/***************************************************************************/ | |
/* */ | |
/* ftglyph.h */ | |
/* */ | |
/* FreeType convenience functions to handle glyphs (specification). */ | |
/* */ | |
/* Copyright 1996-2015 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. */ | |
/* */ | |
/***************************************************************************/ | |
/*************************************************************************/ | |
/* */ | |
/* This file contains the definition of several convenience functions */ | |
/* that can be used by client applications to easily retrieve glyph */ | |
/* bitmaps and outlines from a given face. */ | |
/* */ | |
/* These functions should be optional if you are writing a font server */ | |
/* or text layout engine on top of FreeType. However, they are pretty */ | |
/* handy for many other simple uses of the library. */ | |
/* */ | |
/*************************************************************************/ | |
#ifndef __FTGLYPH_H__ | |
#define __FTGLYPH_H__ | |
#include <ft2build.h> | |
#include FT_FREETYPE_H | |
#ifdef FREETYPE_H | |
#error "freetype.h of FreeType 1 has been loaded!" | |
#error "Please fix the directory search order for header files" | |
#error "so that freetype.h of FreeType 2 is found first." | |
#endif | |
FT_BEGIN_HEADER | |
/*************************************************************************/ | |
/* */ | |
/* <Section> */ | |
/* glyph_management */ | |
/* */ | |
/* <Title> */ | |
/* Glyph Management */ | |
/* */ | |
/* <Abstract> */ | |
/* Generic interface to manage individual glyph data. */ | |
/* */ | |
/* <Description> */ | |
/* This section contains definitions used to manage glyph data */ | |
/* through generic FT_Glyph objects. Each of them can contain a */ | |
/* bitmap, a vector outline, or even images in other formats. */ | |
/* */ | |
/*************************************************************************/ | |
/* forward declaration to a private type */ | |
typedef struct FT_Glyph_Class_ FT_Glyph_Class; | |
/*************************************************************************/ | |
/* */ | |
/* <Type> */ | |
/* FT_Glyph */ | |
/* */ | |
/* <Description> */ | |
/* Handle to an object used to model generic glyph images. It is a */ | |
/* pointer to the @FT_GlyphRec structure and can contain a glyph */ | |
/* bitmap or pointer. */ | |
/* */ | |
/* <Note> */ | |
/* Glyph objects are not owned by the library. You must thus release */ | |
/* them manually (through @FT_Done_Glyph) _before_ calling */ | |
/* @FT_Done_FreeType. */ | |
/* */ | |
typedef struct FT_GlyphRec_* FT_Glyph; | |
/*************************************************************************/ | |
/* */ | |
/* <Struct> */ | |
/* FT_GlyphRec */ | |
/* */ | |
/* <Description> */ | |
/* The root glyph structure contains a given glyph image plus its */ | |
/* advance width in 16.16 fixed-point format. */ | |
/* */ | |
/* <Fields> */ | |
/* library :: A handle to the FreeType library object. */ | |
/* */ | |
/* clazz :: A pointer to the glyph's class. Private. */ | |
/* */ | |
/* format :: The format of the glyph's image. */ | |
/* */ | |
/* advance :: A 16.16 vector that gives the glyph's advance width. */ | |
/* */ | |
typedef struct FT_GlyphRec_ | |
{ | |
FT_Library library; | |
const FT_Glyph_Class* clazz; | |
FT_Glyph_Format format; | |
FT_Vector advance; | |
} FT_GlyphRec; | |
/*************************************************************************/ | |
/* */ | |
/* <Type> */ | |
/* FT_BitmapGlyph */ | |
/* */ | |
/* <Description> */ | |
/* A handle to an object used to model a bitmap glyph image. This is */ | |
/* a sub-class of @FT_Glyph, and a pointer to @FT_BitmapGlyphRec. */ | |
/* */ | |
typedef struct FT_BitmapGlyphRec_* FT_BitmapGlyph; | |
/*************************************************************************/ | |
/* */ | |
/* <Struct> */ | |
/* FT_BitmapGlyphRec */ | |
/* */ | |
/* <Description> */ | |
/* A structure used for bitmap glyph images. This really is a */ | |
/* `sub-class' of @FT_GlyphRec. */ | |
/* */ | |
/* <Fields> */ | |
/* root :: The root @FT_Glyph fields. */ | |
/* */ | |
/* left :: The left-side bearing, i.e., the horizontal distance */ | |
/* from the current pen position to the left border of the */ | |
/* glyph bitmap. */ | |
/* */ | |
/* top :: The top-side bearing, i.e., the vertical distance from */ | |
/* the current pen position to the top border of the glyph */ | |
/* bitmap. This distance is positive for upwards~y! */ | |
/* */ | |
/* bitmap :: A descriptor for the bitmap. */ | |
/* */ | |
/* <Note> */ | |
/* You can typecast an @FT_Glyph to @FT_BitmapGlyph if you have */ | |
/* `glyph->format == FT_GLYPH_FORMAT_BITMAP'. This lets you access */ | |
/* the bitmap's contents easily. */ | |
/* */ | |
/* The corresponding pixel buffer is always owned by @FT_BitmapGlyph */ | |
/* and is thus created and destroyed with it. */ | |
/* */ | |
typedef struct FT_BitmapGlyphRec_ | |
{ | |
FT_GlyphRec root; | |
FT_Int left; | |
FT_Int top; | |
FT_Bitmap bitmap; | |
} FT_BitmapGlyphRec; | |
/*************************************************************************/ | |
/* */ | |
/* <Type> */ | |
/* FT_OutlineGlyph */ | |
/* */ | |
/* <Description> */ | |
/* A handle to an object used to model an outline glyph image. This */ | |
/* is a sub-class of @FT_Glyph, and a pointer to @FT_OutlineGlyphRec. */ | |
/* */ | |
typedef struct FT_OutlineGlyphRec_* FT_OutlineGlyph; | |
/*************************************************************************/ | |
/* */ | |
/* <Struct> */ | |
/* FT_OutlineGlyphRec */ | |
/* */ | |
/* <Description> */ | |
/* A structure used for outline (vectorial) glyph images. This */ | |
/* really is a `sub-class' of @FT_GlyphRec. */ | |
/* */ | |
/* <Fields> */ | |
/* root :: The root @FT_Glyph fields. */ | |
/* */ | |
/* outline :: A descriptor for the outline. */ | |
/* */ | |
/* <Note> */ | |
/* You can typecast an @FT_Glyph to @FT_OutlineGlyph if you have */ | |
/* `glyph->format == FT_GLYPH_FORMAT_OUTLINE'. This lets you access */ | |
/* the outline's content easily. */ | |
/* */ | |
/* As the outline is extracted from a glyph slot, its coordinates are */ | |
/* expressed normally in 26.6 pixels, unless the flag */ | |
/* @FT_LOAD_NO_SCALE was used in @FT_Load_Glyph() or @FT_Load_Char(). */ | |
/* */ | |
/* The outline's tables are always owned by the object and are */ | |
/* destroyed with it. */ | |
/* */ | |
typedef struct FT_OutlineGlyphRec_ | |
{ | |
FT_GlyphRec root; | |
FT_Outline outline; | |
} FT_OutlineGlyphRec; | |
/*************************************************************************/ | |
/* */ | |
/* <Function> */ | |
/* FT_Get_Glyph */ | |
/* */ | |
/* <Description> */ | |
/* A function used to extract a glyph image from a slot. Note that */ | |
/* the created @FT_Glyph object must be released with @FT_Done_Glyph. */ | |
/* */ | |
/* <Input> */ | |
/* slot :: A handle to the source glyph slot. */ | |
/* */ | |
/* <Output> */ | |
/* aglyph :: A handle to the glyph object. */ | |
/* */ | |
/* <Return> */ | |
/* FreeType error code. 0~means success. */ | |
/* */ | |
FT_EXPORT( FT_Error ) | |
FT_Get_Glyph( FT_GlyphSlot slot, | |
FT_Glyph *aglyph ); | |
/*************************************************************************/ | |
/* */ | |
/* <Function> */ | |
/* FT_Glyph_Copy */ | |
/* */ | |
/* <Description> */ | |
/* A function used to copy a glyph image. Note that the created */ | |
/* @FT_Glyph object must be released with @FT_Done_Glyph. */ | |
/* */ | |
/* <Input> */ | |
/* source :: A handle to the source glyph object. */ | |
/* */ | |
/* <Output> */ | |
/* target :: A handle to the target glyph object. 0~in case of */ | |
/* error. */ | |
/* */ | |
/* <Return> */ | |
/* FreeType error code. 0~means success. */ | |
/* */ | |
FT_EXPORT( FT_Error ) | |
FT_Glyph_Copy( FT_Glyph source, | |
FT_Glyph *target ); | |
/*************************************************************************/ | |
/* */ | |
/* <Function> */ | |
/* FT_Glyph_Transform */ | |
/* */ | |
/* <Description> */ | |
/* Transform a glyph image if its format is scalable. */ | |
/* */ | |
/* <InOut> */ | |
/* glyph :: A handle to the target glyph object. */ | |
/* */ | |
/* <Input> */ | |
/* matrix :: A pointer to a 2x2 matrix to apply. */ | |
/* */ | |
/* delta :: A pointer to a 2d vector to apply. Coordinates are */ | |
/* expressed in 1/64th of a pixel. */ | |
/* */ | |
/* <Return> */ | |
/* FreeType error code (if not 0, the glyph format is not scalable). */ | |
/* */ | |
/* <Note> */ | |
/* The 2x2 transformation matrix is also applied to the glyph's */ | |
/* advance vector. */ | |
/* */ | |
FT_EXPORT( FT_Error ) | |
FT_Glyph_Transform( FT_Glyph glyph, | |
FT_Matrix* matrix, | |
FT_Vector* delta ); | |
/*************************************************************************/ | |
/* */ | |
/* <Enum> */ | |
/* FT_Glyph_BBox_Mode */ | |
/* */ | |
/* <Description> */ | |
/* The mode how the values of @FT_Glyph_Get_CBox are returned. */ | |
/* */ | |
/* <Values> */ | |
/* FT_GLYPH_BBOX_UNSCALED :: */ | |
/* Return unscaled font units. */ | |
/* */ | |
/* FT_GLYPH_BBOX_SUBPIXELS :: */ | |
/* Return unfitted 26.6 coordinates. */ | |
/* */ | |
/* FT_GLYPH_BBOX_GRIDFIT :: */ | |
/* Return grid-fitted 26.6 coordinates. */ | |
/* */ | |
/* FT_GLYPH_BBOX_TRUNCATE :: */ | |
/* Return coordinates in integer pixels. */ | |
/* */ | |
/* FT_GLYPH_BBOX_PIXELS :: */ | |
/* Return grid-fitted pixel coordinates. */ | |
/* */ | |
typedef enum FT_Glyph_BBox_Mode_ | |
{ | |
FT_GLYPH_BBOX_UNSCALED = 0, | |
FT_GLYPH_BBOX_SUBPIXELS = 0, | |
FT_GLYPH_BBOX_GRIDFIT = 1, | |
FT_GLYPH_BBOX_TRUNCATE = 2, | |
FT_GLYPH_BBOX_PIXELS = 3 | |
} FT_Glyph_BBox_Mode; | |
/* these constants are deprecated; use the corresponding */ | |
/* `FT_Glyph_BBox_Mode' values instead */ | |
#define ft_glyph_bbox_unscaled FT_GLYPH_BBOX_UNSCALED | |
#define ft_glyph_bbox_subpixels FT_GLYPH_BBOX_SUBPIXELS | |
#define ft_glyph_bbox_gridfit FT_GLYPH_BBOX_GRIDFIT | |
#define ft_glyph_bbox_truncate FT_GLYPH_BBOX_TRUNCATE | |
#define ft_glyph_bbox_pixels FT_GLYPH_BBOX_PIXELS | |
/*************************************************************************/ | |
/* */ | |
/* <Function> */ | |
/* FT_Glyph_Get_CBox */ | |
/* */ | |
/* <Description> */ | |
/* Return a glyph's `control box'. The control box encloses all the */ | |
/* outline's points, including Bézier control points. Though it */ | |
/* coincides with the exact bounding box for most glyphs, it can be */ | |
/* slightly larger in some situations (like when rotating an outline */ | |
/* that contains Bézier outside arcs). */ | |
/* */ | |
/* Computing the control box is very fast, while getting the bounding */ | |
/* box can take much more time as it needs to walk over all segments */ | |
/* and arcs in the outline. To get the latter, you can use the */ | |
/* `ftbbox' component, which is dedicated to this single task. */ | |
/* */ | |
/* <Input> */ | |
/* glyph :: A handle to the source glyph object. */ | |
/* */ | |
/* mode :: The mode that indicates how to interpret the returned */ | |
/* bounding box values. */ | |
/* */ | |
/* <Output> */ | |
/* acbox :: The glyph coordinate bounding box. Coordinates are */ | |
/* expressed in 1/64th of pixels if it is grid-fitted. */ | |
/* */ | |
/* <Note> */ | |
/* Coordinates are relative to the glyph origin, using the y~upwards */ | |
/* convention. */ | |
/* */ | |
/* If the glyph has been loaded with @FT_LOAD_NO_SCALE, `bbox_mode' */ | |
/* must be set to @FT_GLYPH_BBOX_UNSCALED to get unscaled font */ | |
/* units in 26.6 pixel format. The value @FT_GLYPH_BBOX_SUBPIXELS */ | |
/* is another name for this constant. */ | |
/* */ | |
/* If the font is tricky and the glyph has been loaded with */ | |
/* @FT_LOAD_NO_SCALE, the resulting CBox is meaningless. To get */ | |
/* reasonable values for the CBox it is necessary to load the glyph */ | |
/* at a large ppem value (so that the hinting instructions can */ | |
/* properly shift and scale the subglyphs), then extracting the CBox, */ | |
/* which can be eventually converted back to font units. */ | |
/* */ | |
/* Note that the maximum coordinates are exclusive, which means that */ | |
/* one can compute the width and height of the glyph image (be it in */ | |
/* integer or 26.6 pixels) as: */ | |
/* */ | |
/* { */ | |
/* width = bbox.xMax - bbox.xMin; */ | |
/* height = bbox.yMax - bbox.yMin; */ | |
/* } */ | |
/* */ | |
/* Note also that for 26.6 coordinates, if `bbox_mode' is set to */ | |
/* @FT_GLYPH_BBOX_GRIDFIT, the coordinates will also be grid-fitted, */ | |
/* which corresponds to: */ | |
/* */ | |
/* { */ | |
/* bbox.xMin = FLOOR(bbox.xMin); */ | |
/* bbox.yMin = FLOOR(bbox.yMin); */ | |
/* bbox.xMax = CEILING(bbox.xMax); */ | |
/* bbox.yMax = CEILING(bbox.yMax); */ | |
/* } */ | |
/* */ | |
/* To get the bbox in pixel coordinates, set `bbox_mode' to */ | |
/* @FT_GLYPH_BBOX_TRUNCATE. */ | |
/* */ | |
/* To get the bbox in grid-fitted pixel coordinates, set `bbox_mode' */ | |
/* to @FT_GLYPH_BBOX_PIXELS. */ | |
/* */ | |
FT_EXPORT( void ) | |
FT_Glyph_Get_CBox( FT_Glyph glyph, | |
FT_UInt bbox_mode, | |
FT_BBox *acbox ); | |
/*************************************************************************/ | |
/* */ | |
/* <Function> */ | |
/* FT_Glyph_To_Bitmap */ | |
/* */ | |
/* <Description> */ | |
/* Convert a given glyph object to a bitmap glyph object. */ | |
/* */ | |
/* <InOut> */ | |
/* the_glyph :: A pointer to a handle to the target glyph. */ | |
/* */ | |
/* <Input> */ | |
/* render_mode :: An enumeration that describes how the data is */ | |
/* rendered. */ | |
/* */ | |
/* origin :: A pointer to a vector used to translate the glyph */ | |
/* image before rendering. Can be~0 (if no */ | |
/* translation). The origin is expressed in */ | |
/* 26.6 pixels. */ | |
/* */ | |
/* destroy :: A boolean that indicates that the original glyph */ | |
/* image should be destroyed by this function. It is */ | |
/* never destroyed in case of error. */ | |
/* */ | |
/* <Return> */ | |
/* FreeType error code. 0~means success. */ | |
/* */ | |
/* <Note> */ | |
/* This function does nothing if the glyph format isn't scalable. */ | |
/* */ | |
/* The glyph image is translated with the `origin' vector before */ | |
/* rendering. */ | |
/* */ | |
/* The first parameter is a pointer to an @FT_Glyph handle, that will */ | |
/* be _replaced_ by this function (with newly allocated data). */ | |
/* Typically, you would use (omitting error handling): */ | |
/* */ | |
/* */ | |
/* { */ | |
/* FT_Glyph glyph; */ | |
/* FT_BitmapGlyph glyph_bitmap; */ | |
/* */ | |
/* */ | |
/* // load glyph */ | |
/* error = FT_Load_Char( face, glyph_index, FT_LOAD_DEFAUT ); */ | |
/* */ | |
/* // extract glyph image */ | |
/* error = FT_Get_Glyph( face->glyph, &glyph ); */ | |
/* */ | |
/* // convert to a bitmap (default render mode + destroying old) */ | |
/* if ( glyph->format != FT_GLYPH_FORMAT_BITMAP ) */ | |
/* { */ | |
/* error = FT_Glyph_To_Bitmap( &glyph, FT_RENDER_MODE_NORMAL, */ | |
/* 0, 1 ); */ | |
/* if ( error ) // `glyph' unchanged */ | |
/* ... */ | |
/* } */ | |
/* */ | |
/* // access bitmap content by typecasting */ | |
/* glyph_bitmap = (FT_BitmapGlyph)glyph; */ | |
/* */ | |
/* // do funny stuff with it, like blitting/drawing */ | |
/* ... */ | |
/* */ | |
/* // discard glyph image (bitmap or not) */ | |
/* FT_Done_Glyph( glyph ); */ | |
/* } */ | |
/* */ | |
/* */ | |
/* Here another example, again without error handling: */ | |
/* */ | |
/* */ | |
/* { */ | |
/* FT_Glyph glyphs[MAX_GLYPHS] */ | |
/* */ | |
/* */ | |
/* ... */ | |
/* */ | |
/* for ( idx = 0; i < MAX_GLYPHS; i++ ) */ | |
/* error = FT_Load_Glyph( face, idx, FT_LOAD_DEFAULT ) || */ | |
/* FT_Get_Glyph ( face->glyph, &glyph[idx] ); */ | |
/* */ | |
/* ... */ | |
/* */ | |
/* for ( idx = 0; i < MAX_GLYPHS; i++ ) */ | |
/* { */ | |
/* FT_Glyph bitmap = glyphs[idx]; */ | |
/* */ | |
/* */ | |
/* ... */ | |
/* */ | |
/* // after this call, `bitmap' no longer points into */ | |
/* // the `glyphs' array (and the old value isn't destroyed) */ | |
/* FT_Glyph_To_Bitmap( &bitmap, FT_RENDER_MODE_MONO, 0, 0 ); */ | |
/* */ | |
/* ... */ | |
/* */ | |
/* FT_Done_Glyph( bitmap ); */ | |
/* } */ | |
/* */ | |
/* ... */ | |
/* */ | |
/* for ( idx = 0; i < MAX_GLYPHS; i++ ) */ | |
/* FT_Done_Glyph( glyphs[idx] ); */ | |
/* } */ | |
/* */ | |
FT_EXPORT( FT_Error ) | |
FT_Glyph_To_Bitmap( FT_Glyph* the_glyph, | |
FT_Render_Mode render_mode, | |
FT_Vector* origin, | |
FT_Bool destroy ); | |
/*************************************************************************/ | |
/* */ | |
/* <Function> */ | |
/* FT_Done_Glyph */ | |
/* */ | |
/* <Description> */ | |
/* Destroy a given glyph. */ | |
/* */ | |
/* <Input> */ | |
/* glyph :: A handle to the target glyph object. */ | |
/* */ | |
FT_EXPORT( void ) | |
FT_Done_Glyph( FT_Glyph glyph ); | |
/* */ | |
/* other helpful functions */ | |
/*************************************************************************/ | |
/* */ | |
/* <Section> */ | |
/* computations */ | |
/* */ | |
/*************************************************************************/ | |
/*************************************************************************/ | |
/* */ | |
/* <Function> */ | |
/* FT_Matrix_Multiply */ | |
/* */ | |
/* <Description> */ | |
/* Perform the matrix operation `b = a*b'. */ | |
/* */ | |
/* <Input> */ | |
/* a :: A pointer to matrix `a'. */ | |
/* */ | |
/* <InOut> */ | |
/* b :: A pointer to matrix `b'. */ | |
/* */ | |
/* <Note> */ | |
/* The result is undefined if either `a' or `b' is zero. */ | |
/* */ | |
FT_EXPORT( void ) | |
FT_Matrix_Multiply( const FT_Matrix* a, | |
FT_Matrix* b ); | |
/*************************************************************************/ | |
/* */ | |
/* <Function> */ | |
/* FT_Matrix_Invert */ | |
/* */ | |
/* <Description> */ | |
/* Invert a 2x2 matrix. Return an error if it can't be inverted. */ | |
/* */ | |
/* <InOut> */ | |
/* matrix :: A pointer to the target matrix. Remains untouched in */ | |
/* case of error. */ | |
/* */ | |
/* <Return> */ | |
/* FreeType error code. 0~means success. */ | |
/* */ | |
FT_EXPORT( FT_Error ) | |
FT_Matrix_Invert( FT_Matrix* matrix ); | |
/* */ | |
FT_END_HEADER | |
#endif /* __FTGLYPH_H__ */ | |
/* END */ | |
/* Local Variables: */ | |
/* coding: utf-8 */ | |
/* End: */ |