| /***************************************************************************/ |
| /* */ |
| /* ftglyph.h */ |
| /* */ |
| /* FreeType convenience functions to handle glyphs (specification). */ |
| /* */ |
| /* Copyright 1996-2001 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 |
| |
| |
| 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 float 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 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 the 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 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. */ |
| /* */ |
| /* <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. */ |
| /* */ |
| /* <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> */ |
| /* Transforms 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 (the glyph format is not scalable if it is */ |
| /* not zero). */ |
| /* */ |
| /* <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 ); |
| |
| /* */ |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* FT_Glyph_Get_CBox */ |
| /* */ |
| /* <Description> */ |
| /* Returns a glyph's `control box'. The control box encloses all the */ |
| /* outline's points, including Bezier 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 */ |
| /* which contains Bezier 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 which 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. */ |
| /* */ |
| /* If `bbox_mode' is set to `ft_glyph_bbox_subpixels' the bbox */ |
| /* coordinates are returned in 26.6 pixels (i.e. 1/64th of pixels). */ |
| /* */ |
| /* 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'. */ |
| /* */ |
| /* The default value for `bbox_mode' is `ft_glyph_bbox_pixels'. */ |
| /* */ |
| enum |
| { |
| ft_glyph_bbox_unscaled = 0, /* return unscaled font units */ |
| ft_glyph_bbox_subpixels = 0, /* return unfitted 26.6 coordinates */ |
| ft_glyph_bbox_gridfit = 1, /* return grid-fitted 26.6 coordinates */ |
| ft_glyph_bbox_truncate = 2, /* return coordinates in integer pixels */ |
| ft_glyph_bbox_pixels = 3 /* return grid-fitted pixel coordinates */ |
| }; |
| |
| |
| FT_EXPORT( void ) |
| FT_Glyph_Get_CBox( FT_Glyph glyph, |
| FT_UInt bbox_mode, |
| FT_BBox *acbox ); |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* FT_Glyph_To_Bitmap */ |
| /* */ |
| /* <Description> */ |
| /* Converts a given glyph object to a bitmap glyph object. */ |
| /* */ |
| /* <InOut> */ |
| /* the_glyph :: A pointer to a handle to the target glyph. */ |
| /* */ |
| /* <Input> */ |
| /* render_mode :: A set of bit flags that describe how the data is */ |
| /* */ |
| /* */ |
| /* 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> */ |
| /* The glyph image is translated with the `origin' vector before */ |
| /* rendering. In case of error, it it translated back to its */ |
| /* original position and the glyph is left untouched. */ |
| /* */ |
| /* The first parameter is a pointer to a FT_Glyph handle, that will */ |
| /* be replaced by this function. 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 + destroy old) */ |
| /* if ( glyph->format != ft_glyph_format_bitmap ) */ |
| /* { */ |
| /* error = FT_Glyph_To_Bitmap( &glyph, ft_render_mode_default, */ |
| /* 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 ); */ |
| /* } */ |
| /* */ |
| /* */ |
| /* This function will always fail if the glyph's format isn't */ |
| /* scalable. */ |
| /* */ |
| FT_EXPORT( FT_Error ) |
| FT_Glyph_To_Bitmap( FT_Glyph* the_glyph, |
| FT_ULong render_mode, |
| FT_Vector* origin, |
| FT_Bool destroy ); |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* FT_Done_Glyph */ |
| /* */ |
| /* <Description> */ |
| /* Destroys 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> */ |
| /* Performs 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( FT_Matrix* a, |
| FT_Matrix* b ); |
| |
| |
| /*************************************************************************/ |
| /* */ |
| /* <Function> */ |
| /* FT_Matrix_Invert */ |
| /* */ |
| /* <Description> */ |
| /* Inverts a 2x2 matrix. Returns 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 */ |
