| /**************************************************************************** |
| * |
| * ttobjs.h |
| * |
| * Objects manager (specification). |
| * |
| * Copyright (C) 1996-2022 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 TTOBJS_H_ |
| #define TTOBJS_H_ |
| |
| |
| #include <freetype/internal/ftobjs.h> |
| #include <freetype/internal/tttypes.h> |
| |
| |
| FT_BEGIN_HEADER |
| |
| |
| /************************************************************************** |
| * |
| * @Type: |
| * TT_Driver |
| * |
| * @Description: |
| * A handle to a TrueType driver object. |
| */ |
| typedef struct TT_DriverRec_* TT_Driver; |
| |
| |
| /************************************************************************** |
| * |
| * @Type: |
| * TT_GlyphSlot |
| * |
| * @Description: |
| * A handle to a TrueType glyph slot object. |
| * |
| * @Note: |
| * This is a direct typedef of FT_GlyphSlot, as there is nothing |
| * specific about the TrueType glyph slot. |
| */ |
| typedef FT_GlyphSlot TT_GlyphSlot; |
| |
| |
| /************************************************************************** |
| * |
| * @Struct: |
| * TT_GraphicsState |
| * |
| * @Description: |
| * The TrueType graphics state used during bytecode interpretation. |
| */ |
| typedef struct TT_GraphicsState_ |
| { |
| FT_UShort rp0; |
| FT_UShort rp1; |
| FT_UShort rp2; |
| |
| FT_UnitVector dualVector; |
| FT_UnitVector projVector; |
| FT_UnitVector freeVector; |
| |
| FT_Long loop; |
| FT_F26Dot6 minimum_distance; |
| FT_Int round_state; |
| |
| FT_Bool auto_flip; |
| FT_F26Dot6 control_value_cutin; |
| FT_F26Dot6 single_width_cutin; |
| FT_F26Dot6 single_width_value; |
| FT_UShort delta_base; |
| FT_UShort delta_shift; |
| |
| FT_Byte instruct_control; |
| /* According to Greg Hitchcock from Microsoft, the `scan_control' */ |
| /* variable as documented in the TrueType specification is a 32-bit */ |
| /* integer; the high-word part holds the SCANTYPE value, the low-word */ |
| /* part the SCANCTRL value. We separate it into two fields. */ |
| FT_Bool scan_control; |
| FT_Int scan_type; |
| |
| FT_UShort gep0; |
| FT_UShort gep1; |
| FT_UShort gep2; |
| |
| } TT_GraphicsState; |
| |
| |
| #ifdef TT_USE_BYTECODE_INTERPRETER |
| |
| FT_LOCAL( void ) |
| tt_glyphzone_done( TT_GlyphZone zone ); |
| |
| FT_LOCAL( FT_Error ) |
| tt_glyphzone_new( FT_Memory memory, |
| FT_UShort maxPoints, |
| FT_Short maxContours, |
| TT_GlyphZone zone ); |
| |
| #endif /* TT_USE_BYTECODE_INTERPRETER */ |
| |
| |
| |
| /************************************************************************** |
| * |
| * EXECUTION SUBTABLES |
| * |
| * These sub-tables relate to instruction execution. |
| * |
| */ |
| |
| |
| #define TT_MAX_CODE_RANGES 3 |
| |
| |
| /************************************************************************** |
| * |
| * There can only be 3 active code ranges at once: |
| * - the Font Program |
| * - the CVT Program |
| * - a glyph's instructions set |
| */ |
| typedef enum TT_CodeRange_Tag_ |
| { |
| tt_coderange_none = 0, |
| tt_coderange_font, |
| tt_coderange_cvt, |
| tt_coderange_glyph |
| |
| } TT_CodeRange_Tag; |
| |
| |
| typedef struct TT_CodeRange_ |
| { |
| FT_Byte* base; |
| FT_Long size; |
| |
| } TT_CodeRange; |
| |
| typedef TT_CodeRange TT_CodeRangeTable[TT_MAX_CODE_RANGES]; |
| |
| |
| /************************************************************************** |
| * |
| * Defines a function/instruction definition record. |
| */ |
| typedef struct TT_DefRecord_ |
| { |
| FT_Int range; /* in which code range is it located? */ |
| FT_Long start; /* where does it start? */ |
| FT_Long end; /* where does it end? */ |
| FT_UInt opc; /* function #, or instruction code */ |
| FT_Bool active; /* is it active? */ |
| FT_Bool inline_delta; /* is function that defines inline delta? */ |
| FT_ULong sph_fdef_flags; /* flags to identify special functions */ |
| |
| } TT_DefRecord, *TT_DefArray; |
| |
| |
| /************************************************************************** |
| * |
| * Subglyph transformation record. |
| */ |
| typedef struct TT_Transform_ |
| { |
| FT_Fixed xx, xy; /* transformation matrix coefficients */ |
| FT_Fixed yx, yy; |
| FT_F26Dot6 ox, oy; /* offsets */ |
| |
| } TT_Transform; |
| |
| |
| /************************************************************************** |
| * |
| * A note regarding non-squared pixels: |
| * |
| * (This text will probably go into some docs at some time; for now, it |
| * is kept here to explain some definitions in the TT_Size_Metrics |
| * record). |
| * |
| * The CVT is a one-dimensional array containing values that control |
| * certain important characteristics in a font, like the height of all |
| * capitals, all lowercase letter, default spacing or stem width/height. |
| * |
| * These values are found in FUnits in the font file, and must be scaled |
| * to pixel coordinates before being used by the CVT and glyph programs. |
| * Unfortunately, when using distinct x and y resolutions (or distinct x |
| * and y pointsizes), there are two possible scalings. |
| * |
| * A first try was to implement a `lazy' scheme where all values were |
| * scaled when first used. However, while some values are always used |
| * in the same direction, some others are used under many different |
| * circumstances and orientations. |
| * |
| * I have found a simpler way to do the same, and it even seems to work |
| * in most of the cases: |
| * |
| * - All CVT values are scaled to the maximum ppem size. |
| * |
| * - When performing a read or write in the CVT, a ratio factor is used |
| * to perform adequate scaling. Example: |
| * |
| * x_ppem = 14 |
| * y_ppem = 10 |
| * |
| * We choose ppem = x_ppem = 14 as the CVT scaling size. All cvt |
| * entries are scaled to it. |
| * |
| * x_ratio = 1.0 |
| * y_ratio = y_ppem/ppem (< 1.0) |
| * |
| * We compute the current ratio like: |
| * |
| * - If projVector is horizontal, |
| * ratio = x_ratio = 1.0 |
| * |
| * - if projVector is vertical, |
| * ratio = y_ratio |
| * |
| * - else, |
| * ratio = sqrt( (proj.x * x_ratio) ^ 2 + (proj.y * y_ratio) ^ 2 ) |
| * |
| * Reading a cvt value returns |
| * ratio * cvt[index] |
| * |
| * Writing a cvt value in pixels: |
| * cvt[index] / ratio |
| * |
| * The current ppem is simply |
| * ratio * ppem |
| * |
| */ |
| |
| |
| /************************************************************************** |
| * |
| * Metrics used by the TrueType size and context objects. |
| */ |
| typedef struct TT_Size_Metrics_ |
| { |
| /* for non-square pixels */ |
| FT_Long x_ratio; |
| FT_Long y_ratio; |
| |
| FT_UShort ppem; /* maximum ppem size */ |
| FT_Long ratio; /* current ratio */ |
| FT_Fixed scale; |
| |
| FT_F26Dot6 compensations[4]; /* device-specific compensations */ |
| |
| FT_Bool valid; |
| |
| FT_Bool rotated; /* `is the glyph rotated?'-flag */ |
| FT_Bool stretched; /* `is the glyph stretched?'-flag */ |
| |
| } TT_Size_Metrics; |
| |
| |
| /************************************************************************** |
| * |
| * TrueType size class. |
| */ |
| typedef struct TT_SizeRec_ |
| { |
| FT_SizeRec root; |
| |
| /* we have our own copy of metrics so that we can modify */ |
| /* it without affecting auto-hinting (when used) */ |
| FT_Size_Metrics* metrics; /* for the current rendering mode */ |
| FT_Size_Metrics hinted_metrics; /* for the hinted rendering mode */ |
| |
| TT_Size_Metrics ttmetrics; |
| |
| FT_Byte* widthp; /* glyph widths from the hdmx table */ |
| |
| FT_ULong strike_index; /* 0xFFFFFFFF to indicate invalid */ |
| |
| #ifdef TT_USE_BYTECODE_INTERPRETER |
| |
| FT_Long point_size; /* for the `MPS' bytecode instruction */ |
| |
| FT_UInt num_function_defs; /* number of function definitions */ |
| FT_UInt max_function_defs; |
| TT_DefArray function_defs; /* table of function definitions */ |
| |
| FT_UInt num_instruction_defs; /* number of ins. definitions */ |
| FT_UInt max_instruction_defs; |
| TT_DefArray instruction_defs; /* table of ins. definitions */ |
| |
| FT_UInt max_func; |
| FT_UInt max_ins; |
| |
| TT_CodeRangeTable codeRangeTable; |
| |
| TT_GraphicsState GS; |
| |
| FT_ULong cvt_size; /* the scaled control value table */ |
| FT_Long* cvt; |
| |
| FT_UShort storage_size; /* The storage area is now part of */ |
| FT_Long* storage; /* the instance */ |
| |
| TT_GlyphZoneRec twilight; /* The instance's twilight zone */ |
| |
| TT_ExecContext context; |
| |
| /* if negative, `fpgm' (resp. `prep'), wasn't executed yet; */ |
| /* otherwise it is the returned error code */ |
| FT_Error bytecode_ready; |
| FT_Error cvt_ready; |
| |
| #endif /* TT_USE_BYTECODE_INTERPRETER */ |
| |
| } TT_SizeRec; |
| |
| |
| /************************************************************************** |
| * |
| * TrueType driver class. |
| */ |
| typedef struct TT_DriverRec_ |
| { |
| FT_DriverRec root; |
| |
| TT_GlyphZoneRec zone; /* glyph loader points zone */ |
| |
| FT_UInt interpreter_version; |
| |
| } TT_DriverRec; |
| |
| |
| /* Note: All of the functions below (except tt_size_reset()) are used */ |
| /* as function pointers in a FT_Driver_ClassRec. Therefore their */ |
| /* parameters are of types FT_Face, FT_Size, etc., rather than TT_Face, */ |
| /* TT_Size, etc., so that the compiler can confirm that the types and */ |
| /* number of parameters are correct. In all cases the FT_xxx types are */ |
| /* cast to their TT_xxx counterparts inside the functions since FreeType */ |
| /* will always use the TT driver to create them. */ |
| |
| |
| /************************************************************************** |
| * |
| * Face functions |
| */ |
| FT_LOCAL( FT_Error ) |
| tt_face_init( FT_Stream stream, |
| FT_Face ttface, /* TT_Face */ |
| FT_Int face_index, |
| FT_Int num_params, |
| FT_Parameter* params ); |
| |
| FT_LOCAL( void ) |
| tt_face_done( FT_Face ttface ); /* TT_Face */ |
| |
| |
| /************************************************************************** |
| * |
| * Size functions |
| */ |
| FT_LOCAL( FT_Error ) |
| tt_size_init( FT_Size ttsize ); /* TT_Size */ |
| |
| FT_LOCAL( void ) |
| tt_size_done( FT_Size ttsize ); /* TT_Size */ |
| |
| #ifdef TT_USE_BYTECODE_INTERPRETER |
| |
| FT_LOCAL( FT_Error ) |
| tt_size_run_fpgm( TT_Size size, |
| FT_Bool pedantic ); |
| |
| FT_LOCAL( FT_Error ) |
| tt_size_run_prep( TT_Size size, |
| FT_Bool pedantic ); |
| |
| FT_LOCAL( FT_Error ) |
| tt_size_ready_bytecode( TT_Size size, |
| FT_Bool pedantic ); |
| |
| #endif /* TT_USE_BYTECODE_INTERPRETER */ |
| |
| FT_LOCAL( FT_Error ) |
| tt_size_reset( TT_Size size, |
| FT_Bool only_height ); |
| |
| |
| /************************************************************************** |
| * |
| * Driver functions |
| */ |
| FT_LOCAL( FT_Error ) |
| tt_driver_init( FT_Module ttdriver ); /* TT_Driver */ |
| |
| FT_LOCAL( void ) |
| tt_driver_done( FT_Module ttdriver ); /* TT_Driver */ |
| |
| |
| /************************************************************************** |
| * |
| * Slot functions |
| */ |
| FT_LOCAL( FT_Error ) |
| tt_slot_init( FT_GlyphSlot slot ); |
| |
| |
| /* auxiliary */ |
| #define IS_HINTED( flags ) ( ( flags & FT_LOAD_NO_HINTING ) == 0 ) |
| |
| |
| FT_END_HEADER |
| |
| #endif /* TTOBJS_H_ */ |
| |
| |
| /* END */ |
