/***************************************************************************/ | |
/* */ | |
/* ftoutln.c */ | |
/* */ | |
/* FreeType outline management (body). */ | |
/* */ | |
/* Copyright 1996-2015 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. */ | |
/* */ | |
/***************************************************************************/ | |
/*************************************************************************/ | |
/* */ | |
/* All functions are declared in freetype.h. */ | |
/* */ | |
/*************************************************************************/ | |
#include <ft2build.h> | |
#include FT_OUTLINE_H | |
#include FT_INTERNAL_OBJECTS_H | |
#include FT_INTERNAL_CALC_H | |
#include FT_INTERNAL_DEBUG_H | |
#include FT_TRIGONOMETRY_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_outline | |
static | |
const FT_Outline null_outline = { 0, 0, 0, 0, 0, 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) < 0 ? -( -(x) << shift ) \ | |
: ( (x) << 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_UInt first; /* index of first 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; | |
first = 0; | |
for ( n = 0; n < outline->n_contours; n++ ) | |
{ | |
FT_Int last; /* index of last point in contour */ | |
FT_TRACE5(( "FT_Outline_Decompose: Outline %d\n", n )); | |
last = outline->contours[n]; | |
if ( last < 0 ) | |
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", | |
v_start.x / 64.0, v_start.y / 64.0 )); | |
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", | |
vec.x / 64.0, vec.y / 64.0 )); | |
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", | |
vec.x / 64.0, vec.y / 64.0, | |
v_control.x / 64.0, v_control.y / 64.0 )); | |
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", | |
v_middle.x / 64.0, v_middle.y / 64.0, | |
v_control.x / 64.0, v_control.y / 64.0 )); | |
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", | |
v_start.x / 64.0, v_start.y / 64.0, | |
v_control.x / 64.0, v_control.y / 64.0 )); | |
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", | |
vec.x / 64.0, vec.y / 64.0, | |
vec1.x / 64.0, vec1.y / 64.0, | |
vec2.x / 64.0, vec2.y / 64.0 )); | |
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", | |
v_start.x / 64.0, v_start.y / 64.0, | |
vec1.x / 64.0, vec1.y / 64.0, | |
vec2.x / 64.0, vec2.y / 64.0 )); | |
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", | |
v_start.x / 64.0, v_start.y / 64.0 )); | |
error = func_interface->line_to( &v_start, user ); | |
Close: | |
if ( error ) | |
goto Exit; | |
first = (FT_UInt)last + 1; | |
} | |
FT_TRACE5(( "FT_Outline_Decompose: Done\n", n )); | |
return FT_Err_Ok; | |
Exit: | |
FT_TRACE5(( "FT_Outline_Decompose: Error %d\n", error )); | |
return error; | |
Invalid_Outline: | |
return FT_THROW( Invalid_Outline ); | |
} | |
FT_EXPORT_DEF( FT_Error ) | |
FT_Outline_New_Internal( FT_Memory memory, | |
FT_UInt numPoints, | |
FT_Int numContours, | |
FT_Outline *anoutline ) | |
{ | |
FT_Error error; | |
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_Internal( memory, anoutline ); | |
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 ) | |
{ | |
if ( !library ) | |
return FT_THROW( Invalid_Library_Handle ); | |
return FT_Outline_New_Internal( library->memory, numPoints, | |
numContours, anoutline ); | |
} | |
/* 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 = end = -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 ( end != n_points - 1 ) | |
goto Bad; | |
/* XXX: check the tags array */ | |
return FT_Err_Ok; | |
} | |
Bad: | |
return FT_THROW( Invalid_Argument ); | |
} | |
/* 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; | |
FT_ARRAY_COPY( target->points, source->points, source->n_points ); | |
FT_ARRAY_COPY( target->tags, source->tags, source->n_points ); | |
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; | |
} | |
FT_EXPORT_DEF( FT_Error ) | |
FT_Outline_Done_Internal( FT_Memory memory, | |
FT_Outline* outline ) | |
{ | |
if ( !outline ) | |
return FT_THROW( Invalid_Outline ); | |
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( FT_Error ) | |
FT_Outline_Done( FT_Library library, | |
FT_Outline* outline ) | |
{ | |
/* check for valid `outline' in FT_Outline_Done_Internal() */ | |
if ( !library ) | |
return FT_THROW( Invalid_Library_Handle ); | |
return FT_Outline_Done_Internal( library->memory, outline ); | |
} | |
/* 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 += xOffset; | |
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; | |
first = 0; | |
for ( n = 0; n < outline->n_contours; n++ ) | |
{ | |
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--; | |
} | |
} | |
first = last + 1; | |
} | |
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; | |
if ( !library ) | |
return FT_THROW( Invalid_Library_Handle ); | |
if ( !outline ) | |
return FT_THROW( Invalid_Outline ); | |
if ( !params ) | |
return FT_THROW( Invalid_Argument ); | |
renderer = library->cur_renderer; | |
node = library->renderers.head; | |
params->source = (void*)outline; | |
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 ) | |
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_Int 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; | |
first = 0; | |
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; | |
l_in = 0; | |
last = outline->contours[c]; | |
/* 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; | |
} | |
first = last + 1; | |
} | |
return FT_Err_Ok; | |
} | |
/* documentation is in ftoutln.h */ | |
FT_EXPORT_DEF( FT_Orientation ) | |
FT_Outline_Get_Orientation( FT_Outline* outline ) | |
{ | |
FT_BBox cbox; | |
FT_Int xshift, yshift; | |
FT_Vector* points; | |
FT_Vector v_prev, v_cur; | |
FT_Int c, n, first; | |
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; | |
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; | |
first = 0; | |
for ( c = 0; c < outline->n_contours; c++ ) | |
{ | |
FT_Int 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 += ( v_cur.y - v_prev.y ) * ( v_cur.x + v_prev.x ); | |
v_prev = v_cur; | |
} | |
first = last + 1; | |
} | |
if ( area > 0 ) | |
return FT_ORIENTATION_POSTSCRIPT; | |
else if ( area < 0 ) | |
return FT_ORIENTATION_TRUETYPE; | |
else | |
return FT_ORIENTATION_NONE; | |
} | |
/* END */ |