src/c_tk_base_7_5_w_mods/tkfont.c

/* $Header$ */

/* 
 * tkFont.c --
 *
 *      This file maintains a database of fonts for the Tk toolkit.
 *      It also provides several utility procedures for measuring and
 *      displaying text.
 *
 * Copyright (c) 1990-1994 The Regents of the University of California.
 * Copyright (c) 1994-1998 Sun Microsystems, Inc.
 *
 * See the file "license.terms" for information on usage and redistribution
 * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 *
 * RCS: @(#) $Id: tkfont.c,v 1.1.1.1 2001/06/13 05:00:58 dtashley Exp $
 */

#include "tkPort.h"
#include "tkInt.h"
#include "tkFont.h"

/*
 * The following structure is used to keep track of all the fonts that
 * exist in the current application.  It must be stored in the
 * TkMainInfo for the application.
 */
 
typedef struct TkFontInfo {
    Tcl_HashTable fontCache;    /* Map a string to an existing Tk_Font.
                                 * Keys are string font names, values are
                                 * TkFont pointers. */
    Tcl_HashTable namedTable;   /* Map a name to a set of attributes for a
                                 * font, used when constructing a Tk_Font from
                                 * a named font description.  Keys are
                                 * strings, values are NamedFont pointers. */
    TkMainInfo *mainPtr;        /* Application that owns this structure. */
    int updatePending;          /* Non-zero when a World Changed event has
                                 * already been queued to handle a change to
                                 * a named font. */
} TkFontInfo;

/*
 * 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.
 */

typedef struct NamedFont {
    int refCount;               /* Number of users of named font. */
    int deletePending;          /* Non-zero if font should be deleted when
                                 * last reference goes away. */
    TkFontAttributes fa;        /* Desired attributes for named font. */
} NamedFont;
    
/*
 * The following two structures are used to keep track of string
 * measurement information when using the text layout facilities.
 *
 * A LayoutChunk 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.
 *
 * A TextLayout is a collection of LayoutChunks.  It can be displayed with
 * respect to any origin.  It is the implementation of the Tk_TextLayout
 * opaque token.
 */

typedef struct LayoutChunk {
    CONST char *start;          /* Pointer to simple string to be displayed.
                                 * This is a pointer into the TkTextLayout's
                                 * string. */
    int numBytes;               /* The number of bytes in this chunk. */
    int numChars;               /* The number of characters in this chunk. */
    int numDisplayChars;        /* 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 x, y;                   /* The origin of the first character in this
                                 * chunk with respect to the upper-left hand
                                 * corner of the TextLayout. */
    int totalWidth;             /* Width in pixels of this chunk.  Used
                                 * when hit testing the invisible spaces at
                                 * the end of a chunk. */
    int displayWidth;           /* 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. */
} LayoutChunk;

typedef struct TextLayout {
    Tk_Font tkfont;             /* The font used when laying out the text. */
    CONST char *string;         /* The string that was layed out. */
    int width;                  /* The maximum width of all lines in the
                                 * text layout. */
    int numChunks;              /* Number of chunks actually used in
                                 * following array. */
    LayoutChunk chunks[1];      /* Array of chunks.  The actual size will
                                 * be maxChunks.  THIS FIELD MUST BE THE LAST
                                 * IN THE STRUCTURE. */
} TextLayout;

/*
 * The following structures are used as two-way maps between the values for
 * the fields in the TkFontAttributes structure and the strings used in
 * Tcl, when parsing both option-value format and style-list format font
 * name strings.
 */

static TkStateMap weightMap[] = {
    {TK_FW_NORMAL,      "normal"},
    {TK_FW_BOLD,        "bold"},
    {TK_FW_UNKNOWN,     NULL}
};

static TkStateMap slantMap[] = {
    {TK_FS_ROMAN,       "roman"},
    {TK_FS_ITALIC,      "italic"},
    {TK_FS_UNKNOWN,     NULL}
};

static TkStateMap underlineMap[] = {
    {1,                 "underline"},
    {0,                 NULL}
};

static TkStateMap overstrikeMap[] = {
    {1,                 "overstrike"},
    {0,                 NULL}
};

/*
 * The following structures are used when parsing XLFD's into a set of
 * TkFontAttributes.
 */

static TkStateMap xlfdWeightMap[] = {
    {TK_FW_NORMAL,      "normal"},
    {TK_FW_NORMAL,      "medium"},
    {TK_FW_NORMAL,      "book"},
    {TK_FW_NORMAL,      "light"},
    {TK_FW_BOLD,        "bold"},
    {TK_FW_BOLD,        "demi"},
    {TK_FW_BOLD,        "demibold"},
    {TK_FW_NORMAL,      NULL}           /* Assume anything else is "normal". */
}; 

static TkStateMap xlfdSlantMap[] = {
    {TK_FS_ROMAN,       "r"},
    {TK_FS_ITALIC,      "i"},
    {TK_FS_OBLIQUE,     "o"},
    {TK_FS_ROMAN,       NULL}           /* Assume anything else is "roman". */
};

static TkStateMap xlfdSetwidthMap[] = {
    {TK_SW_NORMAL,      "normal"},
    {TK_SW_CONDENSE,    "narrow"},
    {TK_SW_CONDENSE,    "semicondensed"},
    {TK_SW_CONDENSE,    "condensed"},
    {TK_SW_UNKNOWN,     NULL}
};

/*
 * The following structure and defines specify the valid builtin options 
 * when configuring a set of font attributes.
 */

static char *fontOpt[] = {
    "-family",
    "-size",
    "-weight",
    "-slant",
    "-underline",
    "-overstrike",
    NULL
};

#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

/*
 * Hardcoded font aliases.  These are used to describe (mostly) identical
 * fonts whose names differ from platform to platform.  If the
 * user-supplied font name matches any of the names in one of the alias
 * lists, the other names in the alias list are also automatically tried.
 */

static char *timesAliases[] = {
    "Times",                    /* Unix. */
    "Times New Roman",          /* Windows. */
    "New York",                 /* Mac. */
    NULL
};

static char *helveticaAliases[] = {
    "Helvetica",                /* Unix. */
    "Arial",                    /* Windows. */
    "Geneva",                   /* Mac. */
    NULL
};

static char *courierAliases[] = {
    "Courier",                  /* Unix and Mac. */
    "Courier New",              /* Windows. */
    NULL
};

static char *minchoAliases[] = {
    "mincho",                   /* Unix. */
    "\357\274\255\357\274\263 \346\230\216\346\234\235",
                                /* Windows (MS mincho). */
    "\346\234\254\346\230\216\346\234\235\342\210\222\357\274\255",
                                /* Mac (honmincho-M). */
    NULL
};

static char *gothicAliases[] = {
    "gothic",                   /* Unix. */
    "\357\274\255\357\274\263 \343\202\264\343\202\267\343\203\203\343\202\257",
                                /* Windows (MS goshikku). */
    "\344\270\270\343\202\264\343\202\267\343\203\203\343\202\257\342\210\222\357\274\255",
                                /* Mac (goshikku-M). */
    NULL    
};

static char *dingbatsAliases[] = {
    "dingbats", "zapfdingbats", "itc zapfdingbats",
                                /* Unix. */
                                /* Windows. */
    "zapf dingbats",            /* Mac. */
    NULL
};

static char **fontAliases[] = {
    timesAliases,
    helveticaAliases,
    courierAliases,
    minchoAliases,
    gothicAliases,
    dingbatsAliases,
    NULL
};  

/*
 * Hardcoded font classes.  If the character cannot be found in the base 
 * font, the classes are examined in order to see if some other similar 
 * font should be examined also.  
 */

static char *systemClass[] = {
    "fixed",                            /* Unix. */
                                        /* Windows. */
    "chicago", "osaka", "sistemny",     /* Mac. */
    NULL
};

static char *serifClass[] = {
    "times", "palatino", "mincho",      /* All platforms. */
    "song ti",                          /* Unix. */
    "ms serif", "simplified arabic",    /* Windows. */
    "latinski",                         /* Mac. */
    NULL
};

static char *sansClass[] = {
    "helvetica", "gothic",              /* All platforms. */
                                        /* Unix. */
    "ms sans serif", "traditional arabic",
                                        /* Windows. */
    "bastion",                          /* Mac. */
    NULL
};

static char *monoClass[] = {
    "courier", "gothic",                /* All platforms. */
    "fangsong ti",                      /* Unix. */
    "simplified arabic fixed",          /* Windows. */
    "monaco", "pryamoy",                /* Mac. */
    NULL
};

static char *symbolClass[] = {
    "symbol", "dingbats", "wingdings", NULL
};

static char **fontFallbacks[] = {
    systemClass,
    serifClass,
    sansClass,
    monoClass,
    symbolClass,
    NULL
};

/*
 * Global fallbacks.  If the character could not be found in the preferred
 * fallback list, this list is examined.  If the character still cannot be
 * found, all font families in the system are examined. 
 */

static char *globalFontClass[] = {
    "symbol",                   /* All platforms. */
                                /* Unix. */
    "lucida sans unicode",      /* Windows. */
    "bitstream cyberbit",       /* Windows popular CJK font */
    "chicago",                  /* Mac. */
    NULL
};

#define GetFontAttributes(tkfont) \
                ((CONST TkFontAttributes *) &((TkFont *) (tkfont))->fa)

#define GetFontMetrics(tkfont)    \
                ((CONST TkFontMetrics *) &((TkFont *) (tkfont))->fm)


static int              ConfigAttributesObj _ANSI_ARGS_((Tcl_Interp *interp,
                            Tk_Window tkwin, int objc, Tcl_Obj *CONST objv[],
                            TkFontAttributes *faPtr));
static int              CreateNamedFont _ANSI_ARGS_((Tcl_Interp *interp,
                            Tk_Window tkwin, CONST char *name,
                            TkFontAttributes *faPtr));
static void             DupFontObjProc _ANSI_ARGS_((Tcl_Obj *srcObjPtr,
                            Tcl_Obj *dupObjPtr));
static int              FieldSpecified _ANSI_ARGS_((CONST char *field));
static void             FreeFontObjProc _ANSI_ARGS_((Tcl_Obj *objPtr));
static int              GetAttributeInfoObj _ANSI_ARGS_((Tcl_Interp *interp,
                            CONST TkFontAttributes *faPtr, Tcl_Obj *objPtr));
static LayoutChunk *    NewChunk _ANSI_ARGS_((TextLayout **layoutPtrPtr,
                            int *maxPtr, CONST char *start, int numChars,
                            int curX, int newX, int y));
static int              ParseFontNameObj _ANSI_ARGS_((Tcl_Interp *interp,
                            Tk_Window tkwin, Tcl_Obj *objPtr,
                            TkFontAttributes *faPtr));
static void             RecomputeWidgets _ANSI_ARGS_((TkWindow *winPtr));
static int              SetFontFromAny _ANSI_ARGS_((Tcl_Interp *interp,
                            Tcl_Obj *objPtr));
static void             TheWorldHasChanged _ANSI_ARGS_((
                            ClientData clientData));
static void             UpdateDependentFonts _ANSI_ARGS_((TkFontInfo *fiPtr,
                            Tk_Window tkwin, Tcl_HashEntry *namedHashPtr));

/*
 * The following structure defines the implementation of the "font" Tcl
 * object, used for drawing. The internalRep.twoPtrValue.ptr1 field of
 * each font object points to the TkFont structure for the font, or
 * NULL.
 */

static Tcl_ObjType fontObjType = {
    "font",                     /* name */
    FreeFontObjProc,            /* freeIntRepProc */
    DupFontObjProc,             /* dupIntRepProc */
    NULL,                       /* updateStringProc */
    SetFontFromAny              /* setFromAnyProc */
};


/*
 *---------------------------------------------------------------------------
 *
 * TkFontPkgInit --
 *
 *      This procedure is called when an application is created.  It
 *      initializes all the structures that are used by the font
 *      package on a per application basis.
 *
 * Results:
 *      Stores a token in the mainPtr to hold information needed by this 
 *      package on a per application basis. 
 *
 * Side effects:
 *      Memory allocated.
 *
 *---------------------------------------------------------------------------
 */
void
TkFontPkgInit(mainPtr)
    TkMainInfo *mainPtr;        /* The application being created. */
{
    TkFontInfo *fiPtr;

    fiPtr = (TkFontInfo *) ckalloc(sizeof(TkFontInfo));
    Tcl_InitHashTable(&fiPtr->fontCache, TCL_STRING_KEYS);
    Tcl_InitHashTable(&fiPtr->namedTable, TCL_STRING_KEYS);
    fiPtr->mainPtr = mainPtr;
    fiPtr->updatePending = 0;
    mainPtr->fontInfoPtr = fiPtr;

    TkpFontPkgInit(mainPtr);
}

/*
 *---------------------------------------------------------------------------
 *
 * TkFontPkgFree --
 *
 *      This procedure is called when an application is deleted.  It
 *      deletes all the structures that were used by the font package
 *      for this application.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      Memory freed.
 *
 *---------------------------------------------------------------------------
 */

void
TkFontPkgFree(mainPtr)
    TkMainInfo *mainPtr;        /* The application being deleted. */
{
    TkFontInfo *fiPtr;
    Tcl_HashEntry *hPtr, *searchPtr;
    Tcl_HashSearch search;
    int fontsLeft;

    fiPtr = mainPtr->fontInfoPtr;

    fontsLeft = 0;
    for (searchPtr = Tcl_FirstHashEntry(&fiPtr->fontCache, &search);
            searchPtr != NULL;
            searchPtr = Tcl_NextHashEntry(&search)) {
        fontsLeft++;
        fprintf(stderr, "Font %s still in cache.\n", 
                Tcl_GetHashKey(&fiPtr->fontCache, searchPtr));
    }
    if (fontsLeft) {
        panic("TkFontPkgFree: all fonts should have been freed already");
    }
    Tcl_DeleteHashTable(&fiPtr->fontCache);

    hPtr = Tcl_FirstHashEntry(&fiPtr->namedTable, &search);
    while (hPtr != NULL) {
        ckfree((char *) Tcl_GetHashValue(hPtr));
        hPtr = Tcl_NextHashEntry(&search);
    }
    Tcl_DeleteHashTable(&fiPtr->namedTable);
    if (fiPtr->updatePending != 0) {
        Tcl_CancelIdleCall(TheWorldHasChanged, (ClientData) fiPtr);
    }
    ckfree((char *) fiPtr);
}

/*
 *---------------------------------------------------------------------------
 *
 * Tk_FontObjCmd -- 
 *
 *      This procedure is implemented to process the "font" Tcl command.
 *      See the user documentation for details on what it does.
 *
 * Results:
 *      A standard Tcl result.
 *
 * Side effects:
 *      See the user documentation.
 *
 *----------------------------------------------------------------------
 */

int
Tk_FontObjCmd(clientData, interp, objc, objv)
    ClientData clientData;      /* Main window associated with interpreter. */
    Tcl_Interp *interp;         /* Current interpreter. */
    int objc;                   /* Number of arguments. */
    Tcl_Obj *CONST objv[];      /* Argument objects. */
{
    int index;
    Tk_Window tkwin;
    TkFontInfo *fiPtr;
    static char *optionStrings[] = {
        "actual",       "configure",    "create",       "delete",
        "families",     "measure",      "metrics",      "names",
        NULL
    };
    enum options {
        FONT_ACTUAL,    FONT_CONFIGURE, FONT_CREATE,    FONT_DELETE,
        FONT_FAMILIES,  FONT_MEASURE,   FONT_METRICS,   FONT_NAMES
    };

    tkwin = (Tk_Window) clientData;
    fiPtr = ((TkWindow *) tkwin)->mainPtr->fontInfoPtr;

    if (objc < 2) {
        Tcl_WrongNumArgs(interp, 1, objv, "option ?arg?");
        return TCL_ERROR;
    }
    if (Tcl_GetIndexFromObj(interp, objv[1], optionStrings, "option", 0,
            &index) != TCL_OK) {
        return TCL_ERROR;
    }

    switch ((enum options) index) {
        case FONT_ACTUAL: {
            int skip, result;
            Tk_Font tkfont;
            Tcl_Obj *objPtr;
            CONST TkFontAttributes *faPtr;

            skip = TkGetDisplayOf(interp, objc - 3, objv + 3, &tkwin);
            if (skip < 0) {
                return TCL_ERROR;
            }
            if ((objc < 3) || (objc - skip > 4)) {
                Tcl_WrongNumArgs(interp, 2, objv,
                        "font ?-displayof window? ?option?");
                return TCL_ERROR;
            }
            tkfont = Tk_AllocFontFromObj(interp, tkwin, objv[2]);
            if (tkfont == NULL) {
                return TCL_ERROR;
            }
            objc -= skip;
            objv += skip;
            faPtr = GetFontAttributes(tkfont);
            objPtr = NULL;
            if (objc > 3) {
                objPtr = objv[3];
            }
            result = GetAttributeInfoObj(interp, faPtr, objPtr);
            Tk_FreeFont(tkfont);
            return result;
        }
        case FONT_CONFIGURE: {
            int result;
            char *string;
            Tcl_Obj *objPtr;
            NamedFont *nfPtr;
            Tcl_HashEntry *namedHashPtr;

            if (objc < 3) {
                Tcl_WrongNumArgs(interp, 2, objv, "fontname ?options?");
                return TCL_ERROR;
            }
            string = Tcl_GetString(objv[2]);
            namedHashPtr = Tcl_FindHashEntry(&fiPtr->namedTable, string);
            nfPtr = NULL;               /* lint. */
            if (namedHashPtr != NULL) {
                nfPtr = (NamedFont *) Tcl_GetHashValue(namedHashPtr);
            }
            if ((namedHashPtr == NULL) || (nfPtr->deletePending != 0)) {
                Tcl_AppendResult(interp, "named font \"", string,
                        "\" doesn't exist", NULL);
                return TCL_ERROR;
            }
            if (objc == 3) {
                objPtr = NULL;
            } else if (objc == 4) {
                objPtr = objv[3];
            } else {
                result = ConfigAttributesObj(interp, tkwin, objc - 3,
                        objv + 3, &nfPtr->fa);
                UpdateDependentFonts(fiPtr, tkwin, namedHashPtr);
                return result;
            }
            return GetAttributeInfoObj(interp, &nfPtr->fa, objPtr);
        }
        case FONT_CREATE: {
            int skip, i;
            char *name;
            char buf[16 + TCL_INTEGER_SPACE];
            TkFontAttributes fa;
            Tcl_HashEntry *namedHashPtr;

            skip = 3;
            if (objc < 3) {
                name = NULL;
            } else {
                name = Tcl_GetString(objv[2]);
                if (name[0] == '-') {
                    name = NULL;
                }
            }
            if (name == NULL) {
                /*
                 * No font name specified.  Generate one of the form "fontX".
                 */

                for (i = 1; ; i++) {
                    sprintf(buf, "font%d", i);
                    namedHashPtr = Tcl_FindHashEntry(&fiPtr->namedTable, buf);
                    if (namedHashPtr == NULL) {
                        break;
                    }
                }
                name = buf;
                skip = 2;
            }
            TkInitFontAttributes(&fa);
            if (ConfigAttributesObj(interp, tkwin, objc - skip, objv + skip,
                    &fa) != TCL_OK) {
                return TCL_ERROR;
            }
            if (CreateNamedFont(interp, tkwin, name, &fa) != TCL_OK) {
                return TCL_ERROR;
            }
            Tcl_AppendResult(interp, name, NULL);
            break;
        }
        case FONT_DELETE: {
            int i;
            char *string;
            NamedFont *nfPtr;
            Tcl_HashEntry *namedHashPtr;

            /*
             * Delete the named font.  If there are still widgets using this
             * font, then it isn't deleted right away.
             */

            if (objc < 3) {
                Tcl_WrongNumArgs(interp, 2, objv, "fontname ?fontname ...?");
                return TCL_ERROR;
            }
            for (i = 2; i < objc; i++) {
                string = Tcl_GetString(objv[i]);
                namedHashPtr = Tcl_FindHashEntry(&fiPtr->namedTable, string);
                if (namedHashPtr == NULL) {
                    Tcl_AppendResult(interp, "named font \"", string,
                            "\" doesn't exist", (char *) NULL);
                    return TCL_ERROR;
                }
                nfPtr = (NamedFont *) Tcl_GetHashValue(namedHashPtr);
                if (nfPtr->refCount != 0) {
                    nfPtr->deletePending = 1;
                } else {
                    Tcl_DeleteHashEntry(namedHashPtr);
                    ckfree((char *) nfPtr);
                }
            }
            break;
        }
        case FONT_FAMILIES: {
            int skip;

            skip = TkGetDisplayOf(interp, objc - 2, objv + 2, &tkwin);
            if (skip < 0) {
                return TCL_ERROR;
            }
            if (objc - skip != 2) {
                Tcl_WrongNumArgs(interp, 2, objv, "?-displayof window?");
                return TCL_ERROR;
            }
            TkpGetFontFamilies(interp, tkwin);
            break;
        }
        case FONT_MEASURE: {
            char *string;
            Tk_Font tkfont;
            int length, skip;
            Tcl_Obj *resultPtr;
            
            skip = TkGetDisplayOf(interp, objc - 3, objv + 3, &tkwin);
            if (skip < 0) {
                return TCL_ERROR;
            }
            if (objc - skip != 4) {
                Tcl_WrongNumArgs(interp, 2, objv,
                        "font ?-displayof window? text");
                return TCL_ERROR;
            }
            tkfont = Tk_AllocFontFromObj(interp, tkwin, objv[2]);
            if (tkfont == NULL) {
                return TCL_ERROR;
            }
            string = Tcl_GetStringFromObj(objv[3 + skip], &length);
            resultPtr = Tcl_GetObjResult(interp);
            Tcl_SetIntObj(resultPtr, Tk_TextWidth(tkfont, string, length));
            Tk_FreeFont(tkfont);
            break;
        }
        case FONT_METRICS: {
            Tk_Font tkfont;
            int skip, index, i;
            CONST TkFontMetrics *fmPtr;
            static char *switches[] = {
                "-ascent", "-descent", "-linespace", "-fixed", NULL
            };

            skip = TkGetDisplayOf(interp, objc - 3, objv + 3, &tkwin);
            if (skip < 0) {
                return TCL_ERROR;
            }
            if ((objc < 3) || ((objc - skip) > 4)) {
                Tcl_WrongNumArgs(interp, 2, objv,
                        "font ?-displayof window? ?option?");
                return TCL_ERROR;
            }
            tkfont = Tk_AllocFontFromObj(interp, tkwin, objv[2]);
            if (tkfont == NULL) {
                return TCL_ERROR;
            }
            objc -= skip;
            objv += skip;
            fmPtr = GetFontMetrics(tkfont);
            if (objc == 3) {
                char buf[64 + TCL_INTEGER_SPACE * 4];

                sprintf(buf, "-ascent %d -descent %d -linespace %d -fixed %d",
                        fmPtr->ascent, fmPtr->descent,
                        fmPtr->ascent + fmPtr->descent,
                        fmPtr->fixed);
                Tcl_AppendResult(interp, buf, NULL);
            } else {
                if (Tcl_GetIndexFromObj(interp, objv[3], switches,
                        "metric", 0, &index) != TCL_OK) {
                    Tk_FreeFont(tkfont);
                    return TCL_ERROR;
                }
                i = 0;                  /* Needed only to prevent compiler
                                         * warning. */
                switch (index) {
                    case 0: i = fmPtr->ascent;                  break;
                    case 1: i = fmPtr->descent;                 break;
                    case 2: i = fmPtr->ascent + fmPtr->descent; break;
                    case 3: i = fmPtr->fixed;                   break;
                }
                Tcl_SetIntObj(Tcl_GetObjResult(interp), i);
            }
            Tk_FreeFont(tkfont);
            break;
        }
        case FONT_NAMES: {
            char *string;
            NamedFont *nfPtr;
            Tcl_HashSearch search;
            Tcl_HashEntry *namedHashPtr;
            Tcl_Obj *strPtr, *resultPtr;
            
            if (objc != 2) {
                Tcl_WrongNumArgs(interp, 1, objv, "names");
                return TCL_ERROR;
            }
            resultPtr = Tcl_GetObjResult(interp);
            namedHashPtr = Tcl_FirstHashEntry(&fiPtr->namedTable, &search);
            while (namedHashPtr != NULL) {
                nfPtr = (NamedFont *) Tcl_GetHashValue(namedHashPtr);
                if (nfPtr->deletePending == 0) {
                    string = Tcl_GetHashKey(&fiPtr->namedTable, namedHashPtr);
                    strPtr = Tcl_NewStringObj(string, -1);
                    Tcl_ListObjAppendElement(NULL, resultPtr, strPtr);
                }
                namedHashPtr = Tcl_NextHashEntry(&search);
            }
            break;
        }
    }
    return TCL_OK;
}

/*
 *---------------------------------------------------------------------------
 *
 * UpdateDependentFonts, TheWorldHasChanged, RecomputeWidgets --
 *
 *      Called when the attributes of a named font changes.  Updates all
 *      the instantiated fonts that depend on that named font and then
 *      uses the brute force approach and prepares every widget to
 *      recompute its geometry.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      Things get queued for redisplay.
 *
 *---------------------------------------------------------------------------
 */

static void
UpdateDependentFonts(fiPtr, tkwin, namedHashPtr)
    TkFontInfo *fiPtr;          /* Info about application's fonts. */
    Tk_Window tkwin;            /* A window in the application. */
    Tcl_HashEntry *namedHashPtr;/* The named font that is changing. */
{
    Tcl_HashEntry *cacheHashPtr;
    Tcl_HashSearch search;
    TkFont *fontPtr;
    NamedFont *nfPtr;

    nfPtr = (NamedFont *) Tcl_GetHashValue(namedHashPtr);
    if (nfPtr->refCount == 0) {
        /*
         * Well nobody's using this named font, so don't have to tell
         * any widgets to recompute themselves.
         */

        return;
    }

    cacheHashPtr = Tcl_FirstHashEntry(&fiPtr->fontCache, &search);
    while (cacheHashPtr != NULL) {
        for (fontPtr = (TkFont *) Tcl_GetHashValue(cacheHashPtr);
                fontPtr != NULL; fontPtr = fontPtr->nextPtr) {
            if (fontPtr->namedHashPtr == namedHashPtr) {
                TkpGetFontFromAttributes(fontPtr, tkwin, &nfPtr->fa);
                if (fiPtr->updatePending == 0) {
                    fiPtr->updatePending = 1;
                    Tcl_DoWhenIdle(TheWorldHasChanged, (ClientData) fiPtr);
                }
            }
        }
        cacheHashPtr = Tcl_NextHashEntry(&search);
    }
}

static void
TheWorldHasChanged(clientData)
    ClientData clientData;      /* Info about application's fonts. */
{
    TkFontInfo *fiPtr;

    fiPtr = (TkFontInfo *) clientData;
    fiPtr->updatePending = 0;

    RecomputeWidgets(fiPtr->mainPtr->winPtr);
}

static void
RecomputeWidgets(winPtr)
    TkWindow *winPtr;           /* Window to which command is sent. */
{
    if ((winPtr->classProcsPtr != NULL)
            && (winPtr->classProcsPtr->geometryProc != NULL)) {
        (*winPtr->classProcsPtr->geometryProc)(winPtr->instanceData);
    }
    for (winPtr = winPtr->childList; winPtr != NULL; winPtr = winPtr->nextPtr) {
        RecomputeWidgets(winPtr);
    }
}

/*
 *---------------------------------------------------------------------------
 *
 * CreateNamedFont --
 *
 *      Create the specified named font with the given attributes in the
 *      named font table associated with the interp.  
 *
 * Results:
 *      Returns TCL_OK if the font was successfully created, or TCL_ERROR
 *      if the named font already existed.  If TCL_ERROR is returned, an
 *      error message is left in the interp's result.
 *
 * Side effects:
 *      Assume there used to exist a named font by the specified name, and
 *      that the named font had been deleted, but there were still some
 *      widgets using the named font at the time it was deleted.  If a
 *      new named font is created with the same name, all those widgets
 *      that were using the old named font will be redisplayed using
 *      the new named font's attributes.
 *
 *---------------------------------------------------------------------------
 */

static int
CreateNamedFont(interp, tkwin, name, faPtr)
    Tcl_Interp *interp;         /* Interp for error return. */
    Tk_Window tkwin;            /* A window associated with interp. */
    CONST char *name;           /* Name for the new named font. */
    TkFontAttributes *faPtr;    /* Attributes for the new named font. */
{
    TkFontInfo *fiPtr;
    Tcl_HashEntry *namedHashPtr;
    int new;
    NamedFont *nfPtr;    

    fiPtr = ((TkWindow *) tkwin)->mainPtr->fontInfoPtr;

    namedHashPtr = Tcl_CreateHashEntry(&fiPtr->namedTable, name, &new);
                    
    if (new == 0) {
        nfPtr = (NamedFont *) Tcl_GetHashValue(namedHashPtr);
        if (nfPtr->deletePending == 0) {
            Tcl_ResetResult(interp);
            Tcl_AppendResult(interp, "named font \"", name,
                    "\" already exists", (char *) NULL);
            return TCL_ERROR;
        }

        /*
         * Recreating a named font with the same name as a previous
         * named font.  Some widgets were still using that named
         * font, so they need to get redisplayed.
         */

        nfPtr->fa = *faPtr;
        nfPtr->deletePending = 0;
        UpdateDependentFonts(fiPtr, tkwin, namedHashPtr);
        return TCL_OK;
    }

    nfPtr = (NamedFont *) ckalloc(sizeof(NamedFont));
    nfPtr->deletePending = 0;
    Tcl_SetHashValue(namedHashPtr, nfPtr);
    nfPtr->fa = *faPtr;
    nfPtr->refCount = 0;        
    nfPtr->deletePending = 0;
    return TCL_OK;
}

/*
 *---------------------------------------------------------------------------
 *
 * Tk_GetFont -- 
 *
 *      Given a string description of a font, map the description to a
 *      corresponding Tk_Font that represents the font.
 *
 * Results:
 *      The return value is token for the font, or NULL if an error
 *      prevented the font from being created.  If NULL is returned, an
 *      error message will be left in the interp's result.
 *
 * Side effects:
 *      The font is added to an internal database with a reference
 *      count.  For each call to this procedure, there should eventually
 *      be a call to Tk_FreeFont() or Tk_FreeFontFromObj() so that the
 *      database is cleaned up when fonts aren't in use anymore.
 *
 *---------------------------------------------------------------------------
 */

Tk_Font
Tk_GetFont(interp, tkwin, string)
    Tcl_Interp *interp;         /* Interp for database and error return. */
    Tk_Window tkwin;            /* For display on which font will be used. */
    CONST char *string;         /* String describing font, as: named font,
                                 * native format, or parseable string. */
{
    Tk_Font tkfont; 
    Tcl_Obj *strPtr;

    strPtr = Tcl_NewStringObj((char *) string, -1);
    Tcl_IncrRefCount(strPtr);
    tkfont = Tk_AllocFontFromObj(interp, tkwin, strPtr);
    Tcl_DecrRefCount(strPtr);   
    return tkfont;
}

/*
 *---------------------------------------------------------------------------
 *
 * Tk_AllocFontFromObj -- 
 *
 *      Given a string description of a font, map the description to a
 *      corresponding Tk_Font that represents the font.
 *
 * Results:
 *      The return value is token for the font, or NULL if an error
 *      prevented the font from being created.  If NULL is returned, an
 *      error message will be left in interp's result object.
 *
 * Side effects:
 *      The font is added to an internal database with a reference
 *      count.  For each call to this procedure, there should eventually
 *      be a call to Tk_FreeFont() or Tk_FreeFontFromObj() so that the
 *      database is cleaned up when fonts aren't in use anymore.
 *
 *---------------------------------------------------------------------------
 */

Tk_Font
Tk_AllocFontFromObj(interp, tkwin, objPtr)
    Tcl_Interp *interp;         /* Interp for database and error return. */
    Tk_Window tkwin;            /* For screen on which font will be used. */
    Tcl_Obj *objPtr;            /* Object describing font, as: named font,
                                 * native format, or parseable string. */
{
    TkFontInfo *fiPtr;
    Tcl_HashEntry *cacheHashPtr, *namedHashPtr;
    TkFont *fontPtr, *firstFontPtr, *oldFontPtr;
    int new, descent;
    NamedFont *nfPtr;

    fiPtr = ((TkWindow *) tkwin)->mainPtr->fontInfoPtr;
    if (objPtr->typePtr != &fontObjType) {
        SetFontFromAny(interp, objPtr);
    }

    oldFontPtr = (TkFont *) objPtr->internalRep.twoPtrValue.ptr1;

    if (oldFontPtr != NULL) {
        if (oldFontPtr->resourceRefCount == 0) {
            /*
             * This is a stale reference: it refers to a TkFont that's
             * no longer in use.  Clear the reference.
             */

            FreeFontObjProc(objPtr);
            oldFontPtr = NULL;
        } else if (Tk_Screen(tkwin) == oldFontPtr->screen) {
            oldFontPtr->resourceRefCount++;
            return (Tk_Font) oldFontPtr;
        }
    }

    /*
     * Next, search the list of fonts that have the name we want, to see
     * if one of them is for the right screen.
     */

    new = 0;
    if (oldFontPtr != NULL) {
        cacheHashPtr = oldFontPtr->cacheHashPtr;
        FreeFontObjProc(objPtr);
    } else {
        cacheHashPtr = Tcl_CreateHashEntry(&fiPtr->fontCache,
                Tcl_GetString(objPtr), &new);
    }
    firstFontPtr = (TkFont *) Tcl_GetHashValue(cacheHashPtr);
    for (fontPtr = firstFontPtr; (fontPtr != NULL);
            fontPtr = fontPtr->nextPtr) {
        if (Tk_Screen(tkwin) == fontPtr->screen) {
            fontPtr->resourceRefCount++;
            fontPtr->objRefCount++;
            objPtr->internalRep.twoPtrValue.ptr1 = (VOID *) fontPtr;
            return (Tk_Font) fontPtr;
        }
    }

    /*
     * The desired font isn't in the table.  Make a new one.
     */

    namedHashPtr = Tcl_FindHashEntry(&fiPtr->namedTable,
            Tcl_GetString(objPtr));
    if (namedHashPtr != NULL) {
        /*
         * Construct a font based on a named font.
         */

        nfPtr = (NamedFont *) Tcl_GetHashValue(namedHashPtr);
        nfPtr->refCount++;

        fontPtr = TkpGetFontFromAttributes(NULL, tkwin, &nfPtr->fa);
    } else {
        /*
         * Native font?
         */

        fontPtr = TkpGetNativeFont(tkwin, Tcl_GetString(objPtr));
        if (fontPtr == NULL) {
            TkFontAttributes fa;
            Tcl_Obj *dupObjPtr = Tcl_DuplicateObj(objPtr);

            if (ParseFontNameObj(interp, tkwin, dupObjPtr, &fa) != TCL_OK) {
                if (new) {
                    Tcl_DeleteHashEntry(cacheHashPtr);
                }
                Tcl_DecrRefCount(dupObjPtr);
                return NULL;
            }
            Tcl_DecrRefCount(dupObjPtr);

            /*
             * String contained the attributes inline.
             */

            fontPtr = TkpGetFontFromAttributes(NULL, tkwin, &fa);
        }
    }

    fontPtr->resourceRefCount = 1;
    fontPtr->objRefCount = 1;
    fontPtr->cacheHashPtr = cacheHashPtr;
    fontPtr->namedHashPtr = namedHashPtr;
    fontPtr->screen = Tk_Screen(tkwin);
    fontPtr->nextPtr = firstFontPtr;
    Tcl_SetHashValue(cacheHashPtr, fontPtr);

    Tk_MeasureChars((Tk_Font) fontPtr, "0", 1, -1, 0, &fontPtr->tabWidth);
    if (fontPtr->tabWidth == 0) {
        fontPtr->tabWidth = fontPtr->fm.maxWidth;
    }
    fontPtr->tabWidth *= 8;

    /*
     * Make sure the tab width isn't zero (some fonts may not have enough
     * information to set a reasonable tab width).
     */

    if (fontPtr->tabWidth == 0) {
        fontPtr->tabWidth = 1;
    }

    /*
     * Get information used for drawing underlines in generic code on a
     * non-underlined font.
     */
    
    descent = fontPtr->fm.descent;
    fontPtr->underlinePos = descent / 2;
    fontPtr->underlineHeight = TkFontGetPixels(tkwin, fontPtr->fa.size) / 10;
    if (fontPtr->underlineHeight == 0) {
        fontPtr->underlineHeight = 1;
    }
    if (fontPtr->underlinePos + fontPtr->underlineHeight > 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.
         */

        fontPtr->underlineHeight = descent - fontPtr->underlinePos;
        if (fontPtr->underlineHeight == 0) {
            fontPtr->underlinePos--;
            fontPtr->underlineHeight = 1;
        }
    }
    
    objPtr->internalRep.twoPtrValue.ptr1 = (VOID *) fontPtr;
    return (Tk_Font) fontPtr;
}

/*
 *----------------------------------------------------------------------
 *
 * Tk_GetFontFromObj --
 *
 *      Find the font that corresponds to a given object.  The font must
 *      have already been created by Tk_GetFont or Tk_AllocFontFromObj.
 *
 * Results:
 *      The return value is a token for the font that matches objPtr
 *      and is suitable for use in tkwin.
 *
 * Side effects:
 *      If the object is not already a font ref, the conversion will free
 *      any old internal representation. 
 *
 *----------------------------------------------------------------------
 */

Tk_Font
Tk_GetFontFromObj(tkwin, objPtr)
    Tk_Window tkwin;            /* The window that the font will be used in. */
    Tcl_Obj *objPtr;            /* The object from which to get the font. */
{
    TkFontInfo *fiPtr = ((TkWindow *) tkwin)->mainPtr->fontInfoPtr;
    TkFont *fontPtr;
    Tcl_HashEntry *hashPtr;
 
    if (objPtr->typePtr != &fontObjType) {
        SetFontFromAny((Tcl_Interp *) NULL, objPtr);
    }

    fontPtr = (TkFont *) objPtr->internalRep.twoPtrValue.ptr1;

    if (fontPtr != NULL) {
        if (fontPtr->resourceRefCount == 0) {
            /*
             * This is a stale reference: it refers to a TkFont that's
             * no longer in use.  Clear the reference.
             */

            FreeFontObjProc(objPtr);
            fontPtr = NULL;
        } else if (Tk_Screen(tkwin) == fontPtr->screen) {
            return (Tk_Font) fontPtr;
        }
    }

    /*
     * Next, search the list of fonts that have the name we want, to see
     * if one of them is for the right screen.
     */

    if (fontPtr != NULL) {
        hashPtr = fontPtr->cacheHashPtr;
        FreeFontObjProc(objPtr);
    } else {
        hashPtr = Tcl_FindHashEntry(&fiPtr->fontCache, Tcl_GetString(objPtr));
    }
    if (hashPtr != NULL) {
        for (fontPtr = (TkFont *) Tcl_GetHashValue(hashPtr); fontPtr != NULL;
                fontPtr = fontPtr->nextPtr) {
            if (Tk_Screen(tkwin) == fontPtr->screen) {
                fontPtr->objRefCount++;
                objPtr->internalRep.twoPtrValue.ptr1 = (VOID *) fontPtr;
                return (Tk_Font) fontPtr;
            }
        }
    }

    panic("Tk_GetFontFromObj called with non-existent font!");
    return NULL;
}

/*
 *----------------------------------------------------------------------
 *
 * SetFontFromAny --
 *
 *      Convert the internal representation of a Tcl object to the
 *      font internal form.
 *
 * Results:
 *      Always returns TCL_OK.
 *
 * Side effects:
 *      The object is left with its typePtr pointing to fontObjType.
 *      The TkFont pointer is NULL.
 *
 *----------------------------------------------------------------------
 */

static int
SetFontFromAny(interp, objPtr)
    Tcl_Interp *interp;         /* Used for error reporting if not NULL. */
    Tcl_Obj *objPtr;            /* The object to convert. */
{
    Tcl_ObjType *typePtr;

    /*
     * Free the old internalRep before setting the new one. 
     */

    Tcl_GetString(objPtr);
    typePtr = objPtr->typePtr;
    if ((typePtr != NULL) && (typePtr->freeIntRepProc != NULL)) {
        (*typePtr->freeIntRepProc)(objPtr);
    }
    objPtr->typePtr = &fontObjType;
    objPtr->internalRep.twoPtrValue.ptr1 = NULL;

    return TCL_OK;
}

/*
 *---------------------------------------------------------------------------
 *
 * Tk_NameOfFont --
 *
 *      Given a font, return a textual string identifying it.
 *
 * Results:
 *      The return value is the description that was passed to
 *      Tk_GetFont() to create the font.  The storage for the returned
 *      string is only guaranteed to persist until the font is deleted.
 *      The caller should not modify this string.
 *
 * Side effects:
 *      None.
 *
 *---------------------------------------------------------------------------
 */

char *
Tk_NameOfFont(tkfont)
    Tk_Font tkfont;             /* Font whose name is desired. */
{
    TkFont *fontPtr;

    fontPtr = (TkFont *) tkfont;
    return fontPtr->cacheHashPtr->key.string;
}

/*
 *---------------------------------------------------------------------------
 *
 * Tk_FreeFont -- 
 *
 *      Called to release a font allocated by Tk_GetFont().
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The reference count associated with font is decremented, and
 *      only deallocated when no one is using it.
 *
 *---------------------------------------------------------------------------
 */

void
Tk_FreeFont(tkfont)
    Tk_Font tkfont;             /* Font to be released. */
{
    TkFont *fontPtr, *prevPtr;
    NamedFont *nfPtr;

    if (tkfont == NULL) {
        return;
    }
    fontPtr = (TkFont *) tkfont;
    fontPtr->resourceRefCount--;
    if (fontPtr->resourceRefCount > 0) {
        return;
    }
    if (fontPtr->namedHashPtr != NULL) {
        /*
         * This font derived from a named font.  Reduce the reference
         * count on the named font and free it if no-one else is
         * using it.
         */

        nfPtr = (NamedFont *) Tcl_GetHashValue(fontPtr->namedHashPtr);
        nfPtr->refCount--;
        if ((nfPtr->refCount == 0) && (nfPtr->deletePending != 0)) {
            Tcl_DeleteHashEntry(fontPtr->namedHashPtr);
            ckfree((char *) nfPtr);
        }
    }

    prevPtr = (TkFont *) Tcl_GetHashValue(fontPtr->cacheHashPtr);
    if (prevPtr == fontPtr) {
        if (fontPtr->nextPtr == NULL) {
            Tcl_DeleteHashEntry(fontPtr->cacheHashPtr);
        } else  {
            Tcl_SetHashValue(fontPtr->cacheHashPtr, fontPtr->nextPtr);
        }
    } else {
        while (prevPtr->nextPtr != fontPtr) {
            prevPtr = prevPtr->nextPtr;
        }
        prevPtr->nextPtr = fontPtr->nextPtr;
    }

    TkpDeleteFont(fontPtr);
    if (fontPtr->objRefCount == 0) {
        ckfree((char *) fontPtr);
    }
}

/*
 *---------------------------------------------------------------------------
 *
 * Tk_FreeFontFromObj -- 
 *
 *      Called to release a font inside a Tcl_Obj *. Decrements the refCount
 *      of the font and removes it from the hash tables if necessary.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The reference count associated with font is decremented, and
 *      only deallocated when no one is using it.
 *
 *---------------------------------------------------------------------------
 */

void
Tk_FreeFontFromObj(tkwin, objPtr)
    Tk_Window tkwin;            /* The window this font lives in. Needed
                                 * for the screen value. */
    Tcl_Obj *objPtr;            /* The Tcl_Obj * to be freed. */
{
    Tk_FreeFont(Tk_GetFontFromObj(tkwin, objPtr));
}

/*
 *---------------------------------------------------------------------------
 *
 * FreeFontObjProc -- 
 *
 *      This proc is called to release an object reference to a font.
 *      Called when the object's internal rep is released or when
 *      the cached fontPtr needs to be changed.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The object reference count is decremented. When both it
 *      and the hash ref count go to zero, the font's resources
 *      are released.
 *
 *---------------------------------------------------------------------------
 */

static void
FreeFontObjProc(objPtr)
    Tcl_Obj *objPtr;            /* The object we are releasing. */
{
    TkFont *fontPtr = (TkFont *) objPtr->internalRep.twoPtrValue.ptr1;

    if (fontPtr != NULL) {
        fontPtr->objRefCount--;
        if ((fontPtr->resourceRefCount == 0) && (fontPtr->objRefCount == 0)) {
            ckfree((char *) fontPtr);
            objPtr->internalRep.twoPtrValue.ptr1 = NULL;
        }
    }
}

/*
 *---------------------------------------------------------------------------
 *
 * DupFontObjProc -- 
 *
 *      When a cached font object is duplicated, this is called to
 *      update the internal reps.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The font's objRefCount is incremented and the internal rep
 *      of the copy is set to point to it.
 *
 *---------------------------------------------------------------------------
 */

static void
DupFontObjProc(srcObjPtr, dupObjPtr)
    Tcl_Obj *srcObjPtr;         /* The object we are copying from. */
    Tcl_Obj *dupObjPtr;         /* The object we are copying to. */
{
    TkFont *fontPtr = (TkFont *) srcObjPtr->internalRep.twoPtrValue.ptr1;
    
    dupObjPtr->typePtr = srcObjPtr->typePtr;
    dupObjPtr->internalRep.twoPtrValue.ptr1 = (VOID *) fontPtr;

    if (fontPtr != NULL) {
        fontPtr->objRefCount++;
    }
}

/*
 *---------------------------------------------------------------------------
 *
 * Tk_FontId --
 *
 *      Given a font, return an opaque handle that should be selected
 *      into the XGCValues structure in order to get the constructed
 *      gc to use this font.  This procedure would go away if the
 *      XGCValues structure were replaced with a TkGCValues structure.
 *
 * Results:
 *      As above.
 *
 * Side effects:
 *      None.
 *
 *---------------------------------------------------------------------------
 */

Font
Tk_FontId(tkfont)
    Tk_Font tkfont;     /* Font that is going to be selected into GC. */
{
    TkFont *fontPtr;

    fontPtr = (TkFont *) tkfont;
    return fontPtr->fid;
}

/*
 *---------------------------------------------------------------------------
 *
 * Tk_GetFontMetrics --
 *
 *      Returns overall ascent and descent metrics for the given font.
 *      These values can be used to space multiple lines of text and
 *      to align the baselines of text in different fonts.
 *
 * Results:
 *      If *heightPtr is non-NULL, it is filled with the overall height
 *      of the font, which is the sum of the ascent and descent.
 *      If *ascentPtr or *descentPtr is non-NULL, they are filled with
 *      the ascent and/or descent information for the font.
 *
 * Side effects:
 *      None.
 *
 *---------------------------------------------------------------------------
 */
void
Tk_GetFontMetrics(tkfont, fmPtr)
    Tk_Font tkfont;             /* Font in which metrics are calculated. */
    Tk_FontMetrics *fmPtr;      /* Pointer to structure in which font
                                 * metrics for tkfont will be stored. */
{
    TkFont *fontPtr;

    fontPtr = (TkFont *) tkfont;
    fmPtr->ascent = fontPtr->fm.ascent;
    fmPtr->descent = fontPtr->fm.descent;
    fmPtr->linespace = fontPtr->fm.ascent + fontPtr->fm.descent;
}

/*
 *---------------------------------------------------------------------------
 *
 * Tk_PostscriptFontName --
 *
 *      Given a Tk_Font, return the name of the corresponding Postscript
 *      font.
 *
 * Results:
 *      The return value is the pointsize of the given Tk_Font.
 *      The name of the Postscript font is appended to dsPtr.
 *
 * Side effects:
 *      If the font does not exist on the printer, the print job will
 *      fail at print time.  Given a "reasonable" Postscript printer,
 *      the following Tk_Font 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 Tk_Font font families may not print correctly
 *      because the computed Postscript font name may be incorrect.
 *
 *---------------------------------------------------------------------------
 */

int
Tk_PostscriptFontName(tkfont, dsPtr)
    Tk_Font tkfont;             /* Font in which text will be printed. */
    Tcl_DString *dsPtr;         /* Pointer to an initialized Tcl_DString to
                                 * which the name of the Postscript font that
                                 * corresponds to tkfont will be appended. */
{
    TkFont *fontPtr;
    char *family, *weightString, *slantString;
    char *src, *dest;
    int upper, len;

    len = Tcl_DStringLength(dsPtr);
    fontPtr = (TkFont *) tkfont;

    /*
     * Convert the case-insensitive Tk_Font family name to the
     * case-sensitive Postscript family name.  Take out any spaces and
     * capitalize the first letter of each word.
     */

    family = fontPtr->fa.family;
    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 {
        Tcl_UniChar ch;

        /*
         * 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 DString shorter, which is
         * safe to do.
         */

        Tcl_DStringAppend(dsPtr, family, -1);

        src = dest = Tcl_DStringValue(dsPtr) + len;
        upper = 1;
        for (; *src != '\0'; ) {
            while (isspace(UCHAR(*src))) { /* INTL: ISO space */
                src++;
                upper = 1;
            }
            src += Tcl_UtfToUniChar(src, &ch);
            if (upper) {
                ch = Tcl_UniCharToUpper(ch);
                upper = 0;
            } else {
                ch = Tcl_UniCharToLower(ch);
            }
            dest += Tcl_UniCharToUtf(ch, dest);
        }
        *dest = '\0';
        Tcl_DStringSetLength(dsPtr, dest - Tcl_DStringValue(dsPtr));
        family = Tcl_DStringValue(dsPtr) + len;
    }
    if (family != Tcl_DStringValue(dsPtr) + len) {
        Tcl_DStringAppend(dsPtr, family, -1);
        family = Tcl_DStringValue(dsPtr) + len;
    }

    if (strcasecmp(family, "NewCenturySchoolbook") == 0) {
        Tcl_DStringSetLength(dsPtr, len);
        Tcl_DStringAppend(dsPtr, "NewCenturySchlbk", -1);
        family = Tcl_DStringValue(dsPtr) + len;
    }

    /*
     * Get the string to use for the weight.
     */

    weightString = NULL;
    if (fontPtr->fa.weight == TK_FW_NORMAL) {
        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 = NULL;
    if (fontPtr->fa.slant == TK_FS_ROMAN) {
        ;
    } 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 == NULL) && (weightString == NULL)) {
        if ((strcmp(family, "Times") == 0) 
                || (strcmp(family, "NewCenturySchlbk") == 0)
                || (strcmp(family, "Palatino") == 0)) {
            Tcl_DStringAppend(dsPtr, "-Roman", -1);
        }
    } else {
        Tcl_DStringAppend(dsPtr, "-", -1);
        if (weightString != NULL) {
            Tcl_DStringAppend(dsPtr, weightString, -1);
        }
        if (slantString != NULL) {
            Tcl_DStringAppend(dsPtr, slantString, -1);
        }
    }

    return fontPtr->fa.size;
}

/*
 *---------------------------------------------------------------------------
 *
 * Tk_TextWidth --
 *
 *      A wrapper function for the more complicated interface of
 *      Tk_MeasureChars.  Computes how much space the given
 *      simple string needs.
 *
 * Results:
 *      The return value is the width (in pixels) of the given string.
 *
 * Side effects:
 *      None.
 *
 *---------------------------------------------------------------------------
 */

int
Tk_TextWidth(tkfont, string, numBytes)
    Tk_Font tkfont;             /* Font in which text will be measured. */
    CONST char *string;         /* String whose width will be computed. */
    int numBytes;               /* Number of bytes to consider from
                                 * string, or < 0 for strlen(). */
{
    int width;

    if (numBytes < 0) {
        numBytes = strlen(string);
    }
    Tk_MeasureChars(tkfont, string, numBytes, -1, 0, &width);
    return width;
}

/*
 *---------------------------------------------------------------------------
 *
 * Tk_UnderlineChars --
 *
 *      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. 
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      Information gets displayed in "drawable".
 *
 *----------------------------------------------------------------------
 */

void
Tk_UnderlineChars(display, drawable, gc, tkfont, string, x, y, firstByte,
        lastByte)
    Display *display;           /* Display on which to draw. */
    Drawable drawable;          /* Window or pixmap in which to draw. */
    GC gc;                      /* Graphics context for actually drawing
                                 * line. */
    Tk_Font tkfont;             /* Font used in GC;  must have been allocated
                                 * by Tk_GetFont().  Used for character
                                 * dimensions, etc. */
    CONST char *string;         /* String containing characters to be
                                 * underlined or overstruck. */
    int x, y;                   /* Coordinates at which first character of
                                 * string is drawn. */
    int firstByte;              /* Index of first byte of first character. */
    int lastByte;               /* Index of first byte after the last
                                 * character. */
{
    TkFont *fontPtr;
    int startX, endX;

    fontPtr = (TkFont *) tkfont;
    
    Tk_MeasureChars(tkfont, string, firstByte, -1, 0, &startX);
    Tk_MeasureChars(tkfont, string, lastByte, -1, 0, &endX);

    XFillRectangle(display, drawable, gc, x + startX,
            y + fontPtr->underlinePos, (unsigned int) (endX - startX),
            (unsigned int) fontPtr->underlineHeight);
}

/*
 *---------------------------------------------------------------------------
 *
 * Tk_ComputeTextLayout --
 *
 *      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 Tk_DrawTextLayout() 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 Tk to handle the
 *      details.
 *
 * Results:
 *      The return value is a Tk_TextLayout 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 freed.  To free
 *      the token, call Tk_FreeTextLayout().
 *
 *      The dimensions of the screen area needed to display the text
 *      are stored in *widthPtr and *heightPtr.
 *
 * Side effects:
 *      Memory is allocated to hold the measurement information.  
 *
 *---------------------------------------------------------------------------
 */

Tk_TextLayout
Tk_ComputeTextLayout(tkfont, string, numChars, wrapLength, justify, flags,
        widthPtr, heightPtr)
    Tk_Font tkfont;             /* Font that will be used to display text. */
    CONST char *string;         /* String whose dimensions are to be
                                 * computed. */
    int numChars;               /* Number of characters to consider from
                                 * string, or < 0 for strlen(). */
    int wrapLength;             /* Longest permissible line length, in
                                 * pixels.  <= 0 means no automatic wrapping:
                                 * just let lines get as long as needed. */
    Tk_Justify justify;         /* How to justify lines. */
    int flags;                  /* Flag bits OR-ed together.
                                 * TK_IGNORE_TABS means that tab characters
                                 * should not be expanded.  TK_IGNORE_NEWLINES
                                 * means that newline characters should not
                                 * cause a line break. */
    int *widthPtr;              /* Filled with width of string. */
    int *heightPtr;             /* Filled with height of string. */
{
    TkFont *fontPtr;
    CONST char *start, *end, *special;
    int n, y, bytesThisChunk, maxChunks;
    int baseline, height, curX, newX, maxWidth;
    TextLayout *layoutPtr;
    LayoutChunk *chunkPtr;
    CONST TkFontMetrics *fmPtr;
    Tcl_DString lineBuffer;
    int *lineLengths;
    int curLine, layoutHeight;

    Tcl_DStringInit(&lineBuffer);
    
    fontPtr = (TkFont *) tkfont;
    if ((fontPtr == NULL) || (string == NULL)) {
        if (widthPtr != NULL) {
            *widthPtr = 0;
        }
        if (heightPtr != NULL) {
            *heightPtr = 0;
        }
        return NULL;
    }

    fmPtr = &fontPtr->fm;

    height = fmPtr->ascent + fmPtr->descent;

    if (numChars < 0) {
        numChars = Tcl_NumUtfChars(string, -1);
    }
    if (wrapLength == 0) {
        wrapLength = -1;
    }

    maxChunks = 1;

    layoutPtr = (TextLayout *) ckalloc(sizeof(TextLayout)
            + (maxChunks - 1) * sizeof(LayoutChunk));
    layoutPtr->tkfont       = tkfont;
    layoutPtr->string       = string;
    layoutPtr->numChunks    = 0;

    baseline = fmPtr->ascent;
    maxWidth = 0;

    /*
     * Divide the string up into simple strings and measure each string.
     */

    curX = 0;

    end = Tcl_UtfAtIndex(string, numChars);
    special = string;

    flags &= TK_IGNORE_TABS | TK_IGNORE_NEWLINES;
    flags |= TK_WHOLE_WORDS | TK_AT_LEAST_ONE;      
    for (start = string; start < end; ) {
        if (start >= special) {
            /*
             * Find the next special character in the string.
             *
             * INTL: Note that it is safe to increment by byte, because we are
             * looking for 7-bit characters that will appear unchanged in
             * UTF-8.  At some point we may need to support the full Unicode
             * whitespace set.
             */

            for (special = start; special < end; special++) {
                if (!(flags & TK_IGNORE_NEWLINES)) {
                    if ((*special == '\n') || (*special == '\r')) {
                        break;
                    }
                }
                if (!(flags & TK_IGNORE_TABS)) {
                    if (*special == '\t') {
                        break;
                    }
                }
            }
        }

        /*
         * Special points at the next special character (or the end of the
         * string).  Process characters between start and special.
         */

        chunkPtr = NULL;
        if (start < special) {
            bytesThisChunk = Tk_MeasureChars(tkfont, start, special - start,
                    wrapLength - curX, flags, &newX);
            newX += curX;
            flags &= ~TK_AT_LEAST_ONE;
            if (bytesThisChunk > 0) {
                chunkPtr = NewChunk(&layoutPtr, &maxChunks, start,
                        bytesThisChunk, curX, newX, baseline);
                        
                start += bytesThisChunk;
                curX = newX;
            }
        }

        if ((start == special) && (special < end)) {
            /*
             * Handle the special character.
             *
             * INTL: Special will be pointing at a 7-bit character so we
             * can safely treat it as a single byte.
             */

            chunkPtr = NULL;
            if (*special == '\t') {
                newX = curX + fontPtr->tabWidth;
                newX -= newX % fontPtr->tabWidth;
                NewChunk(&layoutPtr, &maxChunks, start, 1, curX, newX,
                        baseline)->numDisplayChars = -1;
                start++;
                if ((start < end) &&
                        ((wrapLength <= 0) || (newX <= wrapLength))) {
                    /*
                     * More chars can still fit on this line.
                     */

                    curX = newX;
                    flags &= ~TK_AT_LEAST_ONE;
                    continue;
                }
            } else {    
                NewChunk(&layoutPtr, &maxChunks, start, 1, curX, curX,
                        baseline)->numDisplayChars = -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(*start))) { /* INTL: ISO space */
            if (!(flags & TK_IGNORE_NEWLINES)) {
                if ((*start == '\n') || (*start == '\r')) {
                    break;
                }
            }
            if (!(flags & TK_IGNORE_TABS)) {
                if (*start == '\t') {
                    break;
                }
            }
            start++;
        }
        if (chunkPtr != NULL) {
            CONST char *end;

            /*
             * Append all the extra spaces on this line to the end of the
             * last text chunk.  This is a little tricky because we are
             * switching back and forth between characters and bytes.
             */

            end = chunkPtr->start + chunkPtr->numBytes;
            bytesThisChunk = start - end;
            if (bytesThisChunk > 0) {
                bytesThisChunk = Tk_MeasureChars(tkfont, end, bytesThisChunk,
                        -1, 0, &chunkPtr->totalWidth);
                chunkPtr->numBytes += bytesThisChunk;
                chunkPtr->numChars += Tcl_NumUtfChars(end, bytesThisChunk);
                chunkPtr->totalWidth += curX;
            }
        }

        wrapLine: 
        flags |= TK_AT_LEAST_ONE;

        /*
         * 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.
         */

        Tcl_DStringAppend(&lineBuffer, (char *) &curX, sizeof(curX));

        curX = 0;
        baseline += height;
    }

    /*
     * 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 ((layoutPtr->numChunks > 0) && ((flags & TK_IGNORE_NEWLINES) == 0)) {
        if (layoutPtr->chunks[layoutPtr->numChunks - 1].start[0] == '\n') {
            chunkPtr = NewChunk(&layoutPtr, &maxChunks, start, 0, curX,
                    curX, baseline);
            chunkPtr->numDisplayChars = -1;
            Tcl_DStringAppend(&lineBuffer, (char *) &curX, sizeof(curX));
            baseline += height;
        }
    }       

    layoutPtr->width = maxWidth;
    layoutHeight = baseline - fmPtr->ascent;
    if (layoutPtr->numChunks == 0) {
        layoutHeight = height;

        /*
         * 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.
         */

        layoutPtr->numChunks = 1;
        layoutPtr->chunks[0].start              = string;
        layoutPtr->chunks[0].numBytes           = 0;
        layoutPtr->chunks[0].numChars           = 0;
        layoutPtr->chunks[0].numDisplayChars    = -1;
        layoutPtr->chunks[0].x                  = 0;
        layoutPtr->chunks[0].y                  = fmPtr->ascent;
        layoutPtr->chunks[0].totalWidth         = 0;
        layoutPtr->chunks[0].displayWidth       = 0;
    } else {
        /*
         * Using maximum line length, shift all the chunks so that the lines
         * are all justified correctly.
         */
    
        curLine = 0;
        chunkPtr = layoutPtr->chunks;
        y = chunkPtr->y;
        lineLengths = (int *) Tcl_DStringValue(&lineBuffer);
        for (n = 0; n < layoutPtr->numChunks; n++) {
            int extra;

            if (chunkPtr->y != y) {
                curLine++;
                y = chunkPtr->y;
            }
            extra = maxWidth - lineLengths[curLine];
            if (justify == TK_JUSTIFY_CENTER) {
                chunkPtr->x += extra / 2;
            } else if (justify == TK_JUSTIFY_RIGHT) {
                chunkPtr->x += extra;
            }
            chunkPtr++;
        }
    }

    if (widthPtr != NULL) {
        *widthPtr = layoutPtr->width;
    }
    if (heightPtr != NULL) {
        *heightPtr = layoutHeight;
    }
    Tcl_DStringFree(&lineBuffer);

    return (Tk_TextLayout) layoutPtr;
}

/*
 *---------------------------------------------------------------------------
 *
 * Tk_FreeTextLayout --
 *
 *      This procedure is called to release the storage associated with
 *      a Tk_TextLayout when it is no longer needed.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      Memory is freed.
 *
 *---------------------------------------------------------------------------
 */

void
Tk_FreeTextLayout(textLayout)
    Tk_TextLayout textLayout;   /* The text layout to be released. */
{
    TextLayout *layoutPtr;

    layoutPtr = (TextLayout *) textLayout;
    if (layoutPtr != NULL) {
        ckfree((char *) layoutPtr);
    }
}

/*
 *---------------------------------------------------------------------------
 *
 * Tk_DrawTextLayout --
 *
 *      Use the information in the Tk_TextLayout token 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 Tk to handle
 *      the details.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      Text drawn on the screen.
 *
 *---------------------------------------------------------------------------
 */

void
Tk_DrawTextLayout(display, drawable, gc, layout, x, y, firstChar, lastChar)
    Display *display;           /* Display on which to draw. */
    Drawable drawable;          /* Window or pixmap in which to draw. */
    GC gc;                      /* Graphics context to use for drawing text. */
    Tk_TextLayout layout;       /* Layout information, from a previous call
                                 * to Tk_ComputeTextLayout(). */
    int x, y;                   /* Upper-left hand corner of rectangle in
                                 * which to draw (pixels). */
    int firstChar;              /* The index of the first character to draw
                                 * from the given text item.  0 specfies the
                                 * beginning. */
    int lastChar;               /* The index just after the last character
                                 * to draw from the given text item.  A number
                                 * < 0 means to draw all characters. */
{
    TextLayout *layoutPtr;
    int i, numDisplayChars, drawX;
    CONST char *firstByte;
    CONST char *lastByte;
    LayoutChunk *chunkPtr;

    layoutPtr = (TextLayout *) layout;
    if (layoutPtr == NULL) {
        return;
    }

    if (lastChar < 0) {
        lastChar = 100000000;
    }
    chunkPtr = layoutPtr->chunks;
    for (i = 0; i < layoutPtr->numChunks; i++) {
        numDisplayChars = chunkPtr->numDisplayChars;
        if ((numDisplayChars > 0) && (firstChar < numDisplayChars)) {
            if (firstChar <= 0) {
                drawX = 0;
                firstChar = 0;
                firstByte = chunkPtr->start;
            } else {
                firstByte = Tcl_UtfAtIndex(chunkPtr->start, firstChar);
                Tk_MeasureChars(layoutPtr->tkfont, chunkPtr->start,
                        firstByte - chunkPtr->start, -1, 0, &drawX);
            }
            if (lastChar < numDisplayChars) {
                numDisplayChars = lastChar;
            }
            lastByte = Tcl_UtfAtIndex(chunkPtr->start, numDisplayChars);
            Tk_DrawChars(display, drawable, gc, layoutPtr->tkfont,
                    firstByte, lastByte - firstByte,
                    x + chunkPtr->x + drawX, y + chunkPtr->y);
        }
        firstChar -= chunkPtr->numChars;
        lastChar -= chunkPtr->numChars;
        if (lastChar <= 0) {
            break;
        }
        chunkPtr++;
    }
}

/*
 *---------------------------------------------------------------------------
 *
 * Tk_UnderlineTextLayout --
 *
 *      Use the information in the Tk_TextLayout token 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 Tk to handle the details.
 *      To display larger amounts of underlined text, construct
 *      and use an underlined font.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      Underline drawn on the screen.
 *
 *---------------------------------------------------------------------------
 */

void
Tk_UnderlineTextLayout(display, drawable, gc, layout, x, y, underline)
    Display *display;           /* Display on which to draw. */
    Drawable drawable;          /* Window or pixmap in which to draw. */
    GC gc;                      /* Graphics context to use for drawing text. */
    Tk_TextLayout layout;       /* Layout information, from a previous call
                                 * to Tk_ComputeTextLayout(). */
    int x, y;                   /* Upper-left hand corner of rectangle in
                                 * which to draw (pixels). */
    int underline;              /* Index of the single character to
                                 * underline, or -1 for no underline. */
{
    TextLayout *layoutPtr;
    TkFont *fontPtr;
    int xx, yy, width, height;

    if ((Tk_CharBbox(layout, underline, &xx, &yy, &width, &height) != 0)
            && (width != 0)) {
        layoutPtr = (TextLayout *) layout;
        fontPtr = (TkFont *) layoutPtr->tkfont;

        XFillRectangle(display, drawable, gc, x + xx, 
                y + yy + fontPtr->fm.ascent + fontPtr->underlinePos,
                (unsigned int) width, (unsigned int) fontPtr->underlineHeight);
    }
}

/*
 *---------------------------------------------------------------------------
 *
 * Tk_PointToChar --
 *
 *      Use the information in the Tk_TextLayout 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.
 *
 * Results:
 *      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.
 *
 * Side effects:
 *      None.
 *
 *---------------------------------------------------------------------------
 */

int
Tk_PointToChar(layout, x, y)
    Tk_TextLayout layout;       /* Layout information, from a previous call
                                 * to Tk_ComputeTextLayout(). */
    int x, y;                   /* Coordinates of point to check, with
                                 * respect to the upper-left corner of the
                                 * text layout. */
{
    TextLayout *layoutPtr;
    LayoutChunk *chunkPtr, *lastPtr;
    TkFont *fontPtr;
    int i, n, dummy, baseline, pos, numChars;

    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.
     */

    layoutPtr = (TextLayout *) layout;
    fontPtr = (TkFont *) layoutPtr->tkfont;
    lastPtr = chunkPtr = layoutPtr->chunks;
    numChars = 0;
    for (i = 0; i < layoutPtr->numChunks; i++) {
        baseline = chunkPtr->y;
        if (y < baseline + fontPtr->fm.descent) {
            if (x < chunkPtr->x) {
                /*
                 * Point is to the left of all chunks on this line.  Return
                 * the index of the first character on this line.
                 */

                return numChars;
            }
            if (x >= layoutPtr->width) {
                /*
                 * 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.
             */

            lastPtr = chunkPtr;
            while ((i < layoutPtr->numChunks) && (chunkPtr->y == baseline))  {
                if (x < chunkPtr->x + chunkPtr->totalWidth) {
                    /*
                     * Point falls on one of the characters in this chunk.
                     */

                    if (chunkPtr->numDisplayChars < 0) {
                        /*
                         * This is a special chunk that encapsulates a single
                         * tab or newline char.
                         */

                        return numChars;
                    }
                    n = Tk_MeasureChars((Tk_Font) fontPtr, chunkPtr->start,
                            chunkPtr->numBytes, x - chunkPtr->x,
                            0, &dummy);
                    return numChars + Tcl_NumUtfChars(chunkPtr->start, n);
                }
                numChars += chunkPtr->numChars;
                lastPtr = chunkPtr;
                chunkPtr++;
                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 = numChars;
            if (i < layoutPtr->numChunks) {
                pos--;
            }
            return pos;
        }
        numChars += chunkPtr->numChars;
        lastPtr = chunkPtr;
        chunkPtr++;
    }

    /*
     * Point lies below any line in this text layout.  Return the index
     * just past the last char.
     */

    return (lastPtr->start + lastPtr->numChars) - layoutPtr->string;
}

/*
 *---------------------------------------------------------------------------
 *
 * Tk_CharBbox --
 *
 *      Use the information in the Tk_TextLayout 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.
 * 
 * Results:
 *      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.
 *
 * Side effects:
 *      None.
 *
 *---------------------------------------------------------------------------
 */

int
Tk_CharBbox(layout, index, xPtr, yPtr, widthPtr, heightPtr)
    Tk_TextLayout layout;   /* Layout information, from a previous call to
                             * Tk_ComputeTextLayout(). */
    int index;              /* The index of the character whose bbox is
                             * desired. */
    int *xPtr, *yPtr;       /* Filled with the upper-left hand corner, in
                             * pixels, of the bounding box for the character
                             * specified by index, if non-NULL. */
    int *widthPtr, *heightPtr;
                            /* Filled with the width and height of the
                             * bounding box for the character specified by
                             * index, if non-NULL. */
{
    TextLayout *layoutPtr;
    LayoutChunk *chunkPtr;
    int i, x, w;
    Tk_Font tkfont;
    TkFont *fontPtr;
    CONST char *end;

    if (index < 0) {
        return 0;
    }

    layoutPtr = (TextLayout *) layout;
    chunkPtr = layoutPtr->chunks;
    tkfont = layoutPtr->tkfont;
    fontPtr = (TkFont *) tkfont;

    for (i = 0; i < layoutPtr->numChunks; i++) {
        if (chunkPtr->numDisplayChars < 0) {
            if (index == 0) {
                x = chunkPtr->x;
                w = chunkPtr->totalWidth;
                goto check;
            }
        } else if (index < chunkPtr->numChars) {
            end = Tcl_UtfAtIndex(chunkPtr->start, index);
            if (xPtr != NULL) {
                Tk_MeasureChars(tkfont, chunkPtr->start,
                        end -  chunkPtr->start, -1, 0, &x);
                x += chunkPtr->x;
            }
            if (widthPtr != NULL) {
                Tk_MeasureChars(tkfont, end, Tcl_UtfNext(end) - end,
                        -1, 0, &w);
            }
            goto check;
        }
        index -= chunkPtr->numChars;
        chunkPtr++;
    }
    if (index == 0) {
        /*
         * Special case to get location just past last char in layout.
         */

        chunkPtr--;
        x = chunkPtr->x + chunkPtr->totalWidth;
        w = 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 (yPtr != NULL) {
        *yPtr = chunkPtr->y - fontPtr->fm.ascent;
    }
    if (heightPtr != NULL) {
        *heightPtr = fontPtr->fm.ascent + fontPtr->fm.descent;
    }

    if (x > layoutPtr->width) {
        x = layoutPtr->width;
    }
    if (xPtr != NULL) {
        *xPtr = x;
    }
    if (widthPtr != NULL) {
        if (x + w > layoutPtr->width) {
            w = layoutPtr->width - x;
        }
        *widthPtr = w;
    }

    return 1;
}

/*
 *---------------------------------------------------------------------------
 *
 * Tk_DistanceToTextLayout --
 *
 *      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.
 *
 * Results:
 *      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.
 *
 * Side effects:
 *      None.
 *
 *---------------------------------------------------------------------------
 */

int
Tk_DistanceToTextLayout(layout, x, y)
    Tk_TextLayout layout;       /* Layout information, from a previous call
                                 * to Tk_ComputeTextLayout(). */
    int x, y;                   /* Coordinates of point to check, with
                                 * respect to the upper-left corner of the
                                 * text layout (in pixels). */
{
    int i, x1, x2, y1, y2, xDiff, yDiff, dist, minDist, ascent, descent;
    LayoutChunk *chunkPtr;
    TextLayout *layoutPtr;
    TkFont *fontPtr;

    layoutPtr = (TextLayout *) layout;
    fontPtr = (TkFont *) layoutPtr->tkfont;
    ascent = fontPtr->fm.ascent;
    descent = fontPtr->fm.descent;
    
    minDist = 0;
    chunkPtr = layoutPtr->chunks;
    for (i = 0; i < layoutPtr->numChunks; i++) {
        if (chunkPtr->start[0] == '\n') {
            /*
             * Newline characters are not counted when computing distance
             * (but tab characters would still be considered).
             */

            chunkPtr++;
            continue;
        }

        x1 = chunkPtr->x;
        y1 = chunkPtr->y - ascent;
        x2 = chunkPtr->x + chunkPtr->displayWidth;
        y2 = chunkPtr->y + 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) hypot((double) xDiff, (double) yDiff);
        if ((dist < minDist) || (minDist == 0)) {
            minDist = dist;
        }
        chunkPtr++;
    }
    return minDist;
}

/*
 *---------------------------------------------------------------------------
 *
 * Tk_IntersectTextLayout --
 *
 *      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.
 *
 * Results:
 *      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.
 *
 * Side effects:
 *      None.
 *
 *---------------------------------------------------------------------------
 */

int
Tk_IntersectTextLayout(layout, x, y, width, height)
    Tk_TextLayout layout;       /* Layout information, from a previous call
                                 * to Tk_ComputeTextLayout(). */
    int 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. */
    int width, height;          /* The width and height of the above
                                 * rectangular area, in pixels. */
{
    int result, i, x1, y1, x2, y2;
    TextLayout *layoutPtr;
    LayoutChunk *chunkPtr;
    TkFont *fontPtr;
    int 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.
     */
    
    layoutPtr = (TextLayout *) layout;
    chunkPtr = layoutPtr->chunks;
    fontPtr = (TkFont *) layoutPtr->tkfont;

    left    = x;
    top     = y;
    right   = x + width;
    bottom  = y + height;

    result = 0;
    for (i = 0; i < layoutPtr->numChunks; i++) {
        if (chunkPtr->start[0] == '\n') {
            /*
             * Newline characters are not counted when computing area
             * intersection (but tab characters would still be considered).
             */

            chunkPtr++;
            continue;
        }

        x1 = chunkPtr->x;
        y1 = chunkPtr->y - fontPtr->fm.ascent;
        x2 = chunkPtr->x + chunkPtr->displayWidth;
        y2 = chunkPtr->y + fontPtr->fm.descent;

        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;
        }
        chunkPtr++;
    }
    return result;
}

/*
 *---------------------------------------------------------------------------
 *
 * Tk_TextLayoutToPostscript --
 *
 *      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.
 *
 * Results:
 *      The interp's result is modified to hold the Postscript code that
 *      will render the text layout.
 *
 * Side effects:
 *      None.
 *
 *---------------------------------------------------------------------------
 */

void
Tk_TextLayoutToPostscript(interp, layout)
    Tcl_Interp *interp;         /* Filled with Postscript code. */
    Tk_TextLayout layout;       /* The layout to be rendered. */
{
#define MAXUSE 128
    char buf[MAXUSE+10];
    LayoutChunk *chunkPtr;
    int i, j, used, c, baseline;
    Tcl_UniChar ch;
    CONST char *p;
    TextLayout *layoutPtr;

    layoutPtr = (TextLayout *) layout;
    chunkPtr = layoutPtr->chunks;
    baseline = chunkPtr->y;
    used = 0;
    buf[used++] = '(';
    for (i = 0; i < layoutPtr->numChunks; i++) {
        if (baseline != chunkPtr->y) {
            buf[used++] = ')';
            buf[used++] = '\n';
            buf[used++] = '(';
            baseline = chunkPtr->y;
        }
        if (chunkPtr->numDisplayChars <= 0) {
            if (chunkPtr->start[0] == '\t') {
                buf[used++] = '\\';
                buf[used++] = 't';
            }
        } else {
            p = chunkPtr->start;
            for (j = 0; j < chunkPtr->numDisplayChars; j++) {
                /*
                 * INTL: For now we just treat the characters as binary
                 * data and display the lower byte.  Eventually this should
                 * be revised to handle international postscript fonts.
                 */

                p += Tcl_UtfToUniChar(p, &ch);
                c = UCHAR(ch & 0xff);
                if ((c == '(') || (c == ')') || (c == '\\') || (c < 0x20)
                        || (c >= UCHAR(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.
                     */

                    sprintf(buf + used, "\\%03o", c);
                    used += 4;
                } else {
                    buf[used++] = c;
                }
                if (used >= MAXUSE) {
                    buf[used] = '\0';
                    Tcl_AppendResult(interp, buf, (char *) NULL);
                    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';
            Tcl_AppendResult(interp, buf, (char *) NULL);
            used = 0;
        }
        chunkPtr++;
    }
    buf[used++] = ')';
    buf[used++] = '\n';
    buf[used] = '\0';
    Tcl_AppendResult(interp, buf, (char *) NULL);
}

/*
 *---------------------------------------------------------------------------
 *
 * ConfigAttributesObj --
 *
 *      Process command line options to fill in fields of a properly
 *      initialized font attributes structure.
 *
 * Results:
 *      A standard Tcl return value.  If TCL_ERROR is returned, an
 *      error message will be left in interp's result object.
 *
 * Side effects:
 *      The fields of the font attributes structure get filled in with
 *      information from argc/argv.  If an error occurs while parsing,
 *      the font attributes structure will contain all modifications
 *      specified in the command line options up to the point of the
 *      error.
 *
 *---------------------------------------------------------------------------
 */

static int
ConfigAttributesObj(interp, tkwin, objc, objv, faPtr)
    Tcl_Interp *interp;         /* Interp for error return. */
    Tk_Window tkwin;            /* For display on which font will be used. */
    int objc;                   /* Number of elements in argv. */
    Tcl_Obj *CONST objv[];      /* Command line options. */
    TkFontAttributes *faPtr;    /* Font attributes structure whose fields
                                 * are to be modified.  Structure must already
                                 * be properly initialized. */
{
    int i, n, index;
    Tcl_Obj *optionPtr, *valuePtr;
    char *value;
    
    for (i = 0; i < objc; i += 2) {
        optionPtr = objv[i];
        valuePtr = objv[i + 1];

        if (Tcl_GetIndexFromObj(interp, optionPtr, fontOpt, "option", 1,
                &index) != TCL_OK) {
            return TCL_ERROR;
        }
        if ((i+2 >= objc) && (objc & 1)) {
            /*
             * This test occurs after Tcl_GetIndexFromObj() so that
             * "font create xyz -xyz" will return the error message
             * that "-xyz" is a bad option, rather than that the value
             * for "-xyz" is missing.
             */

            Tcl_AppendResult(interp, "value for \"",
                    Tcl_GetString(optionPtr), "\" option missing",
                    (char *) NULL);
            return TCL_ERROR;
        }

        switch (index) {
            case FONT_FAMILY: {
                value = Tcl_GetString(valuePtr);
                faPtr->family = Tk_GetUid(value);
                break;
            }
            case FONT_SIZE: {
                if (Tcl_GetIntFromObj(interp, valuePtr, &n) != TCL_OK) {
                    return TCL_ERROR;
                }
                faPtr->size = n;
                break;
            }
            case FONT_WEIGHT: {
                n = TkFindStateNumObj(interp, optionPtr, weightMap, valuePtr);
                if (n == TK_FW_UNKNOWN) {
                    return TCL_ERROR;
                }
                faPtr->weight = n;
                break;
            }
            case FONT_SLANT: {
                n = TkFindStateNumObj(interp, optionPtr, slantMap, valuePtr);
                if (n == TK_FS_UNKNOWN) {
                    return TCL_ERROR;
                }
                faPtr->slant = n;
                break;
            }
            case FONT_UNDERLINE: {
                if (Tcl_GetBooleanFromObj(interp, valuePtr, &n) != TCL_OK) {
                    return TCL_ERROR;
                }
                faPtr->underline = n;
                break;
            }
            case FONT_OVERSTRIKE: {
                if (Tcl_GetBooleanFromObj(interp, valuePtr, &n) != TCL_OK) {
                    return TCL_ERROR;
                }
                faPtr->overstrike = n;
                break;
            }
        }
    }
    return TCL_OK;
}

/*
 *---------------------------------------------------------------------------
 *
 * GetAttributeInfoObj --
 *
 *      Return information about the font attributes as a Tcl list.
 *
 * Results:
 *      The return value is TCL_OK if the objPtr was non-NULL and
 *      specified a valid font attribute, TCL_ERROR otherwise.  If TCL_OK
 *      is returned, the interp's result object is modified to hold a
 *      description of either the current value of a single option, or a
 *      list of all options and their current values for the given font
 *      attributes.  If TCL_ERROR is returned, the interp's result is
 *      set to an error message describing that the objPtr did not refer
 *      to a valid option.
 *
 * Side effects:
 *      None.
 *
 *---------------------------------------------------------------------------
 */

static int
GetAttributeInfoObj(interp, faPtr, objPtr)
    Tcl_Interp *interp;                 /* Interp to hold result. */
    CONST TkFontAttributes *faPtr;      /* The font attributes to inspect. */
    Tcl_Obj *objPtr;                    /* If non-NULL, indicates the single
                                         * option whose value is to be
                                         * returned. Otherwise information is
                                         * returned for all options. */
{
    int i, index, start, end;
    char *str;
    Tcl_Obj *optionPtr, *valuePtr, *resultPtr;

    resultPtr = Tcl_GetObjResult(interp);

    start = 0;
    end = FONT_NUMFIELDS;
    if (objPtr != NULL) {
        if (Tcl_GetIndexFromObj(interp, objPtr, fontOpt, "option", TCL_EXACT,
                &index) != TCL_OK) {
            return TCL_ERROR;
        }
        start = index;
        end = index + 1;
    }

    valuePtr = NULL;
    for (i = start; i < end; i++) {
        switch (i) {
            case FONT_FAMILY:
                str = faPtr->family;
                valuePtr = Tcl_NewStringObj(str, ((str == NULL) ? 0 : -1));
                break;

            case FONT_SIZE:
                valuePtr = Tcl_NewIntObj(faPtr->size);
                break;

            case FONT_WEIGHT:
                str = TkFindStateString(weightMap, faPtr->weight);
                valuePtr = Tcl_NewStringObj(str, -1);
                break;
        
            case FONT_SLANT:
                str = TkFindStateString(slantMap, faPtr->slant);
                valuePtr = Tcl_NewStringObj(str, -1);
                break;

            case FONT_UNDERLINE:
                valuePtr = Tcl_NewBooleanObj(faPtr->underline);
                break;

            case FONT_OVERSTRIKE:
                valuePtr = Tcl_NewBooleanObj(faPtr->overstrike);
                break;
        }
        if (objPtr != NULL) {
            Tcl_SetObjResult(interp, valuePtr);
            return TCL_OK;
        }
        optionPtr = Tcl_NewStringObj(fontOpt[i], -1);
        Tcl_ListObjAppendElement(NULL, resultPtr, optionPtr);
        Tcl_ListObjAppendElement(NULL, resultPtr, valuePtr);
    }
    return TCL_OK;
}

/*
 *---------------------------------------------------------------------------
 *
 * ParseFontNameObj --
 *
 *      Converts a object into a set of font attributes that can be used
 *      to construct a font.
 *
 *      The string rep of the object can be one of the following forms:
 *              XLFD (see X documentation)
 *              "family [size] [style1 [style2 ...]"
 *              "-option value [-option value ...]"
 *
 * Results:
 *      The return value is TCL_ERROR if the object was syntactically
 *      invalid.  In that case an error message is left in interp's
 *      result object.  Otherwise, fills the font attribute buffer with
 *      the values parsed from the string and returns TCL_OK;
 *
 * Side effects:
 *      None.
 *
 *---------------------------------------------------------------------------
 */

static int
ParseFontNameObj(interp, tkwin, objPtr, faPtr)
    Tcl_Interp *interp;         /* Interp for error return.  Must not be
                                 * NULL. */
    Tk_Window tkwin;            /* For display on which font is used. */
    Tcl_Obj *objPtr;            /* Parseable font description object. */
    TkFontAttributes *faPtr;    /* Filled with attributes parsed from font
                                 * name.  Any attributes that were not
                                 * specified in font name are filled with
                                 * default values. */
{
    char *dash;
    int objc, result, i, n;
    Tcl_Obj **objv;
    char *string;
    
    TkInitFontAttributes(faPtr);

    string = Tcl_GetString(objPtr);
    if (*string == '-') {
        /*
         * This may be an XLFD or an "-option value" string.
         *
         * If the string begins with "-*" or a "-foundry-family-*" pattern,
         * then consider it an XLFD.  
         */

        if (string[1] == '*') {
            goto xlfd;
        }
        dash = strchr(string + 1, '-');
        if ((dash != NULL)
                && (!isspace(UCHAR(dash[-1])))) { /* INTL: ISO space */
            goto xlfd;
        }

        if (Tcl_ListObjGetElements(interp, objPtr, &objc, &objv) != TCL_OK) {
            return TCL_ERROR;
        }

        return ConfigAttributesObj(interp, tkwin, objc, objv, faPtr);
    }
    
    if (*string == '*') {
        /*
         * This is appears to be an XLFD.  Under Unix, all valid XLFDs were
         * already handled by TkpGetNativeFont.  If we are here, either we
         * have something that initially looks like an XLFD but isn't or we
         * have encountered an XLFD on Windows or Mac.
         */

        xlfd:
        result = TkFontParseXLFD(string, faPtr, NULL);
        if (result == TCL_OK) {
            return TCL_OK;
        }
    }

    /*
     * Wasn't an XLFD or "-option value" string.  Try it as a
     * "font size style" list.
     */

    if ((Tcl_ListObjGetElements(NULL, objPtr, &objc, &objv) != TCL_OK)
            || (objc < 1)) {
        Tcl_AppendResult(interp, "font \"", string, "\" doesn't exist",
                (char *) NULL);
        return TCL_ERROR;
    }

    faPtr->family = Tk_GetUid(Tcl_GetString(objv[0]));
    if (objc > 1) {
        if (Tcl_GetIntFromObj(interp, objv[1], &n) != TCL_OK) {
            return TCL_ERROR;
        }
        faPtr->size = n;
    }

    i = 2;
    if (objc == 3) {
        if (Tcl_ListObjGetElements(interp, objv[2], &objc, &objv) != TCL_OK) {
            return TCL_ERROR;
        }
        i = 0;
    }
    for ( ; i < objc; i++) {
        n = TkFindStateNumObj(NULL, NULL, weightMap, objv[i]);
        if (n != TK_FW_UNKNOWN) {
            faPtr->weight = n;
            continue;
        }
        n = TkFindStateNumObj(NULL, NULL, slantMap, objv[i]);
        if (n != TK_FS_UNKNOWN) {
            faPtr->slant = n;
            continue;
        }
        n = TkFindStateNumObj(NULL, NULL, underlineMap, objv[i]);
        if (n != 0) {
            faPtr->underline = n;
            continue;
        }
        n = TkFindStateNumObj(NULL, NULL, overstrikeMap, objv[i]);
        if (n != 0) {
            faPtr->overstrike = n;
            continue;
        }

        /*
         * Unknown style.
         */

        Tcl_AppendResult(interp, "unknown font style \"",
                Tcl_GetString(objv[i]), "\"", (char *) NULL);
        return TCL_ERROR;
    }
    return TCL_OK;
}

/*
 *---------------------------------------------------------------------------
 *
 * NewChunk --
 *
 *      Helper function for Tk_ComputeTextLayout().  Encapsulates a
 *      measured set of characters in a chunk that can be quickly
 *      drawn.
 *
 * Results:
 *      A pointer to the new chunk in the text layout.
 *
 * Side effects:
 *      The text layout is reallocated to hold more chunks as necessary.
 *
 *      Currently, Tk_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.
 *
 *---------------------------------------------------------------------------
 */
static LayoutChunk *
NewChunk(layoutPtrPtr, maxPtr, start, numBytes, curX, newX, y)
    TextLayout **layoutPtrPtr;
    int *maxPtr;
    CONST char *start;
    int numBytes;
    int curX;
    int newX;
    int y;
{
    TextLayout *layoutPtr;
    LayoutChunk *chunkPtr;
    int maxChunks, numChars;
    size_t s;
    
    layoutPtr = *layoutPtrPtr;
    maxChunks = *maxPtr;
    if (layoutPtr->numChunks == maxChunks) {
        maxChunks *= 2;
        s = sizeof(TextLayout) + ((maxChunks - 1) * sizeof(LayoutChunk));
        layoutPtr = (TextLayout *) ckrealloc((char *) layoutPtr, s);

        *layoutPtrPtr = layoutPtr;
        *maxPtr = maxChunks;
    }
    numChars = Tcl_NumUtfChars(start, numBytes);
    chunkPtr = &layoutPtr->chunks[layoutPtr->numChunks];
    chunkPtr->start             = start;
    chunkPtr->numBytes          = numBytes;
    chunkPtr->numChars          = numChars;
    chunkPtr->numDisplayChars   = numChars;
    chunkPtr->x                 = curX;
    chunkPtr->y                 = y;
    chunkPtr->totalWidth        = newX - curX;
    chunkPtr->displayWidth      = newX - curX;
    layoutPtr->numChunks++;

    return chunkPtr;
}

/*
 *---------------------------------------------------------------------------
 *
 * TkFontParseXLFD --
 *
 *      Break up a fully specified XLFD into a set of font attributes.
 *
 * Results:
 *      Return value is TCL_ERROR if string was not a fully specified XLFD.
 *      Otherwise, fills font attribute buffer with the values parsed
 *      from the XLFD and returns TCL_OK.  
 *
 * Side effects:
 *      None.
 *
 *---------------------------------------------------------------------------
 */

int
TkFontParseXLFD(string, faPtr, xaPtr)
    CONST char *string;         /* Parseable font description string. */
    TkFontAttributes *faPtr;    /* Filled with attributes parsed from font
                                 * name.  Any attributes that were not
                                 * specified in font name are filled with
                                 * default values. */
    TkXLFDAttributes *xaPtr;    /* Filled with X-specific attributes parsed
                                 * from font name.  Any attributes that were
                                 * not specified in font name are filled with
                                 * default values.  May be NULL if such
                                 * information is not desired. */
{
    char *src;
    CONST char *str;
    int i, j;
    char *field[XLFD_NUMFIELDS + 2];
    Tcl_DString ds;
    TkXLFDAttributes xa;
    
    if (xaPtr == NULL) {
        xaPtr = &xa;
    }
    TkInitFontAttributes(faPtr);
    TkInitXLFDAttributes(xaPtr);

    memset(field, '\0', sizeof(field));

    str = string;
    if (*str == '-') {
        str++;
    }

    Tcl_DStringInit(&ds);
    Tcl_DStringAppend(&ds, (char *) str, -1);
    src = Tcl_DStringValue(&ds);

    field[0] = src;
    for (i = 0; *src != '\0'; src++) {
        if (!(*src & 0x80)
                && Tcl_UniCharIsUpper(UCHAR(*src))) {
            *src = (char) Tcl_UniCharToLower(UCHAR(*src));
        }
        if (*src == '-') {
            i++;
            if (i == XLFD_NUMFIELDS) {
                continue;
            }
            *src = '\0';
            field[i] = src + 1;
            if (i > XLFD_NUMFIELDS) {
                break;
            }
        }
    }

    /*
     * 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 right by one, so the number gets interpreted
     * as a pixelsize.  This fix is so that we don't get a million reports
     * that "it works under X (as a native font name), but gives a syntax
     * error under Windows (as a parsed set of attributes)".
     */

    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] = NULL;
            i++;
        }
    }

    /*
     * Bail if we don't have enough of the fields (up to pointsize).
     */

    if (i < XLFD_FAMILY) {
        Tcl_DStringFree(&ds);
        return TCL_ERROR;
    }

    if (FieldSpecified(field[XLFD_FOUNDRY])) {
        xaPtr->foundry = Tk_GetUid(field[XLFD_FOUNDRY]);
    }

    if (FieldSpecified(field[XLFD_FAMILY])) {
        faPtr->family = Tk_GetUid(field[XLFD_FAMILY]);
    }
    if (FieldSpecified(field[XLFD_WEIGHT])) {
        faPtr->weight = TkFindStateNum(NULL, NULL, xlfdWeightMap,
                field[XLFD_WEIGHT]);
    }
    if (FieldSpecified(field[XLFD_SLANT])) {
        xaPtr->slant = TkFindStateNum(NULL, NULL, xlfdSlantMap,
                field[XLFD_SLANT]);
        if (xaPtr->slant == TK_FS_ROMAN) {
            faPtr->slant = TK_FS_ROMAN;
        } else {
            faPtr->slant = TK_FS_ITALIC;
        }
    }
    if (FieldSpecified(field[XLFD_SETWIDTH])) {
        xaPtr->setwidth = TkFindStateNum(NULL, NULL, xlfdSetwidthMap,
                field[XLFD_SETWIDTH]);
    }

    /* XLFD_ADD_STYLE ignored. */

    /*
     * Pointsize in tenths of a point, but treat it as tenths of a pixel
     * for historical compatibility.
     */

    faPtr->size = 12;

    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.
             */

            faPtr->size = atoi(field[XLFD_POINT_SIZE] + 1);
        } else if (Tcl_GetInt(NULL, field[XLFD_POINT_SIZE],
                &faPtr->size) == TCL_OK) {
            faPtr->size /= 10;
        } else {
            return TCL_ERROR;
        }
    }

    /*
     * 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.
             */

            faPtr->size = atoi(field[XLFD_PIXEL_SIZE] + 1);
        } else if (Tcl_GetInt(NULL, field[XLFD_PIXEL_SIZE],
                &faPtr->size) != TCL_OK) {
            return TCL_ERROR;
        }
    }

    faPtr->size = -faPtr->size;

    /* XLFD_RESOLUTION_X ignored. */

    /* XLFD_RESOLUTION_Y ignored. */

    /* XLFD_SPACING ignored. */

    /* XLFD_AVERAGE_WIDTH ignored. */

    if (FieldSpecified(field[XLFD_CHARSET])) {
        xaPtr->charset = Tk_GetUid(field[XLFD_CHARSET]);
    } else {
        xaPtr->charset = Tk_GetUid("iso8859-1");
    }
    Tcl_DStringFree(&ds);
    return TCL_OK;
}

/*
 *---------------------------------------------------------------------------
 *
 * FieldSpecified --
 *
 *      Helper function for TkParseXLFD().  Determines if a field in the
 *      XLFD was set to a non-null, non-don't-care value.
 *
 * Results:
 *      The return value is 0 if the field in the XLFD was not set and
 *      should be ignored, non-zero otherwise.
 *
 * Side effects:
 *      None.
 *
 *---------------------------------------------------------------------------
 */

static int
FieldSpecified(field)
    CONST char *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. */
{
    char ch;

    if (field == NULL) {
        return 0;
    }
    ch = field[0];
    return (ch != '*' && ch != '?');
}

/*
 *---------------------------------------------------------------------------
 *
 * TkFontGetPixels --
 *
 *      Given a font size specification (as described in the TkFontAttributes
 *      structure) return the number of pixels it represents.
 *
 * Results:
 *      As above.
 *
 * Side effects:
 *      None.
 *
 *---------------------------------------------------------------------------
 */
 
int
TkFontGetPixels(tkwin, size)
    Tk_Window tkwin;            /* For point->pixel conversion factor. */
    int size;                   /* Font size. */
{
    double d;

    if (size < 0) {
        return -size;
    }

    d = size * 25.4 / 72.0;
    d *= WidthOfScreen(Tk_Screen(tkwin));
    d /= WidthMMOfScreen(Tk_Screen(tkwin));
    return (int) (d + 0.5);
}

/*
 *---------------------------------------------------------------------------
 *
 * TkFontGetPoints --
 *
 *      Given a font size specification (as described in the TkFontAttributes
 *      structure) return the number of points it represents.
 *
 * Results:
 *      As above.
 *
 * Side effects:
 *      None.
 *
 *---------------------------------------------------------------------------
 */
 
int
TkFontGetPoints(tkwin, size)
    Tk_Window tkwin;            /* For pixel->point conversion factor. */
    int size;                   /* Font size. */
{
    double d;

    if (size >= 0) {
        return size;
    }

    d = -size * 72.0 / 25.4;
    d *= WidthMMOfScreen(Tk_Screen(tkwin));
    d /= WidthOfScreen(Tk_Screen(tkwin));
    return (int) (d + 0.5);
}

/*
 *-------------------------------------------------------------------------
 *
 * TkFontGetAliasList --
 *
 *      Given a font name, find the list of all aliases for that font
 *      name.  One of the names in this list will probably be the name
 *      that this platform expects when asking for the font.
 *
 * Results:
 *      As above.  The return value is NULL if the font name has no 
 *      aliases.
 *
 * Side effects:
 *      None.
 *
 *-------------------------------------------------------------------------
 */
        
char **
TkFontGetAliasList(faceName)
    CONST char *faceName;       /* Font name to test for aliases. */
{   
    int i, j;

    for (i = 0; fontAliases[i] != NULL; i++) {
        for (j = 0; fontAliases[i][j] != NULL; j++) {
            if (strcasecmp(faceName, fontAliases[i][j]) == 0) {
                return fontAliases[i];
            }
        }
    }
    return NULL;
}

/*
 *-------------------------------------------------------------------------
 *
 * TkFontGetFallbacks --
 *
 *      Get the list of font fallbacks that the platform-specific code
 *      can use to try to find the closest matching font the name 
 *      requested.
 *
 * Results:
 *      As above.
 *
 * Side effects:
 *      None.
 *
 *-------------------------------------------------------------------------
 */
        
char ***
TkFontGetFallbacks()
{
    return fontFallbacks;
}

/*
 *-------------------------------------------------------------------------
 *
 * TkFontGetGlobalClass --
 *
 *      Get the list of fonts to try if the requested font name does not
 *      exist and no fallbacks for that font name could be used either.
 *      The names in this list are considered preferred over all the other
 *      font names in the system when looking for a last-ditch fallback.
 *
 * Results:
 *      As above.
 *
 * Side effects:
 *      None.
 *
 *-------------------------------------------------------------------------
 */
        
char **
TkFontGetGlobalClass()
{
    return globalFontClass;
}

/*
 *-------------------------------------------------------------------------
 *
 * TkFontGetSymbolClass --
 *
 *      Get the list of fonts that are symbolic; used if the operating 
 *      system cannot apriori identify symbolic fonts on its own.
 *
 * Results:
 *      As above.
 *
 * Side effects:
 *      None.
 *
 *-------------------------------------------------------------------------
 */
        
char **
TkFontGetSymbolClass()
{
    return symbolClass;
}

/*
 *----------------------------------------------------------------------
 *
 * TkDebugFont --
 *
 *      This procedure returns debugging information about a font.
 *
 * Results:
 *      The return value is a list with one sublist for each TkFont
 *      corresponding to "name".  Each sublist has two elements that
 *      contain the resourceRefCount and objRefCount fields from the
 *      TkFont structure.
 *
 * Side effects:
 *      None.
 *
 *----------------------------------------------------------------------
 */

Tcl_Obj *
TkDebugFont(tkwin, name)
    Tk_Window tkwin;            /* The window in which the font will be
                                 * used (not currently used). */
    char *name;                 /* Name of the desired color. */
{
    TkFont *fontPtr;
    Tcl_HashEntry *hashPtr;
    Tcl_Obj *resultPtr, *objPtr;

    resultPtr = Tcl_NewObj();
    hashPtr = Tcl_FindHashEntry(
            &((TkWindow *) tkwin)->mainPtr->fontInfoPtr->fontCache, name);
    if (hashPtr != NULL) {
        fontPtr = (TkFont *) Tcl_GetHashValue(hashPtr);
        if (fontPtr == NULL) {
            panic("TkDebugFont found empty hash table entry");
        }
        for ( ; (fontPtr != NULL); fontPtr = fontPtr->nextPtr) {
            objPtr = Tcl_NewObj();
            Tcl_ListObjAppendElement(NULL, objPtr,
                    Tcl_NewIntObj(fontPtr->resourceRefCount));
            Tcl_ListObjAppendElement(NULL, objPtr,
                    Tcl_NewIntObj(fontPtr->objRefCount)); 
            Tcl_ListObjAppendElement(NULL, resultPtr, objPtr);
        }
    }
    return resultPtr;
}

/* End of tkfont.c */