[Scummvm-git-logs] scummvm master -> f7058856c614e5b5b4df37b71b08854d865d0a17
sluicebox
22204938+sluicebox at users.noreply.github.com
Mon Jul 19 00:35:46 UTC 2021
This automated email contains information about 1 new commit which have been
pushed to the 'scummvm' repo located at https://github.com/scummvm/scummvm .
Summary:
f7058856c6 SCI: Fix KQ6 bugs when clicking Features too quickly
Commit: f7058856c614e5b5b4df37b71b08854d865d0a17
https://github.com/scummvm/scummvm/commit/f7058856c614e5b5b4df37b71b08854d865d0a17
Author: sluicebox (22204938+sluicebox at users.noreply.github.com)
Date: 2021-07-18T19:33:13-05:00
Commit Message:
SCI: Fix KQ6 bugs when clicking Features too quickly
Replaces a room-specific script patch with a generic one that should
fix the bug wherever it occurs. At the time, it wasn't known if this
could occur in other parts of the game under ScummVM, and so patching
the only known symptom was safer.
Changed paths:
engines/sci/engine/script_patches.cpp
diff --git a/engines/sci/engine/script_patches.cpp b/engines/sci/engine/script_patches.cpp
index f10330fdba..2297ad5c0a 100644
--- a/engines/sci/engine/script_patches.cpp
+++ b/engines/sci/engine/script_patches.cpp
@@ -5718,70 +5718,6 @@ static const uint16 kq6PatchTruncatedMessagesFix[] = {
PATCH_END
};
-// Clicking Look or Do on the secret passage peephole outside of Cassima's room
-// multiple times can lockup the game and crash the original.
-//
-// The bug is in the Feature and CueObj classes but room 800 and cassimaScript
-// happen to expose it. Clicking on a Feature such as the hole causes ego to
-// walk towards it, then face it, wait three cycles, and then call doVerb.
-// Feature:handleEvent calls ego:setMotion and then has CueObj orchestrate the
-// rest of the sequence. If ego is instead already within approachDist and
-// facing the clicked Feature then handleEvent sets CueObj to its final state
-// so that doVerb is called immediately. handleEvent resets CueObj's state and
-// stops any ego movement to prevent a conflict from an earlier call but it
-// doesn't stop ego's looper from turning to face the Feature. Clicking on a
-// Feature while ego is within approachDist and in the process of turning to
-// face that Feature from a previous click causes both clicks to generate calls
-// to doVerb, and out of order. In room 800 that causes cassimaScript to run a
-// a second time and interrupt the first which breaks the game in various ways.
-//
-// We fix room 800 by adding a check to prevent running a peephole script if
-// there's already a script running.
-//
-// Applies to: All versions
-// Responsible method: chink:doVerb
-static const uint16 kq6SignatureCassimaSecretPassage[] = {
- SIG_MAGICDWORD,
- 0x67, 0x1a, // pTos noun
- 0x3c, // dup
- 0x35, 0x04, // ldi 04
- 0x1a, // eq?
- 0x31, 0x12, // bnt 12
- 0x38, SIG_SELECTOR16(setScript), // pushi setScript
- 0x78, // push1
- 0x78, // push1
- 0x38, SIG_UINT16(0x0321), // pushi 0321
- 0x43, 0x02, 0x02, // callk ScriptID 02 [ ScriptID 801 ]
- 0x36, // push
- 0x81, 0x02, // lag 02
- 0x4a, 0x06, // send 06 [ rm800 setScript: cassimaScript ]
- 0x33, 0x10, // jmp 10
- 0x38, SIG_SELECTOR16(setScript), // pushi setScript
- SIG_ADDTOOFFSET(+5),
- 0x43, 0x02, 0x02, // callk ScriptID 02 [ ScriptID 802 ]
- SIG_END
-};
-
-static const uint16 kq6PatchCassimaSecretPassage[] = {
- 0x38, PATCH_SELECTOR16(script), // pushi script
- 0x76, // push0
- 0x81, 0x02, // lag 02
- 0x4a, 0x04, // send 04 [ rm800 script? ]
- 0x31, 0x01, // bnt 01
- 0x48, // ret [ do nothing if script is running ]
- 0x67, 0x1a, // pTos noun
- 0x3c, // dup
- 0x35, 0x04, // ldi 04
- 0x1a, // eq?
- 0x38, PATCH_SELECTOR16(setScript), // pushi setScript
- 0x31, 0x07, // bnt 07
- 0x78, // push1
- 0x78, // push1
- 0x38, PATCH_UINT16(0x0321), // pushi 0321
- 0x33, 0x05, // jmp 05 [ callk ScriptID 02 ]
- PATCH_END
-};
-
// WORKAROUND
//
// Dangling Participle and Rotten Tomato are inventory items that can talk, but
@@ -6460,6 +6396,44 @@ static const uint16 kq6PatchGuardDogMusic[] = {
PATCH_END
};
+// Quickly clicking on certain Features multiple times can lockup and crash the
+// the game. Examples: giving the rose to Beauty and looking at the peephole in
+// the passage outside of Cassima's room. This also occurs in the original.
+//
+// The bug is in the Feature and CueObj classes but only a few Features are
+// vulnerable. Factors include approach properties (coordinates, dist), the
+// surrounding obstacles, and timing. Clicking on a Feature causes ego to walk
+// towards it, turn towards it, wait three cycles, and then call doVerb. CueObj
+// handles most of this sequence. However, if ego is already close to the
+// Feature, then CueObj is advanced to its final state to immediately call
+// doVerb. The problem is that this doesn't take into account that ego might be
+// in the middle of turning. If a second click occurs while ego is turning from
+// the first click, doVerb will be called immediately, CueObj will be reset to
+// its initial state, and then ego's turn will complete and CueObj will proceed
+// to call doVerb again. If doVerb runs a hands-off script then it will be
+// interrupted and restarted at which point the game breaks in various ways.
+//
+// We fix this by removing a simple line that resets CueObj to its initial state
+// after it calls Feature:doVerb. Nothing depends on this; every caller resets
+// CueObj:state explicitly. But without this line, a stray cue from ego turning
+// will advance CueObj from its final state (three) to an unused state (four)
+// where it will have no effect. Although this buggy Feature script is in other
+// games, so far it's only known to cause problems in KQ6.
+//
+// Applies to: All versions
+// Responsible method: CueObj:changeState(3)
+static const uint16 kq6SignatureFeatureEventHandling[] = {
+ SIG_MAGICDWORD,
+ 0x35, 0x00, // ldi 00
+ 0x65, 0x14, // atop state [ state = 0 ]
+ SIG_END
+};
+
+static const uint16 kq6PatchFeatureEventHandling[] = {
+ 0x33, 0x02, // jmp 02 [ don't reset CueObj state ]
+ PATCH_END
+};
+
// script, description, signature patch
static const SciScriptPatcherEntry kq6Signatures[] = {
{ true, 52, "CD: Girl In The Tower playback", 1, kq6CDSignatureGirlInTheTowerPlayback, kq6CDPatchGirlInTheTowerPlayback },
@@ -6479,12 +6453,12 @@ static const SciScriptPatcherEntry kq6Signatures[] = {
{ true, 481, "fix duplicate baby tears point", 1, kq6SignatureDuplicateBabyTearsPoint, kq6PatchDuplicateBabyTearsPoint },
{ true, 640, "fix 'Tickets Only' audio timing", 1, kq6CDSignatureTicketsOnlyAudioTiming, kq6CDPatchTicketsOnlyAudioTiming },
{ true, 745, "fix wedding genie lamp message", 1, kq6SignatureWeddingGenieLampMessage, kq6PatchWeddingGenieLampMessage },
- { true, 800, "fix Cassima secret passage peephole", 1, kq6SignatureCassimaSecretPassage, kq6PatchCassimaSecretPassage },
{ true, 907, "fix inventory stack leak", 1, kq6SignatureInventoryStackFix, kq6PatchInventoryStackFix },
{ true, 907, "fix hair detection for ribbon's look msg", 1, kq6SignatureLookRibbonFix, kq6PatchLookRibbonFix },
{ true, 907, "talking inventory workaround", 4, kq6SignatureTalkingInventory, kq6PatchTalkingInventory },
{ true, 924, "CD/Mac: fix truncated messages", 1, kq6SignatureTruncatedMessagesFix, kq6PatchTruncatedMessagesFix },
{ true, 928, "Narrator lockup fix", 1, sciNarratorLockupSignature, sciNarratorLockupPatch },
+ { true, 950, "fix Feature event handling", 1, kq6SignatureFeatureEventHandling, kq6PatchFeatureEventHandling },
// King's Quest 6 and Laura Bow 2 share basic patches for audio + text support
// *** King's Quest 6 audio + text support ***
{ false, 924, "CD: audio + text support KQ6&LB2 1", 1, kq6laurabow2CDSignatureAudioTextSupport1, kq6laurabow2CDPatchAudioTextSupport1 },
@@ -6939,7 +6913,7 @@ static const uint16 kq7InitGameGlobalsPatch[] = {
PATCH_ADDTOOFFSET(+0x35),
0xa0, PATCH_UINT16(0x014a), // sag 014a [ global330 = -1 ]
0xa0, PATCH_UINT16(0x0174), // sag 0174 [ global372 = -1 (reset chicken little) ]
- 0x34, PATCH_UINT16(0x7fe8), // ldi 7feg
+ 0x34, PATCH_UINT16(0x7fe8), // ldi 7fe8
0xa0, PATCH_UINT16(0x0142), // sag 0142 [ global332 = kMemoryInfo 0 result ]
0x33, 0x2c, // jmp 2c [ continue room init ]
// init loop
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