From 57084b4a1b23e131be7497c4c97c75db060210c9 Mon Sep 17 00:00:00 2001
From: Colin Snover
Date: Wed, 29 Nov 2017 19:36:28 -0600
Subject: SCUMM: Fix UB shifting negative integers in Actor

---
 engines/scumm/actor.cpp | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

(limited to 'engines/scumm')

diff --git a/engines/scumm/actor.cpp b/engines/scumm/actor.cpp
index e3f93e5c97..f48f0ba46b 100644
--- a/engines/scumm/actor.cpp
+++ b/engines/scumm/actor.cpp
@@ -565,13 +565,13 @@ int Actor::actorWalkStep() {
 				_pos.y -= 1;
 		}
 	} else {
-		tmpX = (_pos.x << 16) + _walkdata.xfrac + (_walkdata.deltaXFactor >> 8) * _scalex;
+		tmpX = (_pos.x * (1 << 16)) + _walkdata.xfrac + (_walkdata.deltaXFactor / 256) * _scalex;
 		_walkdata.xfrac = (uint16)tmpX;
-		_pos.x = (tmpX >> 16);
+		_pos.x = (tmpX / (1 << 16));
 
-		tmpY = (_pos.y << 16) + _walkdata.yfrac + (_walkdata.deltaYFactor >> 8) * _scaley;
+		tmpY = (_pos.y * (1 << 16)) + _walkdata.yfrac + (_walkdata.deltaYFactor / 256) * _scaley;
 		_walkdata.yfrac = (uint16)tmpY;
-		_pos.y = (tmpY >> 16);
+		_pos.y = (tmpY / (1 << 16));
 	}
 
 	if (ABS(_pos.x - _walkdata.cur.x) > distX) {
-- 
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