/**
* Started up for scene script and entrance script.
*/
static void SceneTinselProcess(CORO_PARAM, const void *param) {
// COROUTINE
CORO_BEGIN_CONTEXT;
INT_CONTEXT *pic;
const TP_INIT *pInit;
int myEscape;
CORO_END_CONTEXT(_ctx);
CORO_BEGIN_CODE(_ctx);
// The following myEscape value setting is used for enabling title screen skipping in DW1
if (TinselV1 && (sceneCtr == 1)) initialMyEscape = GetEscEvents();
_ctx->myEscape = (TinselV1 && (sceneCtr < 4)) ? initialMyEscape : 0;
// get the stuff copied to process when it was created
_ctx->pInit = (const TP_INIT *)param;
assert(_ctx->pInit);
assert(_ctx->pInit->hTinselCode); // Must have some code to run
_ctx->pic = InitInterpretContext(GS_SCENE,
READ_LE_UINT32(&_ctx->pInit->hTinselCode),
TinselV2 ? _ctx->pInit->event : NOEVENT,
NOPOLY, // No polygon
0, // No actor
NULL, // No object
_ctx->myEscape);
CORO_INVOKE_1(Interpret, _ctx->pic);
if (_ctx->pInit->event == CLOSEDOWN || _ctx->pInit->event == LEAVE_T2)
bWatchingOut = false;
CORO_END_CODE;
}
void UpdateActorEsc(int ano, int escEvent) {
RANGE_CHECK(ano);
if (escEvent) {
actorInfo[ano - 1].bEscOn = true;
actorInfo[ano - 1].escEvent = escEvent;
} else {
actorInfo[ano - 1].bEscOn = false;
actorInfo[ano - 1].escEvent = GetEscEvents();
}
}
/**
* Interprets the PCODE instructions in the code array.
*/
void Interpret(CORO_PARAM, INT_CONTEXT *ic) {
do {
int tmp, tmp2;
int ip = ic->ip;
const WorkaroundEntry *wkEntry = ic->fragmentPtr;
if (wkEntry == NULL) {
// Check to see if a workaround fragment needs to be executed
for (wkEntry = workaroundList; wkEntry->script != NULL; ++wkEntry) {
if ((wkEntry->version == TinselVersion) &&
(wkEntry->hCode == ic->hCode) &&
(wkEntry->ip == ip) &&
(!TinselV1 || (wkEntry->scnFlag == ((_vm->getFeatures() & GF_SCNFILES) != 0)))) {
// Point to start of workaround fragment
ip = 0;
break;
}
}
if (wkEntry->script == NULL)
wkEntry = NULL;
}
byte opcode = (byte)GetBytes(ic->code, wkEntry, ip, 0);
if (TinselV0 && ((opcode & OPMASK) > OP_IMM))
opcode += 3;
debug(7, "ip=%d Opcode %d (-> %d)", ic->ip, opcode, opcode & OPMASK);
switch (opcode & OPMASK) {
case OP_HALT: // end of program
ic->bHalt = true;
break;
case OP_IMM: // loads immediate data onto stack
case OP_STR: // loads string handle onto stack
case OP_FILM: // loads film handle onto stack
case OP_CDFILM: // loads film handle onto stack
case OP_FONT: // loads font handle onto stack
case OP_PAL: // loads palette handle onto stack
ic->stack[++ic->sp] = Fetch(opcode, ic->code, wkEntry, ip);
break;
case OP_ZERO: // loads zero onto stack
ic->stack[++ic->sp] = 0;
break;
case OP_ONE: // loads one onto stack
ic->stack[++ic->sp] = 1;
break;
case OP_MINUSONE: // loads minus one onto stack
ic->stack[++ic->sp] = -1;
break;
case OP_LOAD: // loads local variable onto stack
ic->stack[++ic->sp] = ic->stack[ic->bp + Fetch(opcode, ic->code, wkEntry, ip)];
break;
case OP_GLOAD: // loads global variable onto stack
tmp = Fetch(opcode, ic->code, wkEntry, ip);
assert(0 <= tmp && tmp < numGlobals);
ic->stack[++ic->sp] = pGlobals[tmp];
break;
case OP_STORE: // pops stack and stores in local variable
ic->stack[ic->bp + Fetch(opcode, ic->code, wkEntry, ip)] = ic->stack[ic->sp--];
break;
case OP_GSTORE: // pops stack and stores in global variable
tmp = Fetch(opcode, ic->code, wkEntry, ip);
assert(0 <= tmp && tmp < numGlobals);
pGlobals[tmp] = ic->stack[ic->sp--];
break;
case OP_CALL: // procedure call
tmp = Fetch(opcode, ic->code, wkEntry, ip);
//assert(0 <= tmp && tmp < codeSize); // TODO: Verify jumps are not out of bounds
ic->stack[ic->sp + 1] = 0; // static link
ic->stack[ic->sp + 2] = ic->bp; // dynamic link
ic->stack[ic->sp + 3] = ip; // return address
ic->bp = ic->sp + 1; // set new base pointer
ip = tmp; // set ip to procedure address
break;
case OP_LIBCALL: // library procedure or function call
tmp = Fetch(opcode, ic->code, wkEntry, ip);
// NOTE: Interpret() itself is not using the coroutine facilities,
// but still accepts a CORO_PARAM, so from the outside it looks
// like a coroutine. In fact it may still acts as a kind of "proxy"
// for some underlying coroutine. To enable this, we just pass on
// 'coroParam' to CallLibraryRoutine(). If we then detect that
// coroParam was set to a non-zero value, this means that some
// coroutine code did run at some point, and we are now supposed
// to sleep or die -- hence, we 'return' if coroParam != 0.
//
// This works because Interpret() is fully re-entrant: If we return
// now and are later called again, then we will end up in the very
// same spot (i.e. here).
//
// The reasons we do it this way, instead of turning Interpret into
// a 'proper' coroutine are (1) we avoid implementation problems
// (CORO_INVOKE involves adding 'case' statements, but Interpret
// already has a huge switch/case, so that would not work out of the
// box), (2) we incurr less overhead, (3) it's easier to debug,
// (4) it's simply cool ;).
tmp2 = CallLibraryRoutine(coroParam, tmp, &ic->stack[ic->sp], ic, &ic->resumeState);
if (coroParam)
return;
if (!TinselV0)
ic->sp += tmp2;
LockCode(ic);
if (TinselV2 && (ic->resumeState == RES_1))
ic->resumeState = RES_NOT;
break;
case OP_RET: // procedure return
ic->sp = ic->bp - 1; // restore stack
ip = ic->stack[ic->sp + 3]; // return address
ic->bp = ic->stack[ic->sp + 2]; // restore previous base pointer
break;
case OP_ALLOC: // allocate storage on stack
ic->sp += (int32)Fetch(opcode, ic->code, wkEntry, ip);
break;
case OP_JUMP: // unconditional jump
ip = Fetch(opcode, ic->code, wkEntry, ip);
wkEntry = NULL; // In case a jump occurs from a workaround
break;
case OP_JMPFALSE: // conditional jump
tmp = Fetch(opcode, ic->code, wkEntry, ip);
if (ic->stack[ic->sp--] == 0) {
// condition satisfied - do the jump
ip = tmp;
wkEntry = NULL; // In case a jump occurs from a workaround
}
break;
case OP_JMPTRUE: // conditional jump
tmp = Fetch(opcode, ic->code, wkEntry, ip);
if (ic->stack[ic->sp--] != 0) {
// condition satisfied - do the jump
ip = tmp;
wkEntry = NULL; // In case a jump occurs from a workaround
}
break;
case OP_EQUAL: // tests top two items on stack for equality
case OP_LESS: // tests top two items on stack
case OP_LEQUAL: // tests top two items on stack
case OP_NEQUAL: // tests top two items on stack
case OP_GEQUAL: // tests top two items on stack
case OP_GREAT: // tests top two items on stack
case OP_LOR: // logical or of top two items on stack and replaces with result
case OP_LAND: // logical ands top two items on stack and replaces with result
// pop one operand
ic->sp--;
assert(ic->sp >= 0);
tmp = ic->stack[ic->sp];
tmp2 = ic->stack[ic->sp + 1];
// replace other operand with result of operation
switch (opcode) {
case OP_EQUAL: tmp = (tmp == tmp2); break;
case OP_LESS: tmp = (tmp < tmp2); break;
case OP_LEQUAL: tmp = (tmp <= tmp2); break;
case OP_NEQUAL: tmp = (tmp != tmp2); break;
case OP_GEQUAL: tmp = (tmp >= tmp2); break;
case OP_GREAT: tmp = (tmp > tmp2); break;
case OP_LOR: tmp = (tmp || tmp2); break;
case OP_LAND: tmp = (tmp && tmp2); break;
}
ic->stack[ic->sp] = tmp;
break;
case OP_PLUS: // adds top two items on stack and replaces with result
case OP_MINUS: // subs top two items on stack and replaces with result
case OP_MULT: // multiplies top two items on stack and replaces with result
case OP_DIV: // divides top two items on stack and replaces with result
case OP_MOD: // divides top two items on stack and replaces with modulus
case OP_AND: // bitwise ands top two items on stack and replaces with result
case OP_OR: // bitwise ors top two items on stack and replaces with result
case OP_EOR: // bitwise exclusive ors top two items on stack and replaces with result
// pop one operand
ic->sp--;
assert(ic->sp >= 0);
tmp = ic->stack[ic->sp];
tmp2 = ic->stack[ic->sp + 1];
// replace other operand with result of operation
switch (opcode) {
case OP_PLUS: tmp += tmp2; break;
case OP_MINUS: tmp -= tmp2; break;
case OP_MULT: tmp *= tmp2; break;
case OP_DIV: tmp /= tmp2; break;
case OP_MOD: tmp %= tmp2; break;
case OP_AND: tmp &= tmp2; break;
case OP_OR: tmp |= tmp2; break;
case OP_EOR: tmp ^= tmp2; break;
}
ic->stack[ic->sp] = tmp;
break;
case OP_NOT: // logical nots top item on stack
ic->stack[ic->sp] = !ic->stack[ic->sp];
break;
case OP_COMP: // complements top item on stack
ic->stack[ic->sp] = ~ic->stack[ic->sp];
break;
case OP_NEG: // negates top item on stack
ic->stack[ic->sp] = -ic->stack[ic->sp];
break;
case OP_DUP: // duplicates top item on stack
ic->stack[ic->sp + 1] = ic->stack[ic->sp];
ic->sp++;
break;
case OP_ESCON:
bNoPause = true;
ic->escOn = true;
ic->myEscape = GetEscEvents();
break;
case OP_ESCOFF:
ic->escOn = false;
ic->myEscape = 0;
break;
default:
error("Interpret() - Unknown opcode");
}
// check for stack under-overflow
assert(ic->sp >= 0 && ic->sp < PCODE_STACK_SIZE);
ic->ip = ip;
ic->fragmentPtr = wkEntry;
} while (!ic->bHalt);
// make sure stack is unwound
assert(ic->sp == 0);
FreeInterpretContextPi(ic);
}
