TGFont.cxx

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// @(#)root/gui:$Id$
// Author: Fons Rademakers   20/5/2003
 
/*************************************************************************
 * Copyright (C) 1995-2003, Rene Brun and Fons Rademakers.               *
 * All rights reserved.                                                  *
 *                                                                       *
 * For the licensing terms see $ROOTSYS/LICENSE.                         *
 * For the list of contributors see $ROOTSYS/README/CREDITS.             *
 *************************************************************************/
/**************************************************************************
 
    This source is based on Xclass95, a Win95-looking GUI toolkit.
    Copyright (C) 1996, 1997 David Barth, Ricky Ralston, Hector Peraza.
 
    Xclass95 is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.
 
**************************************************************************/
 
 
/** \class TGFont
    \ingroup guiwidgets
 
Encapsulate fonts used in the GUI system.
 
 
\class TGFontPool
\ingroup guiwidgets
 
Provides a pool of fonts.
 
 
\class TGTextLayout
\ingroup guiwidgets
 
Is used to keep track of string  measurement
information when  using the text layout facilities.
It can be displayed with respect to any origin.
 
*/
 
 
#include "TGFont.h"
#include "TGClient.h"
#include "THashTable.h"
#include "TVirtualX.h"
#include "TObjString.h"
#include "TGWidget.h"
#include "TROOT.h"
#include "TError.h"
#include "TMath.h"
#include "strlcpy.h"
#include "snprintf.h"
 
#include <cerrno>
#include <cstdlib>
#include <climits>
#include <iostream>
 
 
 
#define FONT_FAMILY     0
#define FONT_SIZE       1
#define FONT_WEIGHT     2
#define FONT_SLANT      3
#define FONT_UNDERLINE  4
#define FONT_OVERSTRIKE 5
#define FONT_NUMFIELDS  6
 
// The following defines specify the meaning of the fields in a fully
// qualified XLFD.
 
#define XLFD_FOUNDRY        0
#define XLFD_FAMILY         1
#define XLFD_WEIGHT         2
#define XLFD_SLANT          3
#define XLFD_SETWIDTH       4
#define XLFD_ADD_STYLE      5
#define XLFD_PIXEL_SIZE     6
#define XLFD_POINT_SIZE     7
#define XLFD_RESOLUTION_X   8
#define XLFD_RESOLUTION_Y   9
#define XLFD_SPACING        10
#define XLFD_AVERAGE_WIDTH  11
#define XLFD_REGISTRY       12
#define XLFD_ENCODING       13
#define XLFD_NUMFIELDS      14   // Number of fields in XLFD.
 
 
// A LayoutChunk_t represents a contiguous range of text that can be measured
// and displayed by low-level text calls. In general, chunks will be
// delimited by newlines and tabs. Low-level, platform-specific things
// like kerning and non-integer character widths may occur between the
// characters in a single chunk, but not between characters in different
// chunks.
 
struct LayoutChunk_t {
 
   const char *fStart;     // Pointer to simple string to be displayed.
                           // This is a pointer into the TGTextLayout's
                           // string.
   Int_t fNumChars;        // The number of characters in this chunk.
   Int_t fNumDisplayChars; // The number of characters to display when
                           // this chunk is displayed. Can be less than
                           // numChars if extra space characters were
                           // absorbed by the end of the chunk. This
                           // will be < 0 if this is a chunk that is
                           // holding a tab or newline.
   Int_t fX;               // The x origin and
   Int_t fY;               // the y origin of the first character in this
                           // chunk with respect to the upper-left hand
                           // corner of the TGTextLayout.
   Int_t fTotalWidth;      // Width in pixels of this chunk. Used
                           // when hit testing the invisible spaces at
                           // the end of a chunk.
   Int_t fDisplayWidth;    // Width in pixels of the displayable
                           // characters in this chunk. Can be less than
                           // width if extra space characters were
                           // absorbed by the end of the chunk.
};
 
 
// The following structure is used to return attributes when parsing an
// XLFD. The extra information is used to find the closest matching font.
 
struct XLFDAttributes_t {
   FontAttributes_t fFA; // Standard set of font attributes.
   const char *fFoundry; // The foundry of the font.
   Int_t fSlant;         // The tristate value for the slant
   Int_t fSetwidth;      // The proportionate width
   Int_t fCharset;       // The character set encoding (the glyph family).
   Int_t fEncoding;      // Variations within a charset for the glyphs above character 127.
 
   XLFDAttributes_t() :  // default constructor
      fFA(),
      fFoundry(0),
      fSlant(0),
      fSetwidth(0),
      fCharset(0),
      fEncoding(0) { }
};
 
 
// The following data structure is used to keep track of the font attributes
// for each named font that has been defined. The named font is only deleted
// when the last reference to it goes away.
 
class TNamedFont : public TObjString, public TRefCnt {
public:
   Int_t            fDeletePending; // Non-zero if font should be deleted when last reference goes away.
   FontAttributes_t fFA;            // Desired attributes for named font.
};
 
// enums
enum EFontSpacing { kFontProportional = 0,
                    kFontFixed = 1,
                    kFontMono = 1,
                    kFontCharcell = 2 };
 
enum EFontSetWidth { kFontSWNormal = 0,
                     kFontSWCondence = 1,
                     kFontSWExpand = 2,
                     kFontSWUnknown = 3 };
 
enum EFontCharset { kFontCSNormal = 0,
                    kFontCSSymbol = 1,
                    kFontCSOther = 2 };
 
 
// Possible values for entries in the "types" field in a TGFont structure,
// which classifies the types of all characters in the given font. This
// information is used when measuring and displaying characters.
//
// kCharNormal:         Standard character.
// kCharReplace:        This character doesn't print: instead of displaying
//                      character, display a replacement sequence like "\n"
//                      (for those characters where ANSI C defines such a
//                      sequence) or a sequence of the form "\xdd" where dd
//                      is the hex equivalent of the character.
// kCharSkip:           Don't display anything for this character. This is
//                      only used where the font doesn't contain all the
//                      characters needed to generate replacement sequences.
enum ECharType { kCharNormal, kCharReplace, kCharSkip };
 
 
// The following structures are used as two-way maps between the values for
// the fields in the FontAttributes_t structure and the strings used when
// parsing both option-value format and style-list format font name strings.
 
struct FontStateMap_t { Int_t fNumKey; const char *fStrKey; };
 
static const FontStateMap_t gWeightMap[] = {
   { kFontWeightNormal,  "normal" },
   { kFontWeightBold,    "bold"   },
   { kFontWeightUnknown, 0        }
};
 
static const FontStateMap_t gSlantMap[] = {
   { kFontSlantRoman,   "roman"  },
   { kFontSlantItalic,  "italic" },
   { kFontSlantUnknown, 0        }
};
 
static const FontStateMap_t gUnderlineMap[] = {
   { 1, "underline" },
   { 0, 0           }
};
 
static const FontStateMap_t gOverstrikeMap[] = {
   { 1, "overstrike" },
   { 0, 0            }
};
 
// The following structures are used when parsing XLFD's into a set of
// FontAttributes_t.
 
static const FontStateMap_t gXlfdgWeightMap[] = {
   { kFontWeightNormal, "normal"   },
   { kFontWeightNormal, "medium"   },
   { kFontWeightNormal, "book"     },
   { kFontWeightNormal, "light"    },
   { kFontWeightBold,   "bold"     },
   { kFontWeightBold,   "demi"     },
   { kFontWeightBold,   "demibold" },
   { kFontWeightNormal,  0         }  // Assume anything else is "normal".
};
 
static const FontStateMap_t gXlfdSlantMap[] = {
   { kFontSlantRoman,   "r"  },
   { kFontSlantItalic,  "i"  },
   { kFontSlantOblique, "o"  },
   { kFontSlantRoman,   0    }  // Assume anything else is "roman".
};
 
static const FontStateMap_t gXlfdSetwidthMap[] = {
   { kFontSWNormal,   "normal"        },
   { kFontSWCondence, "narrow"        },
   { kFontSWCondence, "semicondensed" },
   { kFontSWCondence, "condensed"     },
   { kFontSWUnknown,  0               }
};
 
static const FontStateMap_t gXlfdCharsetMap[] = {
   { kFontCSNormal, "iso8859" },
   { kFontCSSymbol, "adobe"   },
   { kFontCSSymbol, "sun"     },
   { kFontCSOther,  0         }
};
 
 
// Characters used when displaying control sequences.
 
static char gHexChars[] = "0123456789abcdefxtnvr\\";
 
 
// The following table maps some control characters to sequences like '\n'
// rather than '\x10'. A zero entry in the table means no such mapping
// exists, and the table only maps characters less than 0x10.
 
static char gMapChars[] = {
   0, 0, 0, 0, 0, 0, 0, 'a', 'b', 't', 'n', 'v', 'f', 'r', 0
};
 
static int GetControlCharSubst(int c, char buf[4]);
 
 
////////////////////////////////////////////////////////////////////////////////
/// Delete font.
 
TGFont::~TGFont()
{
   if (fFontStruct) {
      gVirtualX->DeleteFont(fFontStruct);
   }
}
 
////////////////////////////////////////////////////////////////////////////////
/// Get font metrics.
 
void TGFont::GetFontMetrics(FontMetrics_t *m) const
{
   if (!m) {
      Error("GetFontMetrics", "argument may not be 0");
      return;
   }
 
   *m = fFM;
   m->fLinespace = fFM.fAscent + fFM.fDescent;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Not inline due to a bug in g++ 2.96 20000731 (Red Hat Linux 7.0)
 
FontStruct_t TGFont::operator()() const
{
   return fFontStruct;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Print font info.
 
void TGFont::Print(Option_t *option) const
{
   TString opt = option;
 
   if ((opt == "full") && fNamedHash) {
      Printf("TGFont: %s, %s, ref cnt = %u",
              fNamedHash->GetName(),
              fFM.fFixed ? "fixed" : "prop", References());
   } else {
      Printf("TGFont: %s, %s, ref cnt = %u", fName.Data(),
              fFM.fFixed ? "fixed" : "prop", References());
   }
}
 
////////////////////////////////////////////////////////////////////////////////
/// Return the name of the corresponding Postscript font for this TGFont.
///
/// The return value is the pointsize of the TGFont. The name of the
/// Postscript font is appended to ds.
///
/// If the font does not exist on the printer, the print job will fail at
/// print time. Given a "reasonable" Postscript printer, the following
/// TGFont font families should print correctly:
///
///     Avant Garde, Arial, Bookman, Courier, Courier New, Geneva,
///     Helvetica, Monaco, New Century Schoolbook, New York,
///     Palatino, Symbol, Times, Times New Roman, Zapf Chancery,
///     and Zapf Dingbats.
///
/// Any other TGFont font families may not print correctly because the
/// computed Postscript font name may be incorrect.
///
/// dst -- Pointer to an initialized TString object to which the name of the
///        Postscript font that corresponds to the font will be appended.
 
Int_t TGFont::PostscriptFontName(TString *dst) const
{
   const char *family;
   TString weightString;
   TString slantString;
   char *src, *dest;
   Int_t upper, len;
 
   len = dst->Length();
 
   // Convert the case-insensitive TGFont family name to the
   // case-sensitive Postscript family name. Take out any spaces and
   // capitalize the first letter of each word.
 
   family = fFA.fFamily;
   if (strncasecmp(family, "itc ", 4) == 0) {
      family = family + 4;
   }
   if ((strcasecmp(family, "Arial") == 0)
       || (strcasecmp(family, "Geneva") == 0)) {
      family = "Helvetica";
   } else if ((strcasecmp(family, "Times New Roman") == 0)
              || (strcasecmp(family, "New York") == 0)) {
      family = "Times";
   } else if ((strcasecmp(family, "Courier New") == 0)
              || (strcasecmp(family, "Monaco") == 0)) {
      family = "Courier";
   } else if (strcasecmp(family, "AvantGarde") == 0) {
      family = "AvantGarde";
   } else if (strcasecmp(family, "ZapfChancery") == 0) {
      family = "ZapfChancery";
   } else if (strcasecmp(family, "ZapfDingbats") == 0) {
      family = "ZapfDingbats";
   } else {
 
      // Inline, capitalize the first letter of each word, lowercase the
      // rest of the letters in each word, and then take out the spaces
      // between the words. This may make the TString shorter, which is
      // safe to do.
 
      dst->Append(family);
 
      src = dest = (char*)dst->Data() + len;
      upper = 1;
      for (; *src != '\0'; src++, dest++) {
         while (isspace(UChar_t(*src))) {
            src++;
            upper = 1;
         }
         *dest = *src;
         if ((upper != 0) && (islower(UChar_t(*src)))) {
            *dest = toupper(UChar_t(*src));
         }
         upper = 0;
      }
      *dest = '\0';
      //dst->SetLength(dest - dst->GetString()); // dst->ResetLength(); may be better
      family = (char *) dst->Data() + len;
   }
   if (family != (char *) dst->Data() + len) {
      dst->Append(family);
      family = (char *) dst->Data() + len;
   }
   if (strcasecmp(family, "NewCenturySchoolbook") == 0) {
//      dst->SetLength(len);
      dst->Append("NewCenturySchlbk");
      family = (char *) dst->Data() + len;
   }
 
   // Get the string to use for the weight.
 
   weightString = "";
   if (fFA.fWeight == kFontWeightNormal) {
      if (strcmp(family, "Bookman") == 0) {
         weightString = "Light";
      } else if (strcmp(family, "AvantGarde") == 0) {
         weightString = "Book";
      } else if (strcmp(family, "ZapfChancery") == 0) {
         weightString = "Medium";
      }
   } else {
      if ((strcmp(family, "Bookman") == 0)
           || (strcmp(family, "AvantGarde") == 0)) {
         weightString = "Demi";
      } else {
         weightString = "Bold";
      }
   }
 
   // Get the string to use for the slant.
 
   slantString = "";
   if (fFA.fSlant == kFontSlantRoman) {
      ;
   } else {
      if ((strcmp(family, "Helvetica") == 0)
           || (strcmp(family, "Courier") == 0)
           || (strcmp(family, "AvantGarde") == 0)) {
         slantString = "Oblique";
      } else {
         slantString = "Italic";
      }
   }
 
   // The string "Roman" needs to be added to some fonts that are not bold
   // and not italic.
 
   if ((slantString.IsNull()) && (weightString.IsNull())) {
      if ((strcmp(family, "Times") == 0)
           || (strcmp(family, "NewCenturySchlbk") == 0)
           || (strcmp(family, "Palatino") == 0)) {
         dst->Append("-Roman");
      }
   } else {
      dst->Append("-");
      if (!weightString.IsNull()) dst->Append(weightString);
      if (!slantString.IsNull()) dst->Append(slantString);
   }
 
   return fFA.fPointsize;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Determine the number of characters from the string that will fit in the
/// given horizontal span. The measurement is done under the assumption that
/// DrawChars() will be used to actually display the characters.
///
/// The return value is the number of characters from source that fit into
/// the span that extends from 0 to maxLength. *length is filled with the
/// x-coordinate of the right edge of the last character that did fit.
///
/// source    -- Characters to be displayed. Need not be '\0' terminated.
/// numChars  -- Maximum number of characters to consider from source string.
/// maxLength -- If > 0, maxLength specifies the longest permissible line
///              length; don't consider any character that would cross this
///              x-position. If <= 0, then line length is unbounded and the
///              flags argument is ignored.
/// flags     -- Various flag bits OR-ed together:
///              TEXT_PARTIAL_OK means include the last char which only
///              partially fit on this line.
///              TEXT_WHOLE_WORDS means stop on a word boundary, if possible.
///              TEXT_AT_LEAST_ONE means return at least one character even
///              if no characters fit.
/// *length   -- Filled with x-location just after the terminating character.
 
Int_t TGFont::MeasureChars(const char *source, Int_t numChars, Int_t maxLength,
                          Int_t flags, Int_t *length) const
{
   const char *p;    // Current character.
   const char *term; // Pointer to most recent character that may legally be a terminating character.
   Int_t termX;      // X-position just after term.
   Int_t curX;       // X-position corresponding to p.
   Int_t newX;       // X-position corresponding to p+1.
   Int_t c, sawNonSpace;
 
   if (!numChars) {
      *length = 0;
      return 0;
   }
   if (maxLength <= 0) {
      maxLength = INT_MAX;
   }
   newX = curX = termX = 0;
   p = term = source;
   sawNonSpace = !isspace(UChar_t(*p));
 
   // Scan the input string one character at a time, calculating width.
 
   for (c = UChar_t(*p);;) {
      newX += fWidths[c];
      if (newX > maxLength) {
         break;
      }
      curX = newX;
      numChars--;
      p++;
      if (!numChars) {
         term = p;
         termX = curX;
         break;
      }
      c = UChar_t(*p);
      if (isspace(c)) {
         if (sawNonSpace) {
            term = p;
            termX = curX;
            sawNonSpace = 0;
         }
      } else {
         sawNonSpace = 1;
      }
   }
 
   // P points to the first character that doesn't fit in the desired
   // span. Use the flags to figure out what to return.
 
   if ((flags & kTextPartialOK) && (numChars > 0) && (curX < maxLength)) {
 
      // Include the first character that didn't quite fit in the desired
      // span. The width returned will include the width of that extra
      // character.
 
      numChars--;
      curX = newX;
      p++;
   }
   if ((flags & kTextAtLeastOne) && (term == source) && (numChars > 0)) {
      term = p;
      termX = curX;
      if (term == source) {
         term++;
         termX = newX;
      }
   } else if ((numChars == 0) || !(flags & kTextWholeWords)) {
      term = p;
      termX = curX;
   }
   *length = termX;
 
   return term - source;
}
 
////////////////////////////////////////////////////////////////////////////////
/// A wrapper function for the more complicated interface of MeasureChars.
/// Computes how much space the given simple string needs.
///
/// The return value is the width (in pixels) of the given string.
///
/// string   -- String whose width will be computed.
/// numChars -- Number of characters to consider from string, or < 0 for
///             strlen().
 
Int_t TGFont::TextWidth(const char *string, Int_t numChars) const
{
   Int_t width;
 
   if (numChars < 0) {
      numChars = strlen(string);
   }
   MeasureChars(string, numChars, 0, 0, &width);
 
   return width;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Return text width in pixels
 
Int_t TGFont::XTextWidth(const char *string, Int_t numChars) const
{
   int width;
 
   if (numChars < 0) {
      numChars = strlen(string);
   }
   width = gVirtualX->TextWidth(fFontStruct, string, numChars);
 
   return width;
}
 
////////////////////////////////////////////////////////////////////////////////
/// This procedure draws an underline for a given range of characters in a
/// given string. It doesn't draw the characters (which are assumed to have
/// been displayed previously); it just draws the underline. This procedure
/// would mainly be used to quickly underline a few characters without having
/// to construct an underlined font. To produce properly underlined text, the
/// appropriate underlined font should be constructed and used.
///
/// dst       -- Window or pixmap in which to draw.
/// gc        -- Graphics context for actually drawing line.
/// string    -- String containing characters to be underlined or overstruck.
/// x, y      -- Coordinates at which first character of string is drawn.
/// firstChar -- Index of first character.
/// lastChar  -- Index of one after the last character.
 
void TGFont::UnderlineChars(Drawable_t dst, GContext_t gc,
                            const char *string, Int_t x, Int_t y,
                            Int_t firstChar, Int_t lastChar) const
{
   Int_t startX, endX;
 
   MeasureChars(string, firstChar, 0, 0, &startX);
   MeasureChars(string, lastChar, 0, 0, &endX);
 
   gVirtualX->FillRectangle(dst, gc, x + startX, y + fUnderlinePos,
                            (UInt_t) (endX - startX),
                            (UInt_t) fUnderlineHeight);
}
 
////////////////////////////////////////////////////////////////////////////////
/// Computes the amount of screen space needed to display a multi-line,
/// justified string of text. Records all the measurements that were done
/// to determine to size and positioning of the individual lines of text;
/// this information can be used by the TGTextLayout::DrawText() procedure
/// to display the text quickly (without remeasuring it).
///
/// This procedure is useful for simple widgets that want to display
/// single-font, multi-line text and want TGFont to handle the details.
///
/// The return value is a TGTextLayout token that holds the measurement
/// information for the given string. The token is only valid for the given
/// string. If the string is freed, the token is no longer valid and must
/// also be deleted.
///
/// The dimensions of the screen area needed to display the text are stored
/// in *width and *height.
///
/// string     -- String whose dimensions are to be computed.
/// numChars   -- Number of characters to consider from string, or < 0 for
///               strlen().
/// wrapLength -- Longest permissible line length, in pixels. <= 0 means no
///               automatic wrapping: just let lines get as long as needed.
/// justify    -- How to justify lines.
/// flags      -- Flag bits OR-ed together. kTextIgnoreTabs means that tab
///               characters should not be expanded. kTextIgnoreNewlines
///               means that newline characters should not cause a line break.
/// width      -- Filled with width of string.
/// height     -- Filled with height of string.
 
TGTextLayout *TGFont::ComputeTextLayout(const char *string, Int_t numChars,
                                        Int_t wrapLength, Int_t justify, Int_t flags,
                                        UInt_t *width, UInt_t *height) const
{
   const char *start, *end, *special;
   Int_t n, y=0, charsThisChunk, maxChunks;
   Int_t baseline, h, curX, newX, maxWidth;
   TGTextLayout *layout;
   LayoutChunk_t *chunk;
 
#define MAX_LINES 50
   Int_t staticLineLengths[MAX_LINES];
   Int_t *lineLengths;
   Int_t maxLines, curLine, layoutHeight;
 
   lineLengths = staticLineLengths;
   maxLines = MAX_LINES;
 
   h = fFM.fAscent + fFM.fDescent;
 
   if (numChars < 0) {
      numChars = strlen(string);
   }
   maxChunks = 0;
 
   layout = new TGTextLayout;
   layout->fFont = this;
   layout->fString = string;
   layout->fNumChunks = 0;
   layout->fChunks = 0;
 
   baseline = fFM.fAscent;
   maxWidth = 0;
 
   // Divide the string up into simple strings and measure each string.
 
   curX = 0;
 
   end = string + numChars;
   special = string;
 
   flags &= kTextIgnoreTabs | kTextIgnoreNewlines;
   flags |= kTextWholeWords | kTextAtLeastOne;
   curLine = 0;
 
   for (start = string; start < end;) {
      if (start >= special) {
         // Find the next special character in the string.
 
         for (special = start; special < end; special++) {
            if (!(flags & kTextIgnoreNewlines)) {
               if ((*special == '\n') || (*special == '\r')) {
                  break;
               }
            }
            if (!(flags & kTextIgnoreTabs)) {
               if (*special == '\t') {
                  break;
               }
            }
         }
      }
 
      // Special points at the next special character (or the end of the
      // string). Process characters between start and special.
 
      chunk = 0;
      if (start < special) {
         charsThisChunk = MeasureChars(start, special - start,
                                       wrapLength - curX, flags, &newX);
         newX += curX;
         flags &= ~kTextAtLeastOne;
         if (charsThisChunk > 0) {
            chunk = NewChunk(layout, &maxChunks, start,
                             charsThisChunk, curX, newX, baseline);
 
            start += charsThisChunk;
            curX = newX;
         }
      }
      if ((start == special) && (special < end)) {
         // Handle the special character.
         LayoutChunk_t *newchunk = 0;
 
         chunk = 0;
         if (*special == '\t') {
            newX = curX + fTabWidth;
            newX -= newX % fTabWidth;
            newchunk = NewChunk(layout, &maxChunks, start, 1, curX, newX, baseline);
            if (newchunk) newchunk->fNumDisplayChars = -1;
            start++;
            if ((start < end) && ((wrapLength <= 0) || (newX <= wrapLength))) {
 
               // More chars can still fit on this line.
 
               curX = newX;
               flags &= ~kTextAtLeastOne;
               continue;
            }
         } else {
            newchunk = NewChunk(layout, &maxChunks, start, 1, curX, 1000000000, baseline);
            if (newchunk) newchunk->fNumDisplayChars = -1;
            start++;
            goto wrapLine;
         }
      }
 
      // No more characters are going to go on this line, either because
      // no more characters can fit or there are no more characters left.
      // Consume all extra spaces at end of line.
 
      while ((start < end) && isspace(UChar_t(*start))) {
         if (!(flags & kTextIgnoreNewlines)) {
            if ((*start == '\n') || (*start == '\r')) {
               break;
            }
         }
         if (!(flags & kTextIgnoreTabs)) {
            if (*start == '\t') {
               break;
            }
         }
         start++;
      }
      if (chunk) {
         // Append all the extra spaces on this line to the end of the
         // last text chunk.
 
         charsThisChunk = start - (chunk->fStart + chunk->fNumChars);
         if (charsThisChunk > 0) {
            chunk->fNumChars += MeasureChars(chunk->fStart + chunk->fNumChars,
                                             charsThisChunk, 0, 0, &chunk->fTotalWidth);
            chunk->fTotalWidth += curX;
         }
      }
wrapLine:
      flags |= kTextAtLeastOne;
 
      // Save current line length, then move current position to start of
      // next line.
 
      if (curX > maxWidth) {
         maxWidth = curX;
      }
 
      // Remember width of this line, so that all chunks on this line
      // can be centered or right justified, if necessary.
 
      if (curLine >= maxLines) {
         int *newLengths;
 
         newLengths = new int[2 * maxLines];
         memcpy((void *) newLengths, lineLengths, maxLines * sizeof (int));
 
         if (lineLengths != staticLineLengths) {
            delete[] lineLengths;
         }
         lineLengths = newLengths;
         maxLines *= 2;
      }
      lineLengths[curLine] = curX;
      curLine++;
 
      curX = 0;
      baseline += h;
   }
 
   // If last line ends with a newline, then we need to make a 0 width
   // chunk on the next line. Otherwise "Hello" and "Hello\n" are the
   // same height.
 
   if ((layout->fNumChunks > 0) && ((flags & kTextIgnoreNewlines) == 0)) {
      if (layout->fChunks[layout->fNumChunks - 1].fStart[0] == '\n') {
         chunk = NewChunk(layout, &maxChunks, start, 0, curX, 1000000000, baseline);
         chunk->fNumDisplayChars = -1;
         baseline += h;
      }
   }
 
   // Using maximum line length, shift all the chunks so that the lines are
   // all justified correctly.
 
   curLine = 0;
   chunk = layout->fChunks;
   if (chunk) {
      y = chunk->fY;
      for (n = 0; n < layout->fNumChunks; n++) {
         int extra = maxWidth;
 
         if (chunk->fY != y) {
            curLine++;
            y = chunk->fY;
         }
         if (curLine < maxLines)
            extra = maxWidth - lineLengths[curLine];
         if (justify == kTextCenterX) {
            chunk->fX += extra / 2;
         } else if (justify == kTextRight) {
            chunk->fX += extra;
         }
         ++chunk;
      }
   }
 
   layout->fWidth = maxWidth;
   layoutHeight = baseline - fFM.fAscent;
   if (layout->fNumChunks == 0) {
      layoutHeight = h;
 
      // This fake chunk is used by the other procedures so that they can
      // pretend that there is a chunk with no chars in it, which makes
      // the coding simpler.
 
      layout->fNumChunks = 1;
      layout->fChunks = new LayoutChunk_t[1];
      layout->fChunks[0].fStart = string;
      layout->fChunks[0].fNumChars = 0;
      layout->fChunks[0].fNumDisplayChars = -1;
      layout->fChunks[0].fX = 0;
      layout->fChunks[0].fY = fFM.fAscent;
      layout->fChunks[0].fTotalWidth = 0;
      layout->fChunks[0].fDisplayWidth = 0;
   }
   if (width) {
      *width = layout->fWidth;
   }
   if (height) {
      *height = layoutHeight;
   }
   if (lineLengths != staticLineLengths) {
      delete[] lineLengths;
   }
 
   return layout;
}
 
////////////////////////////////////////////////////////////////////////////////
/// destructor
 
TGTextLayout::~TGTextLayout()
{
   if (fChunks) {
      delete[] fChunks;
   }
}
 
////////////////////////////////////////////////////////////////////////////////
/// Use the information in the TGTextLayout object to display a multi-line,
/// justified string of text.
///
/// This procedure is useful for simple widgets that need to display
/// single-font, multi-line text and want TGFont to handle the details.
///
/// dst       -- Window or pixmap in which to draw.
/// gc        -- Graphics context to use for drawing text.
/// x, y      -- Upper-left hand corner of rectangle in which to draw
///              (pixels).
/// firstChar -- The index of the first character to draw from the given
///              text item. 0 specfies the beginning.
/// lastChar  -- The index just after the last character to draw from the
///              given text item. A number < 0 means to draw all characters.
 
void TGTextLayout::DrawText(Drawable_t dst, GContext_t gc,
                            Int_t x, Int_t y, Int_t firstChar, Int_t lastChar) const
{
   Int_t i, numDisplayChars, drawX;
   LayoutChunk_t *chunk;
 
   if (lastChar < 0) lastChar = 100000000;
   chunk = fChunks;
 
   for (i = 0; i < fNumChunks; i++) {
      numDisplayChars = chunk->fNumDisplayChars;
      if ((numDisplayChars > 0) && (firstChar < numDisplayChars)) {
         if (firstChar <= 0) {
            drawX = 0;
            firstChar = 0;
         } else {
            fFont->MeasureChars(chunk->fStart, firstChar, 0, 0, &drawX);
         }
         if (lastChar < numDisplayChars) numDisplayChars = lastChar;
         fFont->DrawChars(dst, gc, chunk->fStart + firstChar, numDisplayChars - firstChar,
                           x + chunk->fX + drawX, y + chunk->fY);
      }
      firstChar -= chunk->fNumChars;
      lastChar -= chunk->fNumChars;
 
      if (lastChar <= 0) break;
      chunk++;
   }
}
 
////////////////////////////////////////////////////////////////////////////////
/// Use the information in the TGTextLayout object to display an underline
/// below an individual character. This procedure does not draw the text,
/// just the underline.
///
/// This procedure is useful for simple widgets that need to display
/// single-font, multi-line text with an individual character underlined
/// and want TGFont to handle the details. To display larger amounts of
/// underlined text, construct and use an underlined font.
///
/// dst       -- Window or pixmap in which to draw.
/// gc        -- Graphics context to use for drawing text.
/// x, y      -- Upper-left hand corner of rectangle in which to draw
///              (pixels).
/// underline -- Index of the single character to underline, or -1 for
///              no underline.
 
void TGTextLayout::UnderlineChar(Drawable_t dst, GContext_t gc,
                                Int_t x, Int_t y, Int_t underline) const
{
   int xx, yy, width, height;
 
   if ((CharBbox(underline, &xx, &yy, &width, &height) != 0)
      && (width != 0)) {
      gVirtualX->FillRectangle(dst, gc, x + xx,
                               y + yy + fFont->fFM.fAscent + fFont->fUnderlinePos,
                               (UInt_t) width, (UInt_t) fFont->fUnderlineHeight);
   }
}
 
////////////////////////////////////////////////////////////////////////////////
/// Use the information in the TGTextLayout token to determine the character
/// closest to the given point. The point must be specified with respect to
/// the upper-left hand corner of the text layout, which is considered to be
/// located at (0, 0).
///
/// Any point whose y-value is less that 0 will be considered closest to the
/// first character in the text layout; any point whose y-value is greater
/// than the height of the text layout will be considered closest to the last
/// character in the text layout.
///
/// Any point whose x-value is less than 0 will be considered closest to the
/// first character on that line; any point whose x-value is greater than the
/// width of the text layout will be considered closest to the last character
/// on that line.
///
/// The return value is the index of the character that was closest to the
/// point. Given a text layout with no characters, the value 0 will always
/// be returned, referring to a hypothetical zero-width placeholder character.
 
Int_t TGTextLayout::PointToChar(Int_t x, Int_t y) const
{
   LayoutChunk_t *chunk, *last;
   Int_t i, n, dummy, baseline, pos;
 
   if (y < 0) {
      // Point lies above any line in this layout. Return the index of
      // the first char.
 
      return 0;
   }
 
   // Find which line contains the point.
 
   last = chunk = fChunks;
   for (i = 0; i < fNumChunks; i++) {
      baseline = chunk->fY;
      if (y < baseline + fFont->fFM.fDescent) {
         if (x < chunk->fX) {
            // Point is to the left of all chunks on this line. Return
            // the index of the first character on this line.
 
            return (chunk->fStart - fString);
         }
         if (x >= fWidth) {
 
         // If point lies off right side of the text layout, return
         // the last char in the last chunk on this line. Without
         // this, it might return the index of the first char that
         // was located outside of the text layout.
 
            x = INT_MAX;
         }
 
         // Examine all chunks on this line to see which one contains
         // the specified point.
 
         last = chunk;
         while ((i < fNumChunks) && (chunk->fY == baseline)) {
            if (x < chunk->fX + chunk->fTotalWidth) {
 
               // Point falls on one of the characters in this chunk.
 
               if (chunk->fNumDisplayChars < 0) {
 
                  // This is a special chunk that encapsulates a single
                  // tab or newline char.
 
                  return (chunk->fStart - fString);
               }
               n = fFont->MeasureChars(chunk->fStart, chunk->fNumChars,
                                       x + 1 - chunk->fX, kTextPartialOK, &dummy);
               return ((chunk->fStart + n - 1) - fString);
            }
            last = chunk;
            chunk++;
            i++;
         }
 
         // Point is to the right of all chars in all the chunks on this
         // line. Return the index just past the last char in the last
         // chunk on this line.
 
         pos = (last->fStart + last->fNumChars) - fString;
         if (i < fNumChunks) pos--;
         return pos;
      }
      last = chunk;
      chunk++;
   }
 
   // Point lies below any line in this text layout. Return the index
   // just past the last char.
 
   return ((last->fStart + last->fNumChars) - fString);
}
 
////////////////////////////////////////////////////////////////////////////////
/// Use the information in the TGTextLayout token to return the bounding box
/// for the character specified by index.
///
/// The width of the bounding box is the advance width of the character, and
/// does not include and left- or right-bearing. Any character that extends
/// partially outside of the text layout is considered to be truncated at the
/// edge. Any character which is located completely outside of the text
/// layout is considered to be zero-width and pegged against the edge.
///
/// The height of the bounding box is the line height for this font,
/// extending from the top of the ascent to the bottom of the descent.
/// Information about the actual height of the individual letter is not
/// available.
///
/// A text layout that contains no characters is considered to contain a
/// single zero-width placeholder character.
///
/// The return value is 0 if the index did not specify a character in the
/// text layout, or non-zero otherwise. In that case, *bbox is filled with
/// the bounding box of the character.
///
/// layout -- Layout information, from a previous call to ComputeTextLayout().
/// index  -- The index of the character whose bbox is desired.
/// x, y   -- Filled with the upper-left hand corner, in pixels, of the
///           bounding box for the character specified by index, if non-NULL.
/// w, h   -- Filled with the width and height of the bounding box for the
///           character specified by index, if non-NULL.
 
Int_t TGTextLayout::CharBbox(Int_t index, Int_t *x, Int_t *y, Int_t *w, Int_t *h) const
{
   LayoutChunk_t *chunk;
   Int_t i, xx = 0, ww = 0;
 
   if (index < 0) {
      return 0;
   }
 
   chunk = fChunks;
 
   for (i = 0; i < fNumChunks; i++) {
      if (chunk->fNumDisplayChars < 0) {
         if (!index) {
            xx = chunk->fX;
            ww = chunk->fTotalWidth;
            goto check;
         }
      } else if (index < chunk->fNumChars) {
         if (x) {
            fFont->MeasureChars(chunk->fStart, index, 0, 0, &xx);
            xx += chunk->fX;
         }
         if (w) {
            fFont->MeasureChars(chunk->fStart + index, 1, 0, 0, &ww);
         }
         goto check;
      }
      index -= chunk->fNumChars;
      chunk++;
   }
   if (!index) {
 
      // Special case to get location just past last char in layout.
 
      chunk--;
      xx = chunk->fX + chunk->fTotalWidth;
      ww = 0;
   } else {
      return 0;
   }
 
   // Ensure that the bbox lies within the text layout. This forces all
   // chars that extend off the right edge of the text layout to have
   // truncated widths, and all chars that are completely off the right
   // edge of the text layout to peg to the edge and have 0 width.
 
check:
   if (y) {
      *y = chunk->fY - fFont->fFM.fAscent;
   }
   if (h) {
      *h = fFont->fFM.fAscent + fFont->fFM.fDescent;
   }
   if (xx > fWidth) {
      xx = fWidth;
   }
   if (x) {
      *x = xx;
   }
   if (w) {
      if (xx + ww > fWidth) {
         ww = fWidth - xx;
      }
      *w = ww;
   }
   return 1;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Computes the distance in pixels from the given point to the given
/// text layout. Non-displaying space characters that occur at the end of
/// individual lines in the text layout are ignored for hit detection
/// purposes.
///
/// The return value is 0 if the point (x, y) is inside the text layout.
/// If the point isn't inside the text layout then the return value is the
/// distance in pixels from the point to the text item.
///
/// x, y -- Coordinates of point to check, with respect to the upper-left
///         corner of the text layout (in pixels).
 
Int_t TGTextLayout::DistanceToText(Int_t x, Int_t y) const
{
   Int_t i, x1, x2, y1, y2, xDiff, yDiff, dist, minDist, ascent, descent;
   LayoutChunk_t *chunk;
 
   ascent = fFont->fFM.fAscent;
   descent = fFont->fFM.fDescent;
 
   minDist = 0;
   chunk = fChunks;
   for (i = 0; i < fNumChunks; i++) {
      if (chunk->fStart[0] == '\n') {
 
         // Newline characters are not counted when computing distance
         // (but tab characters would still be considered).
 
         chunk++;
         continue;
      }
      x1 = chunk->fX;
      y1 = chunk->fY - ascent;
      x2 = chunk->fX + chunk->fDisplayWidth;
      y2 = chunk->fY + descent;
 
      if (x < x1) {
         xDiff = x1 - x;
      } else if (x >= x2) {
         xDiff = x - x2 + 1;
      } else {
         xDiff = 0;
      }
 
      if (y < y1) {
         yDiff = y1 - y;
      } else if (y >= y2) {
         yDiff = y - y2 + 1;
      } else {
         yDiff = 0;
      }
      if ((xDiff == 0) && (yDiff == 0)) {
         return 0;
      }
      dist = (int) TMath::Hypot((Double_t) xDiff, (Double_t) yDiff);
      if ((dist < minDist) || !minDist) {
         minDist = dist;
      }
      chunk++;
   }
   return minDist;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Determines whether a text layout lies entirely inside, entirely outside,
/// or overlaps a given rectangle. Non-displaying space characters that occur
/// at the end of individual lines in the text layout are ignored for
/// intersection calculations.
///
/// The return value is -1 if the text layout is entirely outside of the
/// rectangle, 0 if it overlaps, and 1 if it is entirely inside of the
/// rectangle.
///
/// x, y -- Upper-left hand corner, in pixels, of rectangular area to compare
///         with text layout. Coordinates are with respect to the upper-left
///         hand corner of the text layout itself.
/// w, h -- The width and height of the above rectangular area, in pixels.
 
Int_t TGTextLayout::IntersectText(Int_t x, Int_t y, Int_t w, Int_t h) const
{
   Int_t result, i, x1, y1, x2, y2;
   LayoutChunk_t *chunk;
   Int_t left, top, right, bottom;
 
   // Scan the chunks one at a time, seeing whether each is entirely in,
   // entirely out, or overlapping the rectangle.  If an overlap is
   // detected, return immediately; otherwise wait until all chunks have
   // been processed and see if they were all inside or all outside.
 
   chunk = fChunks;
 
   left = x;
   top = y;
   right = x + w;
   bottom = y + h;
 
   result = 0;
   for (i = 0; i < fNumChunks; i++) {
      if (chunk->fStart[0] == '\n') {
 
         // Newline characters are not counted when computing area
         // intersection (but tab characters would still be considered).
 
         chunk++;
         continue;
      }
      x1 = chunk->fX;
      y1 = chunk->fY - fFont->fFM.fAscent;
      x2 = chunk->fX + chunk->fDisplayWidth;
      y2 = chunk->fY + fFont->fFM.fDescent;
 
      if ((right < x1) || (left >= x2) || (bottom < y1) || (top >= y2)) {
         if (result == 1) {
            return 0;
         }
         result = -1;
      } else if ((x1 < left) || (x2 >= right) || (y1 < top) || (y2 >= bottom)) {
         return 0;
      } else if (result == -1) {
         return 0;
      } else {
         result = 1;
      }
      chunk++;
   }
   return result;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Outputs the contents of a text layout in Postscript format. The set of
/// lines in the text layout will be rendered by the user supplied Postscript
/// function. The function should be of the form:
///
///     justify x y string  function  --
///
/// Justify is -1, 0, or 1, depending on whether the following string should
/// be left, center, or right justified, x and y is the location for the
/// origin of the string, string is the sequence of characters to be printed,
/// and function is the name of the caller-provided function; the function
/// should leave nothing on the stack.
///
/// The meaning of the origin of the string (x and y) depends on the
/// justification. For left justification, x is where the left edge of the
/// string should appear. For center justification, x is where the center of
/// the string should appear. And for right justification, x is where the
/// right edge of the string should appear. This behavior is necessary
/// because, for example, right justified text on the screen is justified
/// with screen metrics. The same string needs to be justified with printer
/// metrics on the printer to appear in the correct place with respect to
/// other similarly justified strings. In all circumstances, y is the
/// location of the baseline for the string.
///
/// result is modified to hold the Postscript code that will render the text
/// layout.
 
void TGTextLayout::ToPostscript(TString *result) const
{
#define MAXUSE 128
   char buf[MAXUSE + 10];
   LayoutChunk_t *chunk;
   Int_t i, j, used, c, baseline;
 
   chunk = fChunks;
   baseline = chunk->fY;
   used = 0;
   buf[used++] = '(';
 
   for (i = 0; i < fNumChunks; i++) {
      if (baseline != chunk->fY) {
         buf[used++] = ')';
         buf[used++] = '\n';
         buf[used++] = '(';
         baseline = chunk->fY;
      }
      if (chunk->fNumDisplayChars <= 0) {
         if (chunk->fStart[0] == '\t') {
            buf[used++] = '\\';
            buf[used++] = 't';
         }
      } else {
         for (j = 0; j < chunk->fNumDisplayChars; j++) {
            c = UChar_t(chunk->fStart[j]);
            if ((c == '(') || (c == ')') || (c == '\\') || (c < 0x20) || (c >= UChar_t(0x7f))) {
 
            // Tricky point: the "03" is necessary in the sprintf
            // below, so that a full three digits of octal are
            // always generated. Without the "03", a number
            // following this sequence could be interpreted by
            // Postscript as part of this sequence.
 
               // coverity[secure_coding]
               snprintf(buf + used, MAXUSE + 10 - used, "\\%03o", c);
               used += 4;
            } else {
               buf[used++] = c;
            }
            if (used >= MAXUSE) {
               buf[used] = '\0';
               result->Append(buf);
               used = 0;
            }
         }
      }
      if (used >= MAXUSE) {
         // If there are a whole bunch of returns or tabs in a row,
         // then buf[] could get filled up.
 
         buf[used] = '\0';
         result->Append(buf);
         used = 0;
      }
      chunk++;
   }
   buf[used++] = ')';
   buf[used++] = '\n';
   buf[used]   = '\0';
 
   result->Append(buf);
}
 
////////////////////////////////////////////////////////////////////////////////
/// Helper function for ComputeTextLayout(). Encapsulates a measured set of
/// characters in a chunk that can be quickly drawn.
///
/// Returns a pointer to the new chunk in the text layout. The text layout is
/// reallocated to hold more chunks as necessary.
///
/// Currently, ComputeTextLayout() stores contiguous ranges of "normal"
/// characters in a chunk, along with individual tab and newline chars in
/// their own chunks. All characters in the text layout are accounted for.
 
LayoutChunk_t *TGFont::NewChunk(TGTextLayout *layout, Int_t *maxPtr,
                                const char *start, Int_t numChars,
                                Int_t curX, Int_t newX, Int_t y) const
{
   LayoutChunk_t *chunk;
   Int_t i, maxChunks;
 
   maxChunks = *maxPtr;
   if (layout->fNumChunks == maxChunks) {
      if (maxChunks == 0) {
         maxChunks = 1;
      } else {
         maxChunks *= 2;
      }
      chunk = new LayoutChunk_t[maxChunks];
 
      if (layout->fNumChunks > 0) {
         for (i=0; i<layout->fNumChunks; ++i) chunk[i] = layout->fChunks[i];
         delete[] layout->fChunks;
      }
      layout->fChunks = chunk;
      *maxPtr = maxChunks;
   }
 
   chunk = &layout->fChunks[layout->fNumChunks];
   chunk->fStart = start;
   chunk->fNumChars = numChars;
   chunk->fNumDisplayChars = numChars;
   chunk->fX = curX;
   chunk->fY = y;
   chunk->fTotalWidth = newX - curX;
   chunk->fDisplayWidth = newX - curX;
   layout->fNumChunks++;
 
   return chunk;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Draw a string of characters on the screen. DrawCharsExp() expands
/// control characters that occur in the string to \\X or \\xXX sequences.
/// DrawChars() just draws the strings.
///
/// dst      -- Window or pixmap in which to draw.
/// gc       -- Graphics context for drawing characters.
/// source   -- Characters to be displayed. Need not be'\0' terminated.
///             For DrawChars(), all meta-characters (tabs, control
///             characters, and newlines) should be stripped out of the
///             string that is passed to this function. If they are not
///             stripped out, they will be displayed as regular printing
///             characters.
/// numChars -- Number of characters in string.
/// x, y     -- Coordinates at which to place origin of string when drawing.
 
void TGFont::DrawCharsExp(Drawable_t dst, GContext_t gc,
                          const char *source, Int_t numChars,
                          Int_t x, Int_t y) const
{
   const char *p;
   Int_t i, type;
   char buf[4];
 
   p = source;
   for (i = 0; i < numChars; i++) {
      type = fTypes[UChar_t(*p)];
      if (type != kCharNormal) {
         DrawChars(dst, gc, source, p - source, x, y);
         x += gVirtualX->TextWidth(fFontStruct, source, p - source);
         if (type == kCharReplace) {
            DrawChars(dst, gc, buf, GetControlCharSubst(UChar_t(*p), buf), x, y);
            x += fWidths[UChar_t(*p)];
         }
         source = p + 1;
      }
      p++;
   }
 
   DrawChars(dst, gc, source, p - source, x, y);
}
 
////////////////////////////////////////////////////////////////////////////////
/// Perform a quick sanity check to ensure we won't overflow the X
/// coordinate space.
 
void TGFont::DrawChars(Drawable_t dst, GContext_t gc,
                       const char *source, Int_t numChars,
                       Int_t x, Int_t y) const
{
   Int_t max_width =  gVirtualX->TextWidth(fFontStruct, "@", 1);
 
   if ((x + (max_width * numChars) > 0x7fff)) {
      int length;
 
      // The string we are being asked to draw is too big and would overflow
      // the X coordinate space. Unfortunately X servers aren't too bright
      // and so they won't deal with this case cleanly. We need to truncate
      // the string before sending it to X.
 
      numChars = MeasureChars(source, numChars, 0x7fff - x, 0, &length);
   }
 
   gVirtualX->DrawString(dst, gc, x, y, source, numChars);
 
   if (fFA.fUnderline != 0) {
      gVirtualX->FillRectangle(dst, gc, x,  y + fUnderlinePos,
                          (UInt_t) gVirtualX->TextWidth(fFontStruct, source, numChars),
                          (UInt_t) fBarHeight);
   }
   if (fFA.fOverstrike != 0) {
      y -= fFM.fDescent + fFM.fAscent / 10;
      gVirtualX->FillRectangle(dst, gc, x, y,
                          (UInt_t) gVirtualX->TextWidth(fFontStruct, source, numChars),
                          (UInt_t) fBarHeight);
   }
}
 
////////////////////////////////////////////////////////////////////////////////
/// Create a font pool.
 
TGFontPool::TGFontPool(TGClient *client)
{
   fClient = client;
   fList   = new THashTable(50);
   fList->SetOwner();
 
   fNamedTable = new THashTable(50);
   fNamedTable->SetOwner();
 
   fUidTable = new THashTable(50);
   fUidTable->SetOwner();
}
 
////////////////////////////////////////////////////////////////////////////////
/// Cleanup font pool.
 
TGFontPool::~TGFontPool()
{
   delete fList;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Get the specified font.
/// The font can be one of the following forms:
///        XLFD (see X documentation)
///        "Family [size [style] [style ...]]"
/// Returns 0 if error or no font can be found.
/// If fixedDefault is false the "fixed" font will not be substituted
/// as fallback when the asked for font does not exist.
 
TGFont *TGFontPool::GetFont(const char *font, Bool_t fixedDefault)
{
   if (!font || !*font) {
      Error("GetFont", "argument may not be 0 or empty");
      return 0;
   }
 
   TGFont *f = (TGFont*)fList->FindObject(font);
 
   if (f) {
      f->AddReference();
      return f;
   }
 
   TNamedFont *nf = (TNamedFont*)fNamedTable->FindObject(font);
 
   if (nf) {
      // Construct a font based on a named font.
      nf->AddReference();
      f = GetFontFromAttributes(&nf->fFA, 0);
 
   } else {
 
      // Native font (aka string in XLFD format)?
      Int_t errsav = gErrorIgnoreLevel;
      gErrorIgnoreLevel = kFatal;
 
      f = GetNativeFont(font, fixedDefault);
      gErrorIgnoreLevel = errsav;
 
      if (!f) {
         FontAttributes_t fa;
 
         if (!ParseFontName(font, &fa)) {
            //fontCache.DeleteHashEntry(cacheHash);
 
            return 0;
         }
 
         // String contained the attributes inline.
         f = GetFontFromAttributes(&fa, 0);
      }
   }
 
   if (!f) return 0;
 
   fList->Add(f);
 
   f->SetRefCount(1);
   //f->cacheHash = cacheHash;
   f->fNamedHash = nf;
 
   f->MeasureChars("0", 1, 0, 0, &f->fTabWidth);
 
   if (!f->fTabWidth) {
      f->fTabWidth = f->fFM.fMaxWidth;
   }
   f->fTabWidth *= 8;
 
   // Make sure the tab width isn't zero (some fonts may not have enough
   // information to set a reasonable tab width).
 
   if (!f->fTabWidth) {
      f->fTabWidth = 1;
   }
 
   // Get information used for drawing underlines in generic code on a
   // non-underlined font.
 
   Int_t descent = f->fFM.fDescent;
   f->fUnderlinePos = descent/2;  // ==!== could be set by MakeFont()
   f->fUnderlineHeight = f->fFA.fPointsize/10;
 
   if (!f->fUnderlineHeight) {
      f->fUnderlineHeight = 1;
   }
   if (f->fUnderlinePos + f->fUnderlineHeight > descent) {
 
      // If this set of values would cause the bottom of the underline
      // bar to stick below the descent of the font, jack the underline
      // up a bit higher.
 
      f->fUnderlineHeight = descent - f->fUnderlinePos;
 
      if (!f->fUnderlineHeight) {
         f->fUnderlinePos--;
         f->fUnderlineHeight = 1;
      }
   }
 
   return f;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Use font, i.e. increases ref count of specified font. Returns 0
/// if font is not found.
 
TGFont *TGFontPool::GetFont(const TGFont *font)
{
   TGFont *f = (TGFont*)fList->FindObject(font);
 
   if (f) {
      f->AddReference();
      return f;
   }
 
   return 0;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Use font, i.e. increases ref count of specified font.
 
TGFont *TGFontPool::GetFont(FontStruct_t fs)
{
   TGFont *f = FindFont(fs);
 
   if (f) {
      f->AddReference();
      return f;
   }
 
   static int i = 0;
   f = MakeFont(0, fs, TString::Format("unknown-%d", i));
   fList->Add(f);
   i++;
 
   return f;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Returns font specified bay family, pixel/point size, weight and slant
///  negative value of ptsize means size in pixels
///  positive value of ptsize means size in points
///
///  For example:
///    TGFont *font = fpool->GetFont("helvetica", -9, kFontWeightNormal, kFontSlantRoman);
///    font->Print();
 
TGFont *TGFontPool::GetFont(const char *family, Int_t ptsize, Int_t weight, Int_t slant)
{
   const char *s;
   TString tmp;
 
   tmp = TString::Format("%s %d", family, ptsize);
   s = FindStateString(gWeightMap, weight);
   if (s) {
      tmp += " ";
      tmp + s;
   }
   s = FindStateString(gSlantMap, slant);
   if (s) {
      tmp += " ";
      tmp += s;
   }
   return GetFont(tmp.Data());
}
 
////////////////////////////////////////////////////////////////////////////////
/// Free font. If ref count is 0 delete font.
 
void TGFontPool::FreeFont(const TGFont *font)
{
   TGFont *f = (TGFont*) fList->FindObject(font);
   if (f) {
      if (f->RemoveReference() == 0) {
         if (font->fNamedHash) {
 
            // The font is being deleted. Determine if the associated named
            // font definition should and/or can be deleted too.
 
            TNamedFont *nf = (TNamedFont *) font->fNamedHash;
 
            if ((nf->RemoveReference() == 0) && (nf->fDeletePending != 0)) {
               fNamedTable->Remove(nf);
               delete nf;
            }
         }
         fList->Remove(f);
         delete font;
      }
   }
}
 
////////////////////////////////////////////////////////////////////////////////
/// Find font based on its font struct. Returns 0 if font is not found.
 
TGFont *TGFontPool::FindFont(FontStruct_t font) const
{
   TIter next(fList);
   TGFont *f = 0;
 
   while ((f = (TGFont*) next())) {
      if (f->fFontStruct == font) {
         return f;
      }
   }
 
   return 0;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Find font based on its font handle. Returns 0 if font is not found.
 
TGFont *TGFontPool::FindFontByHandle(FontH_t font) const
{
   TIter next(fList);
   TGFont *f = 0;
 
   while ((f = (TGFont*) next())) {
      if (f->fFontH == font) {
         return f;
      }
   }
 
   return 0;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Given a string, this procedure returns a unique identifier for the string.
///
/// This procedure returns a pointer to a new char string corresponding to
/// the "string" argument. The new string has a value identical to string
/// (strcmp will return 0), but it's guaranteed that any other calls to this
/// procedure with a string equal to "string" will return exactly the same
/// result (i.e. can compare pointer *values* directly, without having to
/// call strcmp on what they point to).
 
const char *TGFontPool::GetUid(const char *string)
{
   TObjString *obj = 0;
   obj = (TObjString*)fUidTable->FindObject(string);
 
   if (!obj) {
      obj = new TObjString(string);
      fUidTable->Add(obj);
   }
 
   return (const char *)obj->GetName();
}
 
////////////////////////////////////////////////////////////////////////////////
/// Return information about the font attributes as an array of strings.
///
/// An array of FONT_NUMFIELDS strings is returned holding the value of the
/// font attributes in the following order:
/// family size weight slant underline overstrike
 
char **TGFontPool::GetAttributeInfo(const FontAttributes_t *fa)
{
   Int_t i, num;
   const char *str = 0;
 
   char **result = new char*[FONT_NUMFIELDS];
 
   for (i = 0; i < FONT_NUMFIELDS; ++i) {
      str = 0;
      num = 0;
 
      switch (i) {
      case FONT_FAMILY:
         str = fa->fFamily;
         if (!str) str = "";
         break;
 
      case FONT_SIZE:
         num = fa->fPointsize;
         break;
 
      case FONT_WEIGHT:
         str = FindStateString(gWeightMap, fa->fWeight);
         break;
 
      case FONT_SLANT:
         str = FindStateString(gSlantMap, fa->fSlant);
         break;
 
      case FONT_UNDERLINE:
         num = fa->fUnderline;
         break;
 
      case FONT_OVERSTRIKE:
         num = fa->fOverstrike;
         break;
      }
 
      if (str) {
         int len = strlen(str)+1;
         result[i] = new char[len];
         strlcpy(result[i], str, len);
      } else {
         result[i] = new char[20];
         snprintf(result[i], 20, "%d", num);
      }
   }
 
   return result;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Free attributes info.
 
void TGFontPool::FreeAttributeInfo(char **info)
{
   Int_t i;
 
   if (info) {
      for (i = 0; i < FONT_NUMFIELDS; ++i) {
         if (info[i]) {
            delete[] info[i];
         }
      }
      delete[] info;
   }
}
 
////////////////////////////////////////////////////////////////////////////////
/// List all fonts in the pool.
 
void TGFontPool::Print(Option_t *opt) const
{
   fList->Print(opt);
}
 
////////////////////////////////////////////////////////////////////////////////
/// Save the used font as a C++ statement(s) on output stream out.
 
void TGFont::SavePrimitive(std::ostream &out, Option_t * /*= ""*/)
{
   out << "   \n";
 
   //  declare a font object to reflect required user changes
   if (!gROOT->ClassSaved(TGFont::Class()))
      out << "   TGFont *ufont;         // will reflect user font changes\n";
   out << "   ufont = gClient->GetFont(\"" << TString(GetName()).ReplaceSpecialCppChars() << "\");\n";
}
 
////////////////////////////////////////////////////////////////////////////////
 
static char *GetToken(char *str)
{
   static char *p = 0;
   char *retp;
 
   if (str) p = str;
 
   if (!p) {
      return 0;
   }
   if (!*p) {
      return 0;
   }
 
   while (*p && ((*p == ' ') || (*p == '\t'))) {   // skip spaces
      ++p;
   }
 
   if (!*p) {
      return 0;
   }
 
   if (*p == '"') {  // quoted string
      retp = ++p;
 
      if (!*p) {
         return 0;
      }
 
      while (*p && (*p != '"')) {
         ++p;
      }
 
      if (*p == '"') {
         *p++ = '\0';
      }
   } else {
      retp = p;
      while (*p && (*p != ' ') && (*p != '\t')) {
         ++p;
      }
      if (*p) {
         *p++ = '\0';
      }
   }
 
   return retp;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Converts a string into a set of font attributes that can be used to
/// construct a font.
///
/// The string can be one of the following forms:
///        XLFD (see X documentation)
///        "Family [size [style] [style ...]]"
///
/// The return value is kFALSE if the object was syntactically
/// invalid. Otherwise, fills the font attribute buffer with the values
/// parsed from the string and returns kTRUE. The structure must already be
/// properly initialized.
 
Bool_t TGFontPool::ParseFontName(const char *string, FontAttributes_t *fa)
{
   char *s;
   int n, result;
 
   XLFDAttributes_t xa;
 
   int len = strlen(string)+1;
   char *str = new char[len];
   strlcpy(str, string, len);
 
   if (*str == '-' || *str == '*') {
 
    // This appears to be an XLFD.
 
      xa.fFA = *fa;
      result = ParseXLFD(str, &xa);
      if (result) {
         *fa = xa.fFA;
         delete[] str;
         return kTRUE;  //OK
      }
   }
 
   // Wasn't an XLFD or "-option value" string. Try it as a
   // "font size style" list.
 
   s = GetToken(str);
   if (!s) {
      delete[] str;
      return kFALSE;
   }
   fa->fFamily = GetUid(s);
 
   s = GetToken(0);
 
   if (s) {
      char *end;
 
      fa->fPointsize = strtol(s, &end, 0);
      if ((errno == ERANGE) || (end == s)) {
         delete[] str;
         return kFALSE;
      }
   }
 
   while ((s = GetToken(0))) {
      n = FindStateNum(gWeightMap, s);
      if ((EFontWeight)n != kFontWeightUnknown) {
         fa->fWeight = n;
         continue;
      }
      n = FindStateNum(gSlantMap, s);
      // tell coverity that n is an integer value, and not an enum, even if
      // we compare it with an enum value (which is -1 in both case anyway)
      // coverity[mixed_enums]
      if ((EFontSlant)n != kFontSlantUnknown) {
         fa->fSlant = n;
         continue;
      }
      n = FindStateNum(gUnderlineMap, s);
      if (n) {
         fa->fUnderline = n;
         continue;
      }
      n = FindStateNum(gOverstrikeMap, s);
      if (n) {
         fa->fOverstrike = n;
         continue;
      }
 
      // Unknown style.
 
      delete[] str;
      return kFALSE;
   }
 
   delete[] str;
   return kTRUE;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Break up a fully specified XLFD into a set of font attributes.
///
/// Return value is kFALSE if string was not a fully specified XLFD.
/// Otherwise, fills font attribute buffer with the values parsed from
/// the XLFD and returns kTRUE.
///
/// string -- Parseable font description string.
/// xa     -- XLFD attributes structure whose fields are to be modified.
///           Structure must already be properly initialized.
 
Bool_t TGFontPool::ParseXLFD(const char *string, XLFDAttributes_t *xa)
{
   char *src;
   const char *str;
   int i, j;
   char *field[XLFD_NUMFIELDS + 2];
   TString ds("");
 
   memset(field, '\0', sizeof (field));
 
   str = string;
   if (*str == '-') str++;
 
   ds.Append((char *) str);
   src = (char*)ds.Data();
 
   field[0] = src;
   for (i = 0; *src != '\0'; src++) {
      if (isupper(UChar_t(*src))) {
         *src = tolower(UChar_t(*src));
      }
      if (*src == '-') {
         i++;
         if (i > XLFD_NUMFIELDS) {
           break;
         }
         *src = '\0';
         field[i] = src + 1;
      }
   }
 
   // An XLFD of the form -adobe-times-medium-r-*-12-*-* is pretty common,
   // but it is (strictly) malformed, because the first * is eliding both
   // the Setwidth and the Addstyle fields. If the Addstyle field is a
   // number, then assume the above incorrect form was used and shift all
   // the rest of the fields up by one, so the number gets interpreted
   // as a pixelsize.
 
   if ((i > XLFD_ADD_STYLE) && (FieldSpecified(field[XLFD_ADD_STYLE]))) {
      if (atoi(field[XLFD_ADD_STYLE]) != 0) {
         for (j = XLFD_NUMFIELDS - 1; j >= XLFD_ADD_STYLE; j--) {
            field[j + 1] = field[j];
         }
         field[XLFD_ADD_STYLE] = 0;
         i++;
      }
   }
 
   // Bail if we don't have enough of the fields (up to pointsize).
 
   if (i < XLFD_FAMILY) {
      return kFALSE;
   }
   if (FieldSpecified(field[XLFD_FOUNDRY])) {
      xa->fFoundry = GetUid(field[XLFD_FOUNDRY]);
   }
   if (FieldSpecified(field[XLFD_FAMILY])) {
      xa->fFA.fFamily = GetUid(field[XLFD_FAMILY]);
   }
   if (FieldSpecified(field[XLFD_WEIGHT])) {
      xa->fFA.fWeight = FindStateNum(gXlfdgWeightMap, field[XLFD_WEIGHT]);
   }
   if (FieldSpecified(field[XLFD_SLANT])) {
      xa->fSlant = FindStateNum(gXlfdSlantMap, field[XLFD_SLANT]);
      if (xa->fSlant == kFontSlantRoman) {
         xa->fFA.fSlant = kFontSlantRoman;
      } else {
         xa->fFA.fSlant = kFontSlantItalic;
      }
   }
   if (FieldSpecified(field[XLFD_SETWIDTH])) {
      xa->fSetwidth = FindStateNum(gXlfdSetwidthMap, field[XLFD_SETWIDTH]);
   }
   // XLFD_ADD_STYLE ignored.
 
   // Pointsize in tenths of a point, but treat it as tenths of a pixel.
 
   if (FieldSpecified(field[XLFD_POINT_SIZE])) {
      if (field[XLFD_POINT_SIZE][0] == '[') {
 
         // Some X fonts have the point size specified as follows:
         //
         //      [ N1 N2 N3 N4 ]
         //
         // where N1 is the point size (in points, not decipoints!), and
         // N2, N3, and N4 are some additional numbers that I don't know
         // the purpose of, so I ignore them.
 
         xa->fFA.fPointsize = atoi(field[XLFD_POINT_SIZE] + 1);
      } else {
         char *end;
 
         xa->fFA.fPointsize = strtol(field[XLFD_POINT_SIZE], &end, 0);
         if (errno == ERANGE || end == field[XLFD_POINT_SIZE]) {
            return kFALSE;
         }
         xa->fFA.fPointsize /= 10;
      }
   }
 
   // Pixel height of font. If specified, overrides pointsize.
 
   if (FieldSpecified(field[XLFD_PIXEL_SIZE])) {
      if (field[XLFD_PIXEL_SIZE][0] == '[') {
 
         // Some X fonts have the pixel size specified as follows:
         //
         //      [ N1 N2 N3 N4 ]
         //
         // where N1 is the pixel size, and where N2, N3, and N4
         // are some additional numbers that I don't know
         // the purpose of, so I ignore them.
 
         xa->fFA.fPointsize = atoi(field[XLFD_PIXEL_SIZE] + 1);
      } else {
         char *end;
 
         xa->fFA.fPointsize = strtol(field[XLFD_PIXEL_SIZE], &end, 0);
         if (errno == ERANGE || end == field[XLFD_PIXEL_SIZE]) {
            return kFALSE;
         }
      }
   }
   xa->fFA.fPointsize = -xa->fFA.fPointsize;
 
   // XLFD_RESOLUTION_X ignored.
 
   // XLFD_RESOLUTION_Y ignored.
 
   // XLFD_SPACING ignored.
 
   // XLFD_AVERAGE_WIDTH ignored.
 
   if (FieldSpecified(field[XLFD_REGISTRY])) {
      xa->fCharset = FindStateNum(gXlfdCharsetMap, field[XLFD_REGISTRY]);
   }
   if (FieldSpecified(field[XLFD_ENCODING])) {
      xa->fEncoding = atoi(field[XLFD_ENCODING]);
   }
 
   return kTRUE;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Given a lookup table, map a string to a number in the table.
///
/// If strKey was equal to the string keys of one of the elements in the
/// table, returns the numeric key of that element. Returns the numKey
/// associated with the last element (the NULL string one) in the table
/// if strKey was not equal to any of the string keys in the table.
 
Int_t TGFontPool::FindStateNum(const FontStateMap_t *map, const char *strKey)
{
   const FontStateMap_t *m;
 
   if (!map->fStrKey) {
      return 0;
   }
 
   for (m = map; m->fStrKey != 0; m++) {
      if (strcasecmp(strKey, m->fStrKey) == 0) {
         return m->fNumKey;
      }
   }
   return m->fNumKey;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Given a lookup table, map a number to a string in the table.
///
/// If numKey was equal to the numeric key of one of the elements in the
/// table, returns the string key of that element. Returns NULL if numKey
/// was not equal to any of the numeric keys in the table
 
const char *TGFontPool::FindStateString(const FontStateMap_t *map, Int_t numKey)
{
   for ( ; map->fStrKey != 0; map++) {
      if (numKey == map->fNumKey) return map->fStrKey;
   }
   return 0;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Helper function for ParseXLFD(). Determines if a field in the XLFD was
/// set to a non-null, non-don't-care value.
///
/// The return value is kFALSE if the field in the XLFD was not set and
/// should be ignored, kTRUE otherwise.
///
/// field -- The field of the XLFD to check. Strictly speaking, only when
///          the string is "*" does it mean don't-care. However, an
///          unspecified or question mark is also interpreted as don't-care.
 
Bool_t TGFontPool::FieldSpecified(const char *field)
{
   char ch;
 
   if (!field || !strlen(field)) {
      return kFALSE;
   }
   ch = field[0];
 
   return (ch != '*' && ch != '?');
}
 
////////////////////////////////////////////////////////////////////////////////
/// Given a font, return a textual string identifying it.
 
const char *TGFontPool::NameOfFont(TGFont *font)
{
   return font->GetName();
}
 
////////////////////////////////////////////////////////////////////////////////
/// Return information about the font families that are available on the
/// current display.
///
/// An array of strings is returned holding a list of all the available font
/// families. The array is terminated with a NULL pointer.
 
char **TGFontPool::GetFontFamilies()
{
   Int_t i, numNames;
   char *family, *end, *p;
 
   THashTable familyTable(100);
   familyTable.SetOwner();
 
   char **nameList;
   char **dst;
 
   // coverity[returned_null]
   // coverity[dereference]
   nameList = gVirtualX->ListFonts("*", 10000, numNames);
 
   for (i = 0; i < numNames; i++) {
      if (nameList[i][0] != '-') {
         continue;
      }
      family = strchr(nameList[i] + 1, '-');
      if (!family) {
         continue;
      }
      family++;
      end = strchr(family, '-');
      if (!end) {
         continue;
      }
      *end = '\0';
      for (p = family; *p != '\0'; p++) {
         if (isupper(UChar_t(*p))) {
            *p = tolower(UChar_t(*p));
         }
      }
      if (!familyTable.FindObject(family)) {
         familyTable.Add(new TObjString(family));
      }
   }
 
   UInt_t entries = familyTable.GetEntries();
   dst = new char*[entries+1];
 
   TIter next(&familyTable);
   i = 0;
   TObject *obj;
 
   while ((obj = next())) {
      dst[i] = StrDup(obj->GetName());
      i++;
   }
   dst[i] = 0;
 
   gVirtualX->FreeFontNames(nameList);
   return dst;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Delete an array of families allocated GetFontFamilies() method
 
void TGFontPool::FreeFontFamilies(char **f)
{
   Int_t i;
 
   if (!f) return;
 
   for (i = 0; f[i] != 0; ++i) {
      delete[] f[i];
   }
   delete[] f;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Given a desired set of attributes for a font, find a font with the
/// closest matching attributes and create a new TGFont object.
/// The return value is a pointer to a TGFont object that represents the
/// font with the desired attributes. If a font with the desired attributes
/// could not be constructed, some other font will be substituted
/// automatically.
///
/// Every call to this procedure returns a new TGFont object, even if the
/// specified attributes have already been seen before.
 
TGFont *TGFontPool::GetFontFromAttributes(FontAttributes_t *fa, TGFont *fontPtr)
{
   Int_t numNames, score, i, scaleable, pixelsize, xaPixelsize;
   Int_t bestIdx, bestScore, bestScaleableIdx, bestScaleableScore;
   XLFDAttributes_t xa;
   TString buf;
   char **nameList;
   TGFont *font;
   FontStruct_t fontStruct;
   const char *fmt, *family;
 
   family = fa->fFamily;
   if (!family) {
      family = "*";
   }
   pixelsize = -fa->fPointsize;
 
   if (pixelsize < 0) {
      double d;
      d = -pixelsize * 25.4/72;
      Int_t xx; Int_t yy; UInt_t ww; UInt_t hh;
      gVirtualX->GetWindowSize(gVirtualX->GetDefaultRootWindow(), xx, yy, ww, hh);
      d *= ww;
 
      d /= gVirtualX->ScreenWidthMM();
      d += 0.5;
      pixelsize = (int) d;
   }
 
   // Couldn't find exact match. Now fall back to other available physical fonts.
 
   fmt = "-*-%.240s-*-*-*-*-*-*-*-*-*-*-*-*";
   buf = TString::Format(fmt, family);
   nameList = gVirtualX->ListFonts(buf.Data(), 32768, numNames);
   if (!numNames) {
      // Try getting some system font.
 
      buf = TString::Format(fmt, "fixed");
      // coverity[returned_null]
      // coverity[dereference]
      nameList = gVirtualX->ListFonts(buf.Data(), 32768, numNames);
 
      if (!numNames) {
 
getsystem:
         fontStruct = gVirtualX->LoadQueryFont("fixed");
 
         if (!fontStruct) {
            fontStruct = gVirtualX->LoadQueryFont("*");
            if (!fontStruct) {
               return 0;
            }
         }
         goto end;
      }
   }
 
   // Inspect each of the XLFDs and pick the one that most closely
   // matches the desired attributes.
 
   bestIdx = 0;
   bestScore = kMaxInt;
   bestScaleableIdx = 0;
   bestScaleableScore = kMaxInt;
 
   for (i = 0; i < numNames; i++) {
      score = 0;
      scaleable = 0;
      if (!ParseXLFD(nameList[i], &xa)) {
         continue;
      }
      xaPixelsize = -xa.fFA.fPointsize;
 
      // Since most people used to use -adobe-* in their XLFDs,
      // preserve the preference for "adobe" foundry. Otherwise
      // some applications looks may change slightly if another foundry
      // is chosen.
 
      if (xa.fFoundry && (strcasecmp(xa.fFoundry, "adobe") != 0)) {
         score += 3000;
      }
      if (!xa.fFA.fPointsize) {
 
         // A scaleable font is almost always acceptable, but the
         // corresponding bitmapped font would be better.
 
         score += 10;
         scaleable = 1;
      } else {
 
         // A font that is too small is better than one that is too big.
 
         if (xaPixelsize > pixelsize) {
            score += (xaPixelsize - pixelsize) * 120;
         } else {
            score += (pixelsize - xaPixelsize) * 100;
         }
      }
 
      score += TMath::Abs(xa.fFA.fWeight - fa->fWeight) * 30;
      score += TMath::Abs(xa.fFA.fSlant - fa->fSlant) * 25;
 
      if (xa.fSlant == kFontSlantOblique) {
 
         // Italic fonts are preferred over oblique.
 
         //score += 4;
      }
      if (xa.fSetwidth != kFontSWNormal) {
 
         // The normal setwidth is highly preferred.
 
         score += 2000;
      }
      if (xa.fCharset == kFontCSOther) {
 
         // The standard character set is highly preferred over
         // foreign languages charsets (because we don't support
         // other languages yet).
 
         score += 11000;
      }
      if ((xa.fCharset == kFontCSNormal) && (xa.fEncoding != 1)) {
 
         // The '1' encoding for the characters above 0x7f is highly
         // preferred over the other encodings.
 
         score += 8000;
      }
      if (scaleable) {
         if (score < bestScaleableScore) {
            bestScaleableIdx = i;
            bestScaleableScore = score;
         }
      } else {
         if (score < bestScore) {
            bestIdx = i;
            bestScore = score;
         }
      }
      if (!score) {
         break;
      }
   }
 
   // Now we know which is the closest matching scaleable font and the
   // closest matching bitmapped font. If the scaleable font was a
   // better match, try getting the scaleable font; however, if the
   // scalable font was not actually available in the desired pointsize,
   // fall back to the closest bitmapped font.
 
   fontStruct = 0;
 
   if (bestScaleableScore < bestScore) {
      char *str, *rest;
 
      // Fill in the desired pointsize info for this font.
 
tryscale:
      str = nameList[bestScaleableIdx];
      for (i = 0; i < XLFD_PIXEL_SIZE - 1; i++) {
         str = strchr(str + 1, '-');
      }
      rest = str;
      for (i = XLFD_PIXEL_SIZE - 1; i < XLFD_REGISTRY; i++) {
         rest = strchr(rest + 1, '-');
      }
      *str = '\0';
      buf = TString::Format("%.240s-*-%d-*-*-*-*-*%s", nameList[bestScaleableIdx], pixelsize, rest);
      *str = '-';
      fontStruct = gVirtualX->LoadQueryFont(buf.Data());
      bestScaleableScore = kMaxInt;
   }
   if (!fontStruct) {
      buf = nameList[bestIdx];
      fontStruct = gVirtualX->LoadQueryFont(buf.Data());
 
      if (!fontStruct) {
 
         // This shouldn't happen because the font name is one of the
         // names that X gave us to use, but it does anyhow.
 
         if (bestScaleableScore < kMaxInt) {
            goto tryscale;
         } else {
            gVirtualX->FreeFontNames(nameList);
            goto getsystem;
         }
      }
   }
   gVirtualX->FreeFontNames(nameList);
 
end:
   font = MakeFont(fontPtr, fontStruct, buf);
   font->fFA.fUnderline = fa->fUnderline;
   font->fFA.fOverstrike = fa->fOverstrike;
 
   return font;
}
 
////////////////////////////////////////////////////////////////////////////////
/// The return value is a pointer to an TGFont object that represents the
/// native font. If a native font by the given name could not be found,
/// the return value is NULL.
///
/// Every call to this procedure returns a new TGFont object, even if the
/// name has already been seen before. The caller should call FreeFont
/// when the font is no longer needed.
 
TGFont *TGFontPool::GetNativeFont(const char *name, Bool_t fixedDefault)
{
   FontStruct_t fontStruct;
   fixedDefault = fixedDefault && ((*name == '-') || (*name == '*'));
   fontStruct = fClient->GetFontByName(name, fixedDefault);
 
   if (!fontStruct) {
      return 0;
   }
 
   return MakeFont(0, fontStruct, name);
}
 
////////////////////////////////////////////////////////////////////////////////
/// Helper for GetNativeFont() and GetFontFromAttributes(). Creates and
/// initializes a new TGFont object.
///
/// font       -- If non-NULL, store the information in this existing TGFont
///               object, rather than creating a new one; the existing
///               contents of the font will be released. If NULL, a new
///               TGFont object is created.
/// fontStruct -- information about font.
/// fontName   -- The string passed to TVirtualX::LoadQueryFont() to construct the
///               fontStruct.
 
TGFont *TGFontPool::MakeFont(TGFont *font, FontStruct_t fontStruct,
                             const char *fontName)
{
   TGFont *newFont;
 
   Int_t i, width, firstChar, lastChar, n, replaceOK;
   char *p;
   char buf[4];
   XLFDAttributes_t xa;
 
   if (font) {
      gVirtualX->FreeFontStruct(font->fFontStruct);
      newFont = font;
   } else {
      newFont = new TGFont(fontName);
   }
 
   if (!ParseXLFD(fontName, &xa)) {
      newFont->fFA.fFamily = GetUid(fontName);
   } else {
      newFont->fFA = xa.fFA;
   }
 
   if (newFont->fFA.fPointsize < 0) {
      double d;
      Int_t xx; Int_t yy; UInt_t ww; UInt_t hh;
      gVirtualX->GetWindowSize(gVirtualX->GetDefaultRootWindow(), xx, yy, ww, hh);
      d = -newFont->fFA.fPointsize * 72/25.4;
      d *= gVirtualX->ScreenWidthMM();
      d /= ww;
      d += 0.5;
      newFont->fFA.fPointsize = (int) d;
   }
 
   Int_t ascent;
   Int_t descent;
   gVirtualX->GetFontProperties(fontStruct, ascent, descent);
 
   newFont->fFM.fAscent = ascent;
   newFont->fFM.fDescent = descent;
   newFont->fFM.fLinespace = ascent + descent;
   newFont->fFM.fMaxWidth = gVirtualX->TextWidth(fontStruct, "@", 1);
   newFont->fFM.fFixed = kTRUE;
   newFont->fFontStruct = fontStruct;
   newFont->fFontH      = gVirtualX->GetFontHandle(fontStruct);
 
   // Classify the characters.
 
   firstChar = 0x20; //fontStruct->min_char_or_byte2;
   lastChar = 0xff; //fontStruct->max_char_or_byte2;
 
   for (i = 0; i < 256; i++) {
      if ((i == 160) || (i == 173) || (i == 177) ||
          (i < firstChar) || (i > lastChar)) {
         newFont->fTypes[i] = kCharReplace;
      } else {
         newFont->fTypes[i] = kCharNormal;
      }
   }
 
   // Compute the widths for all the normal characters. Any other
   // characters are given an initial width of 0. Also, this determines
   // if this is a fixed or variable width font, by comparing the widths
   // of all the normal characters.
 
   char ch[2] = {0, 0};
   width = 0;
   for (i = 0; i < 256; i++) {
      if (newFont->fTypes[i] != kCharNormal) {
         n = 0;
      } else {
         ch[0] = i;
         n = gVirtualX->TextWidth(fontStruct, ch, 1);
      }
      newFont->fWidths[i] = n;
      if (n) {
         if (!width) {
            width = n;
         } else if (width != n) {
            newFont->fFM.fFixed = kFALSE;
         }
      }
   }
 
   // Compute the widths of the characters that should be replaced with
   // control character expansions. If the appropriate chars are not
   // available in this font, then control character expansions will not
   // be used; control chars will be invisible & zero-width.
 
   replaceOK = kTRUE;
   for (p = gHexChars; *p != '\0'; p++) {
      if ((UChar_t(*p) < firstChar) || (UChar_t(*p) > lastChar)) {
         replaceOK = kFALSE;
         break;
      }
   }
   for (i = 0; i < 256; i++) {
      if (newFont->fTypes[i] == kCharReplace) {
         if (replaceOK) {
            n = GetControlCharSubst(i, buf);
            for (; --n >= 0;) {
               newFont->fWidths[i] += newFont->fWidths[UChar_t(buf[n])];
            }
         } else {
            newFont->fTypes[i] = kCharSkip;
         }
      }
   }
 
   newFont->fUnderlinePos = descent >> 1;
   newFont->fBarHeight = newFont->fWidths[(int)'I']/3;
 
   if (newFont->fBarHeight == 0) {
      newFont->fBarHeight = 1;
   }
 
   if (newFont->fUnderlinePos + newFont->fBarHeight > descent) {
 
      // If this set of cobbled together values would cause the bottom of
      // the underline bar to stick below the descent of the font, jack
      // the underline up a bit higher.
 
      newFont->fBarHeight = descent - newFont->fUnderlinePos;
 
      if (!newFont->fBarHeight) {
         newFont->fUnderlinePos--;
         newFont->fBarHeight = 1;
      }
   }
 
   return newFont;
}
 
////////////////////////////////////////////////////////////////////////////////
/// When displaying text in a widget, a backslashed escape sequence is
/// substituted for control characters that occur in the text. Given a
/// control character, fill in a buffer with the replacement string that
/// should be displayed.
///
/// The return value is the length of the substitute string, buf is
/// filled with the substitute string; it is not '\0' terminated.
///
/// c   -- The control character to be replaced.
/// buf -- Buffer that gets replacement string. It only needs to be
///        4 characters long.
 
static Int_t GetControlCharSubst(Int_t c, char buf[4])
{
   buf[0] = '\\';
 
   if (((UInt_t)c < sizeof(gMapChars)) && (gMapChars[c] != 0)) {
      buf[1] = gMapChars[c];
      return 2;
   } else {
      buf[1] = 'x';
      buf[2] = gHexChars[(c >> 4) & 0xf];
      buf[3] = gHexChars[c & 0xf];
      return 4;
   }
}