Bigtile使用時にマップ画面の左端がその場所地形によっては正しくアップデート

[hengband/hengband.git] / src / z-term.c

/* File: z-term.c */

/*
 * Copyright (c) 1997 Ben Harrison
 *
 * This software may be copied and distributed for educational, research,
 * and not for profit purposes provided that this copyright and statement
 * are included in all such copies.
 */

/* Purpose: a generic, efficient, terminal window package -BEN- */
#include "angband.h"

#include "z-term.h"

#include "z-virt.h"


#ifdef JP
#define KANJI1  0x10
#define KANJI2  0x20
#define KANJIC  0x0f
/*
 * Á´³Ñʸ»úÂбþ¡£
 * °À­¤ËÁ´³Ñʸ»ú¤Î£±¥Ð¥¤¥ÈÌÜ¡¢£²¥Ð¥¤¥ÈÌܤ⵭²±¡£
 * By FIRST
 */
#endif
/*
 * This file provides a generic, efficient, terminal window package,
 * which can be used not only on standard terminal environments such
 * as dumb terminals connected to a Unix box, but also in more modern
 * "graphic" environments, such as the Macintosh or Unix/X11.
 *
 * Each "window" works like a standard "dumb terminal", that is, it
 * can display a two dimensional array of grids containing colored
 * textual symbols, plus an optional cursor, and it can be used to
 * get keypress events from the user.
 *
 * In fact, this package can simply be used, if desired, to support
 * programs which will look the same on a dumb terminal as they do
 * on a graphic platform such as the Macintosh.
 *
 * This package was designed to help port the game "Angband" to a wide
 * variety of different platforms.  Angband, like many other games in
 * the "rogue-like" heirarchy, requires, at the minimum, the ability
 * to display "colored textual symbols" in a standard 80x24 "window",
 * such as that provided by most dumb terminals, and many old personal
 * computers, and to check for "keypresses" from the user.  The major
 * concerns were thus portability and efficiency, so Angband could be
 * easily ported to many different systems, with minimal effort, and
 * yet would run quickly on each of these systems, no matter what kind
 * of underlying hardware/software support was being used.
 *
 * It is important to understand the differences between the older
 * "dumb terminals" and the newer "graphic interface" machines, since
 * this package was designed to work with both types of systems.
 *
 * New machines:
 *   waiting for a keypress is complex
 *   checking for a keypress is often cheap
 *   changing "colors" may be expensive
 *   the "color" of a "blank" is rarely important
 *   moving the "cursor" is relatively cheap
 *   use a "software" cursor (only moves when requested)
 *   drawing characters normally will not erase old ones
 *   drawing a character on the cursor often erases it
 *   may have fast routines for "clear a region"
 *   the bottom right corner is usually not special
 *
 * Old machines:
 *   waiting for a keypress is simple
 *   checking for a keypress is often expensive
 *   changing "colors" is usually cheap
 *   the "color" of a "blank" may be important
 *   moving the "cursor" may be expensive
 *   use a "hardware" cursor (moves during screen updates)
 *   drawing new symbols automatically erases old ones
 *   characters may only be drawn at the cursor location
 *   drawing a character on the cursor will move the cursor
 *   may have fast routines for "clear entire window"
 *   may have fast routines for "clear to end of line"
 *   the bottom right corner is often dangerous
 *
 *
 * This package provides support for multiple windows, each of an
 * arbitrary size (up to 255x255), each with its own set of flags,
 * and its own hooks to handle several low-level procedures which
 * differ from platform to platform.  Then the main program simply
 * creates one or more "term" structures, setting the various flags
 * and hooks in a manner appropriate for the current platform, and
 * then it can use the various "term" structures without worrying
 * about the underlying platform.
 *
 *
 * This package allows each "grid" in each window to hold an attr/char
 * pair, with each ranging from 0 to 255, and makes very few assumptions
 * about the meaning of any attr/char values.  Normally, we assume that
 * "attr 0" is "black", with the semantics that "black" text should be
 * sent to "Term_wipe()" instead of "Term_text()", but this sematics is
 * modified if either the "always_pict" or the "always_text" flags are
 * set.  We assume that "char 0" is "dangerous", since placing such a
 * "char" in the middle of a string "terminates" the string, and usually
 * we prevent its use.
 *
 * Finally, we use a special attr/char pair, defaulting to "attr 0" and
 * "char 32", also known as "black space", when we "erase" or "clear"
 * any window, but this pair can be redefined to any pair, including
 * the standard "white space", or the bizarre "emptiness" ("attr 0"
 * and "char 0"), as long as various obscure restrictions are met.
 *
 *
 * This package provides several functions which allow a program to
 * interact with the "term" structures.  Most of the functions allow
 * the program to "request" certain changes to the current "term",
 * such as moving the cursor, drawing an attr/char pair, erasing a
 * region of grids, hiding the cursor, etc.  Then there is a special
 * function which causes all of the "pending" requests to be performed
 * in an efficient manner.  There is another set of functions which
 * allow the program to query the "requested state" of the current
 * "term", such as asking for the cursor location, or what attr/char
 * is at a given location, etc.  There is another set of functions
 * dealing with "keypress" events, which allows the program to ask if
 * the user has pressed any keys, or to forget any keys the user pressed.
 * There is a pair of functions to allow this package to memorize the
 * contents of the current "term", and to restore these contents at
 * a later time.  There is a special function which allows the program
 * to specify which "term" structure should be the "current" one.  At
 * the lowest level, there is a set of functions which allow a new
 * "term" to be initialized or destroyed, and which allow this package,
 * or a program, to access the special "hooks" defined for the current
 * "term", and a set of functions which those "hooks" can use to inform
 * this package of the results of certain occurances, for example, one
 * such function allows this package to learn about user keypresses,
 * detected by one of the special "hooks".
 *
 * We provide, among other things, the functions "Term_keypress()"
 * to "react" to keypress events, and "Term_redraw()" to redraw the
 * entire window, plus "Term_resize()" to note a new size.
 *
 *
 * Note that the current "term" contains two "window images".  One of
 * these images represents the "requested" contents of the "term", and
 * the other represents the "actual" contents of the "term", at the time
 * of the last performance of pending requests.  This package uses these
 * two images to determine the "minimal" amount of work needed to make
 * the "actual" contents of the "term" match the "requested" contents of
 * the "term".  This method is not perfect, but it often reduces the
 * amount of work needed to perform the pending requests, which thus
 * increases the speed of the program itself.  This package promises
 * that the requested changes will appear to occur either "all at once"
 * or in a "top to bottom" order.  In addition, a "cursor" is maintained,
 * and this cursor is updated along with the actual window contents.
 *
 * Currently, the "Term_fresh()" routine attempts to perform the "minimum"
 * number of physical updates, in terms of total "work" done by the hooks
 * Term_wipe(), Term_text(), and Term_pict(), making use of the fact that
 * adjacent characters of the same color can both be drawn together using
 * the "Term_text()" hook, and that "black" text can often be sent to the
 * "Term_wipe()" hook instead of the "Term_text()" hook, and if something
 * is already displayed in a window, then it is not necessary to display
 * it again.  Unfortunately, this may induce slightly non-optimal results
 * in some cases, in particular, those in which, say, a string of ten
 * characters needs to be written, but the fifth character has already
 * been displayed.  Currently, this will cause the "Term_text()" routine
 * to be called once for each half of the string, instead of once for the
 * whole string, which, on some machines, may be non-optimal behavior.
 *
 * The new formalism includes a "displayed" screen image (old) which
 * is actually seen by the user, a "requested" screen image (scr)
 * which is being prepared for display, a "memorized" screen image
 * (mem) which is used to save and restore screen images, and a
 * "temporary" screen image (tmp) which is currently unused.
 *
 *
 * Several "flags" are available in each "term" to allow the underlying
 * visual system (which initializes the "term" structure) to "optimize"
 * the performance of this package for the given system, or to request
 * certain behavior which is helpful/required for the given system.
 *
 * The "soft_cursor" flag indicates the use of a "soft" cursor, which
 * only moves when explicitly requested,and which is "erased" when
 * any characters are drawn on top of it.  This flag is used for all
 * "graphic" systems which handle the cursor by "drawing" it.
 *
 * The "icky_corner" flag indicates that the bottom right "corner"
 * of the windows are "icky", and "printing" anything there may
 * induce "messy" behavior, such as "scrolling".  This flag is used
 * for most old "dumb terminal" systems.
 *
 *
 * The "term" structure contains the following function "hooks":
 *
 *   Term->init_hook = Init the term
 *   Term->nuke_hook = Nuke the term
 *   Term->user_hook = Perform user actions
 *   Term->xtra_hook = Perform extra actions
 *   Term->curs_hook = Draw (or Move) the cursor
 *   Term->wipe_hook = Draw some blank spaces
 *   Term->text_hook = Draw some text in the window
 *   Term->pict_hook = Draw some attr/chars in the window
 *
 * The "Term->user_hook" hook provides a simple hook to an implementation
 * defined function, with application defined semantics.  It is available
 * to the program via the "Term_user()" function.
 *
 * The "Term->xtra_hook" hook provides a variety of different functions,
 * based on the first parameter (which should be taken from the various
 * TERM_XTRA_* defines) and the second parameter (which may make sense
 * only for some first parameters).  It is available to the program via
 * the "Term_xtra()" function, though some first parameters are only
 * "legal" when called from inside this package.
 *
 * The "Term->curs_hook" hook provides this package with a simple way
 * to "move" or "draw" the cursor to the grid "x,y", depending on the
 * setting of the "soft_cursor" flag.  Note that the cursor is never
 * redrawn if "nothing" has happened to the screen (even temporarily).
 * This hook is required.
 *
 * The "Term->wipe_hook" hook provides this package with a simple way
 * to "erase", starting at "x,y", the next "n" grids.  This hook assumes
 * that the input is valid.  This hook is required, unless the setting
 * of the "always_pict" or "always_text" flags makes it optional.
 *
 * The "Term->text_hook" hook provides this package with a simple way
 * to "draw", starting at "x,y", the "n" chars contained in "cp", using
 * the attr "a".  This hook assumes that the input is valid, and that
 * "n" is between 1 and 256 inclusive, but it should NOT assume that
 * the contents of "cp" are null-terminated.  This hook is required,
 * unless the setting of the "always_pict" flag makes it optional.
 *
 * The "Term->pict_hook" hook provides this package with a simple way
 * to "draw", starting at "x,y", the "n" attr/char pairs contained in
 * the arrays "ap" and "cp".  This hook assumes that the input is valid,
 * and that "n" is between 1 and 256 inclusive, but it should NOT assume
 * that the contents of "cp" are null-terminated.  This hook is optional,
 * unless the setting of the "always_pict" or "higher_pict" flags make
 * it required.  Note that recently, this hook was changed from taking
 * a byte "a" and a char "c" to taking a length "n", an array of bytes
 * "ap" and an array of chars "cp".  Old implementations of this hook
 * should now iterate over all "n" attr/char pairs.
 *
 *
 * The game "Angband" uses a set of files called "main-xxx.c", for
 * various "xxx" suffixes.  Most of these contain a function called
 * "init_xxx()", that will prepare the underlying visual system for
 * use with Angband, and then create one or more "term" structures,
 * using flags and hooks appropriate to the given platform, so that
 * the "main()" function can call one (or more) of the "init_xxx()"
 * functions, as appropriate, to prepare the required "term" structs
 * (one for each desired sub-window), and these "init_xxx()" functions
 * are called from a centralized "main()" function in "main.c".  Other
 * "main-xxx.c" systems contain their own "main()" function which, in
 * addition to doing everything needed to initialize the actual program,
 * also does everything that the normal "init_xxx()" functions would do.
 *
 * The game "Angband" defines, in addition to "attr 0", all of the
 * attr codes from 1 to 15, using definitions in "defines.h", and
 * thus the "main-xxx.c" files used by Angband must handle these
 * attr values correctly.  Also, they must handle all other attr
 * values, though they may do so in any way they wish, for example,
 * by always taking every attr code mod 16.  Many of the "main-xxx.c"
 * files use "white space" ("attr 1" / "char 32") to "erase" or "clear"
 * any window, for efficiency.
 *
 * The game "Angband" uses the "Term_user" hook to allow any of the
 * "main-xxx.c" files to interact with the user, by calling this hook
 * whenever the user presses the "!" key when the game is waiting for
 * a new command.  This could be used, for example, to provide "unix
 * shell commands" to the Unix versions of the game.
 *
 * See "main-xxx.c" for a simple skeleton file which can be used to
 * create a "visual system" for a new platform when porting Angband.
 */






/*
 * The current "term"
 */
term *Term = NULL;




/*** Local routines ***/


/*
 * Nuke a term_win (see below)
 */
static errr term_win_nuke(term_win *s, int w, int h)
{
        /* Free the window access arrays */
        C_KILL(s->a, h, byte*);
        C_KILL(s->c, h, char*);

        /* Free the window content arrays */
        C_KILL(s->va, h * w, byte);
        C_KILL(s->vc, h * w, char);

#ifdef USE_TRANSPARENCY

        /* Free the terrain access arrays */
        C_KILL(s->ta, h, byte*);
        C_KILL(s->tc, h, char*);

        /* Free the terrain content arrays */
        C_KILL(s->vta, h * w, byte);
        C_KILL(s->vtc, h * w, char);

#endif /* USE_TRANSPARENCY */

        /* Success */
        return (0);
}


/*
 * Initialize a "term_win" (using the given window size)
 */
static errr term_win_init(term_win *s, int w, int h)
{
        int y;

        /* Make the window access arrays */
        C_MAKE(s->a, h, byte*);
        C_MAKE(s->c, h, char*);

        /* Make the window content arrays */
        C_MAKE(s->va, h * w, byte);
        C_MAKE(s->vc, h * w, char);

#ifdef USE_TRANSPARENCY

        /* Make the terrain access arrays */
        C_MAKE(s->ta, h, byte*);
        C_MAKE(s->tc, h, char*);

        /* Make the terrain content arrays */
        C_MAKE(s->vta, h * w, byte);
        C_MAKE(s->vtc, h * w, char);

#endif /* USE_TRANSPARENCY */


        /* Prepare the window access arrays */
        for (y = 0; y < h; y++)
        {
                s->a[y] = s->va + w * y;
                s->c[y] = s->vc + w * y;

#ifdef USE_TRANSPARENCY

                s->ta[y] = s->vta + w * y;
                s->tc[y] = s->vtc + w * y;

#endif /* USE_TRANSPARENCY */

        }

        /* Success */
        return (0);
}


/*
 * Copy a "term_win" from another
 */
static errr term_win_copy(term_win *s, term_win *f, int w, int h)
{
        int x, y;

        /* Copy contents */
        for (y = 0; y < h; y++)
        {
                byte *f_aa = f->a[y];
                char *f_cc = f->c[y];

                byte *s_aa = s->a[y];
                char *s_cc = s->c[y];

#ifdef USE_TRANSPARENCY

                byte *f_taa = f->ta[y];
                char *f_tcc = f->tc[y];

                byte *s_taa = s->ta[y];
                char *s_tcc = s->tc[y];

#endif /* USE_TRANSPARENCY */

                for (x = 0; x < w; x++)
                {
                        *s_aa++ = *f_aa++;
                        *s_cc++ = *f_cc++;

#ifdef USE_TRANSPARENCY
                        *s_taa++ = *f_taa++;
                        *s_tcc++ = *f_tcc++;
#endif /* USE_TRANSPARENCY */
                }
        }

        /* Copy cursor */
        s->cx = f->cx;
        s->cy = f->cy;
        s->cu = f->cu;
        s->cv = f->cv;

        /* Success */
        return (0);
}



/*** External hooks ***/


/*
 * Execute the "Term->user_hook" hook, if available (see above).
 */
errr Term_user(int n)
{
        /* Verify the hook */
        if (!Term->user_hook) return (-1);

        /* Call the hook */
        return ((*Term->user_hook)(n));
}

/*
 * Execute the "Term->xtra_hook" hook, if available (see above).
 */
errr Term_xtra(int n, int v)
{
        /* Verify the hook */
        if (!Term->xtra_hook) return (-1);

#ifdef CHUUKEI
        if( n == TERM_XTRA_CLEAR || n == TERM_XTRA_FRESH || n == TERM_XTRA_SHAPE )
          send_xtra_to_chuukei_server(n);
#endif
        /* Call the hook */
        return ((*Term->xtra_hook)(n, v));
}



/*** Fake hooks ***/


/*
 * Hack -- fake hook for "Term_curs()" (see above)
 */
static errr Term_curs_hack(int x, int y)
{
        /* Compiler silliness */
        if (x || y) return (-2);

        /* Oops */
        return (-1);
}

/*
 * Hack -- fake hook for "Term_wipe()" (see above)
 */
static errr Term_wipe_hack(int x, int y, int n)
{
        /* Compiler silliness */
        if (x || y || n) return (-2);

        /* Oops */
        return (-1);
}

/*
 * Hack -- fake hook for "Term_text()" (see above)
 */
#ifdef JP
static errr Term_text_hack(int x, int y, int n, byte a, cptr cp)
#else
static errr Term_text_hack(int x, int y, int n, byte a, const char *cp)
#endif

{
        /* Compiler silliness */
        if (x || y || n || a || cp) return (-2);

        /* Oops */
        return (-1);
}

/*
 * Hack -- fake hook for "Term_pict()" (see above)
 */
#ifdef USE_TRANSPARENCY
static errr Term_pict_hack(int x, int y, int n, const byte *ap, const char *cp, const byte *tap, const char *tcp)
#else /* USE_TRANSPARENCY */
static errr Term_pict_hack(int x, int y, int n, const byte *ap, const char *cp)
#endif /* USE_TRANSPARENCY */
{
        /* Compiler silliness */
#ifdef USE_TRANSPARENCY
        if (x || y || n || ap || cp || tap || tcp) return (-2);
#else /* USE_TRANSPARENCY */
        if (x || y || n || ap || cp) return (-2);
#endif /* USE_TRANSPARENCY */

        /* Oops */
        return (-1);
}



/*** Efficient routines ***/


/*
 * Mentally draw an attr/char at a given location
 *
 * Assumes given location and values are valid.
 */
#ifdef USE_TRANSPARENCY
void Term_queue_char(int x, int y, byte a, char c, byte ta, char tc)
#else /* USE_TRANSPARENCY */
void Term_queue_char(int x, int y, byte a, char c)
#endif /* USE_TRANSPARENCY */
{
        term_win *scrn = Term->scr; 
        
        byte *scr_aa = &scrn->a[y][x];
        char *scr_cc = &scrn->c[y][x];

#ifdef USE_TRANSPARENCY

        byte *scr_taa = &scrn->ta[y][x];
        char *scr_tcc = &scrn->tc[y][x];

        /* Hack -- Ignore non-changes */
        if ((*scr_aa == a) && (*scr_cc == c) &&
                 (*scr_taa == ta) && (*scr_tcc == tc)) return;

#else /* USE_TRANSPARENCY */

        /* Hack -- Ignore non-changes */
        if ((*scr_aa == a) && (*scr_cc == c)) return;

#endif /* USE_TRANSPARENCY */

        /* Save the "literal" information */
        *scr_aa = a;
        *scr_cc = c;

#ifdef USE_TRANSPARENCY

        *scr_taa = ta;
        *scr_tcc = tc;

#endif /* USE_TRANSPARENCY */

        /* Check for new min/max row info */
        if (y < Term->y1) Term->y1 = y;
        if (y > Term->y2) Term->y2 = y;

        /* Check for new min/max col info for this row */
        if (x < Term->x1[y]) Term->x1[y] = x;
        if (x > Term->x2[y]) Term->x2[y] = x;
}


/*
 * Mentally draw a string of attr/chars at a given location
 *
 * Assumes given location and values are valid.
 *
 * This function is designed to be fast, with no consistancy checking.
 * It is used to update the map in the game.
 */
#ifdef USE_TRANSPARENCY
void Term_queue_line(int x, int y, int n, byte *a, char *c, byte *ta, char *tc)
#else /* USE_TRANSPARENCY */
void Term_queue_line(int x, int y, int n, byte *a, char *c)
#endif /* USE_TRANSPARENCY */
{
        term_win *scrn = Term->scr;

        int x1 = -1;
        int x2 = -1;

        byte *scr_aa = &scrn->a[y][x];
        char *scr_cc = &scrn->c[y][x];

#ifdef USE_TRANSPARENCY

        byte *scr_taa = &scrn->ta[y][x];
        char *scr_tcc = &scrn->tc[y][x];

#endif /* USE_TRANSPARENCY */

        while (n--)
        {

#ifdef USE_TRANSPARENCY

                /* Hack -- Ignore non-changes */
                if ((*scr_aa == *a) && (*scr_cc == *c) &&
                        (*scr_taa == *ta) && (*scr_tcc == *tc))
                {
                        x++;
                        a++;
                        c++;
                        ta++;
                        tc++;
                        scr_aa++;
                        scr_cc++;
                        scr_taa++;
                        scr_tcc++;
                        continue;
                }

                /* Save the "literal" information */
                *scr_taa++ = *ta++;
                *scr_tcc++ = *tc++;

#else /* USE_TRANSPARENCY */

                /* Hack -- Ignore non-changes */
                if ((*scr_aa == *a) && (*scr_cc == *c))
                {
                        x++;
                        a++;
                        c++;
                        scr_aa++;
                        scr_cc++;
                        continue;
                }

#endif /* USE_TRANSPARENCY */

                /* Save the "literal" information */
                *scr_aa++ = *a++;
                *scr_cc++ = *c++;

                /* Track minimum changed column */
                if (x1 < 0) x1 = x;

                /* Track maximum changed column */
                x2 = x;

                x++;
        }

        /* Expand the "change area" as needed */
        if (x1 >= 0)
        {
                /* Check for new min/max row info */
                if (y < Term->y1) Term->y1 = y;
                if (y > Term->y2) Term->y2 = y;

                /* Check for new min/max col info in this row */
                if (x1 < Term->x1[y]) Term->x1[y] = x1;
                if (x2 > Term->x2[y]) Term->x2[y] = x2;
        }
}



/*
 * Mentally draw some attr/chars at a given location
 *
 * Assumes that (x,y) is a valid location, that the first "n" characters
 * of the string "s" are all valid (non-zero), and that (x+n-1,y) is also
 * a valid location, so the first "n" characters of "s" can all be added
 * starting at (x,y) without causing any illegal operations.
 */
void Term_queue_chars(int x, int y, int n, byte a, cptr s)
{
        int x1 = -1, x2 = -1;

        byte *scr_aa = Term->scr->a[y];
#ifdef JP
        unsigned char *scr_cc = (unsigned char *)Term->scr->c[y];

#ifdef USE_TRANSPARENCY
        byte *scr_taa = Term->scr->ta[y];
        unsigned char *scr_tcc = Term->scr->tc[y];
#endif /* USE_TRANSPARENCY */

#else
        char *scr_cc = Term->scr->c[y];

#ifdef USE_TRANSPARENCY

        byte *scr_taa = Term->scr->ta[y];
        char *scr_tcc = Term->scr->tc[y];

#endif /* USE_TRANSPARENCY */
#endif


#ifdef JP
        /* ɽ¼¨Ê¸»ú¤Ê¤· */
        if (n == 0 || *s == 0) return;
        /*
         * Á´³Ñʸ»ú¤Î±¦È¾Ê¬¤«¤éʸ»ú¤òɽ¼¨¤¹¤ë¾ì¹ç¡¢
         * ½Å¤Ê¤Ã¤¿Ê¸»ú¤Îº¸Éôʬ¤ò¾Ãµî¡£
         * ɽ¼¨³«»Ï°ÌÃÖ¤¬º¸Ã¼¤Ç¤Ê¤¤¤È²¾Äê¡£
         */
        if (scr_aa[x] & KANJI2)
        {
                scr_cc[x - 1] = ' ';
                scr_aa[x - 1] &= KANJIC;
                x1 = x2 = x - 1;
        }
#endif
        /* Queue the attr/chars */
        for ( ; n; x++, s++, n--)
        {
#ifdef JP
                /* Æüìʸ»ú¤È¤·¤ÆMSB¤¬Î©¤Ã¤Æ¤¤¤ë²ÄǽÀ­¤¬¤¢¤ë */
                /* ¤½¤Î¾ì¹çattr¤ÎMSB¤âΩ¤Ã¤Æ¤¤¤ë¤Î¤Ç¤³¤ì¤Ç¼±Ê̤¹¤ë */
/* check */
                if (iskanji(*s) && !(a & 0x80))
                {
                        int nc1 = *s++;
                        int nc2 = *s;

                        int na1 = (a | KANJI1);
                        int na2 = (a | KANJI2);

                        if((--n == 0) || !nc2) break;
#ifdef USE_TRANSPARENCY
                        if(scr_aa[x++] == na1 && scr_aa[x] == na2 &&
                           scr_cc[x - 1] == nc1 && scr_cc[x] == nc2 &&
                           (scr_taa[x - 1] == 0) && (scr_taa[x]==0) &&
                           (scr_tcc[x - 1] == 0) && (scr_tcc[x]==0)    )
                                continue;
#else
                        if(scr_aa[x++] == na1 && scr_aa[x] == na2 &&
                           scr_cc[x - 1] == nc1 && scr_cc[x] == nc2) continue;
#endif
                        scr_aa[x - 1] = na1;
                        scr_aa[x] = na2;
                        scr_cc[x - 1] = nc1;
                        scr_cc[x] = nc2;

                        if(x1 < 0) x1 = x - 1;
                        x2 = x;
                }
                else
                {
#endif
                int oa = scr_aa[x];
                int oc = scr_cc[x];

#ifdef USE_TRANSPARENCY

                int ota = scr_taa[x];
                int otc = scr_tcc[x];

                /* Hack -- Ignore non-changes */
                if ((oa == a) && (oc == *s) && (ota == 0) && (otc == 0)) continue;

#else /* USE_TRANSPARENCY */

                /* Hack -- Ignore non-changes */
                if ((oa == a) && (oc == *s)) continue;

#endif /* USE_TRANSPARENCY */

                /* Save the "literal" information */
                scr_aa[x] = a;
                scr_cc[x] = *s;

#ifdef USE_TRANSPARENCY

                scr_taa[x] = 0;
                scr_tcc[x] = 0;

#endif /* USE_TRANSPARENCY */

                /* Note the "range" of window updates */
                if (x1 < 0) x1 = x;
                x2 = x;
#ifdef JP
        }
#endif
        }

#ifdef JP
        /*
         * Á´³Ñʸ»ú¤Îº¸È¾Ê¬¤Çɽ¼¨¤ò½ªÎ»¤¹¤ë¾ì¹ç¡¢
         * ½Å¤Ê¤Ã¤¿Ê¸»ú¤Î±¦Éôʬ¤ò¾Ãµî¡£
         * (¾ò·ïÄɲ᧥¿¥¤¥ë¤Î1ʸ»úÌܤǤʤ¤»ö¤ò³Î¤«¤á¤ë¤è¤¦¤Ë¡£)
         */
        {

                int w, h;
                Term_get_size(&w, &h);
                if (x != w && !(scr_aa[x] & 0x80) && (scr_aa[x] & KANJI2))
                {
                        scr_cc[x] = ' ';
                        scr_aa[x] &= KANJIC;
                        if (x1 < 0) x1 = x;
                        x2 = x;
                }
        }
#endif
        /* Expand the "change area" as needed */
        if (x1 >= 0)
        {
                /* Check for new min/max row info */
                if (y < Term->y1) Term->y1 = y;
                if (y > Term->y2) Term->y2 = y;

                /* Check for new min/max col info in this row */
                if (x1 < Term->x1[y]) Term->x1[y] = x1;
                if (x2 > Term->x2[y]) Term->x2[y] = x2;
        }
}



/*** Refresh routines ***/


/*
 * Flush a row of the current window (see "Term_fresh")
 *
 * Display text using "Term_pict()"
 */
static void Term_fresh_row_pict(int y, int x1, int x2)
{
        int x;

        byte *old_aa = Term->old->a[y];
        char *old_cc = Term->old->c[y];

        byte *scr_aa = Term->scr->a[y];
        char *scr_cc = Term->scr->c[y];

#ifdef USE_TRANSPARENCY

        byte *old_taa = Term->old->ta[y];
        char *old_tcc = Term->old->tc[y];

        byte *scr_taa = Term->scr->ta[y];
        char *scr_tcc = Term->scr->tc[y];

        byte ota;
        char otc;

        byte nta;
        char ntc;

#endif /* USE_TRANSPARENCY */


        /* Pending length */
        int fn = 0;

        /* Pending start */
        int fx = 0;

        byte oa;
        char oc;

        byte na;
        char nc;

#ifdef JP
        /* Á´³Ñʸ»ú¤Î£²¥Ð¥¤¥ÈÌܤ«¤É¤¦¤« */
        int kanji = 0;
#endif
        /* Scan "modified" columns */
        for (x = x1; x <= x2; x++)
        {
                /* See what is currently here */
                oa = old_aa[x];
                oc = old_cc[x];

                /* See what is desired there */
                na = scr_aa[x];
                nc = scr_cc[x];

#ifdef JP
                if (kanji)
                {
                        /* Á´³Ñʸ»ú£²¥Ð¥¤¥ÈÌÜ */
                        kanji = 0;
                        old_aa[x] = na;
                        old_cc[x] = nc;
                        fn++;
                        continue;
                }
                /* Æüìʸ»ú¤È¤·¤ÆMSB¤¬Î©¤Ã¤Æ¤¤¤ë²ÄǽÀ­¤¬¤¢¤ë */
                /* ¤½¤Î¾ì¹çattr¤ÎMSB¤âΩ¤Ã¤Æ¤¤¤ë¤Î¤Ç¤³¤ì¤Ç¼±Ê̤¹¤ë */
/* check */
                kanji = (iskanji(nc) && !(na & 0x80));
#endif
#ifdef USE_TRANSPARENCY

                ota = old_taa[x];
                otc = old_tcc[x];

                nta = scr_taa[x];
                ntc = scr_tcc[x];

                /* Handle unchanged grids */
#ifdef JP
                if ((na == oa) && (nc == oc) && (nta == ota) && (ntc == otc)
                    &&(!kanji || (scr_aa[x + 1] == old_aa[x + 1] &&
                                  scr_cc[x + 1] == old_cc[x + 1] &&
                                  scr_taa[x + 1] == old_taa[x + 1] &&
                                  scr_tcc[x + 1] == old_tcc[x + 1])))
#else
                if ((na == oa) && (nc == oc) && (nta == ota) && (ntc == otc))
#endif


#else /* USE_TRANSPARENCY */

                /* Handle unchanged grids */
#ifdef JP
                if ((na == oa) && (nc == oc) &&
                    (!kanji || (scr_aa[x + 1] == old_aa[x + 1] &&
                                scr_cc[x + 1] == old_cc[x + 1])))
#else
                if ((na == oa) && (nc == oc))
#endif


#endif /* USE_TRANSPARENCY */
                {
                        /* Flush */
                        if (fn)
                        {
                                /* Draw pending attr/char pairs */
#ifdef USE_TRANSPARENCY
                                (void)((*Term->pict_hook)(fx, y, fn,
                                       &scr_aa[fx], &scr_cc[fx],&scr_taa[fx], &scr_tcc[fx]));
#else /* USE_TRANSPARENCY */
                                (void)((*Term->pict_hook)(fx, y, fn, &scr_aa[fx], &scr_cc[fx]));
#endif /* USE_TRANSPARENCY */

                                /* Forget */
                                fn = 0;
                        }

#ifdef JP
                        /* Á´³Ñʸ»ú¤Î»þ¤ÏºÆ³«°ÌÃ֤ϡܣ± */
                        if(kanji)
                        {
                                x++;
                                fx++;
                                kanji = 0;
                        }
#endif
                        /* Skip */
                        continue;
                }
                /* Save new contents */
                old_aa[x] = na;
                old_cc[x] = nc;

#ifdef USE_TRANSPARENCY
                old_taa[x] = nta;
                old_tcc[x] = ntc;
#endif /* USE_TRANSPARENCY */

                /* Restart and Advance */
                if (fn++ == 0) fx = x;
        }

        /* Flush */
        if (fn)
        {
                /* Draw pending attr/char pairs */
#ifdef USE_TRANSPARENCY
                (void)((*Term->pict_hook)(fx, y, fn,
                        &scr_aa[fx], &scr_cc[fx], &scr_taa[fx], &scr_tcc[fx]));
#else /* USE_TRANSPARENCY */
                (void)((*Term->pict_hook)(fx, y, fn, &scr_aa[fx], &scr_cc[fx]));
#endif /* USE_TRANSPARENCY */
        }
}



/*
 * Flush a row of the current window (see "Term_fresh")
 *
 * Display text using "Term_text()" and "Term_wipe()",
 * but use "Term_pict()" for high-bit attr/char pairs
 */
static void Term_fresh_row_both(int y, int x1, int x2)
{
        int x;

        byte *old_aa = Term->old->a[y];
        char *old_cc = Term->old->c[y];

        byte *scr_aa = Term->scr->a[y];
        char *scr_cc = Term->scr->c[y];

#ifdef USE_TRANSPARENCY
        byte *old_taa = Term->old->ta[y];
        char *old_tcc = Term->old->tc[y];
        byte *scr_taa = Term->scr->ta[y];
        char *scr_tcc = Term->scr->tc[y];

        byte ota;
        char otc;
        byte nta;
        char ntc;
#endif /* USE_TRANSPARENCY */

        /* The "always_text" flag */
        int always_text = Term->always_text;

        /* Pending length */
        int fn = 0;

        /* Pending start */
        int fx = 0;

        /* Pending attr */
        byte fa = Term->attr_blank;

        byte oa;
        char oc;

        byte na;
        char nc;

#ifdef JP
        /* Á´³Ñʸ»ú¤Î£²¥Ð¥¤¥ÈÌܤ«¤É¤¦¤« */
        int kanji = 0;
#endif
        /* Scan "modified" columns */
        for (x = x1; x <= x2; x++)
        {
                /* See what is currently here */
                oa = old_aa[x];
                oc = old_cc[x];

                /* See what is desired there */
                na = scr_aa[x];
                nc = scr_cc[x];

#ifdef JP
                if (kanji)
                {
                        /* Á´³Ñʸ»ú£²¥Ð¥¤¥ÈÌÜ */
                        kanji = 0;
                        old_aa[x] = na;
                        old_cc[x] = nc;
                        fn++;
                        continue;
                }
                /* Æüìʸ»ú¤È¤·¤ÆMSB¤¬Î©¤Ã¤Æ¤¤¤ë²ÄǽÀ­¤¬¤¢¤ë */
                /* ¤½¤Î¾ì¹çattr¤ÎMSB¤âΩ¤Ã¤Æ¤¤¤ë¤Î¤Ç¤³¤ì¤Ç¼±Ê̤¹¤ë */
/* check */
/*              kanji = (iskanji(nc));  */
                kanji = (iskanji(nc) && !(na & 0x80));
#endif
#ifdef USE_TRANSPARENCY

                ota = old_taa[x];
                otc = old_tcc[x];

                nta = scr_taa[x];
                ntc = scr_tcc[x];

                /* Handle unchanged grids */
#ifdef JP
                if ((na == oa) && (nc == oc) && (nta == ota) && (ntc == otc)&&
                    (!kanji || (scr_aa[x + 1] == old_aa[x + 1] &&
                                scr_cc[x + 1] == old_cc[x + 1] &&
                                scr_taa[x + 1] == old_taa[x + 1] &&
                                scr_tcc[x + 1] == old_tcc[x + 1])))
#else
                if ((na == oa) && (nc == oc) && (nta == ota) && (ntc == otc))
#endif


#else /* USE_TRANSPARENCY */

                /* Handle unchanged grids */
#ifdef JP
                if ((na == oa) && (nc == oc) &&
                    (!kanji || (scr_aa[x + 1] == old_aa[x + 1] &&
                                scr_cc[x + 1] == old_cc[x + 1])))
#else
                if ((na == oa) && (nc == oc))
#endif


#endif /* USE_TRANSPARENCY */

                {
                        /* Flush */
                        if (fn)
                        {
                                /* Draw pending chars (normal) */
                                if (fa || always_text)
                                {
#ifdef CHUUKEI
                        send_text_to_chuukei_server(fx, y, fn, fa, &scr_cc[fx]);
#endif
                                        (void)((*Term->text_hook)(fx, y, fn, fa, &scr_cc[fx]));
                                }

                                /* Draw pending chars (black) */
                                else
                                {
#ifdef CHUUKEI
                        send_wipe_to_chuukei_server(fx, y, fn);
#endif
                                        (void)((*Term->wipe_hook)(fx, y, fn));
                                }

                                /* Forget */
                                fn = 0;
                        }

#ifdef JP
                        /* Á´³Ñʸ»ú¤Î»þ¤ÏºÆ³«°ÌÃ֤ϡܣ± */
                        if(kanji)
                        {
                                x++;
                                fx++;
                                kanji = 0;
                        }
#endif
                        /* Skip */
                        continue;
                }

                /* Save new contents */
                old_aa[x] = na;
                old_cc[x] = nc;

#ifdef USE_TRANSPARENCY

                old_taa[x] = nta;
                old_tcc[x] = ntc;

#endif /* USE_TRANSPARENCY */

                /* 2nd byte of bigtile */
                if (na == 255) continue;

                /* Handle high-bit attr/chars */
                if ((na & 0x80) && (nc & 0x80))
                {
                        /* Flush */
                        if (fn)
                        {
                                /* Draw pending chars (normal) */
                                if (fa || always_text)
                                {
#ifdef CHUUKEI
                        send_text_to_chuukei_server(fx, y, fn, fa, &scr_cc[fx]);
#endif
                                        (void)((*Term->text_hook)(fx, y, fn, fa, &scr_cc[fx]));
                                }

                                /* Draw pending chars (black) */
                                else
                                {
#ifdef CHUUKEI
                        send_wipe_to_chuukei_server(fx, y, fn);
#endif
                                        (void)((*Term->wipe_hook)(fx, y, fn));
                                }

                                /* Forget */
                                fn = 0;
                        }

#ifdef USE_TRANSPARENCY

                        /* Hack -- Draw the special attr/char pair */
                        (void)((*Term->pict_hook)(x, y, 1, &na, &nc, &nta, &ntc));

#else /* USE_TRANSPARENCY */

                        /* Hack -- Draw the special attr/char pair */
                        (void)((*Term->pict_hook)(x, y, 1, &na, &nc));

#endif /* USE_TRANSPARENCY */

                        /* Skip */
                        continue;
                }

                /* Notice new color */
#ifdef JP
                if (fa != (na & KANJIC))
#else
                if (fa != na)
#endif

                {
                        /* Flush */
                        if (fn)
                        {
                                /* Draw the pending chars */
                                if (fa || always_text)
                                {
#ifdef CHUUKEI
                        send_text_to_chuukei_server(fx, y, fn, fa, &scr_cc[fx]);
#endif
                                        (void)((*Term->text_hook)(fx, y, fn, fa, &scr_cc[fx]));
                                }

                                /* Hack -- Erase "leading" spaces */
                                else
                                {
#ifdef CHUUKEI
                        send_wipe_to_chuukei_server(fx, y, fn);
#endif
                                        (void)((*Term->wipe_hook)(fx, y, fn));
                                }

                                /* Forget */
                                fn = 0;
                        }

                        /* Save the new color */
#ifdef JP
                        fa = (na & KANJIC);
#else
                        fa = na;
#endif

                }

                /* Restart and Advance */
                if (fn++ == 0) fx = x;
        }

        /* Flush */
        if (fn)
        {
                /* Draw pending chars (normal) */
                if (fa || always_text)
                {
#ifdef CHUUKEI
                        send_text_to_chuukei_server(fx, y, fn, fa, &scr_cc[fx]);
#endif
                        (void)((*Term->text_hook)(fx, y, fn, fa, &scr_cc[fx]));
                }

                /* Draw pending chars (black) */
                else
                {
#ifdef CHUUKEI
                        send_wipe_to_chuukei_server(fx, y, fn);
#endif
                        (void)((*Term->wipe_hook)(fx, y, fn));
                }
        }
}


/*
 * Flush a row of the current window (see "Term_fresh")
 *
 * Display text using "Term_text()" and "Term_wipe()"
 */
static void Term_fresh_row_text(int y, int x1, int x2)
{
        int x;

        byte *old_aa = Term->old->a[y];
        char *old_cc = Term->old->c[y];

        byte *scr_aa = Term->scr->a[y];
        char *scr_cc = Term->scr->c[y];

        /* The "always_text" flag */
        int always_text = Term->always_text;

        /* Pending length */
        int fn = 0;

        /* Pending start */
        int fx = 0;

        /* Pending attr */
        byte fa = Term->attr_blank;

        byte oa;
        char oc;

        byte na;
        char nc;

#ifdef JP
        /* Á´³Ñʸ»ú¤Î£²¥Ð¥¤¥ÈÌܤ«¤É¤¦¤« */
        int kanji = 0;

        for (x = 0; x < x1; x++)
                if (!(old_aa[x] & 0x80) && iskanji(old_cc[x]))
                {
                        if (x == x1 - 1)
                        {
                                x1--;
                                break;
                        }
                        else
                                x++;
                }
#endif
        /* Scan "modified" columns */
        for (x = x1; x <= x2; x++)
        {
                /* See what is currently here */
                oa = old_aa[x];
                oc = old_cc[x];

                /* See what is desired there */
                na = scr_aa[x];
                nc = scr_cc[x];

#ifdef JP
                if (kanji)
                {
                        /* Á´³Ñʸ»ú£²¥Ð¥¤¥ÈÌÜ */
                        kanji = 0;
                        old_aa[x] = na;
                        old_cc[x] = nc;
                        fn++;
                        continue;
                }
                /* Æüìʸ»ú¤È¤·¤ÆMSB¤¬Î©¤Ã¤Æ¤¤¤ë²ÄǽÀ­¤¬¤¢¤ë */
                /* ¤½¤Î¾ì¹çattr¤ÎMSB¤âΩ¤Ã¤Æ¤¤¤ë¤Î¤Ç¤³¤ì¤Ç¼±Ê̤¹¤ë */
/* check */
                kanji = (iskanji(nc) && !(na & 0x80));
#endif
                /* Handle unchanged grids */
#ifdef JP
                if ((na == oa) && (nc == oc) &&
                    (!kanji || (scr_aa[x + 1] == old_aa[x + 1] &&
                                scr_cc[x + 1] == old_cc[x + 1])))
#else
                if ((na == oa) && (nc == oc))
#endif

                {
                        /* Flush */
                        if (fn)
                        {
                                /* Draw pending chars (normal) */
                                if (fa || always_text)
                                {
#ifdef CHUUKEI
                        send_text_to_chuukei_server(fx, y, fn, fa, &scr_cc[fx]);
#endif
                                        (void)((*Term->text_hook)(fx, y, fn, fa, &scr_cc[fx]));
                                }

                                /* Draw pending chars (black) */
                                else
                                {
#ifdef CHUUKEI
                        send_wipe_to_chuukei_server(fx, y, fn);
#endif
                                        (void)((*Term->wipe_hook)(fx, y, fn));
                                }

                                /* Forget */
                                fn = 0;
                        }

#ifdef JP
                        /* Á´³Ñʸ»ú¤Î»þ¤ÏºÆ³«°ÌÃ֤ϡܣ± */
                        if(kanji)
                        {
                                x++;
                                fx++;
                                kanji = 0;
                        }
#endif
                        /* Skip */
                        continue;
                }

                /* Save new contents */
                old_aa[x] = na;
                old_cc[x] = nc;

                /* Notice new color */
#ifdef JP
                if (fa != (na & KANJIC))
#else
                if (fa != na)
#endif

                {
                        /* Flush */
                        if (fn)
                        {
                                /* Draw the pending chars */
                                if (fa || always_text)
                                {
#ifdef CHUUKEI
                        send_text_to_chuukei_server(fx, y, fn, fa, &scr_cc[fx]);
#endif
                                        (void)((*Term->text_hook)(fx, y, fn, fa, &scr_cc[fx]));
                                }

                                /* Hack -- Erase "leading" spaces */
                                else
                                {
#ifdef CHUUKEI
                        send_wipe_to_chuukei_server(fx, y, fn);
#endif
                                        (void)((*Term->wipe_hook)(fx, y, fn));
                                }

                                /* Forget */
                                fn = 0;
                        }

                        /* Save the new color */
#ifdef JP
                        fa = (na & KANJIC);
#else
                        fa = na;
#endif

                }

                /* Restart and Advance */
                if (fn++ == 0) fx = x;
        }

        /* Flush */
        if (fn)
        {
                /* Draw pending chars (normal) */
                if (fa || always_text)
                {
#ifdef CHUUKEI
                        send_text_to_chuukei_server(fx, y, fn, fa, &scr_cc[fx]);
#endif
                        (void)((*Term->text_hook)(fx, y, fn, fa, &scr_cc[fx]));
                }

                /* Draw pending chars (black) */
                else
                {
#ifdef CHUUKEI
                        send_wipe_to_chuukei_server(fx, y, fn);
#endif
                        (void)((*Term->wipe_hook)(fx, y, fn));
                }
        }
}





/*
 * Actually perform all requested changes to the window
 *
 * If absolutely nothing has changed, not even temporarily, or if the
 * current "Term" is not mapped, then this function will return 1 and
 * do absolutely nothing.
 *
 * Note that when "soft_cursor" is true, we erase the cursor (if needed)
 * whenever anything has changed, and redraw it (if needed) after all of
 * the screen updates are complete.  This will induce a small amount of
 * "cursor flicker" but only when the screen has been updated.  If the
 * screen is updated and then restored, you may still get this flicker.
 *
 * When "soft_cursor" is not true, we make the cursor invisible before
 * doing anything else if it is supposed to be invisible by the time we
 * are done, and we make it visible after moving it to its final location
 * after all of the screen updates are complete.
 *
 * Note that "Term_xtra(TERM_XTRA_CLEAR,0)" must erase the entire screen,
 * including the cursor, if needed, and may place the cursor anywhere.
 *
 * Note that "Term_xtra(TERM_XTRA_FROSH,y)" will be always be called
 * after any row "y" has been "flushed", unless the "Term->never_frosh"
 * flag is set, and "Term_xtra(TERM_XTRA_FRESH,0)" will be called after
 * all of the rows have been "flushed".
 *
 * Note the use of three different functions to handle the actual flush,
 * based on the settings of the "Term->always_pict" and "Term->higher_pict"
 * flags (see below).
 *
 * The three helper functions (above) work by collecting similar adjacent
 * grids into stripes, and then sending each stripe to "Term->pict_hook",
 * "Term->text_hook", or "Term->wipe_hook", based on the settings of the
 * "Term->always_pict" and "Term->higher_pict" flags, which select which
 * of the helper functions to call to flush each row.
 *
 * The helper functions currently "skip" any grids which already contain
 * the desired contents.  This may or may not be the best method, especially
 * when the desired content fits nicely into the current stripe.  For example,
 * it might be better to go ahead and queue them while allowed, but keep a
 * count of the "trailing skipables", then, when time to flush, or when a
 * "non skippable" is found, force a flush if there are too many skippables.
 *
 * Perhaps an "initialization" stage, where the "text" (and "attr")
 * buffers are "filled" with information, converting "blanks" into
 * a convenient representation, and marking "skips" with "zero chars",
 * and then some "processing" is done to determine which chars to skip.
 *
 * Currently, the helper functions are optimal for systems which prefer
 * to "print a char + move a char + print a char" to "print three chars",
 * and for applications that do a lot of "detailed" color printing.
 *
 * In the two "queue" functions, total "non-changes" are "pre-skipped".
 * The helper functions must also handle situations in which the contents
 * of a grid are changed, but then changed back to the original value,
 * and situations in which two grids in the same row are changed, but
 * the grids between them are unchanged.
 *
 * If the "Term->always_pict" flag is set, then "Term_fresh_row_pict()"
 * will be used instead of "Term_fresh_row_text()".  This allows all the
 * modified grids to be collected into stripes of attr/char pairs, which
 * are then sent to the "Term->pict_hook" hook, which can draw these pairs
 * in whatever way it would like.
 *
 * If the "Term->higher_pict" flag is set, then "Term_fresh_row_both()"
 * will be used instead of "Term_fresh_row_text()".  This allows all the
 * "special" attr/char pairs (in which both the attr and char have the
 * high-bit set) to be sent (one pair at a time) to the "Term->pict_hook"
 * hook, which can draw these pairs in whatever way it would like.
 *
 * Normally, the "Term_wipe()" function is used only to display "blanks"
 * that were induced by "Term_clear()" or "Term_erase()", and then only
 * if the "attr_blank" and "char_blank" fields have not been redefined
 * to use "white space" instead of the default "black space".  Actually,
 * the "Term_wipe()" function is used to display all "black" text, such
 * as the default "spaces" created by "Term_clear()" and "Term_erase()".
 *
 * Note that the "Term->always_text" flag will disable the use of the
 * "Term_wipe()" function hook entirely, and force all text, even text
 * drawn in the color "black", to be explicitly drawn.  This is useful
 * for machines which implement "Term_wipe()" by just drawing spaces.
 *
 * Note that the "Term->always_pict" flag will disable the use of the
 * "Term_wipe()" function entirely, and force everything, even text
 * drawn in the attr "black", to be explicitly drawn.
 *
 * Note that if no "black" text is ever drawn, and if "attr_blank" is
 * not "zero", then the "Term_wipe" hook will never be used, even if
 * the "Term->always_text" flag is not set.
 *
 * This function does nothing unless the "Term" is "mapped", which allows
 * certain systems to optimize the handling of "closed" windows.
 *
 * On systems with a "soft" cursor, we must explicitly erase the cursor
 * before flushing the output, if needed, to prevent a "jumpy" refresh.
 * The actual method for this is horrible, but there is very little that
 * we can do to simplify it efficiently.  XXX XXX XXX
 *
 * On systems with a "hard" cursor, we will "hide" the cursor before
 * flushing the output, if needed, to avoid a "flickery" refresh.  It
 * would be nice to *always* hide the cursor during the refresh, but
 * this might be expensive (and/or ugly) on some machines.
 *
 * The "Term->icky_corner" flag is used to avoid calling "Term_wipe()"
 * or "Term_pict()" or "Term_text()" on the bottom right corner of the
 * window, which might induce "scrolling" or other nasty stuff on old
 * dumb terminals.  This flag is handled very efficiently.  We assume
 * that the "Term_curs()" call will prevent placing the cursor in the
 * corner, if needed, though I doubt such placement is ever a problem.
 * Currently, the use of "Term->icky_corner" and "Term->soft_cursor"
 * together may result in undefined behavior.
 */
errr Term_fresh(void)
{
        int x, y;

        int w = Term->wid;
        int h = Term->hgt;

        int y1 = Term->y1;
        int y2 = Term->y2;

        term_win *old = Term->old;
        term_win *scr = Term->scr;


        /* Do nothing unless "mapped" */
        if (!Term->mapped_flag) return (1);


        /* Trivial Refresh */
        if ((y1 > y2) &&
            (scr->cu == old->cu) &&
            (scr->cv == old->cv) &&
            (scr->cx == old->cx) &&
            (scr->cy == old->cy) &&
            !(Term->total_erase))
        {
                /* Nothing */
                return (1);
        }


        /* Paranoia -- use "fake" hooks to prevent core dumps */
        if (!Term->curs_hook) Term->curs_hook = Term_curs_hack;
        if (!Term->wipe_hook) Term->wipe_hook = Term_wipe_hack;
        if (!Term->text_hook) Term->text_hook = Term_text_hack;
        if (!Term->pict_hook) Term->pict_hook = Term_pict_hack;


        /* Handle "total erase" */
        if (Term->total_erase)
        {
                byte na = Term->attr_blank;
                char nc = Term->char_blank;

                /* Physically erase the entire window */
                Term_xtra(TERM_XTRA_CLEAR, 0);

                /* Hack -- clear all "cursor" data */
                old->cv = old->cu = old->cx = old->cy = 0;

                /* Wipe each row */
                for (y = 0; y < h; y++)
                {
                        byte *aa = old->a[y];
                        char *cc = old->c[y];

#ifdef USE_TRANSPARENCY

                        byte *taa = old->ta[y];
                        char *tcc = old->tc[y];

#endif /* USE_TRANSPARENCY */


                        /* Wipe each column */
                        for (x = 0; x < w; x++)
                        {
                                /* Wipe each grid */
                                *aa++ = na;
                                *cc++ = nc;

#ifdef USE_TRANSPARENCY

                                *taa++ = na;
                                *tcc++ = nc;

#endif /* USE_TRANSPARENCY */

                        }
                }

                /* Redraw every row */
                Term->y1 = y1 = 0;
                Term->y2 = y2 = h - 1;

                /* Redraw every column */
                for (y = 0; y < h; y++)
                {
                        Term->x1[y] = 0;
                        Term->x2[y] = w - 1;
                }

                /* Forget "total erase" */
                Term->total_erase = FALSE;
        }


        /* Cursor update -- Erase old Cursor */
        if (Term->soft_cursor)
        {
                /* Cursor was visible */
                if (!old->cu && old->cv)
                {
                        int tx = old->cx;
                        int ty = old->cy;

                        byte *old_aa = old->a[ty];
                        char *old_cc = old->c[ty];

                        byte oa = old_aa[tx];
                        char oc = old_cc[tx];

#ifdef USE_TRANSPARENCY

                        byte *old_taa = old->ta[ty];
                        char *old_tcc = old->tc[ty];

                        byte ota = old_taa[tx];
                        char otc = old_tcc[tx];

#endif /* USE_TRANSPARENCY */

                        /* Hack -- use "Term_pict()" always */
                        if (Term->always_pict)
                        {
#ifdef USE_TRANSPARENCY
                                (void)((*Term->pict_hook)(tx, ty, 1, &oa, &oc, &ota, &otc));
#else /* USE_TRANSPARENCY */
                                (void)((*Term->pict_hook)(tx, ty, 1, &oa, &oc));
#endif /* USE_TRANSPARENCY */
                        }

                        /* Hack -- use "Term_pict()" sometimes */
                        else if (Term->higher_pict && (oa & 0x80) && (oc & 0x80))
                        {
#ifdef USE_TRANSPARENCY
                                (void)((*Term->pict_hook)(tx, ty, 1, &oa, &oc, &ota, &otc));
#else /* USE_TRANSPARENCY */
                                (void)((*Term->pict_hook)(tx, ty, 1, &oa, &oc));
#endif /* USE_TRANSPARENCY */
                        }

                        /* Hack -- restore the actual character */
                        else if (oa || Term->always_text)
                        {

#ifdef CHUUKEI
                                send_text_to_chuukei_server(tx, ty, 1, oa, &oc);
#endif
#ifdef JP
                                if (tx + 1 < Term->wid && !(old_aa[tx] & 0x80) && (iskanji(old_cc[tx])))
                                        /* Redraw a Kanji */
                                        (void)((*Term->text_hook)(tx, ty, 2, oa, &old_cc[tx]));
                                else
#endif
                                        (void)((*Term->text_hook)(tx, ty, 1, oa, &oc));
                        }

                        /* Hack -- erase the grid */
                        else
                        {
#ifdef CHUUKEI
                        send_wipe_to_chuukei_server(tx, ty, 1);
#endif
                                (void)((*Term->wipe_hook)(tx, ty, 1));
                        }
                }
        }

        /* Cursor Update -- Erase old Cursor */
        else
        {
                /* Cursor will be invisible */
                if (scr->cu || !scr->cv)
                {
                        /* Make the cursor invisible */
                        Term_xtra(TERM_XTRA_SHAPE, 0);
                }
        }


        /* Something to update */
        if (y1 <= y2)
        {
                /* Handle "icky corner" */
                if (Term->icky_corner)
                {
                        /* Avoid the corner */
                        if (y2 >= h - 1)
                        {
                                /* Avoid the corner */
                                if (Term->x2[h - 1] > w - 2)
                                {
                                        /* Avoid the corner */
                                        Term->x2[h - 1] = w - 2;
                                }
                        }
                }


                /* Scan the "modified" rows */
                for (y = y1; y <= y2; ++y)
                {
                        int x1 = Term->x1[y];
                        int x2 = Term->x2[y];

                        /* Flush each "modified" row */
                        if (x1 <= x2)
                        {
                                /* Always use "Term_pict()" */
                                if (Term->always_pict)
                                {
                                        /* Flush the row */
                                        Term_fresh_row_pict(y, x1, x2);
                                }

                                /* Sometimes use "Term_pict()" */
                                else if (Term->higher_pict)
                                {
                                        /* Flush the row */
                                        Term_fresh_row_both(y, x1, x2);
                                }

                                /* Never use "Term_pict()" */
                                else
                                {
                                        /* Flush the row */
                                        Term_fresh_row_text(y, x1, x2);
                                }

                                /* This row is all done */
                                Term->x1[y] = w;
                                Term->x2[y] = 0;

                                /* Hack -- Flush that row (if allowed) */
                                if (!Term->never_frosh) Term_xtra(TERM_XTRA_FROSH, y);
                        }
                }

                /* No rows are invalid */
                Term->y1 = h;
                Term->y2 = 0;
        }


        /* Cursor update -- Show new Cursor */
        if (Term->soft_cursor)
        {
                /* Draw the cursor */
                if (!scr->cu && scr->cv)
                {
#ifdef CHUUKEI
                  send_curs_to_chuukei_server(scr->cx, scr->cy);
#endif
                        /* Call the cursor display routine */
                        (void)((*Term->curs_hook)(scr->cx, scr->cy));
                }
        }

        /* Cursor Update -- Show new Cursor */
        else
        {
                /* The cursor is useless, hide it */
                if (scr->cu)
                {
#ifdef CHUUKEI
                  send_curs_to_chuukei_server(w - 1, scr->cy);
#endif
                        /* Paranoia -- Put the cursor NEAR where it belongs */
                        (void)((*Term->curs_hook)(w - 1, scr->cy));

                        /* Make the cursor invisible */
                        /* Term_xtra(TERM_XTRA_SHAPE, 0); */
                }

                /* The cursor is invisible, hide it */
                else if (!scr->cv)
                {
#ifdef CHUUKEI
                  send_curs_to_chuukei_server(scr->cx, scr->cy);
#endif
                        /* Paranoia -- Put the cursor where it belongs */
                        (void)((*Term->curs_hook)(scr->cx, scr->cy));

                        /* Make the cursor invisible */
                        /* Term_xtra(TERM_XTRA_SHAPE, 0); */
                }

                /* The cursor is visible, display it correctly */
                else
                {
#ifdef CHUUKEI
                  send_curs_to_chuukei_server(scr->cx, scr->cy);
#endif
                        /* Put the cursor where it belongs */
                        (void)((*Term->curs_hook)(scr->cx, scr->cy));

                        /* Make the cursor visible */
                        Term_xtra(TERM_XTRA_SHAPE, 1);
                }
        }


        /* Save the "cursor state" */
        old->cu = scr->cu;
        old->cv = scr->cv;
        old->cx = scr->cx;
        old->cy = scr->cy;


        /* Actually flush the output */
        Term_xtra(TERM_XTRA_FRESH, 0);


        /* Success */
        return (0);
}



/*** Output routines ***/


/*
 * Set the cursor visibility
 */
errr Term_set_cursor(int v)
{
        /* Already done */
        if (Term->scr->cv == v) return (1);

        /* Change */
        Term->scr->cv = v;

        /* Success */
        return (0);
}


/*
 * Place the cursor at a given location
 *
 * Note -- "illegal" requests do not move the cursor.
 */
errr Term_gotoxy(int x, int y)
{
        int w = Term->wid;
        int h = Term->hgt;

        /* Verify */
        if ((x < 0) || (x >= w)) return (-1);
        if ((y < 0) || (y >= h)) return (-1);

        /* Remember the cursor */
        Term->scr->cx = x;
        Term->scr->cy = y;

        /* The cursor is not useless */
        Term->scr->cu = 0;

        /* Success */
        return (0);
}


/*
 * At a given location, place an attr/char
 * Do not change the cursor position
 * No visual changes until "Term_fresh()".
 */
errr Term_draw(int x, int y, byte a, char c)
{
        int w = Term->wid;
        int h = Term->hgt;

        /* Verify location */
        if ((x < 0) || (x >= w)) return (-1);
        if ((y < 0) || (y >= h)) return (-1);

        /* Paranoia -- illegal char */
        if (!c) return (-2);

        /* Queue it for later */
#ifdef USE_TRANSPARENCY
        Term_queue_char(x, y, a, c, 0, 0);
#else /* USE_TRANSPARENCY */
        Term_queue_char(x, y, a, c);
#endif /* USE_TRANSPARENCY */

        /* Success */
        return (0);
}


/*
 * Using the given attr, add the given char at the cursor.
 *
 * We return "-2" if the character is "illegal". XXX XXX
 *
 * We return "-1" if the cursor is currently unusable.
 *
 * We queue the given attr/char for display at the current
 * cursor location, and advance the cursor to the right,
 * marking it as unuable and returning "1" if it leaves
 * the screen, and otherwise returning "0".
 *
 * So when this function, or the following one, return a
 * positive value, future calls to either function will
 * return negative ones.
 */
errr Term_addch(byte a, char c)
{
        int w = Term->wid;

        /* Handle "unusable" cursor */
        if (Term->scr->cu) return (-1);

        /* Paranoia -- no illegal chars */
        if (!c) return (-2);

        /* Queue the given character for display */
#ifdef USE_TRANSPARENCY
        Term_queue_char(Term->scr->cx, Term->scr->cy, a, c, 0, 0);
#else /* USE_TRANSPARENCY */
        Term_queue_char(Term->scr->cx, Term->scr->cy, a, c);
#endif /* USE_TRANSPARENCY */

        /* Advance the cursor */
        Term->scr->cx++;

        /* Success */
        if (Term->scr->cx < w) return (0);

        /* Note "Useless" cursor */
        Term->scr->cu = 1;

        /* Note "Useless" cursor */
        return (1);
}


/*
 * At the current location, using an attr, add a string
 *
 * We also take a length "n", using negative values to imply
 * the largest possible value, and then we use the minimum of
 * this length and the "actual" length of the string as the
 * actual number of characters to attempt to display, never
 * displaying more characters than will actually fit, since
 * we do NOT attempt to "wrap" the cursor at the screen edge.
 *
 * We return "-1" if the cursor is currently unusable.
 * We return "N" if we were "only" able to write "N" chars,
 * even if all of the given characters fit on the screen,
 * and mark the cursor as unusable for future attempts.
 *
 * So when this function, or the preceding one, return a
 * positive value, future calls to either function will
 * return negative ones.
 */
errr Term_addstr(int n, byte a, cptr s)
{
        int k;

        int w = Term->wid;

        errr res = 0;

        /* Handle "unusable" cursor */
        if (Term->scr->cu) return (-1);

        /* Obtain maximal length */
        k = (n < 0) ? (w + 1) : n;

        /* Obtain the usable string length */
        for (n = 0; (n < k) && s[n]; n++) /* loop */;

        /* React to reaching the edge of the screen */
        if (Term->scr->cx + n >= w) res = n = w - Term->scr->cx;

        /* Queue the first "n" characters for display */
        Term_queue_chars(Term->scr->cx, Term->scr->cy, n, a, s);

        /* Advance the cursor */
        Term->scr->cx += n;

        /* Hack -- Notice "Useless" cursor */
        if (res) Term->scr->cu = 1;

        /* Success (usually) */
        return (res);
}


/*
 * Move to a location and, using an attr, add a char
 */
errr Term_putch(int x, int y, byte a, char c)
{
        errr res;

        /* Move first */
        if ((res = Term_gotoxy(x, y)) != 0) return (res);

        /* Then add the char */
        if ((res = Term_addch(a, c)) != 0) return (res);

        /* Success */
        return (0);
}


/*
 * Move to a location and, using an attr, add a string
 */
errr Term_putstr(int x, int y, int n, byte a, cptr s)
{
        errr res;

        /* Move first */
        if ((res = Term_gotoxy(x, y)) != 0) return (res);

        /* Then add the string */
        if ((res = Term_addstr(n, a, s)) != 0) return (res);

        /* Success */
        return (0);
}

#ifdef JP
/*
 * Move to a location and, using an attr, add a string vertically
 */
errr Term_putstr_v(int x, int y, int n, byte a, cptr s)
{
        errr res;
        int i;
        int y0 = y;


        for (i = 0; i < n && s[i] != 0; i++)
        {
          /* Move first */
          if ((res = Term_gotoxy(x, y0)) != 0) return (res);

          if (iskanji(s[i]))
          {
            if ((res = Term_addstr(2, a, &s[i])) != 0) return (res);
            i++;
            y0++;
            if (s[i] == 0) break;
          } else {
            if ((res = Term_addstr(1, a, &s[i])) != 0) return (res);
            y0++;
          }
        }

        /* Success */
        return (0);
}
#endif

/*
 * Place cursor at (x,y), and clear the next "n" chars
 */
errr Term_erase(int x, int y, int n)
{
        int i;

        int w = Term->wid;
        /* int h = Term->hgt; */

        int x1 = -1;
        int x2 = -1;

        int na = Term->attr_blank;
        int nc = Term->char_blank;

        byte *scr_aa;
        char *scr_cc;

#ifdef USE_TRANSPARENCY
        byte *scr_taa;
        char *scr_tcc;
#endif /* USE_TRANSPARENCY */

        /* Place cursor */
        if (Term_gotoxy(x, y)) return (-1);

        /* Force legal size */
        if (x + n > w) n = w - x;

        /* Fast access */
        scr_aa = Term->scr->a[y];
        scr_cc = Term->scr->c[y];

#ifdef USE_TRANSPARENCY
        scr_taa = Term->scr->ta[y];
        scr_tcc = Term->scr->tc[y];
#endif /* USE_TRANSPARENCY */

#ifdef JP
        /*
         * Á´³Ñʸ»ú¤Î±¦È¾Ê¬¤«¤éʸ»ú¤òɽ¼¨¤¹¤ë¾ì¹ç¡¢
         * ½Å¤Ê¤Ã¤¿Ê¸»ú¤Îº¸Éôʬ¤ò¾Ãµî¡£
         */
        if (n > 0 && (scr_aa[x] & KANJI2))
#else
        if (n > 0 && (byte)scr_cc[x] == 255 && scr_aa[x] == 255)
#endif
        {
                x--;
                n++;
        }

        /* Scan every column */
        for (i = 0; i < n; i++, x++)
        {
                int oa = scr_aa[x];
                int oc = scr_cc[x];

                /* Hack -- Ignore "non-changes" */
                if ((oa == na) && (oc == nc)) continue;

#ifdef JP
                /*
                 * Á´³Ñʸ»ú¤Îº¸È¾Ê¬¤Çɽ¼¨¤ò½ªÎ»¤¹¤ë¾ì¹ç¡¢
                 * ½Å¤Ê¤Ã¤¿Ê¸»ú¤Î±¦Éôʬ¤ò¾Ãµî¡£
                 *
                 * 2001/04/29 -- Habu
                 * ¹Ô¤Î±¦Ã¼¤Î¾ì¹ç¤Ï¤³¤Î½èÍý¤ò¤·¤Ê¤¤¤è¤¦¤Ë½¤Àµ¡£
                 */
                if ((oa & KANJI1) && (i + 1) == n && x != w - 1)
                        n++;
#endif
                /* Save the "literal" information */
                scr_aa[x] = na;
                scr_cc[x] = nc;

#ifdef USE_TRANSPARENCY
                scr_taa[x] = 0;
                scr_tcc[x] = 0;
#endif /* USE_TRANSPARENCY */

                /* Track minimum changed column */
                if (x1 < 0) x1 = x;

                /* Track maximum changed column */
                x2 = x;
        }

        /* Expand the "change area" as needed */
        if (x1 >= 0)
        {
                /* Check for new min/max row info */
                if (y < Term->y1) Term->y1 = y;
                if (y > Term->y2) Term->y2 = y;

                /* Check for new min/max col info in this row */
                if (x1 < Term->x1[y]) Term->x1[y] = x1;
                if (x2 > Term->x2[y]) Term->x2[y] = x2;
        }

        /* Success */
        return (0);
}


/*
 * Clear the entire window, and move to the top left corner
 *
 * Note the use of the special "total_erase" code
 */
errr Term_clear(void)
{
        int x, y;

        int w = Term->wid;
        int h = Term->hgt;

        byte na = Term->attr_blank;
        char nc = Term->char_blank;

        /* Cursor usable */
        Term->scr->cu = 0;

        /* Cursor to the top left */
        Term->scr->cx = Term->scr->cy = 0;

        /* Wipe each row */
        for (y = 0; y < h; y++)
        {
                byte *scr_aa = Term->scr->a[y];
                char *scr_cc = Term->scr->c[y];

#ifdef USE_TRANSPARENCY
                byte *scr_taa = Term->scr->ta[y];
                char *scr_tcc = Term->scr->tc[y];
#endif /* USE_TRANSPARENCY */

                /* Wipe each column */
                for (x = 0; x < w; x++)
                {
                        scr_aa[x] = na;
                        scr_cc[x] = nc;

#ifdef USE_TRANSPARENCY
                        scr_taa[x] = 0;
                        scr_tcc[x] = 0;
#endif /* USE_TRANSPARENCY */

                }

                /* This row has changed */
                Term->x1[y] = 0;
                Term->x2[y] = w - 1;
        }

        /* Every row has changed */
        Term->y1 = 0;
        Term->y2 = h - 1;

        /* Force "total erase" */
        Term->total_erase = TRUE;

        /* Success */
        return (0);
}





/*
 * Redraw (and refresh) the whole window.
 */
errr Term_redraw(void)
{
        /* Force "total erase" */
        Term->total_erase = TRUE;

        /* Hack -- Refresh */
        Term_fresh();

        /* Success */
        return (0);
}


/*
 * Redraw part of a widow.
 */
errr Term_redraw_section(int x1, int y1, int x2, int y2)
{
        int i, j;

        char *c_ptr;

        /* Bounds checking */
        if (y2 >= Term->hgt) y2 = Term->hgt - 1;
        if (x2 >= Term->wid) x2 = Term->wid - 1;
        if (y1 < 0) y1 = 0;
        if (x1 < 0) x1 = 0;

        /* Set y limits */
        Term->y1 = y1;
        Term->y2 = y2;

        /* Set the x limits */
        for (i = Term->y1; i <= Term->y2; i++)
        {
#ifdef JP
                int x1j = x1;
                int x2j = x2;
   
                if (x1j > 0)
                {
                        if (Term->scr->a[i][x1j] & KANJI2) x1j--;
                }
   
                if (x2j < Term->wid - 1)
                {
                        if (Term->scr->a[i][x2j] & KANJI1) x2j++;
                }
   
                Term->x1[i] = x1j;
                Term->x2[i] = x2j;
   
                c_ptr = Term->old->c[i];
   
                /* Clear the section so it is redrawn */
                for (j = x1j; j <= x2j; j++)
                {
                        /* Hack - set the old character to "none" */
                        c_ptr[j] = 0;
                }
#else
                Term->x1[i] = x1;
                Term->x2[i] = x2;

                c_ptr = Term->old->c[i];

                /* Clear the section so it is redrawn */
                for (j = x1; j <= x2; j++)
                {
                        /* Hack - set the old character to "none" */
                        c_ptr[j] = 0;
                }
#endif
        }

        /* Hack -- Refresh */
        Term_fresh();

        /* Success */
        return (0);
}



/*** Access routines ***/


/*
 * Extract the cursor visibility
 */
errr Term_get_cursor(int *v)
{
        /* Extract visibility */
        (*v) = Term->scr->cv;

        /* Success */
        return (0);
}


/*
 * Extract the current window size
 */
errr Term_get_size(int *w, int *h)
{
        /* Access the cursor */
        (*w) = Term->wid;
        (*h) = Term->hgt;

        /* Success */
        return (0);
}


/*
 * Extract the current cursor location
 */
errr Term_locate(int *x, int *y)
{
        /* Access the cursor */
        (*x) = Term->scr->cx;
        (*y) = Term->scr->cy;

        /* Warn about "useless" cursor */
        if (Term->scr->cu) return (1);

        /* Success */
        return (0);
}


/*
 * At a given location, determine the "current" attr and char
 * Note that this refers to what will be on the window after the
 * next call to "Term_fresh()".  It may or may not already be there.
 */
errr Term_what(int x, int y, byte *a, char *c)
{
        int w = Term->wid;
        int h = Term->hgt;

        /* Verify location */
        if ((x < 0) || (x >= w)) return (-1);
        if ((y < 0) || (y >= h)) return (-1);

        /* Direct access */
        (*a) = Term->scr->a[y][x];
        (*c) = Term->scr->c[y][x];

        /* Success */
        return (0);
}



/*** Input routines ***/


/*
 * Flush and forget the input
 */
errr Term_flush(void)
{
        /* Hack -- Flush all events */
        Term_xtra(TERM_XTRA_FLUSH, 0);

        /* Forget all keypresses */
        Term->key_head = Term->key_tail = 0;

        /* Success */
        return (0);
}



/*
 * Add a keypress to the "queue"
 */
errr Term_keypress(int k)
{
        /* Hack -- Refuse to enqueue non-keys */
        if (!k) return (-1);

        /* Store the char, advance the queue */
        Term->key_queue[Term->key_head++] = k;

        /* Circular queue, handle wrap */
        if (Term->key_head == Term->key_size) Term->key_head = 0;

        /* Success (unless overflow) */
        if (Term->key_head != Term->key_tail) return (0);

#if 0
        /* Hack -- Forget the oldest key */
        if (++Term->key_tail == Term->key_size) Term->key_tail = 0;
#endif

        /* Problem */
        return (1);
}


/*
 * Add a keypress to the FRONT of the "queue"
 */
errr Term_key_push(int k)
{
        /* Hack -- Refuse to enqueue non-keys */
        if (!k) return (-1);

        /* Hack -- Overflow may induce circular queue */
        if (Term->key_tail == 0) Term->key_tail = Term->key_size;

        /* Back up, Store the char */
        Term->key_queue[--Term->key_tail] = k;

        /* Success (unless overflow) */
        if (Term->key_head != Term->key_tail) return (0);

#if 0
        /* Hack -- Forget the oldest key */
        if (++Term->key_tail == Term->key_size) Term->key_tail = 0;
#endif

        /* Problem */
        return (1);
}





/*
 * Check for a pending keypress on the key queue.
 *
 * Store the keypress, if any, in "ch", and return "0".
 * Otherwise store "zero" in "ch", and return "1".
 *
 * Wait for a keypress if "wait" is true.
 *
 * Remove the keypress if "take" is true.
 */
errr Term_inkey(char *ch, bool wait, bool take)
{
        /* Assume no key */
        (*ch) = '\0';

#ifdef CHUUKEI
        flush_ringbuf();
#endif

        /* Hack -- get bored */
        if (!Term->never_bored)
        {
                /* Process random events */
                Term_xtra(TERM_XTRA_BORED, 0);
        }

        /* Wait */
        if (wait)
        {
                /* Process pending events while necessary */
                while (Term->key_head == Term->key_tail)
                {
                        /* Process events (wait for one) */
                        Term_xtra(TERM_XTRA_EVENT, TRUE);
                }
        }

        /* Do not Wait */
        else
        {
                /* Process pending events if necessary */
                if (Term->key_head == Term->key_tail)
                {
                        /* Process events (do not wait) */
                        Term_xtra(TERM_XTRA_EVENT, FALSE);
                }
        }

        /* No keys are ready */
        if (Term->key_head == Term->key_tail) return (1);

        /* Extract the next keypress */
        (*ch) = Term->key_queue[Term->key_tail];

        /* If requested, advance the queue, wrap around if necessary */
        if (take && (++Term->key_tail == Term->key_size)) Term->key_tail = 0;

        /* Success */
        return (0);
}



/*** Extra routines ***/


/*
 * Save the "requested" screen into the "memorized" screen
 *
 * Every "Term_save()" should match exactly one "Term_load()"
 */
errr Term_save(void)
{
        int w = Term->wid;
        int h = Term->hgt;

        /* Create */
        if (!Term->mem)
        {
                /* Allocate window */
                MAKE(Term->mem, term_win);

                /* Initialize window */
                term_win_init(Term->mem, w, h);
        }

        /* Grab */
        term_win_copy(Term->mem, Term->scr, w, h);

        /* Success */
        return (0);
}


/*
 * Restore the "requested" contents (see above).
 *
 * Every "Term_save()" should match exactly one "Term_load()"
 */
errr Term_load(void)
{
        int y;

        int w = Term->wid;
        int h = Term->hgt;

        /* Create */
        if (!Term->mem)
        {
                /* Allocate window */
                MAKE(Term->mem, term_win);

                /* Initialize window */
                term_win_init(Term->mem, w, h);
        }

        /* Load */
        term_win_copy(Term->scr, Term->mem, w, h);

        /* Assume change */
        for (y = 0; y < h; y++)
        {
                /* Assume change */
                Term->x1[y] = 0;
                Term->x2[y] = w - 1;
        }

        /* Assume change */
        Term->y1 = 0;
        Term->y2 = h - 1;

        /* Success */
        return (0);
}


/*
 * Exchange the "requested" screen with the "tmp" screen
 */
errr Term_exchange(void)
{
        int y;

        int w = Term->wid;
        int h = Term->hgt;

        term_win *exchanger;


        /* Create */
        if (!Term->tmp)
        {
                /* Allocate window */
                MAKE(Term->tmp, term_win);

                /* Initialize window */
                term_win_init(Term->tmp, w, h);
        }

        /* Swap */
        exchanger = Term->scr;
        Term->scr = Term->tmp;
        Term->tmp = exchanger;

        /* Assume change */
        for (y = 0; y < h; y++)
        {
                /* Assume change */
                Term->x1[y] = 0;
                Term->x2[y] = w - 1;
        }

        /* Assume change */
        Term->y1 = 0;
        Term->y2 = h - 1;

        /* Success */
        return (0);
}



/*
 * React to a new physical window size.
 */
errr Term_resize(int w, int h)
{
        int i;

        int wid, hgt;

        byte *hold_x1;
        byte *hold_x2;

        term_win *hold_old;
        term_win *hold_scr;
        term_win *hold_mem;
        term_win *hold_tmp;

        /* Resizing is forbidden */
        if (Term->fixed_shape) return (-1);

        /* Ignore illegal changes */
        if ((w < 1) || (h < 1)) return (-1);


        /* Ignore non-changes */
        if ((Term->wid == w) && (Term->hgt == h) && (arg_bigtile == use_bigtile))
                return (1);

        use_bigtile = arg_bigtile;

        /* Minimum dimensions */
        wid = MIN(Term->wid, w);
        hgt = MIN(Term->hgt, h);

        /* Save scanners */
        hold_x1 = Term->x1;
        hold_x2 = Term->x2;

        /* Save old window */
        hold_old = Term->old;

        /* Save old window */
        hold_scr = Term->scr;

        /* Save old window */
        hold_mem = Term->mem;

        /* Save old window */
        hold_tmp = Term->tmp;

        /* Create new scanners */
        C_MAKE(Term->x1, h, byte);
        C_MAKE(Term->x2, h, byte);

        /* Create new window */
        MAKE(Term->old, term_win);

        /* Initialize new window */
        term_win_init(Term->old, w, h);

        /* Save the contents */
        term_win_copy(Term->old, hold_old, wid, hgt);

        /* Create new window */
        MAKE(Term->scr, term_win);

        /* Initialize new window */
        term_win_init(Term->scr, w, h);

        /* Save the contents */
        term_win_copy(Term->scr, hold_scr, wid, hgt);

        /* If needed */
        if (hold_mem)
        {
                /* Create new window */
                MAKE(Term->mem, term_win);

                /* Initialize new window */
                term_win_init(Term->mem, w, h);

                /* Save the contents */
                term_win_copy(Term->mem, hold_mem, wid, hgt);
        }

        /* If needed */
        if (hold_tmp)
        {
                /* Create new window */
                MAKE(Term->tmp, term_win);

                /* Initialize new window */
                term_win_init(Term->tmp, w, h);

                /* Save the contents */
                term_win_copy(Term->tmp, hold_tmp, wid, hgt);
        }

        /* Free some arrays */
        C_KILL(hold_x1, Term->hgt, byte);
        C_KILL(hold_x2, Term->hgt, byte);

        /* Nuke */
        term_win_nuke(hold_old, Term->wid, Term->hgt);

        /* Kill */
        KILL(hold_old, term_win);

        /* Illegal cursor */
        if (Term->old->cx >= w) Term->old->cu = 1;
        if (Term->old->cy >= h) Term->old->cu = 1;

        /* Nuke */
        term_win_nuke(hold_scr, Term->wid, Term->hgt);

        /* Kill */
        KILL(hold_scr, term_win);

        /* Illegal cursor */
        if (Term->scr->cx >= w) Term->scr->cu = 1;
        if (Term->scr->cy >= h) Term->scr->cu = 1;

        /* If needed */
        if (hold_mem)
        {
                /* Nuke */
                term_win_nuke(hold_mem, Term->wid, Term->hgt);

                /* Kill */
                KILL(hold_mem, term_win);

                /* Illegal cursor */
                if (Term->mem->cx >= w) Term->mem->cu = 1;
                if (Term->mem->cy >= h) Term->mem->cu = 1;
        }

        /* If needed */
        if (hold_tmp)
        {
                /* Nuke */
                term_win_nuke(hold_tmp, Term->wid, Term->hgt);

                /* Kill */
                KILL(hold_tmp, term_win);

                /* Illegal cursor */
                if (Term->tmp->cx >= w) Term->tmp->cu = 1;
                if (Term->tmp->cy >= h) Term->tmp->cu = 1;
        }

        /* Save new size */
        Term->wid = w;
        Term->hgt = h;

        /* Force "total erase" */
        Term->total_erase = TRUE;

        /* Assume change */
        for (i = 0; i < h; i++)
        {
                /* Assume change */
                Term->x1[i] = 0;
                Term->x2[i] = w - 1;
        }

        /* Assume change */
        Term->y1 = 0;
        Term->y2 = h - 1;

        /* Execute the "resize_hook" hook, if available */
        if (Term->resize_hook)
        {
                Term->resize_hook();
        }

        /* Success */
        return (0);
}



/*
 * Activate a new Term (and deactivate the current Term)
 *
 * This function is extremely important, and also somewhat bizarre.
 * It is the only function that should "modify" the value of "Term".
 *
 * To "create" a valid "term", one should do "term_init(t)", then
 * set the various flags and hooks, and then do "Term_activate(t)".
 */
errr Term_activate(term *t)
{
        /* Hack -- already done */
        if (Term == t) return (1);

        /* Deactivate the old Term */
        if (Term) Term_xtra(TERM_XTRA_LEVEL, 0);

        /* Hack -- Call the special "init" hook */
        if (t && !t->active_flag)
        {
                /* Call the "init" hook */
                if (t->init_hook) (*t->init_hook)(t);

                /* Remember */
                t->active_flag = TRUE;

                /* Assume mapped */
                t->mapped_flag = TRUE;
        }

        /* Remember the Term */
        Term = t;

        /* Activate the new Term */
        if (Term) Term_xtra(TERM_XTRA_LEVEL, 1);

        /* Success */
        return (0);
}



/*
 * Nuke a term
 */
errr term_nuke(term *t)
{
        int w = t->wid;
        int h = t->hgt;


        /* Hack -- Call the special "nuke" hook */
        if (t->active_flag)
        {
                /* Call the "nuke" hook */
                if (t->nuke_hook) (*t->nuke_hook)(t);

                /* Remember */
                t->active_flag = FALSE;

                /* Assume not mapped */
                t->mapped_flag = FALSE;
        }


        /* Nuke "displayed" */
        term_win_nuke(t->old, w, h);

        /* Kill "displayed" */
        KILL(t->old, term_win);

        /* Nuke "requested" */
        term_win_nuke(t->scr, w, h);

        /* Kill "requested" */
        KILL(t->scr, term_win);

        /* If needed */
        if (t->mem)
        {
                /* Nuke "memorized" */
                term_win_nuke(t->mem, w, h);

                /* Kill "memorized" */
                KILL(t->mem, term_win);
        }

        /* If needed */
        if (t->tmp)
        {
                /* Nuke "temporary" */
                term_win_nuke(t->tmp, w, h);

                /* Kill "temporary" */
                KILL(t->tmp, term_win);
        }

        /* Free some arrays */
        C_KILL(t->x1, h, byte);
        C_KILL(t->x2, h, byte);

        /* Free the input queue */
        C_KILL(t->key_queue, t->key_size, char);

        /* Success */
        return (0);
}


/*
 * Initialize a term, using a window of the given size.
 * Also prepare the "input queue" for "k" keypresses
 * By default, the cursor starts out "invisible"
 * By default, we "erase" using "black spaces"
 */
errr term_init(term *t, int w, int h, int k)
{
        int y;


        /* Wipe it */
        (void)WIPE(t, term);


        /* Prepare the input queue */
        t->key_head = t->key_tail = 0;

        /* Determine the input queue size */
        t->key_size = k;

        /* Allocate the input queue */
        C_MAKE(t->key_queue, t->key_size, char);


        /* Save the size */
        t->wid = w;
        t->hgt = h;

        /* Allocate change arrays */
        C_MAKE(t->x1, h, byte);
        C_MAKE(t->x2, h, byte);


        /* Allocate "displayed" */
        MAKE(t->old, term_win);

        /* Initialize "displayed" */
        term_win_init(t->old, w, h);


        /* Allocate "requested" */
        MAKE(t->scr, term_win);

        /* Initialize "requested" */
        term_win_init(t->scr, w, h);


        /* Assume change */
        for (y = 0; y < h; y++)
        {
                /* Assume change */
                t->x1[y] = 0;
                t->x2[y] = w - 1;
        }

        /* Assume change */
        t->y1 = 0;
        t->y2 = h - 1;

        /* Force "total erase" */
        t->total_erase = TRUE;


        /* Default "blank" */
        t->attr_blank = 0;
        t->char_blank = ' ';


        /* Success */
        return (0);
}