diff options
Diffstat (limited to 'src/freetype/pshints.c')
| -rw-r--r-- | src/freetype/pshints.c | 1939 |
1 files changed, 1939 insertions, 0 deletions
diff --git a/src/freetype/pshints.c b/src/freetype/pshints.c new file mode 100644 index 0000000..3762f35 --- /dev/null +++ b/src/freetype/pshints.c @@ -0,0 +1,1939 @@ +/***************************************************************************/ +/* */ +/* pshints.c */ +/* */ +/* Adobe's code for handling CFF hints (body). */ +/* */ +/* Copyright 2007-2014 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. */ +/* */ +/***************************************************************************/ + + +#include "psft.h" +#include FT_INTERNAL_DEBUG_H + +#include "psglue.h" +#include "psfont.h" +#include "pshints_.h" +#include "psintrp.h" + + + /*************************************************************************/ + /* */ + /* The macro FT_COMPONENT is used in trace mode. It is an implicit */ + /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log */ + /* messages during execution. */ + /* */ +#undef FT_COMPONENT +#define FT_COMPONENT trace_cf2hints + + + typedef struct CF2_HintMoveRec_ + { + size_t j; /* index of upper hint map edge */ + CF2_Fixed moveUp; /* adjustment to optimum position */ + + } CF2_HintMoveRec, *CF2_HintMove; + + + /* Compute angular momentum for winding order detection. It is called */ + /* for all lines and curves, but not necessarily in element order. */ + static CF2_Int + cf2_getWindingMomentum( CF2_Fixed x1, + CF2_Fixed y1, + CF2_Fixed x2, + CF2_Fixed y2 ) + { + /* cross product of pt1 position from origin with pt2 position from */ + /* pt1; we reduce the precision so that the result fits into 32 bits */ + + return ( x1 >> 16 ) * ( SUB_INT32( y2, y1 ) >> 16 ) - + ( y1 >> 16 ) * ( SUB_INT32( x2, x1 ) >> 16 ); + } + + + /* + * Construct from a StemHint; this is used as a parameter to + * `cf2_blues_capture'. + * `hintOrigin' is the character space displacement of a seac accent. + * Adjust stem hint for darkening here. + * + */ + static void + cf2_hint_init( CF2_Hint hint, + const CF2_ArrStack stemHintArray, + size_t indexStemHint, + const CF2_Font font, + CF2_Fixed hintOrigin, + CF2_Fixed scale, + FT_Bool bottom ) + { + CF2_Fixed width; + const CF2_StemHintRec* stemHint; + + + FT_ZERO( hint ); + + stemHint = (const CF2_StemHintRec*)cf2_arrstack_getPointer( + stemHintArray, + indexStemHint ); + + width = SUB_INT32( stemHint->max, stemHint->min ); + + if ( width == cf2_intToFixed( -21 ) ) + { + /* ghost bottom */ + + if ( bottom ) + { + hint->csCoord = stemHint->max; + hint->flags = CF2_GhostBottom; + } + else + hint->flags = 0; + } + + else if ( width == cf2_intToFixed( -20 ) ) + { + /* ghost top */ + + if ( bottom ) + hint->flags = 0; + else + { + hint->csCoord = stemHint->min; + hint->flags = CF2_GhostTop; + } + } + + else if ( width < 0 ) + { + /* inverted pair */ + + /* + * Hints with negative widths were produced by an early version of a + * non-Adobe font tool. The Type 2 spec allows edge (ghost) hints + * with negative widths, but says + * + * All other negative widths have undefined meaning. + * + * CoolType has a silent workaround that negates the hint width; for + * permissive mode, we do the same here. + * + * Note: Such fonts cannot use ghost hints, but should otherwise work. + * Note: Some poor hints in our faux fonts can produce negative + * widths at some blends. For example, see a light weight of + * `u' in ASerifMM. + * + */ + if ( bottom ) + { + hint->csCoord = stemHint->max; + hint->flags = CF2_PairBottom; + } + else + { + hint->csCoord = stemHint->min; + hint->flags = CF2_PairTop; + } + } + + else + { + /* normal pair */ + + if ( bottom ) + { + hint->csCoord = stemHint->min; + hint->flags = CF2_PairBottom; + } + else + { + hint->csCoord = stemHint->max; + hint->flags = CF2_PairTop; + } + } + + /* Now that ghost hints have been detected, adjust this edge for */ + /* darkening. Bottoms are not changed; tops are incremented by twice */ + /* `darkenY'. */ + if ( cf2_hint_isTop( hint ) ) + hint->csCoord = ADD_INT32( hint->csCoord, 2 * font->darkenY ); + + hint->csCoord = ADD_INT32( hint->csCoord, hintOrigin ); + hint->scale = scale; + hint->index = indexStemHint; /* index in original stem hint array */ + + /* if original stem hint has been used, use the same position */ + if ( hint->flags != 0 && stemHint->used ) + { + if ( cf2_hint_isTop( hint ) ) + hint->dsCoord = stemHint->maxDS; + else + hint->dsCoord = stemHint->minDS; + + cf2_hint_lock( hint ); + } + else + hint->dsCoord = FT_MulFix( hint->csCoord, scale ); + } + + + /* initialize an invalid hint map element */ + static void + cf2_hint_initZero( CF2_Hint hint ) + { + FT_ZERO( hint ); + } + + + FT_LOCAL_DEF( FT_Bool ) + cf2_hint_isValid( const CF2_Hint hint ) + { + return (FT_Bool)( hint->flags != 0 ); + } + + + static FT_Bool + cf2_hint_isPair( const CF2_Hint hint ) + { + return (FT_Bool)( ( hint->flags & + ( CF2_PairBottom | CF2_PairTop ) ) != 0 ); + } + + + static FT_Bool + cf2_hint_isPairTop( const CF2_Hint hint ) + { + return (FT_Bool)( ( hint->flags & CF2_PairTop ) != 0 ); + } + + + FT_LOCAL_DEF( FT_Bool ) + cf2_hint_isTop( const CF2_Hint hint ) + { + return (FT_Bool)( ( hint->flags & + ( CF2_PairTop | CF2_GhostTop ) ) != 0 ); + } + + + FT_LOCAL_DEF( FT_Bool ) + cf2_hint_isBottom( const CF2_Hint hint ) + { + return (FT_Bool)( ( hint->flags & + ( CF2_PairBottom | CF2_GhostBottom ) ) != 0 ); + } + + + static FT_Bool + cf2_hint_isLocked( const CF2_Hint hint ) + { + return (FT_Bool)( ( hint->flags & CF2_Locked ) != 0 ); + } + + + static FT_Bool + cf2_hint_isSynthetic( const CF2_Hint hint ) + { + return (FT_Bool)( ( hint->flags & CF2_Synthetic ) != 0 ); + } + + + FT_LOCAL_DEF( void ) + cf2_hint_lock( CF2_Hint hint ) + { + hint->flags |= CF2_Locked; + } + + + FT_LOCAL_DEF( void ) + cf2_hintmap_init( CF2_HintMap hintmap, + CF2_Font font, + CF2_HintMap initialMap, + CF2_ArrStack hintMoves, + CF2_Fixed scale ) + { + FT_ZERO( hintmap ); + + /* copy parameters from font instance */ + hintmap->hinted = font->hinted; + hintmap->scale = scale; + hintmap->font = font; + hintmap->initialHintMap = initialMap; + /* will clear in `cf2_hintmap_adjustHints' */ + hintmap->hintMoves = hintMoves; + } + + + static FT_Bool + cf2_hintmap_isValid( const CF2_HintMap hintmap ) + { + return hintmap->isValid; + } + + + static void + cf2_hintmap_dump( CF2_HintMap hintmap ) + { +#ifdef FT_DEBUG_LEVEL_TRACE + CF2_UInt i; + + + FT_TRACE6(( " index csCoord dsCoord scale flags\n" )); + + for ( i = 0; i < hintmap->count; i++ ) + { + CF2_Hint hint = &hintmap->edge[i]; + + + FT_TRACE6(( " %3d %7.2f %7.2f %5d %s%s%s%s\n", + hint->index, + hint->csCoord / 65536.0, + hint->dsCoord / ( hint->scale * 1.0 ), + hint->scale, + ( cf2_hint_isPair( hint ) ? "p" : "g" ), + ( cf2_hint_isTop( hint ) ? "t" : "b" ), + ( cf2_hint_isLocked( hint ) ? "L" : ""), + ( cf2_hint_isSynthetic( hint ) ? "S" : "" ) )); + } +#else + FT_UNUSED( hintmap ); +#endif + } + + + /* transform character space coordinate to device space using hint map */ + static CF2_Fixed + cf2_hintmap_map( CF2_HintMap hintmap, + CF2_Fixed csCoord ) + { + if ( hintmap->count == 0 || ! hintmap->hinted ) + { + /* there are no hints; use uniform scale and zero offset */ + return FT_MulFix( csCoord, hintmap->scale ); + } + else + { + /* start linear search from last hit */ + CF2_UInt i = hintmap->lastIndex; + + + FT_ASSERT( hintmap->lastIndex < CF2_MAX_HINT_EDGES ); + + /* search up */ + while ( i < hintmap->count - 1 && + csCoord >= hintmap->edge[i + 1].csCoord ) + i += 1; + + /* search down */ + while ( i > 0 && csCoord < hintmap->edge[i].csCoord ) + i -= 1; + + hintmap->lastIndex = i; + + if ( i == 0 && csCoord < hintmap->edge[0].csCoord ) + { + /* special case for points below first edge: use uniform scale */ + return ADD_INT32( FT_MulFix( SUB_INT32( csCoord, + hintmap->edge[0].csCoord ), + hintmap->scale ), + hintmap->edge[0].dsCoord ); + } + else + { + /* + * Note: entries with duplicate csCoord are allowed. + * Use edge[i], the highest entry where csCoord >= entry[i].csCoord + */ + return ADD_INT32( FT_MulFix( SUB_INT32( csCoord, + hintmap->edge[i].csCoord ), + hintmap->edge[i].scale ), + hintmap->edge[i].dsCoord ); + } + } + } + + + /* + * This hinting policy moves a hint pair in device space so that one of + * its two edges is on a device pixel boundary (its fractional part is + * zero). `cf2_hintmap_insertHint' guarantees no overlap in CS + * space. Ensure here that there is no overlap in DS. + * + * In the first pass, edges are adjusted relative to adjacent hints. + * Those that are below have already been adjusted. Those that are + * above have not yet been adjusted. If a hint above blocks an + * adjustment to an optimal position, we will try again in a second + * pass. The second pass is top-down. + * + */ + + static void + cf2_hintmap_adjustHints( CF2_HintMap hintmap ) + { + size_t i, j; + + + cf2_arrstack_clear( hintmap->hintMoves ); /* working storage */ + + /* + * First pass is bottom-up (font hint order) without look-ahead. + * Locked edges are already adjusted. + * Unlocked edges begin with dsCoord from `initialHintMap'. + * Save edges that are not optimally adjusted in `hintMoves' array, + * and process them in second pass. + */ + + for ( i = 0; i < hintmap->count; i++ ) + { + FT_Bool isPair = cf2_hint_isPair( &hintmap->edge[i] ); + + + /* index of upper edge (same value for ghost hint) */ + j = isPair ? i + 1 : i; + + FT_ASSERT( j < hintmap->count ); + FT_ASSERT( cf2_hint_isValid( &hintmap->edge[i] ) ); + FT_ASSERT( cf2_hint_isValid( &hintmap->edge[j] ) ); + FT_ASSERT( cf2_hint_isLocked( &hintmap->edge[i] ) == + cf2_hint_isLocked( &hintmap->edge[j] ) ); + + if ( !cf2_hint_isLocked( &hintmap->edge[i] ) ) + { + /* hint edge is not locked, we can adjust it */ + CF2_Fixed fracDown = cf2_fixedFraction( hintmap->edge[i].dsCoord ); + CF2_Fixed fracUp = cf2_fixedFraction( hintmap->edge[j].dsCoord ); + + /* calculate all four possibilities; moves down are negative */ + CF2_Fixed downMoveDown = 0 - fracDown; + CF2_Fixed upMoveDown = 0 - fracUp; + CF2_Fixed downMoveUp = ( fracDown == 0 ) + ? 0 + : cf2_intToFixed( 1 ) - fracDown; + CF2_Fixed upMoveUp = ( fracUp == 0 ) + ? 0 + : cf2_intToFixed( 1 ) - fracUp; + + /* smallest move up */ + CF2_Fixed moveUp = FT_MIN( downMoveUp, upMoveUp ); + /* smallest move down */ + CF2_Fixed moveDown = FT_MAX( downMoveDown, upMoveDown ); + + /* final amount to move edge or edge pair */ + CF2_Fixed move; + + CF2_Fixed downMinCounter = CF2_MIN_COUNTER; + CF2_Fixed upMinCounter = CF2_MIN_COUNTER; + FT_Bool saveEdge = FALSE; + + + /* minimum counter constraint doesn't apply when adjacent edges */ + /* are synthetic */ + /* TODO: doesn't seem a big effect; for now, reduce the code */ +#if 0 + if ( i == 0 || + cf2_hint_isSynthetic( &hintmap->edge[i - 1] ) ) + downMinCounter = 0; + + if ( j >= hintmap->count - 1 || + cf2_hint_isSynthetic( &hintmap->edge[j + 1] ) ) + upMinCounter = 0; +#endif + + /* is there room to move up? */ + /* there is if we are at top of array or the next edge is at or */ + /* beyond proposed move up? */ + if ( j >= hintmap->count - 1 || + hintmap->edge[j + 1].dsCoord >= + ADD_INT32( hintmap->edge[j].dsCoord, + moveUp + upMinCounter ) ) + { + /* there is room to move up; is there also room to move down? */ + if ( i == 0 || + hintmap->edge[i - 1].dsCoord <= + ADD_INT32( hintmap->edge[i].dsCoord, + moveDown - downMinCounter ) ) + { + /* move smaller absolute amount */ + move = ( -moveDown < moveUp ) ? moveDown : moveUp; /* optimum */ + } + else + move = moveUp; + } + else + { + /* is there room to move down? */ + if ( i == 0 || + hintmap->edge[i - 1].dsCoord <= + ADD_INT32( hintmap->edge[i].dsCoord, + moveDown - downMinCounter ) ) + { + move = moveDown; + /* true if non-optimum move */ + saveEdge = (FT_Bool)( moveUp < -moveDown ); + } + else + { + /* no room to move either way without overlapping or reducing */ + /* the counter too much */ + move = 0; + saveEdge = TRUE; + } + } + + /* Identify non-moves and moves down that aren't optimal, and save */ + /* them for second pass. */ + /* Do this only if there is an unlocked edge above (which could */ + /* possibly move). */ + if ( saveEdge && + j < hintmap->count - 1 && + !cf2_hint_isLocked( &hintmap->edge[j + 1] ) ) + { + CF2_HintMoveRec savedMove; + + + savedMove.j = j; + /* desired adjustment in second pass */ + savedMove.moveUp = moveUp - move; + + cf2_arrstack_push( hintmap->hintMoves, &savedMove ); + } + + /* move the edge(s) */ + hintmap->edge[i].dsCoord = ADD_INT32( hintmap->edge[i].dsCoord, + move ); + if ( isPair ) + hintmap->edge[j].dsCoord = ADD_INT32( hintmap->edge[j].dsCoord, + move ); + } + + /* assert there are no overlaps in device space */ + FT_ASSERT( i == 0 || + hintmap->edge[i - 1].dsCoord <= hintmap->edge[i].dsCoord ); + FT_ASSERT( i < j || + hintmap->edge[i].dsCoord <= hintmap->edge[j].dsCoord ); + + /* adjust the scales, avoiding divide by zero */ + if ( i > 0 ) + { + if ( hintmap->edge[i].csCoord != hintmap->edge[i - 1].csCoord ) + hintmap->edge[i - 1].scale = + FT_DivFix( SUB_INT32( hintmap->edge[i].dsCoord, + hintmap->edge[i - 1].dsCoord ), + SUB_INT32( hintmap->edge[i].csCoord, + hintmap->edge[i - 1].csCoord ) ); + } + + if ( isPair ) + { + if ( hintmap->edge[j].csCoord != hintmap->edge[j - 1].csCoord ) + hintmap->edge[j - 1].scale = + FT_DivFix( SUB_INT32( hintmap->edge[j].dsCoord, + hintmap->edge[j - 1].dsCoord ), + SUB_INT32( hintmap->edge[j].csCoord, + hintmap->edge[j - 1].csCoord ) ); + + i += 1; /* skip upper edge on next loop */ + } + } + + /* second pass tries to move non-optimal hints up, in case there is */ + /* room now */ + for ( i = cf2_arrstack_size( hintmap->hintMoves ); i > 0; i-- ) + { + CF2_HintMove hintMove = (CF2_HintMove) + cf2_arrstack_getPointer( hintmap->hintMoves, i - 1 ); + + + j = hintMove->j; + + /* this was tested before the push, above */ + FT_ASSERT( j < hintmap->count - 1 ); + + /* is there room to move up? */ + if ( hintmap->edge[j + 1].dsCoord >= + ADD_INT32( hintmap->edge[j].dsCoord, + hintMove->moveUp + CF2_MIN_COUNTER ) ) + { + /* there is more room now, move edge up */ + hintmap->edge[j].dsCoord = ADD_INT32( hintmap->edge[j].dsCoord, + hintMove->moveUp ); + + if ( cf2_hint_isPair( &hintmap->edge[j] ) ) + { + FT_ASSERT( j > 0 ); + hintmap->edge[j - 1].dsCoord = + ADD_INT32( hintmap->edge[j - 1].dsCoord, hintMove->moveUp ); + } + } + } + } + + + /* insert hint edges into map, sorted by csCoord */ + static void + cf2_hintmap_insertHint( CF2_HintMap hintmap, + CF2_Hint bottomHintEdge, + CF2_Hint topHintEdge ) + { + CF2_UInt indexInsert; + + /* set default values, then check for edge hints */ + FT_Bool isPair = TRUE; + CF2_Hint firstHintEdge = bottomHintEdge; + CF2_Hint secondHintEdge = topHintEdge; + + + /* one or none of the input params may be invalid when dealing with */ + /* edge hints; at least one edge must be valid */ + FT_ASSERT( cf2_hint_isValid( bottomHintEdge ) || + cf2_hint_isValid( topHintEdge ) ); + + /* determine how many and which edges to insert */ + if ( !cf2_hint_isValid( bottomHintEdge ) ) + { + /* insert only the top edge */ + firstHintEdge = topHintEdge; + isPair = FALSE; + } + else if ( !cf2_hint_isValid( topHintEdge ) ) + { + /* insert only the bottom edge */ + isPair = FALSE; + } + + /* paired edges must be in proper order */ + if ( isPair && + topHintEdge->csCoord < bottomHintEdge->csCoord ) + return; + + /* linear search to find index value of insertion point */ + indexInsert = 0; + for ( ; indexInsert < hintmap->count; indexInsert++ ) + { + if ( hintmap->edge[indexInsert].csCoord >= firstHintEdge->csCoord ) + break; + } + + FT_TRACE7(( " Got hint at %.2f (%.2f)\n", + firstHintEdge->csCoord / 65536.0, + firstHintEdge->dsCoord / 65536.0 )); + if ( isPair ) + FT_TRACE7(( " Got hint at %.2f (%.2f)\n", + secondHintEdge->csCoord / 65536.0, + secondHintEdge->dsCoord / 65536.0 )); + + /* + * Discard any hints that overlap in character space. Most often, this + * is while building the initial map, where captured hints from all + * zones are combined. Define overlap to include hints that `touch' + * (overlap zero). Hiragino Sans/Gothic fonts have numerous hints that + * touch. Some fonts have non-ideographic glyphs that overlap our + * synthetic hints. + * + * Overlap also occurs when darkening stem hints that are close. + * + */ + if ( indexInsert < hintmap->count ) + { + /* we are inserting before an existing edge: */ + /* verify that an existing edge is not the same */ + if ( hintmap->edge[indexInsert].csCoord == firstHintEdge->csCoord ) + return; /* ignore overlapping stem hint */ + + /* verify that a new pair does not straddle the next edge */ + if ( isPair && + hintmap->edge[indexInsert].csCoord <= secondHintEdge->csCoord ) + return; /* ignore overlapping stem hint */ + + /* verify that we are not inserting between paired edges */ + if ( cf2_hint_isPairTop( &hintmap->edge[indexInsert] ) ) + return; /* ignore overlapping stem hint */ + } + + /* recompute device space locations using initial hint map */ + if ( cf2_hintmap_isValid( hintmap->initialHintMap ) && + !cf2_hint_isLocked( firstHintEdge ) ) + { + if ( isPair ) + { + /* Use hint map to position the center of stem, and nominal scale */ + /* to position the two edges. This preserves the stem width. */ + CF2_Fixed midpoint = + cf2_hintmap_map( + hintmap->initialHintMap, + ADD_INT32( secondHintEdge->csCoord, + firstHintEdge->csCoord ) / 2 ); + CF2_Fixed halfWidth = + FT_MulFix( SUB_INT32( secondHintEdge->csCoord, + firstHintEdge->csCoord ) / 2, + hintmap->scale ); + + + firstHintEdge->dsCoord = SUB_INT32( midpoint, halfWidth ); + secondHintEdge->dsCoord = ADD_INT32( midpoint, halfWidth ); + } + else + firstHintEdge->dsCoord = cf2_hintmap_map( hintmap->initialHintMap, + firstHintEdge->csCoord ); + } + + /* + * Discard any hints that overlap in device space; this can occur + * because locked hints have been moved to align with blue zones. + * + * TODO: Although we might correct this later during adjustment, we + * don't currently have a way to delete a conflicting hint once it has + * been inserted. See v2.030 MinionPro-Regular, 12 ppem darkened, + * initial hint map for second path, glyph 945 (the perispomeni (tilde) + * in U+1F6E, Greek omega with psili and perispomeni). Darkening is + * 25. Pair 667,747 initially conflicts in design space with top edge + * 660. This is because 667 maps to 7.87, and the top edge was + * captured by a zone at 8.0. The pair is later successfully inserted + * in a zone without the top edge. In this zone it is adjusted to 8.0, + * and no longer conflicts with the top edge in design space. This + * means it can be included in yet a later zone which does have the top + * edge hint. This produces a small mismatch between the first and + * last points of this path, even though the hint masks are the same. + * The density map difference is tiny (1/256). + * + */ + + if ( indexInsert > 0 ) + { + /* we are inserting after an existing edge */ + if ( firstHintEdge->dsCoord < hintmap->edge[indexInsert - 1].dsCoord ) + return; + } + + if ( indexInsert < hintmap->count ) + { + /* we are inserting before an existing edge */ + if ( isPair ) + { + if ( secondHintEdge->dsCoord > hintmap->edge[indexInsert].dsCoord ) + return; + } + else + { + if ( firstHintEdge->dsCoord > hintmap->edge[indexInsert].dsCoord ) + return; + } + } + + /* make room to insert */ + { + CF2_UInt iSrc = hintmap->count - 1; + CF2_UInt iDst = isPair ? hintmap->count + 1 : hintmap->count; + + CF2_UInt count = hintmap->count - indexInsert; + + + if ( iDst >= CF2_MAX_HINT_EDGES ) + { + FT_TRACE4(( "cf2_hintmap_insertHint: too many hintmaps\n" )); + return; + } + + while ( count-- ) + hintmap->edge[iDst--] = hintmap->edge[iSrc--]; + + /* insert first edge */ + hintmap->edge[indexInsert] = *firstHintEdge; /* copy struct */ + hintmap->count += 1; + + FT_TRACE7(( " Inserting hint %.2f (%.2f)\n", + firstHintEdge->csCoord / 65536.0, + firstHintEdge->dsCoord / 65536.0 )); + + if ( isPair ) + { + /* insert second edge */ + hintmap->edge[indexInsert + 1] = *secondHintEdge; /* copy struct */ + hintmap->count += 1; + + FT_TRACE7(( " Inserting hint %.2f (%.2f)\n", + secondHintEdge->csCoord / 65536.0, + secondHintEdge->dsCoord / 65536.0 )); + + } + } + + return; + } + + + /* + * Build a map from hints and mask. + * + * This function may recur one level if `hintmap->initialHintMap' is not yet + * valid. + * If `initialMap' is true, simply build initial map. + * + * Synthetic hints are used in two ways. A hint at zero is inserted, if + * needed, in the initial hint map, to prevent translations from + * propagating across the origin. If synthetic em box hints are enabled + * for ideographic dictionaries, then they are inserted in all hint + * maps, including the initial one. + * + */ + FT_LOCAL_DEF( void ) + cf2_hintmap_build( CF2_HintMap hintmap, + CF2_ArrStack hStemHintArray, + CF2_ArrStack vStemHintArray, + CF2_HintMask hintMask, + CF2_Fixed hintOrigin, + FT_Bool initialMap ) + { + FT_Byte* maskPtr; + + CF2_Font font = hintmap->font; + CF2_HintMaskRec tempHintMask; + + size_t bitCount, i; + FT_Byte maskByte; + + + /* check whether initial map is constructed */ + if ( !initialMap && !cf2_hintmap_isValid( hintmap->initialHintMap ) ) + { + /* make recursive call with initialHintMap and temporary mask; */ + /* temporary mask will get all bits set, below */ + cf2_hintmask_init( &tempHintMask, hintMask->error ); + cf2_hintmap_build( hintmap->initialHintMap, + hStemHintArray, + vStemHintArray, + &tempHintMask, + hintOrigin, + TRUE ); + } + + if ( !cf2_hintmask_isValid( hintMask ) ) + { + /* without a hint mask, assume all hints are active */ + cf2_hintmask_setAll( hintMask, + cf2_arrstack_size( hStemHintArray ) + + cf2_arrstack_size( vStemHintArray ) ); + if ( !cf2_hintmask_isValid( hintMask ) ) + { + if ( font->isT1 ) + { + /* no error, just continue unhinted */ + *hintMask->error = FT_Err_Ok; + hintmap->hinted = FALSE; + } + return; /* too many stem hints */ + } + } + + /* begin by clearing the map */ + hintmap->count = 0; + hintmap->lastIndex = 0; + + /* make a copy of the hint mask so we can modify it */ + tempHintMask = *hintMask; + maskPtr = cf2_hintmask_getMaskPtr( &tempHintMask ); + + /* use the hStem hints only, which are first in the mask */ + bitCount = cf2_arrstack_size( hStemHintArray ); + + /* Defense-in-depth. Should never return here. */ + if ( bitCount > hintMask->bitCount ) + return; + + /* synthetic embox hints get highest priority */ + if ( font->blues.doEmBoxHints ) + { + CF2_HintRec dummy; + + + cf2_hint_initZero( &dummy ); /* invalid hint map element */ + + /* ghost bottom */ + cf2_hintmap_insertHint( hintmap, + &font->blues.emBoxBottomEdge, + &dummy ); + /* ghost top */ + cf2_hintmap_insertHint( hintmap, + &dummy, + &font->blues.emBoxTopEdge ); + } + + /* insert hints captured by a blue zone or already locked (higher */ + /* priority) */ + for ( i = 0, maskByte = 0x80; i < bitCount; i++ ) + { + if ( maskByte & *maskPtr ) + { + /* expand StemHint into two `CF2_Hint' elements */ + CF2_HintRec bottomHintEdge, topHintEdge; + + + cf2_hint_init( &bottomHintEdge, + hStemHintArray, + i, + font, + hintOrigin, + hintmap->scale, + TRUE /* bottom */ ); + cf2_hint_init( &topHintEdge, + hStemHintArray, + i, + font, + hintOrigin, + hintmap->scale, + FALSE /* top */ ); + + if ( cf2_hint_isLocked( &bottomHintEdge ) || + cf2_hint_isLocked( &topHintEdge ) || + cf2_blues_capture( &font->blues, + &bottomHintEdge, + &topHintEdge ) ) + { + /* insert captured hint into map */ + cf2_hintmap_insertHint( hintmap, &bottomHintEdge, &topHintEdge ); + + *maskPtr &= ~maskByte; /* turn off the bit for this hint */ + } + } + + if ( ( i & 7 ) == 7 ) + { + /* move to next mask byte */ + maskPtr++; + maskByte = 0x80; + } + else + maskByte >>= 1; + } + + /* initial hint map includes only captured hints plus maybe one at 0 */ + + /* + * TODO: There is a problem here because we are trying to build a + * single hint map containing all captured hints. It is + * possible for there to be conflicts between captured hints, + * either because of darkening or because the hints are in + * separate hint zones (we are ignoring hint zones for the + * initial map). An example of the latter is MinionPro-Regular + * v2.030 glyph 883 (Greek Capital Alpha with Psili) at 15ppem. + * A stem hint for the psili conflicts with the top edge hint + * for the base character. The stem hint gets priority because + * of its sort order. In glyph 884 (Greek Capital Alpha with + * Psili and Oxia), the top of the base character gets a stem + * hint, and the psili does not. This creates different initial + * maps for the two glyphs resulting in different renderings of + * the base character. Will probably defer this either as not + * worth the cost or as a font bug. I don't think there is any + * good reason for an accent to be captured by an alignment + * zone. -darnold 2/12/10 + */ + + if ( initialMap ) + { + /* Apply a heuristic that inserts a point for (0,0), unless it's */ + /* already covered by a mapping. This locks the baseline for glyphs */ + /* that have no baseline hints. */ + + if ( hintmap->count == 0 || + hintmap->edge[0].csCoord > 0 || + hintmap->edge[hintmap->count - 1].csCoord < 0 ) + { + /* all edges are above 0 or all edges are below 0; */ + /* construct a locked edge hint at 0 */ + + CF2_HintRec edge, invalid; + + + cf2_hint_initZero( &edge ); + + edge.flags = CF2_GhostBottom | + CF2_Locked | + CF2_Synthetic; + edge.scale = hintmap->scale; + + cf2_hint_initZero( &invalid ); + cf2_hintmap_insertHint( hintmap, &edge, &invalid ); + } + } + else + { + /* insert remaining hints */ + + maskPtr = cf2_hintmask_getMaskPtr( &tempHintMask ); + + for ( i = 0, maskByte = 0x80; i < bitCount; i++ ) + { + if ( maskByte & *maskPtr ) + { + CF2_HintRec bottomHintEdge, topHintEdge; + + + cf2_hint_init( &bottomHintEdge, + hStemHintArray, + i, + font, + hintOrigin, + hintmap->scale, + TRUE /* bottom */ ); + cf2_hint_init( &topHintEdge, + hStemHintArray, + i, + font, + hintOrigin, + hintmap->scale, + FALSE /* top */ ); + + cf2_hintmap_insertHint( hintmap, &bottomHintEdge, &topHintEdge ); + } + + if ( ( i & 7 ) == 7 ) + { + /* move to next mask byte */ + maskPtr++; + maskByte = 0x80; + } + else + maskByte >>= 1; + } + } + + FT_TRACE6(( initialMap ? "flags: [p]air [g]host [t]op " + "[b]ottom [L]ocked [S]ynthetic\n" + "Initial hintmap\n" + : "Hints:\n" )); + cf2_hintmap_dump( hintmap ); + + /* + * Note: The following line is a convenient place to break when + * debugging hinting. Examine `hintmap->edge' for the list of + * enabled hints, then step over the call to see the effect of + * adjustment. We stop here first on the recursive call that + * creates the initial map, and then on each counter group and + * hint zone. + */ + + /* adjust positions of hint edges that are not locked to blue zones */ + cf2_hintmap_adjustHints( hintmap ); + + FT_TRACE6(( "(adjusted)\n" )); + cf2_hintmap_dump( hintmap ); + + /* save the position of all hints that were used in this hint map; */ + /* if we use them again, we'll locate them in the same position */ + if ( !initialMap ) + { + for ( i = 0; i < hintmap->count; i++ ) + { + if ( !cf2_hint_isSynthetic( &hintmap->edge[i] ) ) + { + /* Note: include both valid and invalid edges */ + /* Note: top and bottom edges are copied back separately */ + CF2_StemHint stemhint = (CF2_StemHint) + cf2_arrstack_getPointer( hStemHintArray, + hintmap->edge[i].index ); + + + if ( cf2_hint_isTop( &hintmap->edge[i] ) ) + stemhint->maxDS = hintmap->edge[i].dsCoord; + else + stemhint->minDS = hintmap->edge[i].dsCoord; + + stemhint->used = TRUE; + } + } + } + + /* hint map is ready to use */ + hintmap->isValid = TRUE; + + /* remember this mask has been used */ + cf2_hintmask_setNew( hintMask, FALSE ); + } + + + FT_LOCAL_DEF( void ) + cf2_glyphpath_init( CF2_GlyphPath glyphpath, + CF2_Font font, + CF2_OutlineCallbacks callbacks, + CF2_Fixed scaleY, + /* CF2_Fixed hShift, */ + CF2_ArrStack hStemHintArray, + CF2_ArrStack vStemHintArray, + CF2_HintMask hintMask, + CF2_Fixed hintOriginY, + const CF2_Blues blues, + const FT_Vector* fractionalTranslation ) + { + FT_ZERO( glyphpath ); + + glyphpath->font = font; + glyphpath->callbacks = callbacks; + + cf2_arrstack_init( &glyphpath->hintMoves, + font->memory, + &font->error, + sizeof ( CF2_HintMoveRec ) ); + + cf2_hintmap_init( &glyphpath->initialHintMap, + font, + &glyphpath->initialHintMap, + &glyphpath->hintMoves, + scaleY ); + cf2_hintmap_init( &glyphpath->firstHintMap, + font, + &glyphpath->initialHintMap, + &glyphpath->hintMoves, + scaleY ); + cf2_hintmap_init( &glyphpath->hintMap, + font, + &glyphpath->initialHintMap, + &glyphpath->hintMoves, + scaleY ); + + glyphpath->scaleX = font->innerTransform.a; + glyphpath->scaleC = font->innerTransform.c; + glyphpath->scaleY = font->innerTransform.d; + + glyphpath->fractionalTranslation = *fractionalTranslation; + +#if 0 + glyphpath->hShift = hShift; /* for fauxing */ +#endif + + glyphpath->hStemHintArray = hStemHintArray; + glyphpath->vStemHintArray = vStemHintArray; + glyphpath->hintMask = hintMask; /* ptr to current mask */ + glyphpath->hintOriginY = hintOriginY; + glyphpath->blues = blues; + glyphpath->darken = font->darkened; /* TODO: should we make copies? */ + glyphpath->xOffset = font->darkenX; + glyphpath->yOffset = font->darkenY; + glyphpath->miterLimit = 2 * FT_MAX( + cf2_fixedAbs( glyphpath->xOffset ), + cf2_fixedAbs( glyphpath->yOffset ) ); + + /* .1 character space unit */ + glyphpath->snapThreshold = cf2_doubleToFixed( 0.1 ); + + glyphpath->moveIsPending = TRUE; + glyphpath->pathIsOpen = FALSE; + glyphpath->pathIsClosing = FALSE; + glyphpath->elemIsQueued = FALSE; + } + + + FT_LOCAL_DEF( void ) + cf2_glyphpath_finalize( CF2_GlyphPath glyphpath ) + { + cf2_arrstack_finalize( &glyphpath->hintMoves ); + } + + + /* + * Hint point in y-direction and apply outerTransform. + * Input `current' hint map (which is actually delayed by one element). + * Input x,y point in Character Space. + * Output x,y point in Device Space, including translation. + */ + static void + cf2_glyphpath_hintPoint( CF2_GlyphPath glyphpath, + CF2_HintMap hintmap, + FT_Vector* ppt, + CF2_Fixed x, + CF2_Fixed y ) + { + FT_Vector pt; /* hinted point in upright DS */ + + + pt.x = ADD_INT32( FT_MulFix( glyphpath->scaleX, x ), + FT_MulFix( glyphpath->scaleC, y ) ); + pt.y = cf2_hintmap_map( hintmap, y ); + + ppt->x = ADD_INT32( + FT_MulFix( glyphpath->font->outerTransform.a, pt.x ), + ADD_INT32( + FT_MulFix( glyphpath->font->outerTransform.c, pt.y ), + glyphpath->fractionalTranslation.x ) ); + ppt->y = ADD_INT32( + FT_MulFix( glyphpath->font->outerTransform.b, pt.x ), + ADD_INT32( + FT_MulFix( glyphpath->font->outerTransform.d, pt.y ), + glyphpath->fractionalTranslation.y ) ); + } + + + /* + * From two line segments, (u1,u2) and (v1,v2), compute a point of + * intersection on the corresponding lines. + * Return false if no intersection is found, or if the intersection is + * too far away from the ends of the line segments, u2 and v1. + * + */ + static FT_Bool + cf2_glyphpath_computeIntersection( CF2_GlyphPath glyphpath, + const FT_Vector* u1, + const FT_Vector* u2, + const FT_Vector* v1, + const FT_Vector* v2, + FT_Vector* intersection ) + { + /* + * Let `u' be a zero-based vector from the first segment, `v' from the + * second segment. + * Let `w 'be the zero-based vector from `u1' to `v1'. + * `perp' is the `perpendicular dot product'; see + * https://mathworld.wolfram.com/PerpDotProduct.html. + * `s' is the parameter for the parametric line for the first segment + * (`u'). + * + * See notation in + * http://softsurfer.com/Archive/algorithm_0104/algorithm_0104B.htm. + * Calculations are done in 16.16, but must handle the squaring of + * line lengths in character space. We scale all vectors by 1/32 to + * avoid overflow. This allows values up to 4095 to be squared. The + * scale factor cancels in the divide. + * + * TODO: the scale factor could be computed from UnitsPerEm. + * + */ + +#define cf2_perp( a, b ) \ + ( FT_MulFix( a.x, b.y ) - FT_MulFix( a.y, b.x ) ) + + /* round and divide by 32 */ +#define CF2_CS_SCALE( x ) \ + ( ( (x) + 0x10 ) >> 5 ) + + FT_Vector u, v, w; /* scaled vectors */ + CF2_Fixed denominator, s; + + + u.x = CF2_CS_SCALE( SUB_INT32( u2->x, u1->x ) ); + u.y = CF2_CS_SCALE( SUB_INT32( u2->y, u1->y ) ); + v.x = CF2_CS_SCALE( SUB_INT32( v2->x, v1->x ) ); + v.y = CF2_CS_SCALE( SUB_INT32( v2->y, v1->y ) ); + w.x = CF2_CS_SCALE( SUB_INT32( v1->x, u1->x ) ); + w.y = CF2_CS_SCALE( SUB_INT32( v1->y, u1->y ) ); + + denominator = cf2_perp( u, v ); + + if ( denominator == 0 ) + return FALSE; /* parallel or coincident lines */ + + s = FT_DivFix( cf2_perp( w, v ), denominator ); + + intersection->x = ADD_INT32( u1->x, + FT_MulFix( s, SUB_INT32( u2->x, u1->x ) ) ); + intersection->y = ADD_INT32( u1->y, + FT_MulFix( s, SUB_INT32( u2->y, u1->y ) ) ); + + + /* + * Special case snapping for horizontal and vertical lines. + * This cleans up intersections and reduces problems with winding + * order detection. + * Sample case is sbc cd KozGoPr6N-Medium.otf 20 16685. + * Note: these calculations are in character space. + * + */ + + if ( u1->x == u2->x && + cf2_fixedAbs( SUB_INT32( intersection->x, + u1->x ) ) < glyphpath->snapThreshold ) + intersection->x = u1->x; + if ( u1->y == u2->y && + cf2_fixedAbs( SUB_INT32( intersection->y, + u1->y ) ) < glyphpath->snapThreshold ) + intersection->y = u1->y; + + if ( v1->x == v2->x && + cf2_fixedAbs( SUB_INT32( intersection->x, + v1->x ) ) < glyphpath->snapThreshold ) + intersection->x = v1->x; + if ( v1->y == v2->y && + cf2_fixedAbs( SUB_INT32( intersection->y, + v1->y ) ) < glyphpath->snapThreshold ) + intersection->y = v1->y; + + /* limit the intersection distance from midpoint of u2 and v1 */ + if ( cf2_fixedAbs( intersection->x - ADD_INT32( u2->x, v1->x ) / 2 ) > + glyphpath->miterLimit || + cf2_fixedAbs( intersection->y - ADD_INT32( u2->y, v1->y ) / 2 ) > + glyphpath->miterLimit ) + return FALSE; + + return TRUE; + } + + + /* + * Push the cached element (glyphpath->prevElem*) to the outline + * consumer. When a darkening offset is used, the end point of the + * cached element may be adjusted to an intersection point or we may + * synthesize a connecting line to the current element. If we are + * closing a subpath, we may also generate a connecting line to the start + * point. + * + * This is where Character Space (CS) is converted to Device Space (DS) + * using a hint map. This calculation must use a HintMap that was valid + * at the time the element was saved. For the first point in a subpath, + * that is a saved HintMap. For most elements, it just means the caller + * has delayed building a HintMap from the current HintMask. + * + * Transform each point with outerTransform and call the outline + * callbacks. This is a general 3x3 transform: + * + * x' = a*x + c*y + tx, y' = b*x + d*y + ty + * + * but it uses 4 elements from CF2_Font and the translation part + * from CF2_GlyphPath. + * + */ + static void + cf2_glyphpath_pushPrevElem( CF2_GlyphPath glyphpath, + CF2_HintMap hintmap, + FT_Vector* nextP0, + FT_Vector nextP1, + FT_Bool close ) + { + CF2_CallbackParamsRec params; + + FT_Vector* prevP0; + FT_Vector* prevP1; + + FT_Vector intersection = { 0, 0 }; + FT_Bool useIntersection = FALSE; + + + FT_ASSERT( glyphpath->prevElemOp == CF2_PathOpLineTo || + glyphpath->prevElemOp == CF2_PathOpCubeTo ); + + if ( glyphpath->prevElemOp == CF2_PathOpLineTo ) + { + prevP0 = &glyphpath->prevElemP0; + prevP1 = &glyphpath->prevElemP1; + } + else + { + prevP0 = &glyphpath->prevElemP2; + prevP1 = &glyphpath->prevElemP3; + } + + /* optimization: if previous and next elements are offset by the same */ + /* amount, then there will be no gap, and no need to compute an */ + /* intersection. */ + if ( prevP1->x != nextP0->x || prevP1->y != nextP0->y ) + { + /* previous element does not join next element: */ + /* adjust end point of previous element to the intersection */ + useIntersection = cf2_glyphpath_computeIntersection( glyphpath, + prevP0, + prevP1, + nextP0, + &nextP1, + &intersection ); + if ( useIntersection ) + { + /* modify the last point of the cached element (either line or */ + /* curve) */ + *prevP1 = intersection; + } + } + + params.pt0 = glyphpath->currentDS; + + switch( glyphpath->prevElemOp ) + { + case CF2_PathOpLineTo: + params.op = CF2_PathOpLineTo; + + /* note: pt2 and pt3 are unused */ + + if ( close ) + { + /* use first hint map if closing */ + cf2_glyphpath_hintPoint( glyphpath, + &glyphpath->firstHintMap, + ¶ms.pt1, + glyphpath->prevElemP1.x, + glyphpath->prevElemP1.y ); + } + else + { + cf2_glyphpath_hintPoint( glyphpath, + hintmap, + ¶ms.pt1, + glyphpath->prevElemP1.x, + glyphpath->prevElemP1.y ); + } + + /* output only non-zero length lines */ + if ( params.pt0.x != params.pt1.x || params.pt0.y != params.pt1.y ) + { + glyphpath->callbacks->lineTo( glyphpath->callbacks, ¶ms ); + + glyphpath->currentDS = params.pt1; + } + break; + + case CF2_PathOpCubeTo: + params.op = CF2_PathOpCubeTo; + + /* TODO: should we intersect the interior joins (p1-p2 and p2-p3)? */ + cf2_glyphpath_hintPoint( glyphpath, + hintmap, + ¶ms.pt1, + glyphpath->prevElemP1.x, + glyphpath->prevElemP1.y ); + cf2_glyphpath_hintPoint( glyphpath, + hintmap, + ¶ms.pt2, + glyphpath->prevElemP2.x, + glyphpath->prevElemP2.y ); + cf2_glyphpath_hintPoint( glyphpath, + hintmap, + ¶ms.pt3, + glyphpath->prevElemP3.x, + glyphpath->prevElemP3.y ); + + glyphpath->callbacks->cubeTo( glyphpath->callbacks, ¶ms ); + + glyphpath->currentDS = params.pt3; + + break; + } + + if ( !useIntersection || close ) + { + /* insert connecting line between end of previous element and start */ + /* of current one */ + /* note: at the end of a subpath, we might do both, so use `nextP0' */ + /* before we change it, below */ + + if ( close ) + { + /* if we are closing the subpath, then nextP0 is in the first */ + /* hint zone */ + cf2_glyphpath_hintPoint( glyphpath, + &glyphpath->firstHintMap, + ¶ms.pt1, + nextP0->x, + nextP0->y ); + } + else + { + cf2_glyphpath_hintPoint( glyphpath, + hintmap, + ¶ms.pt1, + nextP0->x, + nextP0->y ); + } + + if ( params.pt1.x != glyphpath->currentDS.x || + params.pt1.y != glyphpath->currentDS.y ) + { + /* length is nonzero */ + params.op = CF2_PathOpLineTo; + params.pt0 = glyphpath->currentDS; + + /* note: pt2 and pt3 are unused */ + glyphpath->callbacks->lineTo( glyphpath->callbacks, ¶ms ); + + glyphpath->currentDS = params.pt1; + } + } + + if ( useIntersection ) + { + /* return intersection point to caller */ + *nextP0 = intersection; + } + } + + + /* push a MoveTo element based on current point and offset of current */ + /* element */ + static void + cf2_glyphpath_pushMove( CF2_GlyphPath glyphpath, + FT_Vector start ) + { + CF2_CallbackParamsRec params; + + + params.op = CF2_PathOpMoveTo; + params.pt0 = glyphpath->currentDS; + + /* Test if move has really happened yet; it would have called */ + /* `cf2_hintmap_build' to set `isValid'. */ + if ( !cf2_hintmap_isValid( &glyphpath->hintMap ) ) + { + /* we are here iff first subpath is missing a moveto operator: */ + /* synthesize first moveTo to finish initialization of hintMap */ + cf2_glyphpath_moveTo( glyphpath, + glyphpath->start.x, + glyphpath->start.y ); + } + + cf2_glyphpath_hintPoint( glyphpath, + &glyphpath->hintMap, + ¶ms.pt1, + start.x, + start.y ); + + /* note: pt2 and pt3 are unused */ + glyphpath->callbacks->moveTo( glyphpath->callbacks, ¶ms ); + + glyphpath->currentDS = params.pt1; + glyphpath->offsetStart0 = start; + } + + + /* + * All coordinates are in character space. + * On input, (x1, y1) and (x2, y2) give line segment. + * On output, (x, y) give offset vector. + * We use a piecewise approximation to trig functions. + * + * TODO: Offset true perpendicular and proper length + * supply the y-translation for hinting here, too, + * that adds yOffset unconditionally to *y. + */ + static void + cf2_glyphpath_computeOffset( CF2_GlyphPath glyphpath, + CF2_Fixed x1, + CF2_Fixed y1, + CF2_Fixed x2, + CF2_Fixed y2, + CF2_Fixed* x, + CF2_Fixed* y ) + { + CF2_Fixed dx = SUB_INT32( x2, x1 ); + CF2_Fixed dy = SUB_INT32( y2, y1 ); + + + /* note: negative offsets don't work here; negate deltas to change */ + /* quadrants, below */ + if ( glyphpath->font->reverseWinding ) + { + dx = NEG_INT32( dx ); + dy = NEG_INT32( dy ); + } + + *x = *y = 0; + + if ( !glyphpath->darken ) + return; + + /* add momentum for this path element */ + glyphpath->callbacks->windingMomentum = + ADD_INT32( glyphpath->callbacks->windingMomentum, + cf2_getWindingMomentum( x1, y1, x2, y2 ) ); + + /* note: allow mixed integer and fixed multiplication here */ + if ( dx >= 0 ) + { + if ( dy >= 0 ) + { + /* first quadrant, +x +y */ + + if ( dx > MUL_INT32( 2, dy ) ) + { + /* +x */ + *x = 0; + *y = 0; + } + else if ( dy > MUL_INT32( 2, dx ) ) + { + /* +y */ + *x = glyphpath->xOffset; + *y = glyphpath->yOffset; + } + else + { + /* +x +y */ + *x = FT_MulFix( cf2_doubleToFixed( 0.7 ), + glyphpath->xOffset ); + *y = FT_MulFix( cf2_doubleToFixed( 1.0 - 0.7 ), + glyphpath->yOffset ); + } + } + else + { + /* fourth quadrant, +x -y */ + + if ( dx > MUL_INT32( -2, dy ) ) + { + /* +x */ + *x = 0; + *y = 0; + } + else if ( NEG_INT32( dy ) > MUL_INT32( 2, dx ) ) + { + /* -y */ + *x = NEG_INT32( glyphpath->xOffset ); + *y = glyphpath->yOffset; + } + else + { + /* +x -y */ + *x = FT_MulFix( cf2_doubleToFixed( -0.7 ), + glyphpath->xOffset ); + *y = FT_MulFix( cf2_doubleToFixed( 1.0 - 0.7 ), + glyphpath->yOffset ); + } + } + } + else + { + if ( dy >= 0 ) + { + /* second quadrant, -x +y */ + + if ( NEG_INT32( dx ) > MUL_INT32( 2, dy ) ) + { + /* -x */ + *x = 0; + *y = MUL_INT32( 2, glyphpath->yOffset ); + } + else if ( dy > MUL_INT32( -2, dx ) ) + { + /* +y */ + *x = glyphpath->xOffset; + *y = glyphpath->yOffset; + } + else + { + /* -x +y */ + *x = FT_MulFix( cf2_doubleToFixed( 0.7 ), + glyphpath->xOffset ); + *y = FT_MulFix( cf2_doubleToFixed( 1.0 + 0.7 ), + glyphpath->yOffset ); + } + } + else + { + /* third quadrant, -x -y */ + + if ( NEG_INT32( dx ) > MUL_INT32( -2, dy ) ) + { + /* -x */ + *x = 0; + *y = MUL_INT32( 2, glyphpath->yOffset ); + } + else if ( NEG_INT32( dy ) > MUL_INT32( -2, dx ) ) + { + /* -y */ + *x = NEG_INT32( glyphpath->xOffset ); + *y = glyphpath->yOffset; + } + else + { + /* -x -y */ + *x = FT_MulFix( cf2_doubleToFixed( -0.7 ), + glyphpath->xOffset ); + *y = FT_MulFix( cf2_doubleToFixed( 1.0 + 0.7 ), + glyphpath->yOffset ); + } + } + } + } + + + /* + * The functions cf2_glyphpath_{moveTo,lineTo,curveTo,closeOpenPath} are + * called by the interpreter with Character Space (CS) coordinates. Each + * path element is placed into a queue of length one to await the + * calculation of the following element. At that time, the darkening + * offset of the following element is known and joins can be computed, + * including possible modification of this element, before mapping to + * Device Space (DS) and passing it on to the outline consumer. + * + */ + FT_LOCAL_DEF( void ) + cf2_glyphpath_moveTo( CF2_GlyphPath glyphpath, + CF2_Fixed x, + CF2_Fixed y ) + { + cf2_glyphpath_closeOpenPath( glyphpath ); + + /* save the parameters of the move for later, when we'll know how to */ + /* offset it; */ + /* also save last move point */ + glyphpath->currentCS.x = glyphpath->start.x = x; + glyphpath->currentCS.y = glyphpath->start.y = y; + + glyphpath->moveIsPending = TRUE; + + /* ensure we have a valid map with current mask */ + if ( !cf2_hintmap_isValid( &glyphpath->hintMap ) || + cf2_hintmask_isNew( glyphpath->hintMask ) ) + cf2_hintmap_build( &glyphpath->hintMap, + glyphpath->hStemHintArray, + glyphpath->vStemHintArray, + glyphpath->hintMask, + glyphpath->hintOriginY, + FALSE ); + + /* save a copy of current HintMap to use when drawing initial point */ + ft_memcpy(&glyphpath->firstHintMap, &glyphpath->hintMap, sizeof(glyphpath->hintMap)); + } + + + FT_LOCAL_DEF( void ) + cf2_glyphpath_lineTo( CF2_GlyphPath glyphpath, + CF2_Fixed x, + CF2_Fixed y ) + { + CF2_Fixed xOffset, yOffset; + FT_Vector P0, P1; + FT_Bool newHintMap; + + /* + * New hints will be applied after cf2_glyphpath_pushPrevElem has run. + * In case this is a synthesized closing line, any new hints should be + * delayed until this path is closed (`cf2_hintmask_isNew' will be + * called again before the next line or curve). + */ + + /* true if new hint map not on close */ + newHintMap = cf2_hintmask_isNew( glyphpath->hintMask ) && + !glyphpath->pathIsClosing; + + /* + * Zero-length lines may occur in the charstring. Because we cannot + * compute darkening offsets or intersections from zero-length lines, + * it is best to remove them and avoid artifacts. However, zero-length + * lines in CS at the start of a new hint map can generate non-zero + * lines in DS due to hint substitution. We detect a change in hint + * map here and pass those zero-length lines along. + */ + + /* + * Note: Find explicitly closed paths here with a conditional + * breakpoint using + * + * !gp->pathIsClosing && gp->start.x == x && gp->start.y == y + * + */ + + if ( glyphpath->currentCS.x == x && + glyphpath->currentCS.y == y && + !newHintMap ) + /* + * Ignore zero-length lines in CS where the hint map is the same + * because the line in DS will also be zero length. + * + * Ignore zero-length lines when we synthesize a closing line because + * the close will be handled in cf2_glyphPath_pushPrevElem. + */ + return; + + cf2_glyphpath_computeOffset( glyphpath, + glyphpath->currentCS.x, + glyphpath->currentCS.y, + x, + y, + &xOffset, + &yOffset ); + + /* construct offset points */ + P0.x = ADD_INT32( glyphpath->currentCS.x, xOffset ); + P0.y = ADD_INT32( glyphpath->currentCS.y, yOffset ); + P1.x = ADD_INT32( x, xOffset ); + P1.y = ADD_INT32( y, yOffset ); + + if ( glyphpath->moveIsPending ) + { + /* emit offset 1st point as MoveTo */ + cf2_glyphpath_pushMove( glyphpath, P0 ); + + glyphpath->moveIsPending = FALSE; /* adjust state machine */ + glyphpath->pathIsOpen = TRUE; + + glyphpath->offsetStart1 = P1; /* record second point */ + } + + if ( glyphpath->elemIsQueued ) + { + FT_ASSERT( cf2_hintmap_isValid( &glyphpath->hintMap ) || + glyphpath->hintMap.count == 0 ); + + cf2_glyphpath_pushPrevElem( glyphpath, + &glyphpath->hintMap, + &P0, + P1, + FALSE ); + } + + /* queue the current element with offset points */ + glyphpath->elemIsQueued = TRUE; + glyphpath->prevElemOp = CF2_PathOpLineTo; + glyphpath->prevElemP0 = P0; + glyphpath->prevElemP1 = P1; + + /* update current map */ + if ( newHintMap ) + cf2_hintmap_build( &glyphpath->hintMap, + glyphpath->hStemHintArray, + glyphpath->vStemHintArray, + glyphpath->hintMask, + glyphpath->hintOriginY, + FALSE ); + + glyphpath->currentCS.x = x; /* pre-offset current point */ + glyphpath->currentCS.y = y; + } + + + FT_LOCAL_DEF( void ) + cf2_glyphpath_curveTo( CF2_GlyphPath glyphpath, + CF2_Fixed x1, + CF2_Fixed y1, + CF2_Fixed x2, + CF2_Fixed y2, + CF2_Fixed x3, + CF2_Fixed y3 ) + { + CF2_Fixed xOffset1, yOffset1, xOffset3, yOffset3; + FT_Vector P0, P1, P2, P3; + + + /* TODO: ignore zero length portions of curve?? */ + cf2_glyphpath_computeOffset( glyphpath, + glyphpath->currentCS.x, + glyphpath->currentCS.y, + x1, + y1, + &xOffset1, + &yOffset1 ); + cf2_glyphpath_computeOffset( glyphpath, + x2, + y2, + x3, + y3, + &xOffset3, + &yOffset3 ); + + /* add momentum from the middle segment */ + glyphpath->callbacks->windingMomentum = + ADD_INT32( glyphpath->callbacks->windingMomentum, + cf2_getWindingMomentum( x1, y1, x2, y2 ) ); + + /* construct offset points */ + P0.x = ADD_INT32( glyphpath->currentCS.x, xOffset1 ); + P0.y = ADD_INT32( glyphpath->currentCS.y, yOffset1 ); + P1.x = ADD_INT32( x1, xOffset1 ); + P1.y = ADD_INT32( y1, yOffset1 ); + /* note: preserve angle of final segment by using offset3 at both ends */ + P2.x = ADD_INT32( x2, xOffset3 ); + P2.y = ADD_INT32( y2, yOffset3 ); + P3.x = ADD_INT32( x3, xOffset3 ); + P3.y = ADD_INT32( y3, yOffset3 ); + + if ( glyphpath->moveIsPending ) + { + /* emit offset 1st point as MoveTo */ + cf2_glyphpath_pushMove( glyphpath, P0 ); + + glyphpath->moveIsPending = FALSE; + glyphpath->pathIsOpen = TRUE; + + glyphpath->offsetStart1 = P1; /* record second point */ + } + + if ( glyphpath->elemIsQueued ) + { + FT_ASSERT( cf2_hintmap_isValid( &glyphpath->hintMap ) || + glyphpath->hintMap.count == 0 ); + + cf2_glyphpath_pushPrevElem( glyphpath, + &glyphpath->hintMap, + &P0, + P1, + FALSE ); + } + + /* queue the current element with offset points */ + glyphpath->elemIsQueued = TRUE; + glyphpath->prevElemOp = CF2_PathOpCubeTo; + glyphpath->prevElemP0 = P0; + glyphpath->prevElemP1 = P1; + glyphpath->prevElemP2 = P2; + glyphpath->prevElemP3 = P3; + + /* update current map */ + if ( cf2_hintmask_isNew( glyphpath->hintMask ) ) + cf2_hintmap_build( &glyphpath->hintMap, + glyphpath->hStemHintArray, + glyphpath->vStemHintArray, + glyphpath->hintMask, + glyphpath->hintOriginY, + FALSE ); + + glyphpath->currentCS.x = x3; /* pre-offset current point */ + glyphpath->currentCS.y = y3; + } + + + FT_LOCAL_DEF( void ) + cf2_glyphpath_closeOpenPath( CF2_GlyphPath glyphpath ) + { + if ( glyphpath->pathIsOpen ) + { + /* + * A closing line in Character Space line is always generated below + * with `cf2_glyphPath_lineTo'. It may be ignored later if it turns + * out to be zero length in Device Space. + */ + glyphpath->pathIsClosing = TRUE; + + cf2_glyphpath_lineTo( glyphpath, + glyphpath->start.x, + glyphpath->start.y ); + + /* empty the final element from the queue and close the path */ + if ( glyphpath->elemIsQueued ) + cf2_glyphpath_pushPrevElem( glyphpath, + &glyphpath->hintMap, + &glyphpath->offsetStart0, + glyphpath->offsetStart1, + TRUE ); + + /* reset state machine */ + glyphpath->moveIsPending = TRUE; + glyphpath->pathIsOpen = FALSE; + glyphpath->pathIsClosing = FALSE; + glyphpath->elemIsQueued = FALSE; + } + } + + +/* END */ |