This value can be a combination of the following values:

FDM_TYPE_BM_SIDE_CONST

An accelerator for horizontal and vertical writing. If this flag is set, the font has constant height for all bitmaps. In the horizontal case, this means that the cy dimension is constant; in the vertical case, this means that the cx dimension is constant. This accelerator is not used for outlines.

FDM_TYPE_CHAR_INC_EQUAL_BM_BASE

An accelerator for horizontal and vertical writing. In the horizontal case, if this flag is set, each glyph's advance width is equal to the cx dimension of the glyph bitmap; in the vertical case, if this flag is set, each glyph's advance width is equal to the cy dimension of the glyph bitmap. This accelerator is not used for outlines.

FDM_TYPE_CONST_BEARINGS

If set, the a and c spacing is constant for all glyphs.

FDM_TYPE_MAXEXT_EQUAL_BM_SIDE

This flag can be set only if FDM_TYPE_BM_SIDE_CONST is also set. If set, the font height (as defined above for horizontal and vertical writing) is equal to the sum of max ascender and max descender. This accelerator is not used for outlines.

FDM_TYPE_ZERO_BEARINGS

If set, the a and c spacing is zero for all glyphs.

pteBase

Specifies a POINTE structure that contains the notional space unit vector along the font's baseline, transformed to device space and then normalized. For more information, see POINTE in GDI Data Types.

pteSide

Specifies POINTE structure that contains a notional space unit vector perpendicular to the font's baseline in the direction of the ascender, transformed to device space and then normalized. In notional space, baseline and ascender directions must be orthogonal, but in device space, pteBase and pteSide do not have to be orthogonal, depending on the Notional to Device space transform.

lD

Specifies the advance width if the font is a fixed pitch (monospaced) font. If the font is a variable pitch font, this member should be set to zero.

fxMaxAscender

Specifies the hinted maximum ascender height for this font instance, measured along pteSide. See the FIX data type in GDI Data Types.

fxMaxDescender

Specifies the hinted maximum descender height for this font instance, measured along pteSide. See the FIX data type in GDI Data Types.

ptlUnderline1

Specifies a POINTL structure that contains the hinted underline position for this font instance, relative to the glyph's character origin.

ptlStrikeOut

Specifies a POINTL structure that contains the hinted strikeout position for this font instance, relative to the glyph's character origin.

ptlULThickness

Specifies a POINTL structure that contains the hinted underline thickness for this font instance. This vector defines the side of the rectangle used to draw the underline. The base is implicitly defined by the baseline.

ptlSOThickness

Specifies a POINTL structure that contains the hinted strikeout thickness for this font instance. This vector defines the side of the rectangle used to draw the strikeout. The base is implicitly defined by the baseline.

cxMax

Specifies the hinted maximum glyph bitmap width, in pixels, for this font instance. Not used for outlines.

cyMax

Specifies the hinted maximum glyph bitmap height, in pixels, for this font instance. Not used for outlines.

cjGlyphMax

Specifies the hinted maximum size of a glyph, in bytes, for this font instance. This value is the maximum size of the GLYPHBITS structure needed to store any of the font's glyphs.

fdxQuantized

Specifies an FD_XFORM structure. The font driver fills in the font transformation that is actually used in the realization of the font. This may differ from the transformation requested by GDI as defined by FONTOBJ_pxoGetXform.

lNonLinearExtLeading

Is the nonlinear external leading in 28.4 device units.

lNonLinearIntLeading

Is the nonlinear internal leading in 28.4 device units.

lNonLinearMaxCharWidth

Is the nonlinear maximum character increment in 28.4 device units.

lNonLinearAvgCharWidth

Is the nonlinear average character width in 28.4 device units.

lMinA

Is the largest negative A space for this font realization, specified as an absolute value.

lMinC

Is the largest negative C space for this font realization, specified as an absolute value.

lMinD

Is the smallest nonzero character width for this font realization.

alReserved[1]

Is reserved and should be ignored by the font provider.

Requirements

Requirement	Value
Header	winddi.h (include Winddi.h)