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SCI: Convert PQ2 speed workaround to script patch

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Cleans up kScriptID and speeds up startup
This commit is contained in:
sluicebox 2021-03-11 08:36:22 -08:00
parent a40c216236
commit 6853b5101f
2 changed files with 41 additions and 11 deletions
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11
engines/sci/engine/kscripts.cpp
View File

@ -287,17 +287,6 @@ reg_t kScriptID(EngineState *s, int argc, reg_t *argv) {
return NULL_REG;
const uint32 address = scr->validateExportFunc(index, true) + scr->getHeapOffset();
// WORKAROUND: Bugfix for the intro speed in PQ2 version 1.002.011.
// This is taken from the patch by NewRisingSun(NRS) / Belzorash. Global 3
// is used for timing during the intro, and in the problematic version it's
// initialized to 0, whereas it's 6 in other versions. Thus, we assign it
// to 6 here, fixing the speed of the introduction. Refer to bug #5496.
if (g_sci->getGameId() == GID_PQ2 && script == 200 &&
s->variables[VAR_GLOBAL][kGlobalVarSpeed].isNull()) {
s->variables[VAR_GLOBAL][kGlobalVarSpeed] = make_reg(0, 6);
}
return make_reg32(scriptSeg, address);
}

41
engines/sci/engine/script_patches.cpp
View File

@ -10788,6 +10788,44 @@ static const SciScriptPatcherEntry pq1vgaSignatures[] = {
SCI_SIGNATUREENTRY_TERMINATOR
};
// ===========================================================================
// Police Quest 2
// Starting in PQ2 1.002.011, the introduction runs too fast. The speed test was
// changed to run before the introduction but this introduced a bug where the
// game speed wasn't restored from the temporary fast speed used for the test.
//
// We fix this by restoring the game speed to the correct default value. Since
// we're patching the speed test anyway, we also disable it so that it returns
// the maximum value without delaying game startup.
//
// Applies to: All versions, although the speed bug is in 1.002.011 and later
// Responsible method: rm99:doit
// Fixes bug: #5496
static const uint16 pq2SignatureSpeedTest[] = {
SIG_MAGICDWORD,
0x8b, 0x00, // lsl 00
0x76, // push0
0x43, 0x46, 0x00, // callk GetTime 00
0x22, // lt?
0x30, // bnt [ skip exiting speed test ]
SIG_END
};
static const uint16 pq2PatchSpeedTest[] = {
0x34, PATCH_UINT16(0x7fff), // ldi 7fff
0xa1, 0x6e, // sag 6e [ speed test result = $7fff ]
0x34, PATCH_UINT16(0x0006), // ldi 0006
0xa1, 0x03, // sag 03 [ game speed = 6 ]
PATCH_END
};
// script, description, signature patch
static const SciScriptPatcherEntry pq2Signatures[] = {
{ true, 99, "speed test / intro speed", 1, pq2SignatureSpeedTest, pq2PatchSpeedTest },
SCI_SIGNATUREENTRY_TERMINATOR
};
// ===========================================================================
// Police Quest 3
@ -20973,6 +21011,9 @@ void ScriptPatcher::processScript(uint16 scriptNr, SciSpan<byte> scriptData) {
case GID_PQ1:
signatureTable = pq1vgaSignatures;
break;
case GID_PQ2:
signatureTable = pq2Signatures;
break;
case GID_PQ3:
signatureTable = pq3Signatures;
break;