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FreeType » Docs » Controlling FreeType Modules » Parameter Tags

# Parameter Tags

## Synopsis

This section contains macros for the `FT_Parameter` structure that are used with various functions to activate some special functionality or different behaviour of various components of FreeType.

## FT_PARAM_TAG_IGNORE_TYPOGRAPHIC_FAMILY

    #define FT_PARAM_TAG_IGNORE_TYPOGRAPHIC_FAMILY \
              FT_MAKE_TAG( 'i', 'g', 'p', 'f' )

      /* this constant is deprecated */
    #define FT_PARAM_TAG_IGNORE_PREFERRED_FAMILY \
              FT_PARAM_TAG_IGNORE_TYPOGRAPHIC_FAMILY

A tag for `FT_Parameter` to make `FT_Open_Face` ignore typographic family names in the ‘name’ table (introduced in OpenType version 1.4). Use this for backward compatibility with legacy systems that have a four-faces-per-family restriction.

#### since

2.8

## FT_PARAM_TAG_IGNORE_TYPOGRAPHIC_SUBFAMILY

    #define FT_PARAM_TAG_IGNORE_TYPOGRAPHIC_SUBFAMILY \
              FT_MAKE_TAG( 'i', 'g', 'p', 's' )

      /* this constant is deprecated */
    #define FT_PARAM_TAG_IGNORE_PREFERRED_SUBFAMILY \
              FT_PARAM_TAG_IGNORE_TYPOGRAPHIC_SUBFAMILY

A tag for `FT_Parameter` to make `FT_Open_Face` ignore typographic subfamily names in the ‘name’ table (introduced in OpenType version 1.4). Use this for backward compatibility with legacy systems that have a four-faces-per-family restriction.

#### since

2.8

## FT_PARAM_TAG_INCREMENTAL

    #define FT_PARAM_TAG_INCREMENTAL \
              FT_MAKE_TAG( 'i', 'n', 'c', 'r' )

An `FT_Parameter` tag to be used with `FT_Open_Face` to indicate incremental glyph loading.

## FT_PARAM_TAG_LCD_FILTER_WEIGHTS

    #define FT_PARAM_TAG_LCD_FILTER_WEIGHTS \
              FT_MAKE_TAG( 'l', 'c', 'd', 'f' )

An `FT_Parameter` tag to be used with `FT_Face_Properties`. The corresponding argument specifies the five LCD filter weights for a given face (if using `FT_LOAD_TARGET_LCD`, for example), overriding the global default values or the values set up with `FT_Library_SetLcdFilterWeights`.

#### since

2.8

## FT_PARAM_TAG_RANDOM_SEED

    #define FT_PARAM_TAG_RANDOM_SEED \
              FT_MAKE_TAG( 's', 'e', 'e', 'd' )

An `FT_Parameter` tag to be used with `FT_Face_Properties`. The corresponding 32bit signed integer argument overrides the font driver's random seed value with a face-specific one; see `random-seed`.

#### since

2.8

## FT_PARAM_TAG_STEM_DARKENING

    #define FT_PARAM_TAG_STEM_DARKENING \
              FT_MAKE_TAG( 'd', 'a', 'r', 'k' )

An `FT_Parameter` tag to be used with `FT_Face_Properties`. The corresponding Boolean argument specifies whether to apply stem darkening, overriding the global default values or the values set up with `FT_Property_Set` (see `no-stem-darkening`).

This is a passive setting that only takes effect if the font driver or autohinter honors it, which the CFF, Type 1, and CID drivers always do, but the autohinter only in ‘light’ hinting mode (as of version 2.9).

#### since

2.8

## FT_PARAM_TAG_UNPATENTED_HINTING

    #define FT_PARAM_TAG_UNPATENTED_HINTING \
              FT_MAKE_TAG( 'u', 'n', 'p', 'a' )

Deprecated, no effect.

Previously: A constant used as the tag of an `FT_Parameter` structure to indicate that unpatented methods only should be used by the TrueType bytecode interpreter for a typeface opened by `FT_Open_Face`.