diff options
Diffstat (limited to 'modules/freetype2/src/base/ftoutln.c')
-rw-r--r-- | modules/freetype2/src/base/ftoutln.c | 1118 |
1 files changed, 1118 insertions, 0 deletions
diff --git a/modules/freetype2/src/base/ftoutln.c b/modules/freetype2/src/base/ftoutln.c new file mode 100644 index 0000000000..134f39d2b1 --- /dev/null +++ b/modules/freetype2/src/base/ftoutln.c @@ -0,0 +1,1118 @@ +/**************************************************************************** + * + * ftoutln.c + * + * FreeType outline management (body). + * + * Copyright (C) 1996-2023 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. + * + */ + + +#include <freetype/ftoutln.h> +#include <freetype/internal/ftobjs.h> +#include <freetype/internal/ftcalc.h> +#include <freetype/internal/ftdebug.h> +#include <freetype/fttrigon.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 outline + + + static + const FT_Outline null_outline = { 0, 0, NULL, NULL, NULL, 0 }; + + + /* documentation is in ftoutln.h */ + + FT_EXPORT_DEF( FT_Error ) + FT_Outline_Decompose( FT_Outline* outline, + const FT_Outline_Funcs* func_interface, + void* user ) + { +#undef SCALED +#define SCALED( x ) ( (x) * ( 1L << shift ) - delta ) + + FT_Vector v_last; + FT_Vector v_control; + FT_Vector v_start; + + FT_Vector* point; + FT_Vector* limit; + char* tags; + + FT_Error error; + + FT_Int n; /* index of contour in outline */ + FT_Int first; /* index of first point in contour */ + FT_Int last; /* index of last point in contour */ + + FT_Int tag; /* current point's state */ + + FT_Int shift; + FT_Pos delta; + + + if ( !outline ) + return FT_THROW( Invalid_Outline ); + + if ( !func_interface ) + return FT_THROW( Invalid_Argument ); + + shift = func_interface->shift; + delta = func_interface->delta; + + last = -1; + for ( n = 0; n < outline->n_contours; n++ ) + { + FT_TRACE5(( "FT_Outline_Decompose: Contour %d\n", n )); + + first = last + 1; + last = outline->contours[n]; + if ( last < first ) + goto Invalid_Outline; + + limit = outline->points + last; + + v_start = outline->points[first]; + v_start.x = SCALED( v_start.x ); + v_start.y = SCALED( v_start.y ); + + v_last = outline->points[last]; + v_last.x = SCALED( v_last.x ); + v_last.y = SCALED( v_last.y ); + + v_control = v_start; + + point = outline->points + first; + tags = outline->tags + first; + tag = FT_CURVE_TAG( tags[0] ); + + /* A contour cannot start with a cubic control point! */ + if ( tag == FT_CURVE_TAG_CUBIC ) + goto Invalid_Outline; + + /* check first point to determine origin */ + if ( tag == FT_CURVE_TAG_CONIC ) + { + /* first point is conic control. Yes, this happens. */ + if ( FT_CURVE_TAG( outline->tags[last] ) == FT_CURVE_TAG_ON ) + { + /* start at last point if it is on the curve */ + v_start = v_last; + limit--; + } + else + { + /* if both first and last points are conic, */ + /* start at their middle and record its position */ + /* for closure */ + v_start.x = ( v_start.x + v_last.x ) / 2; + v_start.y = ( v_start.y + v_last.y ) / 2; + + /* v_last = v_start; */ + } + point--; + tags--; + } + + FT_TRACE5(( " move to (%.2f, %.2f)\n", + (double)v_start.x / 64, (double)v_start.y / 64 )); + error = func_interface->move_to( &v_start, user ); + if ( error ) + goto Exit; + + while ( point < limit ) + { + point++; + tags++; + + tag = FT_CURVE_TAG( tags[0] ); + switch ( tag ) + { + case FT_CURVE_TAG_ON: /* emit a single line_to */ + { + FT_Vector vec; + + + vec.x = SCALED( point->x ); + vec.y = SCALED( point->y ); + + FT_TRACE5(( " line to (%.2f, %.2f)\n", + (double)vec.x / 64, (double)vec.y / 64 )); + error = func_interface->line_to( &vec, user ); + if ( error ) + goto Exit; + continue; + } + + case FT_CURVE_TAG_CONIC: /* consume conic arcs */ + v_control.x = SCALED( point->x ); + v_control.y = SCALED( point->y ); + + Do_Conic: + if ( point < limit ) + { + FT_Vector vec; + FT_Vector v_middle; + + + point++; + tags++; + tag = FT_CURVE_TAG( tags[0] ); + + vec.x = SCALED( point->x ); + vec.y = SCALED( point->y ); + + if ( tag == FT_CURVE_TAG_ON ) + { + FT_TRACE5(( " conic to (%.2f, %.2f)" + " with control (%.2f, %.2f)\n", + (double)vec.x / 64, + (double)vec.y / 64, + (double)v_control.x / 64, + (double)v_control.y / 64 )); + error = func_interface->conic_to( &v_control, &vec, user ); + if ( error ) + goto Exit; + continue; + } + + if ( tag != FT_CURVE_TAG_CONIC ) + goto Invalid_Outline; + + v_middle.x = ( v_control.x + vec.x ) / 2; + v_middle.y = ( v_control.y + vec.y ) / 2; + + FT_TRACE5(( " conic to (%.2f, %.2f)" + " with control (%.2f, %.2f)\n", + (double)v_middle.x / 64, + (double)v_middle.y / 64, + (double)v_control.x / 64, + (double)v_control.y / 64 )); + error = func_interface->conic_to( &v_control, &v_middle, user ); + if ( error ) + goto Exit; + + v_control = vec; + goto Do_Conic; + } + + FT_TRACE5(( " conic to (%.2f, %.2f)" + " with control (%.2f, %.2f)\n", + (double)v_start.x / 64, + (double)v_start.y / 64, + (double)v_control.x / 64, + (double)v_control.y / 64 )); + error = func_interface->conic_to( &v_control, &v_start, user ); + goto Close; + + default: /* FT_CURVE_TAG_CUBIC */ + { + FT_Vector vec1, vec2; + + + if ( point + 1 > limit || + FT_CURVE_TAG( tags[1] ) != FT_CURVE_TAG_CUBIC ) + goto Invalid_Outline; + + point += 2; + tags += 2; + + vec1.x = SCALED( point[-2].x ); + vec1.y = SCALED( point[-2].y ); + + vec2.x = SCALED( point[-1].x ); + vec2.y = SCALED( point[-1].y ); + + if ( point <= limit ) + { + FT_Vector vec; + + + vec.x = SCALED( point->x ); + vec.y = SCALED( point->y ); + + FT_TRACE5(( " cubic to (%.2f, %.2f)" + " with controls (%.2f, %.2f) and (%.2f, %.2f)\n", + (double)vec.x / 64, + (double)vec.y / 64, + (double)vec1.x / 64, + (double)vec1.y / 64, + (double)vec2.x / 64, + (double)vec2.y / 64 )); + error = func_interface->cubic_to( &vec1, &vec2, &vec, user ); + if ( error ) + goto Exit; + continue; + } + + FT_TRACE5(( " cubic to (%.2f, %.2f)" + " with controls (%.2f, %.2f) and (%.2f, %.2f)\n", + (double)v_start.x / 64, + (double)v_start.y / 64, + (double)vec1.x / 64, + (double)vec1.y / 64, + (double)vec2.x / 64, + (double)vec2.y / 64 )); + error = func_interface->cubic_to( &vec1, &vec2, &v_start, user ); + goto Close; + } + } + } + + /* close the contour with a line segment */ + FT_TRACE5(( " line to (%.2f, %.2f)\n", + (double)v_start.x / 64, (double)v_start.y / 64 )); + error = func_interface->line_to( &v_start, user ); + + Close: + if ( error ) + goto Exit; + } + + FT_TRACE5(( "FT_Outline_Decompose: Done\n" )); + return FT_Err_Ok; + + Invalid_Outline: + error = FT_THROW( Invalid_Outline ); + /* fall through */ + + Exit: + FT_TRACE5(( "FT_Outline_Decompose: Error 0x%x\n", error )); + return error; + } + + + /* documentation is in ftoutln.h */ + + FT_EXPORT_DEF( FT_Error ) + FT_Outline_New( FT_Library library, + FT_UInt numPoints, + FT_Int numContours, + FT_Outline *anoutline ) + { + FT_Error error; + FT_Memory memory; + + + if ( !library ) + return FT_THROW( Invalid_Library_Handle ); + + memory = library->memory; + + if ( !anoutline || !memory ) + return FT_THROW( Invalid_Argument ); + + *anoutline = null_outline; + + if ( numContours < 0 || + (FT_UInt)numContours > numPoints ) + return FT_THROW( Invalid_Argument ); + + if ( numPoints > FT_OUTLINE_POINTS_MAX ) + return FT_THROW( Array_Too_Large ); + + if ( FT_NEW_ARRAY( anoutline->points, numPoints ) || + FT_NEW_ARRAY( anoutline->tags, numPoints ) || + FT_NEW_ARRAY( anoutline->contours, numContours ) ) + goto Fail; + + anoutline->n_points = (FT_Short)numPoints; + anoutline->n_contours = (FT_Short)numContours; + anoutline->flags |= FT_OUTLINE_OWNER; + + return FT_Err_Ok; + + Fail: + anoutline->flags |= FT_OUTLINE_OWNER; + FT_Outline_Done( library, anoutline ); + + return error; + } + + + /* documentation is in ftoutln.h */ + + FT_EXPORT_DEF( FT_Error ) + FT_Outline_Check( FT_Outline* outline ) + { + if ( outline ) + { + FT_Int n_points = outline->n_points; + FT_Int n_contours = outline->n_contours; + FT_Int end0, end; + FT_Int n; + + + /* empty glyph? */ + if ( n_points == 0 && n_contours == 0 ) + return FT_Err_Ok; + + /* check point and contour counts */ + if ( n_points <= 0 || n_contours <= 0 ) + goto Bad; + + end0 = -1; + for ( n = 0; n < n_contours; n++ ) + { + end = outline->contours[n]; + + /* note that we don't accept empty contours */ + if ( end <= end0 || end >= n_points ) + goto Bad; + + end0 = end; + } + + if ( end0 != n_points - 1 ) + goto Bad; + + /* XXX: check the tags array */ + return FT_Err_Ok; + } + + Bad: + return FT_THROW( Invalid_Outline ); + } + + + /* documentation is in ftoutln.h */ + + FT_EXPORT_DEF( FT_Error ) + FT_Outline_Copy( const FT_Outline* source, + FT_Outline *target ) + { + FT_Int is_owner; + + + if ( !source || !target ) + return FT_THROW( Invalid_Outline ); + + if ( source->n_points != target->n_points || + source->n_contours != target->n_contours ) + return FT_THROW( Invalid_Argument ); + + if ( source == target ) + return FT_Err_Ok; + + if ( source->n_points ) + { + FT_ARRAY_COPY( target->points, source->points, source->n_points ); + FT_ARRAY_COPY( target->tags, source->tags, source->n_points ); + } + + if ( source->n_contours ) + FT_ARRAY_COPY( target->contours, source->contours, source->n_contours ); + + /* copy all flags, except the `FT_OUTLINE_OWNER' one */ + is_owner = target->flags & FT_OUTLINE_OWNER; + target->flags = source->flags; + + target->flags &= ~FT_OUTLINE_OWNER; + target->flags |= is_owner; + + return FT_Err_Ok; + } + + + /* documentation is in ftoutln.h */ + + FT_EXPORT_DEF( FT_Error ) + FT_Outline_Done( FT_Library library, + FT_Outline* outline ) + { + FT_Memory memory; + + + if ( !library ) + return FT_THROW( Invalid_Library_Handle ); + + if ( !outline ) + return FT_THROW( Invalid_Outline ); + + memory = library->memory; + + if ( !memory ) + return FT_THROW( Invalid_Argument ); + + if ( outline->flags & FT_OUTLINE_OWNER ) + { + FT_FREE( outline->points ); + FT_FREE( outline->tags ); + FT_FREE( outline->contours ); + } + *outline = null_outline; + + return FT_Err_Ok; + } + + + /* documentation is in ftoutln.h */ + + FT_EXPORT_DEF( void ) + FT_Outline_Get_CBox( const FT_Outline* outline, + FT_BBox *acbox ) + { + FT_Pos xMin, yMin, xMax, yMax; + + + if ( outline && acbox ) + { + if ( outline->n_points == 0 ) + { + xMin = 0; + yMin = 0; + xMax = 0; + yMax = 0; + } + else + { + FT_Vector* vec = outline->points; + FT_Vector* limit = vec + outline->n_points; + + + xMin = xMax = vec->x; + yMin = yMax = vec->y; + vec++; + + for ( ; vec < limit; vec++ ) + { + FT_Pos x, y; + + + x = vec->x; + if ( x < xMin ) xMin = x; + if ( x > xMax ) xMax = x; + + y = vec->y; + if ( y < yMin ) yMin = y; + if ( y > yMax ) yMax = y; + } + } + acbox->xMin = xMin; + acbox->xMax = xMax; + acbox->yMin = yMin; + acbox->yMax = yMax; + } + } + + + /* documentation is in ftoutln.h */ + + FT_EXPORT_DEF( void ) + FT_Outline_Translate( const FT_Outline* outline, + FT_Pos xOffset, + FT_Pos yOffset ) + { + FT_UShort n; + FT_Vector* vec; + + + if ( !outline ) + return; + + vec = outline->points; + + for ( n = 0; n < outline->n_points; n++ ) + { + vec->x = ADD_LONG( vec->x, xOffset ); + vec->y = ADD_LONG( vec->y, yOffset ); + vec++; + } + } + + + /* documentation is in ftoutln.h */ + + FT_EXPORT_DEF( void ) + FT_Outline_Reverse( FT_Outline* outline ) + { + FT_UShort n; + FT_Int first, last; + + + if ( !outline ) + return; + + last = -1; + for ( n = 0; n < outline->n_contours; n++ ) + { + /* keep the first contour point as is and swap points around it */ + /* to guarantee that the cubic arches stay valid after reverse */ + first = last + 2; + last = outline->contours[n]; + + /* reverse point table */ + { + FT_Vector* p = outline->points + first; + FT_Vector* q = outline->points + last; + FT_Vector swap; + + + while ( p < q ) + { + swap = *p; + *p = *q; + *q = swap; + p++; + q--; + } + } + + /* reverse tags table */ + { + char* p = outline->tags + first; + char* q = outline->tags + last; + + + while ( p < q ) + { + char swap; + + + swap = *p; + *p = *q; + *q = swap; + p++; + q--; + } + } + } + + outline->flags ^= FT_OUTLINE_REVERSE_FILL; + } + + + /* documentation is in ftoutln.h */ + + FT_EXPORT_DEF( FT_Error ) + FT_Outline_Render( FT_Library library, + FT_Outline* outline, + FT_Raster_Params* params ) + { + FT_Error error; + FT_Renderer renderer; + FT_ListNode node; + FT_BBox cbox; + + + if ( !library ) + return FT_THROW( Invalid_Library_Handle ); + + if ( !outline ) + return FT_THROW( Invalid_Outline ); + + if ( !params ) + return FT_THROW( Invalid_Argument ); + + FT_Outline_Get_CBox( outline, &cbox ); + if ( cbox.xMin < -0x1000000L || cbox.yMin < -0x1000000L || + cbox.xMax > 0x1000000L || cbox.yMax > 0x1000000L ) + return FT_THROW( Invalid_Outline ); + + renderer = library->cur_renderer; + node = library->renderers.head; + + params->source = (void*)outline; + + /* preset clip_box for direct mode */ + if ( params->flags & FT_RASTER_FLAG_DIRECT && + !( params->flags & FT_RASTER_FLAG_CLIP ) ) + { + params->clip_box.xMin = cbox.xMin >> 6; + params->clip_box.yMin = cbox.yMin >> 6; + params->clip_box.xMax = ( cbox.xMax + 63 ) >> 6; + params->clip_box.yMax = ( cbox.yMax + 63 ) >> 6; + } + + error = FT_ERR( Cannot_Render_Glyph ); + while ( renderer ) + { + error = renderer->raster_render( renderer->raster, params ); + if ( !error || FT_ERR_NEQ( error, Cannot_Render_Glyph ) ) + break; + + /* FT_Err_Cannot_Render_Glyph is returned if the render mode */ + /* is unsupported by the current renderer for this glyph image */ + /* format */ + + /* now, look for another renderer that supports the same */ + /* format */ + renderer = FT_Lookup_Renderer( library, FT_GLYPH_FORMAT_OUTLINE, + &node ); + } + + return error; + } + + + /* documentation is in ftoutln.h */ + + FT_EXPORT_DEF( FT_Error ) + FT_Outline_Get_Bitmap( FT_Library library, + FT_Outline* outline, + const FT_Bitmap *abitmap ) + { + FT_Raster_Params params; + + + if ( !abitmap ) + return FT_THROW( Invalid_Argument ); + + /* other checks are delayed to `FT_Outline_Render' */ + + params.target = abitmap; + params.flags = 0; + + if ( abitmap->pixel_mode == FT_PIXEL_MODE_GRAY || + abitmap->pixel_mode == FT_PIXEL_MODE_LCD || + abitmap->pixel_mode == FT_PIXEL_MODE_LCD_V ) + params.flags |= FT_RASTER_FLAG_AA; + + return FT_Outline_Render( library, outline, ¶ms ); + } + + + /* documentation is in freetype.h */ + + FT_EXPORT_DEF( void ) + FT_Vector_Transform( FT_Vector* vector, + const FT_Matrix* matrix ) + { + FT_Pos xz, yz; + + + if ( !vector || !matrix ) + return; + + xz = FT_MulFix( vector->x, matrix->xx ) + + FT_MulFix( vector->y, matrix->xy ); + + yz = FT_MulFix( vector->x, matrix->yx ) + + FT_MulFix( vector->y, matrix->yy ); + + vector->x = xz; + vector->y = yz; + } + + + /* documentation is in ftoutln.h */ + + FT_EXPORT_DEF( void ) + FT_Outline_Transform( const FT_Outline* outline, + const FT_Matrix* matrix ) + { + FT_Vector* vec; + FT_Vector* limit; + + + if ( !outline || !matrix || !outline->points ) + return; + + vec = outline->points; + limit = vec + outline->n_points; + + for ( ; vec < limit; vec++ ) + FT_Vector_Transform( vec, matrix ); + } + + +#if 0 + +#define FT_OUTLINE_GET_CONTOUR( outline, c, first, last ) \ + do \ + { \ + (first) = ( c > 0 ) ? (outline)->points + \ + (outline)->contours[c - 1] + 1 \ + : (outline)->points; \ + (last) = (outline)->points + (outline)->contours[c]; \ + } while ( 0 ) + + + /* Is a point in some contour? */ + /* */ + /* We treat every point of the contour as if it */ + /* it were ON. That is, we allow false positives, */ + /* but disallow false negatives. (XXX really?) */ + static FT_Bool + ft_contour_has( FT_Outline* outline, + FT_Short c, + FT_Vector* point ) + { + FT_Vector* first; + FT_Vector* last; + FT_Vector* a; + FT_Vector* b; + FT_UInt n = 0; + + + FT_OUTLINE_GET_CONTOUR( outline, c, first, last ); + + for ( a = first; a <= last; a++ ) + { + FT_Pos x; + FT_Int intersect; + + + b = ( a == last ) ? first : a + 1; + + intersect = ( a->y - point->y ) ^ ( b->y - point->y ); + + /* a and b are on the same side */ + if ( intersect >= 0 ) + { + if ( intersect == 0 && a->y == point->y ) + { + if ( ( a->x <= point->x && b->x >= point->x ) || + ( a->x >= point->x && b->x <= point->x ) ) + return 1; + } + + continue; + } + + x = a->x + ( b->x - a->x ) * (point->y - a->y ) / ( b->y - a->y ); + + if ( x < point->x ) + n++; + else if ( x == point->x ) + return 1; + } + + return n & 1; + } + + + static FT_Bool + ft_contour_enclosed( FT_Outline* outline, + FT_UShort c ) + { + FT_Vector* first; + FT_Vector* last; + FT_Short i; + + + FT_OUTLINE_GET_CONTOUR( outline, c, first, last ); + + for ( i = 0; i < outline->n_contours; i++ ) + { + if ( i != c && ft_contour_has( outline, i, first ) ) + { + FT_Vector* pt; + + + for ( pt = first + 1; pt <= last; pt++ ) + if ( !ft_contour_has( outline, i, pt ) ) + return 0; + + return 1; + } + } + + return 0; + } + + + /* This version differs from the public one in that each */ + /* part (contour not enclosed in another contour) of the */ + /* outline is checked for orientation. This is */ + /* necessary for some buggy CJK fonts. */ + static FT_Orientation + ft_outline_get_orientation( FT_Outline* outline ) + { + FT_Short i; + FT_Vector* first; + FT_Vector* last; + FT_Orientation orient = FT_ORIENTATION_NONE; + + + first = outline->points; + for ( i = 0; i < outline->n_contours; i++, first = last + 1 ) + { + FT_Vector* point; + FT_Vector* xmin_point; + FT_Pos xmin; + + + last = outline->points + outline->contours[i]; + + /* skip degenerate contours */ + if ( last < first + 2 ) + continue; + + if ( ft_contour_enclosed( outline, i ) ) + continue; + + xmin = first->x; + xmin_point = first; + + for ( point = first + 1; point <= last; point++ ) + { + if ( point->x < xmin ) + { + xmin = point->x; + xmin_point = point; + } + } + + /* check the orientation of the contour */ + { + FT_Vector* prev; + FT_Vector* next; + FT_Orientation o; + + + prev = ( xmin_point == first ) ? last : xmin_point - 1; + next = ( xmin_point == last ) ? first : xmin_point + 1; + + if ( FT_Atan2( prev->x - xmin_point->x, prev->y - xmin_point->y ) > + FT_Atan2( next->x - xmin_point->x, next->y - xmin_point->y ) ) + o = FT_ORIENTATION_POSTSCRIPT; + else + o = FT_ORIENTATION_TRUETYPE; + + if ( orient == FT_ORIENTATION_NONE ) + orient = o; + else if ( orient != o ) + return FT_ORIENTATION_NONE; + } + } + + return orient; + } + +#endif /* 0 */ + + + /* documentation is in ftoutln.h */ + + FT_EXPORT_DEF( FT_Error ) + FT_Outline_Embolden( FT_Outline* outline, + FT_Pos strength ) + { + return FT_Outline_EmboldenXY( outline, strength, strength ); + } + + + /* documentation is in ftoutln.h */ + + FT_EXPORT_DEF( FT_Error ) + FT_Outline_EmboldenXY( FT_Outline* outline, + FT_Pos xstrength, + FT_Pos ystrength ) + { + FT_Vector* points; + FT_Int c, first, last; + FT_Orientation orientation; + + + if ( !outline ) + return FT_THROW( Invalid_Outline ); + + xstrength /= 2; + ystrength /= 2; + if ( xstrength == 0 && ystrength == 0 ) + return FT_Err_Ok; + + orientation = FT_Outline_Get_Orientation( outline ); + if ( orientation == FT_ORIENTATION_NONE ) + { + if ( outline->n_contours ) + return FT_THROW( Invalid_Argument ); + else + return FT_Err_Ok; + } + + points = outline->points; + + last = -1; + for ( c = 0; c < outline->n_contours; c++ ) + { + FT_Vector in, out, anchor, shift; + FT_Fixed l_in, l_out, l_anchor = 0, l, q, d; + FT_Int i, j, k; + + + first = last + 1; + last = outline->contours[c]; + l_in = 0; + + /* pacify compiler */ + in.x = in.y = anchor.x = anchor.y = 0; + + /* Counter j cycles though the points; counter i advances only */ + /* when points are moved; anchor k marks the first moved point. */ + for ( i = last, j = first, k = -1; + j != i && i != k; + j = j < last ? j + 1 : first ) + { + if ( j != k ) + { + out.x = points[j].x - points[i].x; + out.y = points[j].y - points[i].y; + l_out = (FT_Fixed)FT_Vector_NormLen( &out ); + + if ( l_out == 0 ) + continue; + } + else + { + out = anchor; + l_out = l_anchor; + } + + if ( l_in != 0 ) + { + if ( k < 0 ) + { + k = i; + anchor = in; + l_anchor = l_in; + } + + d = FT_MulFix( in.x, out.x ) + FT_MulFix( in.y, out.y ); + + /* shift only if turn is less than ~160 degrees */ + if ( d > -0xF000L ) + { + d = d + 0x10000L; + + /* shift components along lateral bisector in proper orientation */ + shift.x = in.y + out.y; + shift.y = in.x + out.x; + + if ( orientation == FT_ORIENTATION_TRUETYPE ) + shift.x = -shift.x; + else + shift.y = -shift.y; + + /* restrict shift magnitude to better handle collapsing segments */ + q = FT_MulFix( out.x, in.y ) - FT_MulFix( out.y, in.x ); + if ( orientation == FT_ORIENTATION_TRUETYPE ) + q = -q; + + l = FT_MIN( l_in, l_out ); + + /* non-strict inequalities avoid divide-by-zero when q == l == 0 */ + if ( FT_MulFix( xstrength, q ) <= FT_MulFix( l, d ) ) + shift.x = FT_MulDiv( shift.x, xstrength, d ); + else + shift.x = FT_MulDiv( shift.x, l, q ); + + + if ( FT_MulFix( ystrength, q ) <= FT_MulFix( l, d ) ) + shift.y = FT_MulDiv( shift.y, ystrength, d ); + else + shift.y = FT_MulDiv( shift.y, l, q ); + } + else + shift.x = shift.y = 0; + + for ( ; + i != j; + i = i < last ? i + 1 : first ) + { + points[i].x += xstrength + shift.x; + points[i].y += ystrength + shift.y; + } + } + else + i = j; + + in = out; + l_in = l_out; + } + } + + return FT_Err_Ok; + } + + + /* documentation is in ftoutln.h */ + + FT_EXPORT_DEF( FT_Orientation ) + FT_Outline_Get_Orientation( FT_Outline* outline ) + { + FT_BBox cbox = { 0, 0, 0, 0 }; + FT_Int xshift, yshift; + FT_Vector* points; + FT_Vector v_prev, v_cur; + FT_Int c, n, first, last; + FT_Pos area = 0; + + + if ( !outline || outline->n_points <= 0 ) + return FT_ORIENTATION_TRUETYPE; + + /* We use the nonzero winding rule to find the orientation. */ + /* Since glyph outlines behave much more `regular' than arbitrary */ + /* cubic or quadratic curves, this test deals with the polygon */ + /* only that is spanned up by the control points. */ + + FT_Outline_Get_CBox( outline, &cbox ); + + /* Handle collapsed outlines to avoid undefined FT_MSB. */ + if ( cbox.xMin == cbox.xMax || cbox.yMin == cbox.yMax ) + return FT_ORIENTATION_NONE; + + /* Reject values large outlines. */ + if ( cbox.xMin < -0x1000000L || cbox.yMin < -0x1000000L || + cbox.xMax > 0x1000000L || cbox.yMax > 0x1000000L ) + return FT_ORIENTATION_NONE; + + xshift = FT_MSB( (FT_UInt32)( FT_ABS( cbox.xMax ) | + FT_ABS( cbox.xMin ) ) ) - 14; + xshift = FT_MAX( xshift, 0 ); + + yshift = FT_MSB( (FT_UInt32)( cbox.yMax - cbox.yMin ) ) - 14; + yshift = FT_MAX( yshift, 0 ); + + points = outline->points; + + last = -1; + for ( c = 0; c < outline->n_contours; c++ ) + { + first = last + 1; + last = outline->contours[c]; + + v_prev.x = points[last].x >> xshift; + v_prev.y = points[last].y >> yshift; + + for ( n = first; n <= last; n++ ) + { + v_cur.x = points[n].x >> xshift; + v_cur.y = points[n].y >> yshift; + + area = ADD_LONG( area, + MUL_LONG( v_cur.y - v_prev.y, + v_cur.x + v_prev.x ) ); + + v_prev = v_cur; + } + } + + if ( area > 0 ) + return FT_ORIENTATION_POSTSCRIPT; + else if ( area < 0 ) + return FT_ORIENTATION_TRUETYPE; + else + return FT_ORIENTATION_NONE; + } + + +/* END */ |