+++ /dev/null
-/***************************************************************************/
-/* */
-/* ahglobal.c */
-/* */
-/* Routines used to compute global metrics automatically (body). */
-/* */
-/* Copyright 2000-2001 Catharon Productions Inc. */
-/* Author: David Turner */
-/* */
-/* This file is part of the Catharon Typography Project and shall only */
-/* be used, modified, and distributed under the terms of the Catharon */
-/* Open Source License that should come with this file under the name */
-/* `CatharonLicense.txt'. By continuing to use, modify, or distribute */
-/* this file you indicate that you have read the license and */
-/* understand and accept it fully. */
-/* */
-/* Note that this license is compatible with the FreeType license. */
-/* */
-/***************************************************************************/
-
-
-#include <ft2build.h>
-#include FT_INTERNAL_DEBUG_H
-#include "ahglobal.h"
-#include "ahglyph.h"
-
-
-#define MAX_TEST_CHARACTERS 12
-
- static
- const char* blue_chars[ah_blue_max] =
- {
- "THEZOCQS",
- "HEZLOCUS",
- "xzroesc",
- "xzroesc",
- "pqgjy"
- };
-
-
- /* simple insertion sort */
- static void
- sort_values( FT_Int count,
- FT_Pos* table )
- {
- FT_Int i, j, swap;
-
-
- for ( i = 1; i < count; i++ )
- {
- for ( j = i; j > 0; j-- )
- {
- if ( table[j] > table[j - 1] )
- break;
-
- swap = table[j];
- table[j] = table[j - 1];
- table[j - 1] = swap;
- }
- }
- }
-
-
- static FT_Error
- ah_hinter_compute_blues( AH_Hinter* hinter )
- {
- AH_Blue blue;
- AH_Globals* globals = &hinter->globals->design;
- FT_Pos flats [MAX_TEST_CHARACTERS];
- FT_Pos rounds[MAX_TEST_CHARACTERS];
- FT_Int num_flats;
- FT_Int num_rounds;
-
- FT_Face face;
- FT_GlyphSlot glyph;
- FT_Error error;
- FT_CharMap charmap;
-
-
- face = hinter->face;
- glyph = face->glyph;
-
- /* save current charmap */
- charmap = face->charmap;
-
- /* do we have a Unicode charmap in there? */
- error = FT_Select_Charmap( face, ft_encoding_unicode );
- if ( error )
- goto Exit;
-
- /* we compute the blues simply by loading each character from the */
- /* 'blue_chars[blues]' string, then compute its top-most and */
- /* bottom-most points */
-
- AH_LOG(( "blue zones computation\n" ));
- AH_LOG(( "------------------------------------------------\n" ));
-
- for ( blue = ah_blue_capital_top; blue < ah_blue_max; blue++ )
- {
- const char* p = blue_chars[blue];
- const char* limit = p + MAX_TEST_CHARACTERS;
- FT_Pos *blue_ref, *blue_shoot;
-
-
- AH_LOG(( "blue %3d: ", blue ));
-
- num_flats = 0;
- num_rounds = 0;
-
- for ( ; p < limit; p++ )
- {
- FT_UInt glyph_index;
- FT_Vector* extremum;
- FT_Vector* points;
- FT_Vector* point_limit;
- FT_Vector* point;
- FT_Bool round;
-
-
- /* exit if we reach the end of the string */
- if ( !*p )
- break;
-
- AH_LOG(( "`%c'", *p ));
-
- /* load the character in the face -- skip unknown or empty ones */
- glyph_index = FT_Get_Char_Index( face, (FT_UInt)*p );
- if ( glyph_index == 0 )
- continue;
-
- error = FT_Load_Glyph( face, glyph_index, FT_LOAD_NO_SCALE );
- if ( error || glyph->outline.n_points <= 0 )
- continue;
-
- /* now compute min or max point indices and coordinates */
- points = glyph->outline.points;
- point_limit = points + glyph->outline.n_points;
- point = points;
- extremum = point;
- point++;
-
- if ( AH_IS_TOP_BLUE( blue ) )
- {
- for ( ; point < point_limit; point++ )
- if ( point->y > extremum->y )
- extremum = point;
- }
- else
- {
- for ( ; point < point_limit; point++ )
- if ( point->y < extremum->y )
- extremum = point;
- }
-
- AH_LOG(( "%5d", (int)extremum->y ));
-
- /* now, check whether the point belongs to a straight or round */
- /* segment; we first need to find in which contour the extremum */
- /* lies, then see its previous and next points */
- {
- FT_Int index = (FT_Int)( extremum - points );
- FT_Int n;
- FT_Int first, last, prev, next, end;
- FT_Pos dist;
-
-
- last = -1;
- first = 0;
-
- for ( n = 0; n < glyph->outline.n_contours; n++ )
- {
- end = glyph->outline.contours[n];
- if ( end >= index )
- {
- last = end;
- break;
- }
- first = end + 1;
- }
-
- /* XXX: should never happen! */
- if ( last < 0 )
- continue;
-
- /* now look for the previous and next points that are not on the */
- /* same Y coordinate. Threshold the `closeness'... */
-
- prev = index;
- next = prev;
-
- do
- {
- if ( prev > first )
- prev--;
- else
- prev = last;
-
- dist = points[prev].y - extremum->y;
- if ( dist < -5 || dist > 5 )
- break;
-
- } while ( prev != index );
-
- do
- {
- if ( next < last )
- next++;
- else
- next = first;
-
- dist = points[next].y - extremum->y;
- if ( dist < -5 || dist > 5 )
- break;
-
- } while ( next != index );
-
- /* now, set the `round' flag depending on the segment's kind */
- round = FT_BOOL(
- FT_CURVE_TAG( glyph->outline.tags[prev] ) != FT_Curve_Tag_On ||
- FT_CURVE_TAG( glyph->outline.tags[next] ) != FT_Curve_Tag_On );
-
- AH_LOG(( "%c ", round ? 'r' : 'f' ));
- }
-
- if ( round )
- rounds[num_rounds++] = extremum->y;
- else
- flats[num_flats++] = extremum->y;
- }
-
- AH_LOG(( "\n" ));
-
- /* we have computed the contents of the `rounds' and `flats' tables, */
- /* now determine the reference and overshoot position of the blue; */
- /* we simply take the median value after a simple short */
- sort_values( num_rounds, rounds );
- sort_values( num_flats, flats );
-
- blue_ref = globals->blue_refs + blue;
- blue_shoot = globals->blue_shoots + blue;
- if ( num_flats == 0 && num_rounds == 0 )
- {
- *blue_ref = -10000;
- *blue_shoot = -10000;
- }
- else if ( num_flats == 0 )
- {
- *blue_ref =
- *blue_shoot = rounds[num_rounds / 2];
- }
- else if ( num_rounds == 0 )
- {
- *blue_ref =
- *blue_shoot = flats[num_flats / 2];
- }
- else
- {
- *blue_ref = flats[num_flats / 2];
- *blue_shoot = rounds[num_rounds / 2];
- }
-
- /* there are sometimes problems: if the overshoot position of top */
- /* zones is under its reference position, or the opposite for bottom */
- /* zones. We must thus check everything there and correct the errors */
- if ( *blue_shoot != *blue_ref )
- {
- FT_Pos ref = *blue_ref;
- FT_Pos shoot = *blue_shoot;
- FT_Bool over_ref = FT_BOOL( shoot > ref );
-
-
- if ( AH_IS_TOP_BLUE( blue ) ^ over_ref )
- *blue_shoot = *blue_ref = ( shoot + ref ) / 2;
- }
-
- AH_LOG(( "-- ref = %ld, shoot = %ld\n", *blue_ref, *blue_shoot ));
- }
-
- /* reset original face charmap */
- FT_Set_Charmap( face, charmap );
- error = 0;
-
- Exit:
- return error;
- }
-
-
- static FT_Error
- ah_hinter_compute_widths( AH_Hinter* hinter )
- {
- /* scan the array of segments in each direction */
- AH_Outline* outline = hinter->glyph;
- AH_Segment* segments;
- AH_Segment* limit;
- AH_Globals* globals = &hinter->globals->design;
- FT_Pos* widths;
- FT_Int dimension;
- FT_Int* p_num_widths;
- FT_Error error = 0;
- FT_Pos edge_distance_threshold = 32000;
-
-
- globals->num_widths = 0;
- globals->num_heights = 0;
-
- /* For now, compute the standard width and height from the `o' */
- /* character. I started computing the stem width of the `i' and the */
- /* stem height of the "-", but it wasn't too good. Moreover, we now */
- /* have a single character that gives us standard width and height. */
- {
- FT_UInt glyph_index;
-
-
- glyph_index = FT_Get_Char_Index( hinter->face, 'o' );
- if ( glyph_index == 0 )
- return 0;
-
- error = FT_Load_Glyph( hinter->face, glyph_index, FT_LOAD_NO_SCALE );
- if ( error )
- goto Exit;
-
- error = ah_outline_load( hinter->glyph, hinter->face );
- if ( error )
- goto Exit;
-
- ah_outline_compute_segments( hinter->glyph );
- ah_outline_link_segments( hinter->glyph );
- }
-
- segments = outline->horz_segments;
- limit = segments + outline->num_hsegments;
- widths = globals->heights;
- p_num_widths = &globals->num_heights;
-
- for ( dimension = 1; dimension >= 0; dimension-- )
- {
- AH_Segment* seg = segments;
- AH_Segment* link;
- FT_Int num_widths = 0;
-
-
- for ( ; seg < limit; seg++ )
- {
- link = seg->link;
- /* we only consider stem segments there! */
- if ( link && link->link == seg && link > seg )
- {
- FT_Int dist;
-
-
- dist = seg->pos - link->pos;
- if ( dist < 0 )
- dist = -dist;
-
- if ( num_widths < 12 )
- widths[num_widths++] = dist;
- }
- }
-
- sort_values( num_widths, widths );
- *p_num_widths = num_widths;
-
- /* we will now try to find the smallest width */
- if ( num_widths > 0 && widths[0] < edge_distance_threshold )
- edge_distance_threshold = widths[0];
-
- segments = outline->vert_segments;
- limit = segments + outline->num_vsegments;
- widths = globals->widths;
- p_num_widths = &globals->num_widths;
-
- }
-
- /* Now, compute the edge distance threshold as a fraction of the */
- /* smallest width in the font. Set it in `hinter.glyph' too! */
- if ( edge_distance_threshold == 32000 )
- edge_distance_threshold = 50;
-
- /* let's try 20% */
- hinter->glyph->edge_distance_threshold = edge_distance_threshold / 5;
-
- Exit:
- return error;
- }
-
-
- FT_LOCAL_DEF FT_Error
- ah_hinter_compute_globals( AH_Hinter* hinter )
- {
- return ah_hinter_compute_widths( hinter ) ||
- ah_hinter_compute_blues ( hinter );
- }
-
-
-/* END */
projects / rrdtool.git / blobdiff