diff --git a/scumm/akos.cpp b/scumm/akos.cpp
index 6e27eaf66a1..cc588cc1b27 100644
--- a/scumm/akos.cpp
+++ b/scumm/akos.cpp
@@ -319,7 +319,7 @@ void AkosRenderer::codec1_genericDecode()
 
 				if (v1.scaletable[v1.tmp_x] < scale_x) {
 					v1.x += v1.scaleXstep;
-					if (v1.x >= _vm->_realWidth)
+					if (v1.x < 0 || v1.x >= _vm->_realWidth)
 						return;
 					maskbit = revBitMask[v1.x & 7];
 					v1.destptr += v1.scaleXstep;
@@ -387,7 +387,7 @@ void AkosRenderer::codec1_spec1()
 
 				if (v1.scaletable[v1.tmp_x] < scale_x) {
 					v1.x += v1.scaleXstep;
-					if (v1.x >= _vm->_realWidth)
+					if (v1.x < 0 || v1.x >= _vm->_realWidth)
 						return;
 					maskbit = revBitMask[v1.x & 7];
 					v1.destptr += v1.scaleXstep;
@@ -463,7 +463,7 @@ void AkosRenderer::codec1_spec3()
 
 				if (v1.scaletable[v1.tmp_x] < scale_x) {
 					v1.x += v1.scaleXstep;
-					if (v1.x >= _vm->_realWidth)
+					if (v1.x < 0 || v1.x >= _vm->_realWidth)
 						return;
 					maskbit = revBitMask[v1.x & 7];
 					v1.destptr += v1.scaleXstep;
diff --git a/scumm/costume.cpp b/scumm/costume.cpp
index 245d6a6ec5c..256725a7fa0 100644
--- a/scumm/costume.cpp
+++ b/scumm/costume.cpp
@@ -584,7 +584,7 @@ void CostumeRenderer::proc3()
 				_scaleIndexX = t + _scaleIndexXStep;
 				if (cost_scaleTable[t] < _scaleX) {
 					_xpos += _scaleIndexXStep;
-					if (_xpos >= _vm->_realWidth)
+					if (_xpos < 0 || _xpos >= _vm->_realWidth)
 						return;
 					maskbit = revBitMask[_xpos & 7];
 					_backbuff_ptr += _scaleIndexXStep;
@@ -646,7 +646,7 @@ void CostumeRenderer::proc2()
 				_scaleIndexX = t + _scaleIndexXStep;
 				if (cost_scaleTable[t] < _scaleX) {
 					_xpos += _scaleIndexXStep;
-					if (_xpos >= _vm->_realWidth)
+					if (_xpos < 0 || _xpos >= _vm->_realWidth)
 						return;
 					maskbit = revBitMask[_xpos & 7];
 					_backbuff_ptr += _scaleIndexXStep;
@@ -707,7 +707,7 @@ void CostumeRenderer::proc1()
 				_scaleIndexX = t + _scaleIndexXStep;
 				if (cost_scaleTable[t] < _scaleX) {
 					_xpos += _scaleIndexXStep;
-					if (_xpos >= _vm->_realWidth)
+					if (_xpos < 0 || _xpos >= _vm->_realWidth)
 						return;
 					_backbuff_ptr += _scaleIndexXStep;
 				}
@@ -1180,7 +1180,7 @@ void CostumeRenderer::proc_special(Actor *a, byte mask2)
 				_scaleIndexX = t + _scaleIndexXStep;
 				if (cost_scaleTable[t] < _scaleX) {
 					_xpos += _scaleIndexXStep;
-					if (_xpos >= _vm->_realWidth)
+					if (_xpos < 0 || _xpos >= _vm->_realWidth)
 						return;
 					maskbit = revBitMask[_xpos & 7];
 					_backbuff_ptr += _scaleIndexXStep;