/TeXmacs-1.0.7.11-src/src/Graphics/Fonts/compound_font.cpp

/******************************************************************************
* MODULE     : compound_font.cpp
* DESCRIPTION: fonts which are agglomerated from several other fonts.
* COPYRIGHT  : (C) 2005  Joris van der Hoeven
*******************************************************************************
* This software falls under the GNU general public license version 3 or later.
* It comes WITHOUT ANY WARRANTY WHATSOEVER. For details, see the file LICENSE
* in the root directory or <http://www.gnu.org/licenses/gpl-3.0.html>.
******************************************************************************/

#include "font.hpp"
#include "charmap.hpp"
#include "convert.hpp"

/******************************************************************************
* The compound font class
******************************************************************************/

static tree
map_car (tree t) {
  int i, n= N(t);
  tree r (TUPLE, n);
  for (i=0; i<n; i++)
    r[i]= t[i][0];
  return r;
}

struct compound_font_rep: font_rep {
  scheme_tree  def;
  array<font>  fn;
  charmap      cm;

  compound_font_rep (string name, scheme_tree def, array<font> fn);
  void   advance (string s, int& pos, string& r, int& ch);
  void   get_extents (string s, metric& ex);
  void   draw (renderer ren, string s, SI x, SI y);
  glyph  get_glyph (string s);
  double get_left_slope  (string s);
  double get_right_slope (string s);
  SI     get_left_correction  (string s);
  SI     get_right_correction (string s);
};

compound_font_rep::compound_font_rep (
  string name, scheme_tree def2, array<font> fn2):
    font_rep (name, fn2[0]),
    def (def2), fn (fn2), cm (load_charmap (map_car (def)))
{}

void
compound_font_rep::advance (string s, int& pos, string& r, int& ch) {
  cm->advance (s, pos, r, ch);
  //cout << "(r,ch)= (" << r << "," << ch << ")\n";
  if (ch>0 && is_nil (fn[ch])) {
    tree t= def[ch][1];
    if (is_tuple (t, "virtual", 3))
      fn[ch]= virtual_font (this, as_string(t[1]), as_int(t[2]), as_int(t[3]));
    else fn[ch]= find_font (t);
    ASSERT (!is_nil (fn[ch]), "font not found");
    //fn[ch]->copy_math_pars (fn[0]);
  }
}

/******************************************************************************
* Getting extents and drawing strings
******************************************************************************/

static string empty_string ("");

void
compound_font_rep::get_extents (string s, metric& ex) {
  int i=0, n= N(s);
  fn[0]->get_extents (empty_string, ex);
  while (i < n) {
    int nr;
    string r= s;
    metric ey;
    advance (s, i, r, nr);
    if (nr >= 0) {
      fn[nr]->get_extents (r, ey);
      ex->y1= min (ex->y1, ey->y1);
      ex->y2= max (ex->y2, ey->y2);
      ex->x3= min (ex->x3, ex->x2 + ey->x3);
      ex->y3= min (ex->y3, ey->y3);
      ex->x4= max (ex->x4, ex->x2 + ey->x4);
      ex->y4= max (ex->y4, ey->y4);
      ex->x2 += ey->x2;
    }
  }
}

void
compound_font_rep::draw (renderer ren, string s, SI x, SI y) {
  int i=0, n= N(s);
  while (i < n) {
    int nr;
    string r= s;
    metric ey;
    advance (s, i, r, nr);
    if (nr >= 0) {
      fn[nr]->draw (ren, r, x, y);
      if (i < n) {
	fn[nr]->get_extents (r, ey);
	x += ey->x2;
      }
    }
  }
}

/******************************************************************************
* Other routines for fonts
******************************************************************************/

glyph
compound_font_rep::get_glyph (string s) {
  int i=0, n= N(s), nr;
  if (n == 0) return fn[0]->get_glyph (s);
  string r= s;
  advance (s, i, r, nr);
  if (nr<0) return glyph ();
  return fn[nr]->get_glyph (r);
}

double
compound_font_rep::get_left_slope  (string s) {
  int i=0, n= N(s), nr;
  if (n == 0) return fn[0]->get_left_slope (s);
  string r= s;
  advance (s, i, r, nr);
  nr= max (nr, 0);
  return fn[nr]->get_left_slope (r);
}

double
compound_font_rep::get_right_slope (string s) {
  int i=0, n= N(s), nr;
  if (n == 0) return fn[0]->get_right_slope (s);
  string r= s;
  while (i<n) advance (s, i, r, nr);
  nr= max (nr, 0);
  return fn[nr]->get_right_slope (r);
}

SI
compound_font_rep::get_left_correction  (string s) {
  int i=0, n= N(s), nr;
  if (n == 0) return fn[0]->get_left_correction (s);
  string r= s;
  advance (s, i, r, nr);
  nr= max (nr, 0);
  return fn[nr]->get_left_correction (r);
}

SI
compound_font_rep::get_right_correction (string s) {
  int i=0, n= N(s), nr;
  if (n == 0) return fn[0]->get_right_correction (s);
  string r= s;
  while (i<n) advance (s, i, r, nr);
  nr= max (nr, 0);
  return fn[nr]->get_right_correction (r);
}

/******************************************************************************
* User interface
******************************************************************************/

font
compound_font (scheme_tree def) {
  string name= tree_to_scheme (def);
  if (font::instances->contains (name))
    return font (name);
  array<font> fn (N(def));
  fn[0]= find_font (def[0][1]);
  if (is_nil (fn[0])) return font ();
  return make (font, name, tm_new<compound_font_rep> (name, def, fn));
}