text: /* $XTermId: doublechr.c,v 1.43 2005/08/05 01:25:39 tom Exp $ */
  
  /*
   * $XFree86: xc/programs/xterm/doublechr.c,v 3.17 2005/08/05 01:25:39 dickey Exp $
   */
  
  /************************************************************
  
  Copyright 1997-2004,2005 by Thomas E. Dickey
  
                          All Rights Reserved
  
  Permission is hereby granted, free of charge, to any person obtaining a
  copy of this software and associated documentation files (the
  "Software"), to deal in the Software without restriction, including
  without limitation the rights to use, copy, modify, merge, publish,
  distribute, sublicense, and/or sell copies of the Software, and to
  permit persons to whom the Software is furnished to do so, subject to
  the following conditions:
  
  The above copyright notice and this permission notice shall be included
  in all copies or substantial portions of the Software.
  
  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. 
  IN NO EVENT SHALL THE ABOVE LISTED COPYRIGHT HOLDER(S) BE LIABLE FOR ANY
  CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  
  Except as contained in this notice, the name(s) of the above copyright
  holders shall not be used in advertising or otherwise to promote the
  sale, use or other dealings in this Software without prior written
  authorization.
  
  ********************************************************/
  
  #include <xterm.h>
  #include <data.h>
  #include <fontutils.h>
  
  #include <assert.h>
  
  /*
   * The first column is all that matters for double-size characters (since the
   * controls apply to a whole line).  However, it's easier to maintain the
   * information for special fonts by writing to all cells.
   */
  #define curChrSet SCRN_BUF_CSETS(screen, screen->cur_row)[0]
  
  #if OPT_DEC_CHRSET
  static void
  repaint_line(unsigned newChrSet)
  {
      register TScreen *screen = &term->screen;
      int curcol = screen->cur_col;
      int currow = screen->cur_row;
      unsigned len = MaxCols(screen);
      int width = len;
      unsigned oldChrSet = SCRN_BUF_CSETS(screen, currow)[0];
  
      assert(width > 0);
  
      /*
       * Ignore repetition.
       */
      if (oldChrSet == newChrSet)
  	return;
  
      TRACE(("repaint_line(%2d,%2d) (%d)\n", currow, screen->cur_col, newChrSet));
      HideCursor();
  
      /* If switching from single-width, keep the cursor in the visible part
       * of the line.
       */
      if (CSET_DOUBLE(newChrSet)) {
  	width /= 2;
  	if (curcol > width)
  	    curcol = width;
      }
  
      /*
       * ScrnRefresh won't paint blanks for us if we're switching between a
       * single-size and double-size font.  So we paint our own.
       */
      if (CSET_DOUBLE(oldChrSet) != CSET_DOUBLE(newChrSet)) {
  	ClearCurBackground(screen,
  			   CursorY(screen, currow),
  			   CurCursorX(screen, currow, 0),
  			   (unsigned) FontHeight(screen),
  			   len * CurFontWidth(screen, currow));
      }
  
      /* FIXME: do VT220 softchars allow double-sizes? */
      memset(SCRN_BUF_CSETS(screen, currow), (Char) newChrSet, len);
  
      set_cur_col(screen, 0);
      ScrnUpdate(screen, currow, 0, 1, (int) len, True);
      set_cur_col(screen, curcol);
  }
  #endif
  
  /*
   * Set the line to double-height characters.  The 'top' flag denotes whether
   * we'll be using it for the top (true) or bottom (false) of the line.
   */
  void
  xterm_DECDHL(Bool top)
  {
  #if OPT_DEC_CHRSET
      repaint_line((unsigned) (top ? CSET_DHL_TOP : CSET_DHL_BOT));
  #endif
  }
  
  /*
   * Set the line to single-width characters (the normal state).
   */
  void
  xterm_DECSWL(void)
  {
  #if OPT_DEC_CHRSET
      repaint_line(CSET_SWL);
  #endif
  }
  
  /*
   * Set the line to double-width characters
   */
  void
  xterm_DECDWL(void)
  {
  #if OPT_DEC_CHRSET
      repaint_line(CSET_DWL);
  #endif
  }
  
  #if OPT_DEC_CHRSET
  static void
  discard_font(TScreen * screen, XTermFonts * data)
  {
      TRACE(("discard_font chrset=%d %s\n", data->chrset,
  	   (data->fn != 0) ? data->fn : "<no-name>"));
  
      data->chrset = 0;
      data->flags = 0;
      if (data->gc != 0) {
  	XFreeGC(screen->display, data->gc);
  	data->gc = 0;
      }
      if (data->fn != 0) {
  	free(data->fn);
  	data->fn = 0;
      }
      if (data->fs != 0) {
  	XFreeFont(screen->display, data->fs);
  	data->fs = 0;
      }
  }
  
  int
  xterm_Double_index(unsigned chrset, unsigned flags)
  {
      int n;
      TScreen *screen = &term->screen;
      XTermFonts *data = screen->double_fonts;
  
      flags &= BOLD;
      TRACE(("xterm_Double_index chrset=%#x, flags=%#x\n", chrset, flags));
  
      for (n = 0; n < screen->fonts_used; n++) {
  	if (data[n].chrset == chrset
  	    && data[n].flags == flags) {
  	    if (n != 0) {
  		XTermFonts save;
  		TRACE(("...xterm_Double_index -> %d (OLD:%d)\n", n, screen->fonts_used));
  		save = data[n];
  		while (n > 0) {
  		    data[n] = data[n - 1];
  		    n--;
  		}
  		data[n] = save;
  	    }
  	    return n;
  	}
      }
  
      /* Not, found, push back existing fonts and create a new entry */
      if (screen->fonts_used >= screen->cache_doublesize) {
  	TRACE(("...xterm_Double_index: discard oldest\n"));
  	discard_font(screen, &(data[screen->fonts_used - 1]));
      } else {
  	screen->fonts_used += 1;
      }
      for (n = screen->fonts_used; n > 0; n--)
  	data[n] = data[n - 1];
  
      TRACE(("...xterm_Double_index -> (NEW:%d)\n", screen->fonts_used));
  
      data[0].chrset = chrset;
      data[0].flags = flags;
      data[0].fn = 0;
      data[0].fs = 0;
      data[0].gc = 0;
      return 0;
  }
  
  /*
   * Lookup/cache a GC for the double-size character display.  We save up to
   * NUM_CHRSET values.
   */
  GC
  xterm_DoubleGC(unsigned chrset, unsigned flags, GC old_gc)
  {
      XGCValues gcv;
      register TScreen *screen = &term->screen;
      unsigned long mask = (GCForeground | GCBackground | GCFont);
      int n;
      char *name;
      XTermFonts *data;
  
      if ((name = xtermSpecialFont(screen, flags, chrset)) == 0)
  	return 0;
  
      n = xterm_Double_index(chrset, flags);
      data = &(screen->double_fonts[n]);
      if (data->fn != 0) {
  	if (!strcmp(data->fn, name)) {
  	    if (data->fs != 0) {
  		XCopyGC(screen->display, old_gc, (unsigned long) (~GCFont), data->gc);
  		return data->gc;
  	    }
  	}
  	discard_font(screen, data);
  	data->chrset = chrset;
  	data->flags = flags & BOLD;
      }
      data->fn = name;
  
      TRACE(("xterm_DoubleGC %s %d: %s\n", flags & BOLD ? "BOLD" : "NORM", n, name));
  
      if ((data->fs = XLoadQueryFont(screen->display, name)) == 0) {
  	/* Retry with * in resolutions */
  	char *nname = xtermSpecialFont(screen, flags | NORESOLUTION, chrset);
  
  	if (!nname)
  	    return 0;
  	if ((data->fs = XLoadQueryFont(screen->display, nname)) == 0) {
  	    XtFree(nname);
  	    return 0;
  	}
  	XtFree(name);
  	data->fn = nname;
      }
  
      TRACE(("-> OK\n"));
  
      gcv.graphics_exposures = TRUE;	/* default */
      gcv.font = data->fs->fid;
      gcv.foreground = T_COLOR(screen, TEXT_FG);
      gcv.background = T_COLOR(screen, TEXT_BG);
  
      data->gc = XCreateGC(screen->display, VWindow(screen), mask, &gcv);
      XCopyGC(screen->display, old_gc, (unsigned long) (~GCFont), data->gc);
      return data->gc;
  }
  #endif
  