fl_font_x.cxx

//
// "$Id$"
//
// Standard X11 font selection code for the Fast Light Tool Kit (FLTK).
//
// Copyright 1998-2016 by Bill Spitzak and others.
//
// This library is free software. Distribution and use rights are outlined in
// the file "COPYING" which should have been included with this file.  If this
// file is missing or damaged, see the license at:
//
//     http://www.fltk.org/COPYING.php
//
// Please report all bugs and problems on the following page:
//
//     http://www.fltk.org/str.php
//
#ifndef FL_DOXYGEN
 
Fl_Font_Descriptor::Fl_Font_Descriptor(const char* name) {
  font = XCreateUtf8FontStruct(fl_display, name);
  if (!font) {
    Fl::warning("bad font: %s", name);
    font = XCreateUtf8FontStruct(fl_display, "fixed");
  }
#  if HAVE_GL
  listbase = 0;
  for (int u = 0; u < 64; u++) glok[u] = 0;
#  endif
}
 
Fl_XFont_On_Demand fl_xfont;
 
Fl_Font_Descriptor::~Fl_Font_Descriptor() {
#  if HAVE_GL
// Delete list created by gl_draw().  This is not done by this code
// as it will link in GL unnecessarily.  There should be some kind
// of "free" routine pointer, or a subclass?
// if (listbase) {
//  int base = font->min_char_or_byte2;
//  int size = font->max_char_or_byte2-base+1;
//  int base = 0; int size = 256;
//  glDeleteLists(listbase+base,size);
// }
#  endif
  if (this == fl_graphics_driver->font_descriptor()) {
    fl_graphics_driver->font_descriptor(NULL);
    fl_xfont = 0;
  }
  XFreeUtf8FontStruct(fl_display, font);
}
 
 
// WARNING: if you add to this table, you must redefine FL_FREE_FONT
// in Enumerations.H & recompile!!
static Fl_Fontdesc built_in_table[] = {
{"-*-helvetica-medium-r-normal--*"},
{"-*-helvetica-bold-r-normal--*"},
{"-*-helvetica-medium-o-normal--*"},
{"-*-helvetica-bold-o-normal--*"},
{"-*-courier-medium-r-normal--*"},
{"-*-courier-bold-r-normal--*"},
{"-*-courier-medium-o-normal--*"},
{"-*-courier-bold-o-normal--*"},
{"-*-times-medium-r-normal--*"},
{"-*-times-bold-r-normal--*"},
{"-*-times-medium-i-normal--*"},
{"-*-times-bold-i-normal--*"},
{"-*-symbol-*"},
{"-*-lucidatypewriter-medium-r-normal-sans-*"},
{"-*-lucidatypewriter-bold-r-normal-sans-*"},
{"-*-*zapf dingbats-*"}
};
 
Fl_Fontdesc* fl_fonts = built_in_table;
 
#define MAXSIZE 32767
 
// return dash number N, or pointer to ending null if none:
const char* fl_font_word(const char* p, int n) {
  while (*p) {if (*p=='-') {if (!--n) break;} p++;}
  return p;
}
 
// return a pointer to a number we think is "point size":
char* fl_find_fontsize(char* name) {
  char* c = name;
  // for standard x font names, try after 7th dash:
  if (*c == '-') {
    c = (char*)fl_font_word(c,7);
    if (*c++ && isdigit(*c)) return c;
    return 0; // malformed x font name?
  }
  char* r = 0;
  // find last set of digits:
  for (c++;* c; c++)
    if (isdigit(*c) && !isdigit(*(c-1))) r = c;
  return r;
}
 
//const char* fl_encoding = "iso8859-1";
const char* fl_encoding = "iso10646-1";
 
// return true if this matches fl_encoding:
int fl_correct_encoding(const char* name) {
  if (*name != '-') return 0;
  const char* c = fl_font_word(name,13);
  return (*c++ && !strcmp(c,fl_encoding));
}
 
static const char *find_best_font(const char *fname, int size) {
  int cnt;
  static char **list = NULL;
// locate or create an Fl_Font_Descriptor for a given Fl_Fontdesc and size:
  if (list) XFreeFontNames(list);
  list = XListFonts(fl_display, fname, 100, &cnt);
  if (!list) return "fixed";
 
  // search for largest <= font size:
  char* name = list[0]; int ptsize = 0;   // best one found so far
  int matchedlength = 32767;
  static char namebuffer[1024];           // holds scalable font name
  int found_encoding = 0;
  int m = cnt; if (m<0) m = -m;
  for (int n=0; n < m; n++) {
    char* thisname = list[n];
    if (fl_correct_encoding(thisname)) {
      if (!found_encoding) ptsize = 0;    // force it to choose this
      found_encoding = 1;
    } else {
      if (found_encoding) continue;
    }
    char* c = (char*)fl_find_fontsize(thisname);
    int thissize = c ? atoi(c) : MAXSIZE;
    int thislength = strlen(thisname);
    if (thissize == size && thislength < matchedlength) {
      // exact match, use it:
      name = thisname;
      ptsize = size;
      matchedlength = thislength;
    } else if (!thissize && ptsize!=size) {
      // whoa!  A scalable font!  Use unless exact match found:
      int l = c-thisname;
      memcpy(namebuffer,thisname,l);
      l += sprintf(namebuffer+l,"%d",size);
      while (*c == '0') c++;
      strcpy(namebuffer+l,c);
      name = namebuffer;
      ptsize = size;
    } else if (!ptsize ||       // no fonts yet
               (thissize < ptsize && ptsize > size) || // current font too big
               (thissize > ptsize && thissize <= size) // current too small
      ) {
      name = thisname;
      ptsize = thissize;
      matchedlength = thislength;
    }
  }
 
//  if (ptsize != size) { // see if we already found this unscalable font:
//    for (f = s->first; f; f = f->next) {
//      if (f->minsize <= ptsize && f->maxsize >= ptsize) {
//      if (f->minsize > size) f->minsize = size;
//      if (f->maxsize < size) f->maxsize = size;
//      return f;
//      }
//    }
//  }
//
//  // okay, we definately have some name, make the font:
//  f = new Fl_Font_Descriptor(name);
//  if (ptsize < size) {f->minsize = ptsize; f->maxsize = size;}
//  else {f->minsize = size; f->maxsize = ptsize;}
//  f->next = s->first;
//  s->first = f;
//  return f;
 
  return name;
}
 
static char *put_font_size(const char *n, int size)
{
        int i = 0;
        char *buf;
        const char *ptr;
        const char *f;
        char *name;
        int nbf = 1;
        name = strdup(n);
        while (name[i]) {
                if (name[i] == ',') {nbf++; name[i] = '\0';}
                i++;
        }
 
        buf = (char*) malloc(nbf * 256);
        buf[0] = '\0';
        ptr = name;
        i = 0;
        while (ptr && nbf > 0) {
                f = find_best_font(ptr, size);
                while (*f) {
                        buf[i] = *f;
                        f++; i++;
                }
                nbf--;
                while (*ptr) ptr++;
                if (nbf) {
                        ptr++;
                        buf[i] = ',';
                        i++;
                }
                while(isspace(*ptr)) ptr++;
        }
        buf[i] = '\0';
        free(name);
        return buf;
}
 
 
char *fl_get_font_xfld(int fnum, int size) {
  Fl_Fontdesc* s = fl_fonts+fnum;
  if (!s->name) s = fl_fonts; // use font 0 if still undefined
  fl_open_display();
  return put_font_size(s->name, size);
}
 
// locate or create an Fl_Font_Descriptor for a given Fl_Fontdesc and size:
static Fl_Font_Descriptor* find(int fnum, int size) {
  char *name;
  Fl_Fontdesc* s = fl_fonts+fnum;
  if (!s->name) s = fl_fonts; // use font 0 if still undefined
  Fl_Font_Descriptor* f;
  for (f = s->first; f; f = f->next)
    if (f->size == size) return f;
  fl_open_display();
 
  name = put_font_size(s->name, size);
  f = new Fl_Font_Descriptor(name);
  f->size = size;
  f->next = s->first;
  s->first = f;
  free(name);
  return f;
}
 
 
// Public interface:
 
void *fl_xftfont = 0;
static GC font_gc;
 
XFontStruct* Fl_XFont_On_Demand::value() {
  return ptr;
}
 
void Fl_Xlib_Graphics_Driver::font(Fl_Font fnum, Fl_Fontsize size) {
  if (fnum==-1) {
    Fl_Graphics_Driver::font(0, 0);
    return;
  }
  if (fnum == Fl_Graphics_Driver::font() && size == Fl_Graphics_Driver::size()) return;
  Fl_Graphics_Driver::font(fnum, size);
  Fl_Font_Descriptor* f = find(fnum, size);
  if (f != this->font_descriptor()) {
    this->font_descriptor(f);
    fl_xfont = f->font->fonts[0];
    font_gc = 0;
  }
}
 
int Fl_Xlib_Graphics_Driver::height() {
  if (font_descriptor()) return font_descriptor()->font->ascent + font_descriptor()->font->descent;
  else return -1;
}
 
int Fl_Xlib_Graphics_Driver::descent() {
  if (font_descriptor()) return font_descriptor()->font->descent;
  else return -1;
}
 
double Fl_Xlib_Graphics_Driver::width(const char* c, int n) {
  if (font_descriptor()) return (double) XUtf8TextWidth(font_descriptor()->font, c, n);
  else return -1;
}
 
double Fl_Xlib_Graphics_Driver::width(unsigned int c) {
  if (font_descriptor()) return (double) XUtf8UcsWidth(font_descriptor()->font, c);
  else return -1;
}
 
void Fl_Xlib_Graphics_Driver::text_extents(const char *c, int n, int &dx, int &dy, int &W, int &H) {
  if (font_gc != fl_gc) {
    if (!font_descriptor()) font(FL_HELVETICA, FL_NORMAL_SIZE);
    font_gc = fl_gc;
    XSetFont(fl_display, fl_gc, font_descriptor()->font->fid);
  }
  int xx, yy, ww, hh;
  xx = yy = ww = hh = 0;
  if (fl_gc) XUtf8_measure_extents(fl_display, fl_window, font_descriptor()->font, fl_gc, &xx, &yy, &ww, &hh, c, n);
 
  W = ww; H = hh; dx = xx; dy = yy;
// This is the safe but mostly wrong thing we used to do...
//  W = 0; H = 0;
//  fl_measure(c, W, H, 0);
//  dx = 0;
//  dy = fl_descent() - H;
}
 
void Fl_Xlib_Graphics_Driver::draw(const char* c, int n, int x, int y) {
  if (font_gc != fl_gc) {
    if (!font_descriptor()) this->font(FL_HELVETICA, FL_NORMAL_SIZE);
    font_gc = fl_gc;
    XSetFont(fl_display, fl_gc, font_descriptor()->font->fid);
  }
  if (fl_gc) XUtf8DrawString(fl_display, fl_window, font_descriptor()->font, fl_gc, x, y, c, n);
}
 
void Fl_Xlib_Graphics_Driver::draw(int angle, const char *str, int n, int x, int y) {
  static char warning = 0; // issue warning only once
  if (!warning && angle != 0) {
    warning = 1;
    fprintf(stderr,
            "libfltk: rotated text not implemented by X backend.\n"
            "  You should use the Xft backend. Check USE_XFT in config.h.\n");
  }
  this->draw(str, n, (int)x, (int)y);
}
 
void Fl_Xlib_Graphics_Driver::rtl_draw(const char* c, int n, int x, int y) {
  if (font_gc != fl_gc) {
    if (!font_descriptor()) this->font(FL_HELVETICA, FL_NORMAL_SIZE);
    font_gc = fl_gc;
  }
  if (fl_gc) XUtf8DrawRtlString(fl_display, fl_window, font_descriptor()->font, fl_gc, x, y, c, n);
}
#endif // FL_DOXYGEN
//
// End of "$Id$".
//