ref: 71f661804e88db5b12cc1a143e03ef53b5eab894
dir: /include/freetype/ftmm.h/
/***************************************************************************/
/* */
/* ftmm.h */
/* */
/* FreeType Multiple Master font interface (specification). */
/* */
/* Copyright 1996-2017 by */
/* David Turner, Robert Wilhelm, and Werner Lemberg. */
/* */
/* This file is part of the FreeType project, and may only be used, */
/* modified, and distributed under the terms of the FreeType project */
/* license, LICENSE.TXT. By continuing to use, modify, or distribute */
/* this file you indicate that you have read the license and */
/* understand and accept it fully. */
/* */
/***************************************************************************/
#ifndef FTMM_H_
#define FTMM_H_
#include <ft2build.h>
#include FT_TYPE1_TABLES_H
FT_BEGIN_HEADER
/*************************************************************************/
/* */
/* <Section> */
/* multiple_masters */
/* */
/* <Title> */
/* Multiple Masters */
/* */
/* <Abstract> */
/* How to manage Multiple Masters fonts. */
/* */
/* <Description> */
/* The following types and functions are used to manage Multiple */
/* Master fonts, i.e., the selection of specific design instances by */
/* setting design axis coordinates. */
/* */
/* Besides Adobe MM fonts, the interface supports Apple's TrueType GX */
/* and OpenType variation fonts. Some of the routines only work with */
/* Adobe MM fonts, others will work with all three types. They are */
/* similar enough that a consistent interface makes sense. */
/* */
/*************************************************************************/
/*************************************************************************/
/* */
/* <Struct> */
/* FT_MM_Axis */
/* */
/* <Description> */
/* A structure to model a given axis in design space for Multiple */
/* Masters fonts. */
/* */
/* This structure can't be used for TrueType GX or OpenType variation */
/* fonts. */
/* */
/* <Fields> */
/* name :: The axis's name. */
/* */
/* minimum :: The axis's minimum design coordinate. */
/* */
/* maximum :: The axis's maximum design coordinate. */
/* */
typedef struct FT_MM_Axis_
{
FT_String* name;
FT_Long minimum;
FT_Long maximum;
} FT_MM_Axis;
/*************************************************************************/
/* */
/* <Struct> */
/* FT_Multi_Master */
/* */
/* <Description> */
/* A structure to model the axes and space of a Multiple Masters */
/* font. */
/* */
/* This structure can't be used for TrueType GX or OpenType variation */
/* fonts. */
/* */
/* <Fields> */
/* num_axis :: Number of axes. Cannot exceed~4. */
/* */
/* num_designs :: Number of designs; should be normally 2^num_axis */
/* even though the Type~1 specification strangely */
/* allows for intermediate designs to be present. */
/* This number cannot exceed~16. */
/* */
/* axis :: A table of axis descriptors. */
/* */
typedef struct FT_Multi_Master_
{
FT_UInt num_axis;
FT_UInt num_designs;
FT_MM_Axis axis[T1_MAX_MM_AXIS];
} FT_Multi_Master;
/*************************************************************************/
/* */
/* <Struct> */
/* FT_Var_Axis */
/* */
/* <Description> */
/* A structure to model a given axis in design space for Multiple */
/* Masters, TrueType GX, and OpenType variation fonts. */
/* */
/* <Fields> */
/* name :: The axis's name. */
/* Not always meaningful for TrueType GX or OpenType */
/* variation fonts. */
/* */
/* minimum :: The axis's minimum design coordinate. */
/* */
/* def :: The axis's default design coordinate. */
/* FreeType computes meaningful default values for Adobe */
/* MM fonts. */
/* */
/* maximum :: The axis's maximum design coordinate. */
/* */
/* tag :: The axis's tag (the equivalent to `name' for TrueType */
/* GX and OpenType variation fonts). FreeType provides */
/* default values for Adobe MM fonts if possible. */
/* */
/* strid :: The axis name entry in the font's `name' table. This */
/* is another (and often better) version of the `name' */
/* field for TrueType GX or OpenType variation fonts. Not */
/* meaningful for Adobe MM fonts. */
/* */
/* <Note> */
/* The fields `minimum', `def', and `maximum' are 16.16 fractional */
/* values for TrueType GX and OpenType variation fonts. For Adobe MM */
/* fonts, the values are integers. */
/* */
typedef struct FT_Var_Axis_
{
FT_String* name;
FT_Fixed minimum;
FT_Fixed def;
FT_Fixed maximum;
FT_ULong tag;
FT_UInt strid;
} FT_Var_Axis;
/*************************************************************************/
/* */
/* <Struct> */
/* FT_Var_Named_Style */
/* */
/* <Description> */
/* A structure to model a named instance in a TrueType GX or OpenType */
/* variation font. */
/* */
/* This structure can't be used for Adobe MM fonts. */
/* */
/* <Fields> */
/* coords :: The design coordinates for this instance. */
/* This is an array with one entry for each axis. */
/* */
/* strid :: The entry in `name' table identifying this instance. */
/* */
/* psid :: The entry in `name' table identifying a PostScript name */
/* for this instance. Value 0xFFFF indicates a missing */
/* entry. */
/* */
typedef struct FT_Var_Named_Style_
{
FT_Fixed* coords;
FT_UInt strid;
FT_UInt psid; /* since 2.7.1 */
} FT_Var_Named_Style;
/*************************************************************************/
/* */
/* <Struct> */
/* FT_MM_Var */
/* */
/* <Description> */
/* A structure to model the axes and space of an Adobe MM, TrueType */
/* GX, or OpenType variation font. */
/* */
/* Some fields are specific to one format and not to the others. */
/* */
/* <Fields> */
/* num_axis :: The number of axes. The maximum value is~4 for */
/* Adobe MM fonts; no limit in TrueType GX or */
/* OpenType variation fonts. */
/* */
/* num_designs :: The number of designs; should be normally */
/* 2^num_axis for Adobe MM fonts. Not meaningful */
/* for TrueType GX or OpenType variation fonts */
/* (where every glyph could have a different */
/* number of designs). */
/* */
/* num_namedstyles :: The number of named styles; a `named style' is */
/* a tuple of design coordinates that has a string */
/* ID (in the `name' table) associated with it. */
/* The font can tell the user that, for example, */
/* [Weight=1.5,Width=1.1] is `Bold'. Another name */
/* for `named style' is `named instance'. */
/* */
/* For Adobe Multiple Masters fonts, this value is */
/* always zero because the format does not support */
/* named styles. */
/* */
/* axis :: An axis descriptor table. */
/* TrueType GX and OpenType variation fonts */
/* contain slightly more data than Adobe MM fonts. */
/* Memory management of this pointer is done */
/* internally by FreeType. */
/* */
/* namedstyle :: A named style (instance) table. */
/* Only meaningful for TrueType GX and OpenType */
/* variation fonts. Memory management of this */
/* pointer is done internally by FreeType. */
/* */
typedef struct FT_MM_Var_
{
FT_UInt num_axis;
FT_UInt num_designs;
FT_UInt num_namedstyles;
FT_Var_Axis* axis;
FT_Var_Named_Style* namedstyle;
} FT_MM_Var;
/*************************************************************************/
/* */
/* <Function> */
/* FT_Get_Multi_Master */
/* */
/* <Description> */
/* Retrieve a variation descriptor of a given Adobe MM font. */
/* */
/* This function can't be used with TrueType GX or OpenType variation */
/* fonts. */
/* */
/* <Input> */
/* face :: A handle to the source face. */
/* */
/* <Output> */
/* amaster :: The Multiple Masters descriptor. */
/* */
/* <Return> */
/* FreeType error code. 0~means success. */
/* */
FT_EXPORT( FT_Error )
FT_Get_Multi_Master( FT_Face face,
FT_Multi_Master *amaster );
/*************************************************************************/
/* */
/* <Function> */
/* FT_Get_MM_Var */
/* */
/* <Description> */
/* Retrieve a variation descriptor for a given font. */
/* */
/* This function works with all supported variation formats. */
/* */
/* <Input> */
/* face :: A handle to the source face. */
/* */
/* <Output> */
/* amaster :: The variation descriptor. */
/* Allocates a data structure, which the user must */
/* deallocate with `free' after use. */
/* */
/* <Return> */
/* FreeType error code. 0~means success. */
/* */
FT_EXPORT( FT_Error )
FT_Get_MM_Var( FT_Face face,
FT_MM_Var* *amaster );
/*************************************************************************/
/* */
/* <Function> */
/* FT_Set_MM_Design_Coordinates */
/* */
/* <Description> */
/* For Adobe MM fonts, choose an interpolated font design through */
/* design coordinates. */
/* */
/* This function can't be used with TrueType GX or OpenType variation */
/* fonts. */
/* */
/* <InOut> */
/* face :: A handle to the source face. */
/* */
/* <Input> */
/* num_coords :: The number of available design coordinates. If it */
/* is larger than the number of axes, ignore the excess */
/* values. If it is smaller than the number of axes, */
/* use default values for the remaining axes. */
/* */
/* coords :: An array of design coordinates. */
/* */
/* <Return> */
/* FreeType error code. 0~means success. */
/* */
/* <Note> */
/* To reset all axes to the default values, call the function with */
/* `num_coords' set to zero and `coords' set to NULL (new feature in */
/* FreeType version 2.8.1). */
/* */
FT_EXPORT( FT_Error )
FT_Set_MM_Design_Coordinates( FT_Face face,
FT_UInt num_coords,
FT_Long* coords );
/*************************************************************************/
/* */
/* <Function> */
/* FT_Set_Var_Design_Coordinates */
/* */
/* <Description> */
/* Choose an interpolated font design through design coordinates. */
/* */
/* This function works with all supported variation formats. */
/* */
/* <InOut> */
/* face :: A handle to the source face. */
/* */
/* <Input> */
/* num_coords :: The number of available design coordinates. If it */
/* is larger than the number of axes, ignore the excess */
/* values. If it is smaller than the number of axes, */
/* use default values for the remaining axes. */
/* */
/* coords :: An array of design coordinates. */
/* */
/* <Return> */
/* FreeType error code. 0~means success. */
/* */
/* <Note> */
/* To reset all axes to the default values, call the function with */
/* `num_coords' set to zero and `coords' set to NULL (new feature in */
/* FreeType version 2.8.1). */
/* */
FT_EXPORT( FT_Error )
FT_Set_Var_Design_Coordinates( FT_Face face,
FT_UInt num_coords,
FT_Fixed* coords );
/*************************************************************************/
/* */
/* <Function> */
/* FT_Get_Var_Design_Coordinates */
/* */
/* <Description> */
/* Get the design coordinates of the currently selected interpolated */
/* font. */
/* */
/* This function works with all supported variation formats. */
/* */
/* <Input> */
/* face :: A handle to the source face. */
/* */
/* num_coords :: The number of design coordinates to retrieve. If it */
/* is larger than the number of axes, set the excess */
/* values to~0. */
/* */
/* <Output> */
/* coords :: The design coordinates array. */
/* */
/* <Return> */
/* FreeType error code. 0~means success. */
/* */
FT_EXPORT( FT_Error )
FT_Get_Var_Design_Coordinates( FT_Face face,
FT_UInt num_coords,
FT_Fixed* coords );
/*************************************************************************/
/* */
/* <Function> */
/* FT_Set_MM_Blend_Coordinates */
/* */
/* <Description> */
/* Choose an interpolated font design through normalized blend */
/* coordinates. */
/* */
/* This function works with all supported variation formats. */
/* */
/* <InOut> */
/* face :: A handle to the source face. */
/* */
/* <Input> */
/* num_coords :: The number of available design coordinates. If it */
/* is larger than the number of axes, ignore the excess */
/* values. If it is smaller than the number of axes, */
/* use default values for the remaining axes. */
/* */
/* coords :: The design coordinates array (each element must be */
/* between 0 and 1.0 for Adobe MM fonts, and between */
/* -1.0 and 1.0 for TrueType GX and OpenType variation */
/* fonts). */
/* */
/* <Return> */
/* FreeType error code. 0~means success. */
/* */
/* <Note> */
/* To reset all axes to the default values, call the function with */
/* `num_coords' set to zero and `coords' set to NULL (new feature in */
/* FreeType version 2.8.1). */
/* */
FT_EXPORT( FT_Error )
FT_Set_MM_Blend_Coordinates( FT_Face face,
FT_UInt num_coords,
FT_Fixed* coords );
/*************************************************************************/
/* */
/* <Function> */
/* FT_Get_MM_Blend_Coordinates */
/* */
/* <Description> */
/* Get the normalized blend coordinates of the currently selected */
/* interpolated font. */
/* */
/* This function works with all supported variation formats. */
/* */
/* <Input> */
/* face :: A handle to the source face. */
/* */
/* num_coords :: The number of normalized blend coordinates to */
/* retrieve. If it is larger than the number of axes, */
/* set the excess values to~0.5 for Adobe MM fonts, and */
/* to~0 for TrueType GX and OpenType variation fonts. */
/* */
/* <Output> */
/* coords :: The normalized blend coordinates array. */
/* */
/* <Return> */
/* FreeType error code. 0~means success. */
/* */
FT_EXPORT( FT_Error )
FT_Get_MM_Blend_Coordinates( FT_Face face,
FT_UInt num_coords,
FT_Fixed* coords );
/*************************************************************************/
/* */
/* <Function> */
/* FT_Set_Var_Blend_Coordinates */
/* */
/* <Description> */
/* This is another name of @FT_Set_MM_Blend_Coordinates. */
/* */
FT_EXPORT( FT_Error )
FT_Set_Var_Blend_Coordinates( FT_Face face,
FT_UInt num_coords,
FT_Fixed* coords );
/*************************************************************************/
/* */
/* <Function> */
/* FT_Get_Var_Blend_Coordinates */
/* */
/* <Description> */
/* This is another name of @FT_Get_MM_Blend_Coordinates. */
/* */
FT_EXPORT( FT_Error )
FT_Get_Var_Blend_Coordinates( FT_Face face,
FT_UInt num_coords,
FT_Fixed* coords );
/*************************************************************************/
/* */
/* <Enum> */
/* FT_VAR_AXIS_FLAG_XXX */
/* */
/* <Description> */
/* A list of bit flags used in the return value of */
/* @FT_Get_Var_Axis_Flags. */
/* */
/* <Values> */
/* FT_VAR_AXIS_FLAG_HIDDEN :: */
/* The variation axis should not be exposed to user interfaces. */
/* */
#define FT_VAR_AXIS_FLAG_HIDDEN 1
/*************************************************************************/
/* */
/* <Function> */
/* FT_Get_Var_Axis_Flags */
/* */
/* <Description> */
/* Get the `flags' field of an OpenType Variation Axis Record. */
/* */
/* Not meaningful for Adobe MM fonts (`*flags' is always zero). */
/* */
/* <Input> */
/* master :: The variation descriptor. */
/* */
/* axis_index :: The index of the requested variation axis. */
/* */
/* <Output> */
/* flags :: The `flags' field. See @FT_VAR_AXIS_FLAG_XXX for */
/* possible values. */
/* */
/* <Return> */
/* FreeType error code. 0~means success. */
/* */
FT_EXPORT( FT_Error )
FT_Get_Var_Axis_Flags( FT_MM_Var* master,
FT_UInt axis_index,
FT_UInt* flags );
/* */
FT_END_HEADER
#endif /* FTMM_H_ */
/* END */