SCI: Add a hack in kGetAngleWorker to fix bug #3540976

kGetAngle(Worker) has been implemented based on behavior observed
with a test program created with SCI Studio. However, the return values
have subtle differences from the original, which uses atan(). This
temporary hack will do for now till the implementation of kGetAngle is
done again. A simpler atan2-based implementation has also been added for
future reference

1 files changed, 19 insertions, 0 deletions

diff --git a/engines/sci/engine/kmath.cpp b/engines/sci/engine/kmath.cpp
index 7570856dff..cbfe00d3ca 100644
--- a/engines/sci/engine/kmath.cpp
+++ b/engines/sci/engine/kmath.cpp
@@ -78,6 +78,25 @@ reg_t kSqrt(EngineState *s, int argc, reg_t *argv) {
 }
 
 uint16 kGetAngleWorker(int16 x1, int16 y1, int16 x2, int16 y2) {
+	// TODO: This has been implemented based on behavior observed with a test
+	// program created with SCI Studio. However, the return values have subtle
+	// differences from the original, which uses atan().
+	// The differences in the return values are the cause of bug #3540976
+	// and perhaps bug #3037267 as well.
+
+	// HACK: Return the expected value for Longbow, scene 150 (bug #3540976).
+	// This is a temporary solution, till the function returns the expected
+	// results.
+	if (g_sci->getGameId() == GID_LONGBOW && g_sci->getEngineState()->currentRoomNumber() == 150) {
+		if (x1 == 207 && y1 == 88 && x2 == 107 && y2 == 184)
+			return 226;
+	}
+
+#if 0
+	// A simpler atan2-based implementation
+	return (360 - atan2((double)(x1 - x2), (double)(y1 - y2)) * 57.2958) % 360;
+#endif
+
 	int16 xRel = x2 - x1;
 	int16 yRel = y1 - y2; // y-axis is mirrored.
 	int16 angle;