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SCI32: Fix QFG4 peering at absent bats
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Fixes castle doors when all bats have been killed, bug #10789
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@Vhati @bluegr
Vhati authored and bluegr committed Mar 2, 2019
1 parent e67b850 commit 0def174
Showing 1 changed file with 195 additions and 1 deletion.
196 changes: 195 additions & 1 deletion engines/sci/engine/script_patches.cpp
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Expand Up @@ -163,6 +163,7 @@ static const char *const selectorNameTable[] = {
"state", // RAMA
"getSubscriberObj", // RAMA
"approachVerbs", // QFG4
"changeState", // QFG4
"cue", // QFG4
"heading", // QFG4
"moveSpeed", // QFG4
Expand Down Expand Up @@ -257,6 +258,7 @@ enum ScriptPatcherSelectors {
SELECTOR_state,
SELECTOR_getSubscriberObj,
SELECTOR_approachVerbs,
SELECTOR_changeState,
SELECTOR_cue,
SELECTOR_heading,
SELECTOR_moveSpeed,
Expand Down Expand Up @@ -9106,6 +9108,192 @@ static const uint16 qfg4CrestBookshelfMotionPatch[] = {
PATCH_END
};

// In the crest bookshelf room (663) connected to the upper door of the
// bat-infested stairway, peering through the keyhole *always* reports bats.
//
// As you kill the bats, global plot flags are set. Normally flags 331-334
// would be checked via proc0_4(). They're in a bitmask, among other flags, so
// we can check all simultaneously (0000000000011110).
//
// global[520] & 30 == 30
//
// Patch 1: There was no space for this in the responsible method. Instead, we
// rewrite a different method that became obsolete after the crest bookshelf
// patch: sCloseSecretDoor::changeState().
//
// Patch 2: We modify sPeepingTom to call our rewritten sCloseSecretDoor. This
// has two variants, toggled to match the detected edition with enablePatch()
// below. Aside from the patched lofsa value, they are identical.
//
// Requires patch: qfg4CrestBookshelf (CD or Floppy)
// Applies to at least: English CD, English floppy, German floppy
// Responsible method: sPeepingTom::changeState(1) in script 663
// Fixes bug: #10789
static const uint16 qfg4UpperPeerBatsSignature1[] = {
0x87, 0x01, // lap param[1]
SIG_ADDTOOFFSET(+41), // ...
SIG_MAGICDWORD,
0x4a, SIG_UINT16(0x0006), // send 6d
0x35, 0x1e, // ldi 30d
0x65, SIG_ADDTOOFFSET(+1), // aTop ticks
SIG_ADDTOOFFSET(+9), // ...
0x38, SIG_SELECTOR16(setCycle), // pushi setCycle
SIG_END
};

static const uint16 qfg4UpperPeerBatsPatch1[] = {
0x38, PATCH_SELECTOR16(say), // pushi say (decide the message as args are stacked up)
0x39, 0x06, // pushi 6d
0x7a, // push2
0x38, PATCH_UINT16(0x009b), // pushi 155d

0x39, 0x1e, // pushi 30d (stack up for eq)
0x3c, // dup (stack up another for AND)
0x80, PATCH_UINT16(0x0208), // lag global[520] (plot flags bitmask)
0x12, // and
0x1a, // eq? (Were all dead bat flags set?)
0x2f, 0x04, // bt 4d [after this jmp]
0x39, 0x1d, // pushi 29d (bat message)
0x33, 0x02, // jmp 2d [after deciding message]

0x39, 0x1b, // pushi 27d (killed all bats, generic message)

0x78, // push1
0x76, // push0 (don't cue() afterward)
0x38, PATCH_UINT16(0x0280), // pushi 640d
0x81, 0x5b, // lag global[91] (gloryMessager)
0x4a, PATCH_UINT16(0x0010), // send 16d
0x48, // ret
0x34, PATCH_UINT16(0x0000), // ldi 0 (erase 3 bytes to keep disasm aligned)
PATCH_END
};

// Applies to at least: English CD
static const uint16 qfg4UpperPeerBatsCDSignature2[] = {
0x38, SIG_SELECTOR16(say), // pushi say
SIG_ADDTOOFFSET(+3),
SIG_MAGICDWORD,
0x7a, // push2
0x38, SIG_UINT16(0x009b), // pushi 155d
0x39, 0x1d, // pushi 29d (bat message)
SIG_ADDTOOFFSET(+7),
0x4a, SIG_UINT16(0x0010), // send 16d (say: 2 155 29 1 self 640)
PATCH_END
};

static const uint16 qfg4UpperPeerBatsCDPatch2[] = {
0x38, PATCH_SELECTOR16(changeState), // pushi changeState
0x78, // push1
0x76, // push0
0x72, PATCH_UINT16(0x0176), // lofsa sCloseSecretDoor
0x4a, PATCH_UINT16(0x0006), // send 6d (call the rewritten method)
0x38, PATCH_SELECTOR16(cue), // pushi cue
0x76, // push0
0x54, PATCH_UINT16(0x0004), // self 4d (self-cue)
0x35, 0x00, // ldi 0 (waste 2 bytes)
0x35, 0x00, // ldi 0 (waste 2 bytes)
PATCH_END
};

// Applies to at least: English floppy, German floppy
static const uint16 qfg4UpperPeerBatsFloppySignature2[] = {
0x38, SIG_SELECTOR16(say), // pushi say
SIG_ADDTOOFFSET(+3),
SIG_MAGICDWORD,
0x7a, // push2
0x38, SIG_UINT16(0x009b), // pushi 155d
0x39, 0x1d, // pushi 29d (bat message)
SIG_ADDTOOFFSET(+7),
0x4a, SIG_UINT16(0x0010), // send 16d (say: 2 155 29 1 self 640)
PATCH_END
};

static const uint16 qfg4UpperPeerBatsFloppyPatch2[] = {
0x38, PATCH_SELECTOR16(changeState), // pushi changeState
0x78, // push1
0x76, // push0
0x72, PATCH_UINT16(0x0160), // lofsa sCloseSecretDoor
0x4a, PATCH_UINT16(0x0006), // send 6d (call the rewritten method)
0x38, PATCH_SELECTOR16(cue), // pushi cue
0x76, // push0
0x54, PATCH_UINT16(0x0004), // self 4d (self-cue)
0x35, 0x00, // ldi 0 (waste 2 bytes)
0x35, 0x00, // ldi 0 (waste 2 bytes)
PATCH_END
};

// In the room (644) connected to the lower door of the bat-infested stairway,
// peering through the keyhole *always* reports bats.
//
// As you kill the bats, global plot flags are set. Normally flags 331-334
// would be checked via proc0_4(). They're in a bitmask, among other flags, so
// we can check all simultaneously (0000000000011110).
//
// global[520] & 30 == 30
//
// Room 644 has an IF-ELSE deciding between largely redundant calls to
// gloryMessager::say(). We make room by combining them.
//
// Applies to at least: English CD, English floppy, German floppy
// Responsible method: sPeepingTom::changeState(1) in script 644
// Fixes bug: #10789
static const uint16 qfg4LowerPeerBatsSignature[] = {
SIG_MAGICDWORD,
0x78, // push1 x (check if hero's near the left door)
0x76, // push0
0x81, 0x00, // lag global[0] (hero)
0x4a, SIG_UINT16(0x0004), // send 4d
0x36, // push
0x35, 0x3c, // ldi 60d
0x22, // lt?
0x31, 0x18, // bnt 24d [else right door w/ bats]
0x38, SIG_SELECTOR16(say), // pushi say (left door, generic message)
SIG_ADDTOOFFSET(+14), // ...
0x81, 0x5b, // lag global[91] (gloryMessager)
0x4a, SIG_UINT16(0x0010), // send 16d (say: 2 155 27 1 self 640)
0x33, SIG_ADDTOOFFSET(+1), // jmp [end the case]
SIG_ADDTOOFFSET(+22), // (right door, say(), 3rd arg is 29 for bat message)
0x33, SIG_ADDTOOFFSET(+1), // jmp [end the case]
SIG_END
};

static const uint16 qfg4LowerPeerBatsPatch[] = {
0x38, PATCH_SELECTOR16(say), // pushi say (decide the message as args are stacked up)
0x39, 0x06, // pushi 6d
0x7a, // push2
0x38, PATCH_UINT16(0x009b), // pushi 155d

0x78, // push1 x (check if left door)
0x76, // push0
0x81, 0x00, // lag global[0] (hero)
0x4a, PATCH_UINT16(0x0004), // send 4d
0x36, // push
0x35, 0x3c, // ldi 60d
0x22, // lt?
0x31, 0x04, // bnt 4d [after this jmp]
0x39, 0x1b, // pushi 27d (left door, generic message)
0x33, 0x10, // jmp 16d [after deciding message]

0x39, 0x1e, // pushi 30d (stack up for eq)
0x3c, // dup (stack up another for AND)
0x80, PATCH_UINT16(0x0208), // lag global[520] (plot flags bitmask)
0x12, // and
0x1a, // eq? (Were all dead bat flags set?)
0x2f, 0x04, // bt 4d [after this jmp]
0x39, 0x1d, // pushi 29d (right door, bat message)
0x33, 0x02, // jmp 2d [after deciding message]

0x39, 0x1b, // pushi 27d (right door, killed all bats, generic message)

0x78, // push1
0x7c, // pushSelf
0x38, PATCH_UINT16(0x0280), // pushi 640d
0x81, 0x5b, // lag global[91] (gloryMessager)
0x4a, PATCH_UINT16(0x0010), // send 16d
0x33, PATCH_GETORIGINALBYTEADJUST(60, +7), // jmp [end the case]
PATCH_END
};

// The castle's great hall (630) has a doorMat region that intermittently sends
// hero back to the room they just left (barrel room) the instant they arrive.
//
Expand Down Expand Up @@ -10508,10 +10696,14 @@ static const SciScriptPatcherEntry qfg4Signatures[] = {
{ true, 643, "fix iron safe's east door sending hero west", 1, qfg4SafeDoorEastSignature, qfg4SafeDoorEastPatch },
{ true, 643, "fix iron safe's door oil flags", 1, qfg4SafeDoorOilSignature, qfg4SafeDoorOilPatch },
{ true, 644, "fix castle door open message for rogue", 2, qfg4StuckDoorSignature, qfg4StuckDoorPatch },
{ true, 644, "fix peer bats, lower door", 1, qfg4LowerPeerBatsSignature, qfg4LowerPeerBatsPatch },
{ true, 645, "fix extraneous door sound in the castle", 1, qfg4DoubleDoorSoundSignature, qfg4DoubleDoorSoundPatch },
{ false, 663, "CD: fix crest bookshelf", 1, qfg4CrestBookshelfCDSignature, qfg4CrestBookshelfCDPatch },
{ false, 663, "CD: fix crest bookshelf", 1, qfg4CrestBookshelfCDSignature, qfg4CrestBookshelfCDPatch },
{ false, 663, "Floppy: fix crest bookshelf", 1, qfg4CrestBookshelfFloppySignature, qfg4CrestBookshelfFloppyPatch },
{ true, 663, "CD/Floppy: fix crest bookshelf motion", 1, qfg4CrestBookshelfMotionSignature, qfg4CrestBookshelfMotionPatch },
{ true, 663, "CD/Floppy: fix peer bats, upper door (1/2)", 1, qfg4UpperPeerBatsSignature1, qfg4UpperPeerBatsPatch1 },
{ false, 663, "CD: fix peer bats, upper door (2/2)", 1, qfg4UpperPeerBatsCDSignature2, qfg4UpperPeerBatsCDPatch2 },
{ false, 663, "Floppy: fix peer bats, upper door (2/2)", 1, qfg4UpperPeerBatsFloppySignature2, qfg4UpperPeerBatsFloppyPatch2 },
{ true, 710, "fix tentacle wriggle cycler", 1, qfg4TentacleWriggleSignature, qfg4TentacleWrigglePatch },
{ true, 710, "fix tentacle retraction for fighter", 1, qfg4PitRopeFighterSignature, qfg4PitRopeFighterPatch },
{ true, 710, "fix tentacle retraction for mage (1/2)", 1, qfg4PitRopeMageSignature1, qfg4PitRopeMagePatch1 },
Expand Down Expand Up @@ -12370,9 +12562,11 @@ void ScriptPatcher::processScript(uint16 scriptNr, SciSpan<byte> scriptData) {
// Similar signatures that patch with different addresses/offsets
enablePatch(signatureTable, "CD: fix guild tunnel access (3/3)");
enablePatch(signatureTable, "CD: fix crest bookshelf");
enablePatch(signatureTable, "CD: fix peer bats, upper door (2/2)");
} else {
enablePatch(signatureTable, "Floppy: fix guild tunnel access (3/3)");
enablePatch(signatureTable, "Floppy: fix crest bookshelf");
enablePatch(signatureTable, "Floppy: fix peer bats, upper door (2/2)");
}
break;
default:
Expand Down

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