diff -r a501f5ec7b34 -r 0f5961910e27 misc/libfreetype/src/autofit/afhints.h --- a/misc/libfreetype/src/autofit/afhints.h Tue Jul 16 11:14:27 2013 +0200 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,468 +0,0 @@ -/***************************************************************************/ -/* */ -/* afhints.h */ -/* */ -/* Auto-fitter hinting routines (specification). */ -/* */ -/* Copyright 2003-2008, 2010-2011 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 __AFHINTS_H__ -#define __AFHINTS_H__ - -#include "aftypes.h" - -#define xxAF_SORT_SEGMENTS - -FT_BEGIN_HEADER - - /* - * The definition of outline glyph hints. These are shared by all - * script analysis routines (until now). - */ - - typedef enum AF_Dimension_ - { - AF_DIMENSION_HORZ = 0, /* x coordinates, */ - /* i.e., vertical segments & edges */ - AF_DIMENSION_VERT = 1, /* y coordinates, */ - /* i.e., horizontal segments & edges */ - - AF_DIMENSION_MAX /* do not remove */ - - } AF_Dimension; - - - /* hint directions -- the values are computed so that two vectors are */ - /* in opposite directions iff `dir1 + dir2 == 0' */ - typedef enum AF_Direction_ - { - AF_DIR_NONE = 4, - AF_DIR_RIGHT = 1, - AF_DIR_LEFT = -1, - AF_DIR_UP = 2, - AF_DIR_DOWN = -2 - - } AF_Direction; - - - /* - * The following explanations are mostly taken from the article - * - * Real-Time Grid Fitting of Typographic Outlines - * - * by David Turner and Werner Lemberg - * - * http://www.tug.org/TUGboat/Articles/tb24-3/lemberg.pdf - * - * - * Segments - * - * `af_{cjk,latin,...}_hints_compute_segments' are the functions to - * find segments in an outline. A segment is a series of consecutive - * points that are approximately aligned along a coordinate axis. The - * analysis to do so is specific to a script. - * - * A segment must have at least two points, except in the case of - * `fake' segments that are generated to hint metrics appropriately, - * and which consist of a single point. - * - * - * Edges - * - * As soon as segments are defined, the auto-hinter groups them into - * edges. An edge corresponds to a single position on the main - * dimension that collects one or more segments (allowing for a small - * threshold). - * - * The auto-hinter first tries to grid fit edges, then to align - * segments on the edges unless it detects that they form a serif. - * - * `af_{cjk,latin,...}_hints_compute_edges' are the functions to find - * edges; they are specific to a script. - * - * - * A H - * | | - * | | - * | | - * | | - * C | | F - * +------<-----+ +-----<------+ - * | B G | - * | | - * | | - * +--------------->------------------+ - * D E - * - * - * Stems - * - * Segments need to be `linked' to other ones in order to detect stems. - * A stem is made of two segments that face each other in opposite - * directions and that are sufficiently close to each other. Using - * vocabulary from the TrueType specification, stem segments form a - * `black distance'. - * - * In the above ASCII drawing, the horizontal segments are BC, DE, and - * FG; the vertical segments are AB, CD, EF, and GH. - * - * Each segment has at most one `best' candidate to form a black - * distance, or no candidate at all. Notice that two distinct segments - * can have the same candidate, which frequently means a serif. - * - * A stem is recognized by the following condition: - * - * best segment_1 = segment_2 && best segment_2 = segment_1 - * - * The best candidate is stored in field `link' in structure - * `AF_Segment'. - * - * Stems are detected by `af_{cjk,latin,...}_hint_edges'. - * - * In the above ASCII drawing, the best candidate for both AB and CD is - * GH, while the best candidate for GH is AB. Similarly, the best - * candidate for EF and GH is AB, while the best candidate for AB is - * GH. - * - * - * Serifs - * - * On the opposite, a serif has - * - * best segment_1 = segment_2 && best segment_2 != segment_1 - * - * where segment_1 corresponds to the serif segment (CD and EF in the - * above ASCII drawing). - * - * The best candidate is stored in field `serif' in structure - * `AF_Segment' (and `link' is set to NULL). - * - * Serifs are detected by `af_{cjk,latin,...}_hint_edges'. - * - * - * Touched points - * - * A point is called `touched' if it has been processed somehow by the - * auto-hinter. It basically means that it shouldn't be moved again - * (or moved only under certain constraints to preserve the already - * applied processing). - * - * - * Flat and round segments - * - * Segments are `round' or `flat', depending on the series of points - * that define them. A segment is round if the next and previous point - * of an extremum (which can be either a single point or sequence of - * points) are both conic or cubic control points. Otherwise, a - * segment with an extremum is flat. - * - * - * Strong Points - * - * Experience has shown that points which are not part of an edge need - * to be interpolated linearly between their two closest edges, even if - * these are not part of the contour of those particular points. - * Typical candidates for this are - * - * - angle points (i.e., points where the `in' and `out' direction - * differ greatly) - * - * - inflection points (i.e., where the `in' and `out' angles are the - * same, but the curvature changes sign) - * - * `af_glyph_hints_align_strong_points' is the function which takes - * care of such situations; it is equivalent to the TrueType `IP' - * hinting instruction. - * - * - * Weak Points - * - * Other points in the outline must be interpolated using the - * coordinates of their previous and next unfitted contour neighbours. - * These are called `weak points' and are touched by the function - * `af_glyph_hints_align_weak_points', equivalent to the TrueType `IUP' - * hinting instruction. Typical candidates are control points and - * points on the contour without a major direction. - * - * The major effect is to reduce possible distortion caused by - * alignment of edges and strong points, thus weak points are processed - * after strong points. - */ - - - /* point hint flags */ - typedef enum AF_Flags_ - { - AF_FLAG_NONE = 0, - - /* point type flags */ - AF_FLAG_CONIC = 1 << 0, - AF_FLAG_CUBIC = 1 << 1, - AF_FLAG_CONTROL = AF_FLAG_CONIC | AF_FLAG_CUBIC, - - /* point extremum flags */ - AF_FLAG_EXTREMA_X = 1 << 2, - AF_FLAG_EXTREMA_Y = 1 << 3, - - /* point roundness flags */ - AF_FLAG_ROUND_X = 1 << 4, - AF_FLAG_ROUND_Y = 1 << 5, - - /* point touch flags */ - AF_FLAG_TOUCH_X = 1 << 6, - AF_FLAG_TOUCH_Y = 1 << 7, - - /* candidates for weak interpolation have this flag set */ - AF_FLAG_WEAK_INTERPOLATION = 1 << 8, - - /* all inflection points in the outline have this flag set */ - AF_FLAG_INFLECTION = 1 << 9 - - } AF_Flags; - - - /* edge hint flags */ - typedef enum AF_Edge_Flags_ - { - AF_EDGE_NORMAL = 0, - AF_EDGE_ROUND = 1 << 0, - AF_EDGE_SERIF = 1 << 1, - AF_EDGE_DONE = 1 << 2 - - } AF_Edge_Flags; - - - typedef struct AF_PointRec_* AF_Point; - typedef struct AF_SegmentRec_* AF_Segment; - typedef struct AF_EdgeRec_* AF_Edge; - - - typedef struct AF_PointRec_ - { - FT_UShort flags; /* point flags used by hinter */ - FT_Char in_dir; /* direction of inwards vector */ - FT_Char out_dir; /* direction of outwards vector */ - - FT_Pos ox, oy; /* original, scaled position */ - FT_Short fx, fy; /* original, unscaled position (font units) */ - FT_Pos x, y; /* current position */ - FT_Pos u, v; /* current (x,y) or (y,x) depending on context */ - - AF_Point next; /* next point in contour */ - AF_Point prev; /* previous point in contour */ - - } AF_PointRec; - - - typedef struct AF_SegmentRec_ - { - FT_Byte flags; /* edge/segment flags for this segment */ - FT_Char dir; /* segment direction */ - FT_Short pos; /* position of segment */ - FT_Short min_coord; /* minimum coordinate of segment */ - FT_Short max_coord; /* maximum coordinate of segment */ - FT_Short height; /* the hinted segment height */ - - AF_Edge edge; /* the segment's parent edge */ - AF_Segment edge_next; /* link to next segment in parent edge */ - - AF_Segment link; /* (stem) link segment */ - AF_Segment serif; /* primary segment for serifs */ - FT_Pos num_linked; /* number of linked segments */ - FT_Pos score; /* used during stem matching */ - FT_Pos len; /* used during stem matching */ - - AF_Point first; /* first point in edge segment */ - AF_Point last; /* last point in edge segment */ - AF_Point* contour; /* ptr to first point of segment's contour */ - - } AF_SegmentRec; - - - typedef struct AF_EdgeRec_ - { - FT_Short fpos; /* original, unscaled position (font units) */ - FT_Pos opos; /* original, scaled position */ - FT_Pos pos; /* current position */ - - FT_Byte flags; /* edge flags */ - FT_Char dir; /* edge direction */ - FT_Fixed scale; /* used to speed up interpolation between edges */ - AF_Width blue_edge; /* non-NULL if this is a blue edge */ - - AF_Edge link; /* link edge */ - AF_Edge serif; /* primary edge for serifs */ - FT_Short num_linked; /* number of linked edges */ - FT_Int score; /* used during stem matching */ - - AF_Segment first; /* first segment in edge */ - AF_Segment last; /* last segment in edge */ - - } AF_EdgeRec; - - - typedef struct AF_AxisHintsRec_ - { - FT_Int num_segments; /* number of used segments */ - FT_Int max_segments; /* number of allocated segments */ - AF_Segment segments; /* segments array */ -#ifdef AF_SORT_SEGMENTS - FT_Int mid_segments; -#endif - - FT_Int num_edges; /* number of used edges */ - FT_Int max_edges; /* number of allocated edges */ - AF_Edge edges; /* edges array */ - - AF_Direction major_dir; /* either vertical or horizontal */ - - } AF_AxisHintsRec, *AF_AxisHints; - - - typedef struct AF_GlyphHintsRec_ - { - FT_Memory memory; - - FT_Fixed x_scale; - FT_Pos x_delta; - - FT_Fixed y_scale; - FT_Pos y_delta; - - FT_Int max_points; /* number of allocated points */ - FT_Int num_points; /* number of used points */ - AF_Point points; /* points array */ - - FT_Int max_contours; /* number of allocated contours */ - FT_Int num_contours; /* number of used contours */ - AF_Point* contours; /* contours array */ - - AF_AxisHintsRec axis[AF_DIMENSION_MAX]; - - FT_UInt32 scaler_flags; /* copy of scaler flags */ - FT_UInt32 other_flags; /* free for script-specific */ - /* implementations */ - AF_ScriptMetrics metrics; - - FT_Pos xmin_delta; /* used for warping */ - FT_Pos xmax_delta; - - } AF_GlyphHintsRec; - - -#define AF_HINTS_TEST_SCALER( h, f ) ( (h)->scaler_flags & (f) ) -#define AF_HINTS_TEST_OTHER( h, f ) ( (h)->other_flags & (f) ) - - -#ifdef FT_DEBUG_AUTOFIT - -#define AF_HINTS_DO_HORIZONTAL( h ) \ - ( !_af_debug_disable_horz_hints && \ - !AF_HINTS_TEST_SCALER( h, AF_SCALER_FLAG_NO_HORIZONTAL ) ) - -#define AF_HINTS_DO_VERTICAL( h ) \ - ( !_af_debug_disable_vert_hints && \ - !AF_HINTS_TEST_SCALER( h, AF_SCALER_FLAG_NO_VERTICAL ) ) - -#define AF_HINTS_DO_ADVANCE( h ) \ - !AF_HINTS_TEST_SCALER( h, AF_SCALER_FLAG_NO_ADVANCE ) - -#define AF_HINTS_DO_BLUES( h ) ( !_af_debug_disable_blue_hints ) - -#else /* !FT_DEBUG_AUTOFIT */ - -#define AF_HINTS_DO_HORIZONTAL( h ) \ - !AF_HINTS_TEST_SCALER( h, AF_SCALER_FLAG_NO_HORIZONTAL ) - -#define AF_HINTS_DO_VERTICAL( h ) \ - !AF_HINTS_TEST_SCALER( h, AF_SCALER_FLAG_NO_VERTICAL ) - -#define AF_HINTS_DO_ADVANCE( h ) \ - !AF_HINTS_TEST_SCALER( h, AF_SCALER_FLAG_NO_ADVANCE ) - -#define AF_HINTS_DO_BLUES( h ) 1 - -#endif /* !FT_DEBUG_AUTOFIT */ - - - FT_LOCAL( AF_Direction ) - af_direction_compute( FT_Pos dx, - FT_Pos dy ); - - - FT_LOCAL( FT_Error ) - af_axis_hints_new_segment( AF_AxisHints axis, - FT_Memory memory, - AF_Segment *asegment ); - - FT_LOCAL( FT_Error) - af_axis_hints_new_edge( AF_AxisHints axis, - FT_Int fpos, - AF_Direction dir, - FT_Memory memory, - AF_Edge *edge ); - - FT_LOCAL( void ) - af_glyph_hints_init( AF_GlyphHints hints, - FT_Memory memory ); - - FT_LOCAL( void ) - af_glyph_hints_rescale( AF_GlyphHints hints, - AF_ScriptMetrics metrics ); - - FT_LOCAL( FT_Error ) - af_glyph_hints_reload( AF_GlyphHints hints, - FT_Outline* outline ); - - FT_LOCAL( void ) - af_glyph_hints_save( AF_GlyphHints hints, - FT_Outline* outline ); - - FT_LOCAL( void ) - af_glyph_hints_align_edge_points( AF_GlyphHints hints, - AF_Dimension dim ); - - FT_LOCAL( void ) - af_glyph_hints_align_strong_points( AF_GlyphHints hints, - AF_Dimension dim ); - - FT_LOCAL( void ) - af_glyph_hints_align_weak_points( AF_GlyphHints hints, - AF_Dimension dim ); - -#ifdef AF_CONFIG_OPTION_USE_WARPER - FT_LOCAL( void ) - af_glyph_hints_scale_dim( AF_GlyphHints hints, - AF_Dimension dim, - FT_Fixed scale, - FT_Pos delta ); -#endif - - FT_LOCAL( void ) - af_glyph_hints_done( AF_GlyphHints hints ); - -/* */ - -#define AF_SEGMENT_LEN( seg ) ( (seg)->max_coord - (seg)->min_coord ) - -#define AF_SEGMENT_DIST( seg1, seg2 ) ( ( (seg1)->pos > (seg2)->pos ) \ - ? (seg1)->pos - (seg2)->pos \ - : (seg2)->pos - (seg1)->pos ) - - -FT_END_HEADER - -#endif /* __AFHINTS_H__ */ - - -/* END */