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Diffstat (limited to 'src/cff/cf2blues.h')
| -rw-r--r-- | src/cff/cf2blues.h | 185 |
1 files changed, 185 insertions, 0 deletions
diff --git a/src/cff/cf2blues.h b/src/cff/cf2blues.h new file mode 100644 index 0000000..2f38fca --- /dev/null +++ b/src/cff/cf2blues.h @@ -0,0 +1,185 @@ +/***************************************************************************/ +/* */ +/* cf2blues.h */ +/* */ +/* Adobe's code for handling Blue Zones (specification). */ +/* */ +/* Copyright 2009-2013 Adobe Systems Incorporated. */ +/* */ +/* This software, and all works of authorship, whether in source or */ +/* object code form as indicated by the copyright notice(s) included */ +/* herein (collectively, the "Work") is made available, and may only be */ +/* used, modified, and distributed under the FreeType Project License, */ +/* LICENSE.TXT. Additionally, subject to the terms and conditions of the */ +/* FreeType Project License, each contributor to the Work hereby grants */ +/* to any individual or legal entity exercising permissions granted by */ +/* the FreeType Project License and this section (hereafter, "You" or */ +/* "Your") a perpetual, worldwide, non-exclusive, no-charge, */ +/* royalty-free, irrevocable (except as stated in this section) patent */ +/* license to make, have made, use, offer to sell, sell, import, and */ +/* otherwise transfer the Work, where such license applies only to those */ +/* patent claims licensable by such contributor that are necessarily */ +/* infringed by their contribution(s) alone or by combination of their */ +/* contribution(s) with the Work to which such contribution(s) was */ +/* submitted. If You institute patent litigation against any entity */ +/* (including a cross-claim or counterclaim in a lawsuit) alleging that */ +/* the Work or a contribution incorporated within the Work constitutes */ +/* direct or contributory patent infringement, then any patent licenses */ +/* granted to You under this License for that Work shall terminate as of */ +/* the date such litigation is filed. */ +/* */ +/* By using, modifying, or distributing the Work you indicate that you */ +/* have read and understood the terms and conditions of the */ +/* FreeType Project License as well as those provided in this section, */ +/* and you accept them fully. */ +/* */ +/***************************************************************************/ + + + /* + * A `CF2_Blues' object stores the blue zones (horizontal alignment + * zones) of a font. These are specified in the CFF private dictionary + * by `BlueValues', `OtherBlues', `FamilyBlues', and `FamilyOtherBlues'. + * Each zone is defined by a top and bottom edge in character space. + * Further, each zone is either a top zone or a bottom zone, as recorded + * by `bottomZone'. + * + * The maximum number of `BlueValues' and `FamilyBlues' is 7 each. + * However, these are combined to produce a total of 7 zones. + * Similarly, the maximum number of `OtherBlues' and `FamilyOtherBlues' + * is 5 and these are combined to produce an additional 5 zones. + * + * Blue zones are used to `capture' hints and force them to a common + * alignment point. This alignment is recorded in device space in + * `dsFlatEdge'. Except for this value, a `CF2_Blues' object could be + * constructed independently of scaling. Construction may occur once + * the matrix is known. Other features implemented in the Capture + * method are overshoot suppression, overshoot enforcement, and Blue + * Boost. + * + * Capture is determined by `BlueValues' and `OtherBlues', but the + * alignment point may be adjusted to the scaled flat edge of + * `FamilyBlues' or `FamilyOtherBlues'. No alignment is done to the + * curved edge of a zone. + * + */ + + +#ifndef __CF2BLUES_H__ +#define __CF2BLUES_H__ + + +#include "cf2glue.h" + + +FT_BEGIN_HEADER + + + /* + * `CF2_Hint' is shared by `cf2hints.h' and + * `cf2blues.h', but `cf2blues.h' depends on + * `cf2hints.h', so define it here. Note: The typedef is in + * `cf2glue.h'. + * + */ + enum + { + CF2_GhostBottom = 0x1, /* a single bottom edge */ + CF2_GhostTop = 0x2, /* a single top edge */ + CF2_PairBottom = 0x4, /* the bottom edge of a stem hint */ + CF2_PairTop = 0x8, /* the top edge of a stem hint */ + CF2_Locked = 0x10, /* this edge has been aligned */ + /* by a blue zone */ + CF2_Synthetic = 0x20 /* this edge was synthesized */ + }; + + + /* + * Default value for OS/2 typoAscender/Descender when their difference + * is not equal to `unitsPerEm'. The default is based on -250 and 1100 + * in `CF2_Blues', assuming 1000 units per em here. + * + */ + enum + { + CF2_ICF_Top = cf2_intToFixed( 880 ), + CF2_ICF_Bottom = cf2_intToFixed( -120 ) + }; + + + /* + * Constant used for hint adjustment and for synthetic em box hint + * placement. + */ +#define CF2_MIN_COUNTER cf2_floatToFixed( 0.5 ) + + + /* shared typedef is in cf2glue.h */ + struct CF2_HintRec_ + { + CF2_UInt flags; /* attributes of the edge */ + size_t index; /* index in original stem hint array */ + /* (if not synthetic) */ + CF2_Fixed csCoord; + CF2_Fixed dsCoord; + CF2_Fixed scale; + }; + + + typedef struct CF2_BlueRec_ + { + CF2_Fixed csBottomEdge; + CF2_Fixed csTopEdge; + CF2_Fixed csFlatEdge; /* may be from either local or Family zones */ + CF2_Fixed dsFlatEdge; /* top edge of bottom zone or bottom edge */ + /* of top zone (rounded) */ + FT_Bool bottomZone; + + } CF2_BlueRec; + + + /* max total blue zones is 12 */ + enum + { + CF2_MAX_BLUES = 7, + CF2_MAX_OTHERBLUES = 5 + }; + + + typedef struct CF2_BluesRec_ + { + CF2_Fixed scale; + CF2_UInt count; + FT_Bool suppressOvershoot; + FT_Bool doEmBoxHints; + + CF2_Fixed blueScale; + CF2_Fixed blueShift; + CF2_Fixed blueFuzz; + + CF2_Fixed boost; + + CF2_HintRec emBoxTopEdge; + CF2_HintRec emBoxBottomEdge; + + CF2_BlueRec zone[CF2_MAX_BLUES + CF2_MAX_OTHERBLUES]; + + } CF2_BluesRec, *CF2_Blues; + + + FT_LOCAL( void ) + cf2_blues_init( CF2_Blues blues, + CF2_Font font ); + FT_LOCAL( FT_Bool ) + cf2_blues_capture( const CF2_Blues blues, + CF2_Hint bottomHintEdge, + CF2_Hint topHintEdge ); + + +FT_END_HEADER + + +#endif /* __CF2BLUES_H__ */ + + +/* END */ |