FT_GASP_XXX

Defined in FT_GASP_H (freetype/ftgasp.h).

#define FT_GASP_NO_TABLE               -1
#define FT_GASP_DO_GRIDFIT           0x01
#define FT_GASP_DO_GRAY              0x02
#define FT_GASP_SYMMETRIC_GRIDFIT    0x04
#define FT_GASP_SYMMETRIC_SMOOTHING  0x08

A list of values and/or bit-flags returned by the FT_Get_Gasp function.

values

FT_GASP_NO_TABLE	This special value means that there is no GASP table in this face. It is up to the client to decide what to do.
FT_GASP_DO_GRIDFIT	Grid-fitting and hinting should be performed at the specified ppem. This really means TrueType bytecode interpretation. If this bit is not set, no hinting gets applied.
FT_GASP_DO_GRAY	Anti-aliased rendering should be performed at the specified ppem. If not set, do monochrome rendering.
FT_GASP_SYMMETRIC_SMOOTHING	If set, smoothing along multiple axes must be used with ClearType.
FT_GASP_SYMMETRIC_GRIDFIT	Grid-fitting must be used with ClearType's symmetric smoothing.

note

The bit-flags ‘FT_GASP_DO_GRIDFIT’ and ‘FT_GASP_DO_GRAY’ are to be used for standard font rasterization only. Independently of that, ‘FT_GASP_SYMMETRIC_SMOOTHING’ and ‘FT_GASP_SYMMETRIC_GRIDFIT’ are to be used if ClearType is enabled (and ‘FT_GASP_DO_GRIDFIT’ and ‘FT_GASP_DO_GRAY’ are consequently ignored).

‘ClearType’ is Microsoft's implementation of LCD rendering, partly protected by patents.

since

2.3.0

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FT_Get_Gasp

Defined in FT_GASP_H (freetype/ftgasp.h).

  FT_EXPORT( FT_Int )
  FT_Get_Gasp( FT_Face  face,
               FT_UInt  ppem );

For a TrueType or OpenType font file, return the rasterizer behaviour flags from the font's ‘gasp’ table corresponding to a given character pixel size.

input

face	The source face handle.
ppem	The vertical character pixel size.

return

Bit flags (see FT_GASP_XXX), or FT_GASP_NO_TABLE if there is no ‘gasp’ table in the face.

note

If you want to use the MM functionality of OpenType variation fonts (i.e., using FT_Set_Var_Design_Coordinates and friends), call this function after setting an instance since the return values can change.

since

2.3.0

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