SCI: Stop EngineState::wait mutating r_acc

This wait function is used by kernel calls other than kWait, and
those other functions do not mutate r_acc in SSCI.

3 files changed, 6 insertions, 5 deletions

diff --git a/engines/sci/engine/kgraphics.cpp b/engines/sci/engine/kgraphics.cpp
index 9bfeb9ab01..28e054bea9 100644
--- a/engines/sci/engine/kgraphics.cpp
+++ b/engines/sci/engine/kgraphics.cpp
@@ -397,13 +397,13 @@ reg_t kTextSize(EngineState *s, int argc, reg_t *argv) {
 reg_t kWait(EngineState *s, int argc, reg_t *argv) {
 	int sleep_time = argv[0].toUint16();
 
-	s->wait(sleep_time);
+	const int delta = s->wait(sleep_time);
 
 	if (g_sci->_guestAdditions->kWaitHook()) {
 		return NULL_REG;
 	}
 
-	return s->r_acc;
+	return make_reg(0, delta);
 }
 
 reg_t kCoordPri(EngineState *s, int argc, reg_t *argv) {
diff --git a/engines/sci/engine/state.cpp b/engines/sci/engine/state.cpp
index 731f6b7e07..343a9496b3 100644
--- a/engines/sci/engine/state.cpp
+++ b/engines/sci/engine/state.cpp
@@ -136,13 +136,14 @@ void EngineState::speedThrottler(uint32 neededSleep) {
 	}
 }
 
-void EngineState::wait(int16 ticks) {
+int EngineState::wait(int16 ticks) {
 	uint32 time = g_system->getMillis();
-	r_acc = make_reg(0, ((long)time - (long)lastWaitTime) * 60 / 1000);
+	const int tickDelta = ((long)time - (long)lastWaitTime) * 60 / 1000;
 	lastWaitTime = time;
 
 	ticks *= g_debug_sleeptime_factor;
 	g_sci->sleep(ticks * 1000 / 60);
+	return tickDelta;
 }
 
 void EngineState::initGlobals() {
diff --git a/engines/sci/engine/state.h b/engines/sci/engine/state.h
index b02ace8aaf..21c9a1fe9a 100644
--- a/engines/sci/engine/state.h
+++ b/engines/sci/engine/state.h
@@ -126,7 +126,7 @@ public:
 	uint32 _screenUpdateTime;	/**< The last time the game updated the screen */
 
 	void speedThrottler(uint32 neededSleep);
-	void wait(int16 ticks);
+	int wait(int16 ticks);
 
 #ifdef ENABLE_SCI32
 	uint32 _eventCounter; /**< total times kGetEvent was invoked since the last call to kFrameOut */