SCI: Fix PQ3 wrong ending

engines/sci/engine/script_patches.cpp

@@ -13488,6 +13488,40 @@ static const uint16 pq3PatchGiveLocketPoints[] = {
 	PATCH_END
 };
 
+// PQ3 plays the wrong ending if the player woke Marie from her coma but still
+//  has an extra rose in their inventory. Room 300 checks to see if Marie is
+//  awake by testing flags and item locations, but one of these tests is wrong
+//  and out of sync with similar tests in other scripts.
+//
+// Giving Marie the rose places it in her room, but purchasing a second rose
+//  changes rose:owner from her room back to ego, and the location check fails.
+//
+// We fix this by testing rose:state instead of rose:owner, as all the other
+//  scripts do. Sierra fixed this in later versions.
+//
+// Applies to: English PC VGA Floppy
+// Responsible method: rm300:init
+static const uint16 pq3SignatureWrongEnding[] = {
+	0x38, SIG_SELECTOR16(owner),         // pushi owner
+	0x76,                                // push0
+	0x39, SIG_MAGICDWORD,                // pushi at
+	      SIG_SELECTOR8(at),
+	0x78,                                // push1
+	0x39, 0x24,                          // pushi 24 [ rose ]
+	SIG_ADDTOOFFSET(+7),
+	0x35, 0x24,                          // ldi 24 [ hospital room ]
+	0x1a,                                // eq [ (rose owner:) == 36 ]
+	SIG_END
+};
+
+static const uint16 pq3PatchWrongEnding[] = {
+	0x38, PATCH_SELECTOR16(state),       // pushi state
+	PATCH_ADDTOOFFSET(+13),
+	0x35, 0x00,                          // ldi 00
+	0x1e,                                // gt? [ (rose state:) > 0 ]
+	PATCH_END
+};
+
 // The doctor's mouth moves too fast in room 36. doctorMouth:cyleSpeed is set to
 //  one, the maximum speed, unlike any other inset in the game. Most insets use
 //  the default speed of six and almost all the rest use an even slower speed.
@@ -13667,6 +13701,7 @@ static const SciScriptPatcherEntry pq3Signatures[] = {
 	{  true,    36, "doctor mouth speed",                     1, pq3SignatureDoctorMouthSpeed,      pq3PatchDoctorMouthSpeed },
 	{  true,    44, "fix judge evidence lockup",              1, pq3SignatureJudgeEvidenceLockup,   pq3PatchJudgeEvidenceLockup },
 	{  true,    99, "disable speed test",                     1, sci01SpeedTestLocalSignature,      sci01SpeedTestLocalPatch },
+	{  true,   300, "fix wrong ending",                       1, pq3SignatureWrongEnding,           pq3PatchWrongEnding },
 	{  true,   994, "NRS: remove speed throttle",             1, pq3SignatureNrsSpeedThrottle,      pq3PatchNrsSpeedThrottle },
 	SCI_SIGNATUREENTRY_TERMINATOR
 };