nethack-gwaa-kiwi/nethack
1
0
Fork 0
Code Pull Requests Activity

split g into multiple structures

Browse Source 
The consolidation of global variables from scattered source
files into decl.c and declared in decl.h was begun in 3.7.0.
Their placement in common files was done for centralized
initialization and potential re-initialization during a
"play again" scenario.

It wasn't really necessary for all of them to be housed in a
single huge structure to meet the "play again" requirement,
and the single huge structure has been a little unwieldy when
it comes to maintenance.

Following this commit, instead of one single extremely large structure
named 'g' to house all of the relocated global variables, they
are distributed into several ga through gz.

To make things easy for the developer, each variable is placed
into the struct corresponding to the starting letter of the variable.
That way, no lookup is required in order to know which struct houses
a particular variable, it is a simple match to the starting letter
for all the centralized global variables.

A global variable named 'amulets', would be found in ga.
    ga.amulets
     ^ ^
A global varable named 'move', would be found in gm.
    gm.moves
     ^ ^
A global variable named 'val_for_n_or_more' would be found in gv.
    gv.val_for_n_or_more
     ^ ^
A global variable named 'youmonst' would be found in gy.
    gy.youmonst
     ^ ^
This commit is contained in:
nhmall
2022-11-29 21:53:21 -05:00
parent e64ed2859d
commit 02a48aa8cf
193 changed files with 10764 additions and 10148 deletions
Download Patch File Download Diff File Expand all files Collapse all files

224
src/spell.c
View File

@@ -4,7 +4,7 @@
#include "hack.h"
/* spellmenu arguments; 0 thru n-1 used as g.spl_book[] index when swapping */
/* spellmenu arguments; 0 thru n-1 used as gs.spl_book[] index when swapping */
#define SPELLMENU_CAST (-2)
#define SPELLMENU_VIEW (-1)
#define SPELLMENU_SORT (MAXSPELL) /* special menu entry */
@@ -18,9 +18,9 @@
initialization; spell memory is decremented at the end of each turn,
including the turn on which the spellbook is read; without the extra
increment, the hero used to get cheated out of 1 turn of retention */
#define incrnknow(spell, x) (g.spl_book[spell].sp_know = KEEN + (x))
#define incrnknow(spell, x) (gs.spl_book[spell].sp_know = KEEN + (x))
#define spellev(spell) g.spl_book[spell].sp_lev
#define spellev(spell) gs.spl_book[spell].sp_lev
#define spellname(spell) OBJ_NAME(objects[spellid(spell)])
#define spellet(spell) \
((char) ((spell < 26) ? ('a' + spell) : ('A' + spell - 26)))
@@ -192,7 +192,7 @@ confused_book(struct obj* spellbook)
gone = TRUE;
} else {
You("find yourself reading the %s line over and over again.",
spellbook == g.context.spbook.book ? "next" : "first");
spellbook == gc.context.spbook.book ? "next" : "first");
}
return gone;
}
@@ -231,7 +231,7 @@ deadbook(struct obj* book2)
return;
}
for (otmp = g.invent; otmp; otmp = otmp->nobj) {
for (otmp = gi.invent; otmp; otmp = otmp->nobj) {
if (otmp->otyp == CANDELABRUM_OF_INVOCATION && otmp->spe == 7
&& otmp->lamplit) {
if (!otmp->cursed)
@@ -240,7 +240,7 @@ deadbook(struct obj* book2)
arti_cursed = TRUE;
}
if (otmp->otyp == BELL_OF_OPENING
&& (g.moves - otmp->age) < 5L) { /* you rang it recently */
&& (gm.moves - otmp->age) < 5L) { /* you rang it recently */
if (!otmp->cursed)
arti2_primed = TRUE;
else
@@ -287,7 +287,7 @@ deadbook(struct obj* book2)
set_malign(mtmp);
}
/* next handle the affect on things you're carrying */
(void) unturn_dead(&g.youmonst);
(void) unturn_dead(&gy.youmonst);
/* last place some monsters around you */
mm.x = u.ux;
mm.y = u.uy;
@@ -331,8 +331,8 @@ deadbook(struct obj* book2)
void
book_cursed(struct obj *book)
{
if (book->cursed && g.multi >= 0
&& g.occupation == learn && g.context.spbook.book == book) {
if (book->cursed && gm.multi >= 0
&& go.occupation == learn && gc.context.spbook.book == book) {
pline("%s shut!", Tobjnam(book, "slam"));
set_bknown(book, 1);
stop_occupation();
@@ -348,24 +348,24 @@ learn(void)
short booktype;
char splname[BUFSZ];
boolean costly = TRUE;
struct obj *book = g.context.spbook.book;
struct obj *book = gc.context.spbook.book;
/* JDS: lenses give 50% faster reading; 33% smaller read time */
if (g.context.spbook.delay && ublindf && ublindf->otyp == LENSES && rn2(2))
g.context.spbook.delay++;
if (gc.context.spbook.delay && ublindf && ublindf->otyp == LENSES && rn2(2))
gc.context.spbook.delay++;
if (Confusion) { /* became confused while learning */
(void) confused_book(book);
g.context.spbook.book = 0; /* no longer studying */
g.context.spbook.o_id = 0;
nomul(g.context.spbook.delay); /* remaining delay is uninterrupted */
g.multi_reason = "reading a book";
g.nomovemsg = 0;
g.context.spbook.delay = 0;
gc.context.spbook.book = 0; /* no longer studying */
gc.context.spbook.o_id = 0;
nomul(gc.context.spbook.delay); /* remaining delay is uninterrupted */
gm.multi_reason = "reading a book";
gn.nomovemsg = 0;
gc.context.spbook.delay = 0;
return 0;
}
if (g.context.spbook.delay) {
/* not if (g.context.spbook.delay++), so at end delay == 0 */
g.context.spbook.delay++;
if (gc.context.spbook.delay) {
/* not if (gc.context.spbook.delay++), so at end delay == 0 */
gc.context.spbook.delay++;
return 1; /* still busy */
}
exercise(A_WIS, TRUE); /* you're studying. */
@@ -410,8 +410,8 @@ learn(void)
/* reset spestudied as if polymorph had taken place */
book->spestudied = rn2(book->spestudied);
} else {
g.spl_book[i].sp_id = booktype;
g.spl_book[i].sp_lev = objects[booktype].oc_level;
gs.spl_book[i].sp_id = booktype;
gs.spl_book[i].sp_lev = objects[booktype].oc_level;
incrnknow(i, 1);
book->spestudied++;
if (!i)
@@ -427,15 +427,15 @@ learn(void)
if (book->cursed) { /* maybe a demon cursed it */
if (cursed_book(book)) {
useup(book);
g.context.spbook.book = 0;
g.context.spbook.o_id = 0;
gc.context.spbook.book = 0;
gc.context.spbook.o_id = 0;
return 0;
}
}
if (costly)
check_unpaid(book);
g.context.spbook.book = 0;
g.context.spbook.o_id = 0;
gc.context.spbook.book = 0;
gc.context.spbook.o_id = 0;
return 0;
}
@@ -455,12 +455,12 @@ study_book(register struct obj* spellbook)
int dullbook = rnd(25) - ACURR(A_WIS);
/* adjust chance if hero stayed awake, got interrupted, retries */
if (g.context.spbook.delay && spellbook == g.context.spbook.book)
if (gc.context.spbook.delay && spellbook == gc.context.spbook.book)
dullbook -= rnd(objects[booktype].oc_level);
if (dullbook > 0) {
eyes = body_part(EYE);
if (eyecount(g.youmonst.data) > 1)
if (eyecount(gy.youmonst.data) > 1)
eyes = makeplural(eyes);
pline("This book is so dull that you can't keep your %s open.",
eyes);
@@ -470,10 +470,10 @@ study_book(register struct obj* spellbook)
}
}
if (g.context.spbook.delay && !confused
&& spellbook == g.context.spbook.book
if (gc.context.spbook.delay && !confused
&& spellbook == gc.context.spbook.book
/* handle the sequence: start reading, get interrupted, have
g.context.spbook.book become erased somehow, resume reading it */
gc.context.spbook.book become erased somehow, resume reading it */
&& booktype != SPE_BLANK_PAPER) {
You("continue your efforts to %s.",
(booktype == SPE_NOVEL) ? "read the novel" : "memorize the spell");
@@ -512,20 +512,20 @@ study_book(register struct obj* spellbook)
switch (objects[booktype].oc_level) {
case 1:
case 2:
g.context.spbook.delay = -objects[booktype].oc_delay;
gc.context.spbook.delay = -objects[booktype].oc_delay;
break;
case 3:
case 4:
g.context.spbook.delay = -(objects[booktype].oc_level - 1)
gc.context.spbook.delay = -(objects[booktype].oc_level - 1)
* objects[booktype].oc_delay;
break;
case 5:
case 6:
g.context.spbook.delay =
gc.context.spbook.delay =
-objects[booktype].oc_level * objects[booktype].oc_delay;
break;
case 7:
g.context.spbook.delay = -8 * objects[booktype].oc_delay;
gc.context.spbook.delay = -8 * objects[booktype].oc_delay;
break;
default:
impossible("Unknown spellbook level %d, book %d;",
@@ -580,10 +580,10 @@ study_book(register struct obj* spellbook)
if (too_hard) {
boolean gone = cursed_book(spellbook);
nomul(g.context.spbook.delay); /* study time */
g.multi_reason = "reading a book";
g.nomovemsg = 0;
g.context.spbook.delay = 0;
nomul(gc.context.spbook.delay); /* study time */
gm.multi_reason = "reading a book";
gn.nomovemsg = 0;
gc.context.spbook.delay = 0;
if (gone || !rn2(3)) {
if (!gone)
pline_The("spellbook crumbles to dust!");
@@ -596,10 +596,10 @@ study_book(register struct obj* spellbook)
if (!confused_book(spellbook)) {
spellbook->in_use = FALSE;
}
nomul(g.context.spbook.delay);
g.multi_reason = "reading a book";
g.nomovemsg = 0;
g.context.spbook.delay = 0;
nomul(gc.context.spbook.delay);
gm.multi_reason = "reading a book";
gn.nomovemsg = 0;
gc.context.spbook.delay = 0;
return 1;
}
spellbook->in_use = FALSE;
@@ -608,9 +608,9 @@ study_book(register struct obj* spellbook)
spellbook->otyp == SPE_BOOK_OF_THE_DEAD ? "recite" : "memorize");
}
g.context.spbook.book = spellbook;
if (g.context.spbook.book)
g.context.spbook.o_id = g.context.spbook.book->o_id;
gc.context.spbook.book = spellbook;
if (gc.context.spbook.book)
gc.context.spbook.o_id = gc.context.spbook.book->o_id;
set_occupation(learn, "studying", 0);
return 1;
}
@@ -620,9 +620,9 @@ study_book(register struct obj* spellbook)
void
book_disappears(struct obj* obj)
{
if (obj == g.context.spbook.book) {
g.context.spbook.book = (struct obj *) 0;
g.context.spbook.o_id = 0;
if (obj == gc.context.spbook.book) {
gc.context.spbook.book = (struct obj *) 0;
gc.context.spbook.o_id = 0;
}
}
@@ -632,10 +632,10 @@ book_disappears(struct obj* obj)
void
book_substitution(struct obj* old_obj, struct obj* new_obj)
{
if (old_obj == g.context.spbook.book) {
g.context.spbook.book = new_obj;
if (g.context.spbook.book)
g.context.spbook.o_id = g.context.spbook.book->o_id;
if (old_obj == gc.context.spbook.book) {
gc.context.spbook.book = new_obj;
if (gc.context.spbook.book)
gc.context.spbook.o_id = gc.context.spbook.book->o_id;
}
}
@@ -665,7 +665,7 @@ rejectcasting(void)
if (Stunned) {
You("are too impaired to cast a spell.");
return TRUE;
} else if (!can_chant(&g.youmonst)) {
} else if (!can_chant(&gy.youmonst)) {
You("are unable to chant the incantation.");
return TRUE;
} else if (!freehand()) {
@@ -774,7 +774,7 @@ docast(void)
int spell_no;
if (getspell(&spell_no))
return spelleffects(g.spl_book[spell_no].sp_id, FALSE, FALSE);
return spelleffects(gs.spl_book[spell_no].sp_id, FALSE, FALSE);
return ECMD_OK;
}
@@ -963,7 +963,7 @@ spelleffects_check(int spell, int *res, int *energy)
u.uen -= rnd(*energy);
if (u.uen < 0)
u.uen = 0;
g.context.botl = 1;
gc.context.botl = 1;
*res = ECMD_TIME;
return TRUE;
} else if (spellknow(spell) <= KEEN / 200) { /* 100 turns left */
@@ -1006,7 +1006,7 @@ spelleffects_check(int spell, int *res, int *energy)
u.uen -= rnd(2 * *energy);
if (u.uen < 0)
u.uen = 0;
g.context.botl = 1;
gc.context.botl = 1;
*res = ECMD_TIME; /* time is used even if spell doesn't get cast */
}
@@ -1080,7 +1080,7 @@ spelleffects_check(int spell, int *res, int *energy)
if (confused || (rnd(100) > chance)) {
You("fail to cast the spell correctly.");
u.uen -= *energy / 2;
g.context.botl = 1;
gc.context.botl = 1;
*res = ECMD_TIME;
return TRUE;
}
@@ -1103,7 +1103,7 @@ spelleffects(int spell_otyp, boolean atme, boolean force)
return res;
u.uen -= energy;
g.context.botl = 1;
gc.context.botl = 1;
exercise(A_WIS, TRUE);
/* pseudo is a temporary "false" object containing the spell stats */
pseudo = mksobj(force ? spell : spellid(spell), FALSE, FALSE);
@@ -1391,14 +1391,14 @@ tport_spell(int what)
save_tport.tport_indx = MAXSPELL;
} else if (what == UNHIDESPELL) {
/*assert( save_tport.savespell.sp_id == SPE_TELEPORT_AWAY );*/
g.spl_book[save_tport.tport_indx] = save_tport.savespell;
gs.spl_book[save_tport.tport_indx] = save_tport.savespell;
save_tport.tport_indx = MAXSPELL; /* burn bridge... */
} else if (what == ADD_SPELL) {
save_tport.savespell = g.spl_book[i];
save_tport.savespell = gs.spl_book[i];
save_tport.tport_indx = i;
g.spl_book[i].sp_id = SPE_TELEPORT_AWAY;
g.spl_book[i].sp_lev = objects[SPE_TELEPORT_AWAY].oc_level;
g.spl_book[i].sp_know = KEEN;
gs.spl_book[i].sp_id = SPE_TELEPORT_AWAY;
gs.spl_book[i].sp_lev = objects[SPE_TELEPORT_AWAY].oc_level;
gs.spl_book[i].sp_know = KEEN;
return REMOVESPELL; /* operation needed to reverse */
}
} else { /* spellid(i) == SPE_TELEPORT_AWAY */
@@ -1406,12 +1406,12 @@ tport_spell(int what)
save_tport.tport_indx = MAXSPELL;
} else if (what == REMOVESPELL) {
/*assert( i == save_tport.tport_indx );*/
g.spl_book[i] = save_tport.savespell;
gs.spl_book[i] = save_tport.savespell;
save_tport.tport_indx = MAXSPELL;
} else if (what == HIDE_SPELL) {
save_tport.savespell = g.spl_book[i];
save_tport.savespell = gs.spl_book[i];
save_tport.tport_indx = i;
g.spl_book[i].sp_id = NO_SPELL;
gs.spl_book[i].sp_id = NO_SPELL;
return UNHIDESPELL; /* operation needed to reverse */
}
}
@@ -1427,8 +1427,8 @@ losespells(void)
int n, nzap, i;
/* in case reading has been interrupted earlier, discard context */
g.context.spbook.book = 0;
g.context.spbook.o_id = 0;
gc.context.spbook.book = 0;
gc.context.spbook.o_id = 0;
/* count the number of known spells */
for (n = 0; n < MAXSPELL; ++n)
if (spellid(n) == NO_SPELL)
@@ -1534,17 +1534,17 @@ spell_cmp(const genericptr vptr1, const genericptr vptr2)
/*
* gather up all of the possible parameters except spell name
* in advance, even though some might not be needed:
* indx. = spl_orderindx[] index into g.spl_book[];
* otyp. = g.spl_book[] index into objects[];
* indx. = spl_orderindx[] index into gs.spl_book[];
* otyp. = gs.spl_book[] index into objects[];
* levl. = spell level;
* skil. = skill group aka spell class.
*/
int indx1 = *(int *) vptr1, indx2 = *(int *) vptr2,
otyp1 = g.spl_book[indx1].sp_id, otyp2 = g.spl_book[indx2].sp_id,
otyp1 = gs.spl_book[indx1].sp_id, otyp2 = gs.spl_book[indx2].sp_id,
levl1 = objects[otyp1].oc_level, levl2 = objects[otyp2].oc_level,
skil1 = objects[otyp1].oc_skill, skil2 = objects[otyp2].oc_skill;
switch (g.spl_sortmode) {
switch (gs.spl_sortmode) {
case SORTBY_LETTER:
return indx1 - indx2;
case SORTBY_ALPHA:
@@ -1595,40 +1595,40 @@ sortspells(void)
int n;
#endif
if (g.spl_sortmode == SORTBY_CURRENT)
if (gs.spl_sortmode == SORTBY_CURRENT)
return;
for (n = 0; n < MAXSPELL && spellid(n) != NO_SPELL; ++n)
continue;
if (n < 2)
return; /* not enough entries to need sorting */
if (!g.spl_orderindx) {
if (!gs.spl_orderindx) {
/* we haven't done any sorting yet; list is in casting order */
if (g.spl_sortmode == SORTBY_LETTER /* default */
|| g.spl_sortmode == SORTRETAINORDER)
if (gs.spl_sortmode == SORTBY_LETTER /* default */
|| gs.spl_sortmode == SORTRETAINORDER)
return;
/* allocate enough for full spellbook rather than just N spells */
g.spl_orderindx = (int *) alloc(MAXSPELL * sizeof(int));
gs.spl_orderindx = (int *) alloc(MAXSPELL * sizeof(int));
for (i = 0; i < MAXSPELL; i++)
g.spl_orderindx[i] = i;
gs.spl_orderindx[i] = i;
}
if (g.spl_sortmode == SORTRETAINORDER) {
if (gs.spl_sortmode == SORTRETAINORDER) {
struct spell tmp_book[MAXSPELL];
/* sort g.spl_book[] rather than spl_orderindx[];
/* sort gs.spl_book[] rather than spl_orderindx[];
this also updates the index to reflect the new ordering (we
could just free it since that ordering becomes the default) */
for (i = 0; i < MAXSPELL; i++)
tmp_book[i] = g.spl_book[g.spl_orderindx[i]];
tmp_book[i] = gs.spl_book[gs.spl_orderindx[i]];
for (i = 0; i < MAXSPELL; i++)
g.spl_book[i] = tmp_book[i], g.spl_orderindx[i] = i;
g.spl_sortmode = SORTBY_LETTER; /* reset */
gs.spl_book[i] = tmp_book[i], gs.spl_orderindx[i] = i;
gs.spl_sortmode = SORTBY_LETTER; /* reset */
return;
}
/* usual case, sort the index rather than the spells themselves */
qsort((genericptr_t) g.spl_orderindx, n, sizeof *g.spl_orderindx, spell_cmp);
qsort((genericptr_t) gs.spl_orderindx, n, sizeof *gs.spl_orderindx, spell_cmp);
return;
}
@@ -1660,7 +1660,7 @@ spellsortmenu(void)
any.a_int = i + 1;
add_menu(tmpwin, &nul_glyphinfo, &any, let, 0,
ATR_NONE, clr, spl_sortchoices[i],
(i == g.spl_sortmode) ? MENU_ITEMFLAGS_SELECTED : MENU_ITEMFLAGS_NONE);
(i == gs.spl_sortmode) ? MENU_ITEMFLAGS_SELECTED : MENU_ITEMFLAGS_NONE);
}
end_menu(tmpwin, "View known spells list sorted");
@@ -1669,10 +1669,10 @@ spellsortmenu(void)
if (n > 0) {
choice = selected[0].item.a_int - 1;
/* skip preselected entry if we have more than one item chosen */
if (n > 1 && choice == g.spl_sortmode)
if (n > 1 && choice == gs.spl_sortmode)
choice = selected[1].item.a_int - 1;
free((genericptr_t) selected);
g.spl_sortmode = choice;
gs.spl_sortmode = choice;
return TRUE;
}
return FALSE;
@@ -1700,17 +1700,17 @@ dovspell(void)
if (!dospellmenu(qbuf, splnum, &othnum))
break;
spl_tmp = g.spl_book[splnum];
g.spl_book[splnum] = g.spl_book[othnum];
g.spl_book[othnum] = spl_tmp;
spl_tmp = gs.spl_book[splnum];
gs.spl_book[splnum] = gs.spl_book[othnum];
gs.spl_book[othnum] = spl_tmp;
}
}
}
if (g.spl_orderindx) {
free((genericptr_t) g.spl_orderindx);
g.spl_orderindx = 0;
if (gs.spl_orderindx) {
free((genericptr_t) gs.spl_orderindx);
gs.spl_orderindx = 0;
}
g.spl_sortmode = SORTBY_LETTER; /* 0 */
gs.spl_sortmode = SORTBY_LETTER; /* 0 */
return ECMD_OK;
}
@@ -1722,7 +1722,7 @@ DISABLE_WARNING_FORMAT_NONLITERAL
static boolean
dospellmenu(
const char *prompt,
int splaction, /* SPELLMENU_CAST, SPELLMENU_VIEW, or g.spl_book[] index */
int splaction, /* SPELLMENU_CAST, SPELLMENU_VIEW, or gs.spl_book[] index */
int *spell_no)
{
winid tmpwin;
@@ -1760,7 +1760,7 @@ dospellmenu(
add_menu(tmpwin, &nul_glyphinfo, &any, 0, 0,
iflags.menu_headings, clr, buf, MENU_ITEMFLAGS_NONE);
for (i = 0; i < MAXSPELL && spellid(i) != NO_SPELL; i++) {
splnum = !g.spl_orderindx ? i : g.spl_orderindx[i];
splnum = !gs.spl_orderindx ? i : gs.spl_orderindx[i];
Sprintf(buf, fmt, spellname(splnum), spellev(splnum),
spelltypemnemonic(spell_skilltype(spellid(splnum))),
100 - percent_success(splnum),
@@ -1828,17 +1828,17 @@ percent_success(int spell)
/* Calculate intrinsic ability (splcaster) */
splcaster = g.urole.spelbase;
special = g.urole.spelheal;
statused = ACURR(g.urole.spelstat);
splcaster = gu.urole.spelbase;
special = gu.urole.spelheal;
statused = ACURR(gu.urole.spelstat);
if (uarm && is_metallic(uarm) && !paladin_bonus)
splcaster += (uarmc && uarmc->otyp == ROBE) ? g.urole.spelarmr / 2
: g.urole.spelarmr;
splcaster += (uarmc && uarmc->otyp == ROBE) ? gu.urole.spelarmr / 2
: gu.urole.spelarmr;
else if (uarmc && uarmc->otyp == ROBE)
splcaster -= g.urole.spelarmr;
splcaster -= gu.urole.spelarmr;
if (uarms)
splcaster += g.urole.spelshld;
splcaster += gu.urole.spelshld;
if (!paladin_bonus) {
if (uarmh && is_metallic(uarmh) && uarmh->otyp != HELM_OF_BRILLIANCE)
@@ -1849,8 +1849,8 @@ percent_success(int spell)
splcaster += uarmfbon;
}
if (spellid(spell) == g.urole.spelspec)
splcaster += g.urole.spelsbon;
if (spellid(spell) == gu.urole.spelspec)
splcaster += gu.urole.spelsbon;
/* `healing spell' bonus */
if (spellid(spell) == SPE_HEALING || spellid(spell) == SPE_EXTRA_HEALING
@@ -1908,7 +1908,7 @@ percent_success(int spell)
* player's role-specific spell.
*/
if (uarms && weight(uarms) > (int) objects[SMALL_SHIELD].oc_weight) {
if (spellid(spell) == g.urole.spelspec) {
if (spellid(spell) == gu.urole.spelspec) {
chance /= 2;
} else {
chance /= 4;
@@ -1992,8 +1992,8 @@ initialspell(struct obj* obj)
/* initial inventory shouldn't contain duplicate spellbooks */
impossible("Spell %s already known.", OBJ_NAME(objects[otyp]));
} else {
g.spl_book[i].sp_id = otyp;
g.spl_book[i].sp_lev = objects[otyp].oc_level;
gs.spl_book[i].sp_id = otyp;
gs.spl_book[i].sp_lev = objects[otyp].oc_level;
incrnknow(i, 0);
}
return;
@@ -2046,8 +2046,8 @@ force_learn_spell(short otyp)
}
/* for a going-stale or forgotten spell the sp_id and sp_lev assignments
are redundant but harmless; for an unknown spell, they're essential */
g.spl_book[i].sp_id = otyp;
g.spl_book[i].sp_lev = objects[otyp].oc_level;
gs.spl_book[i].sp_id = otyp;
gs.spl_book[i].sp_lev = objects[otyp].oc_level;
incrnknow(i, 0); /* set spl_book[i].sp_know to KEEN; unlike when learning
* a spell by reading its book, we don't need to add 1 */
return spellet(i);