XEEN: Initial bugfixes for map loading and fix draw list positions

5 files changed, 77 insertions, 77 deletions

diff --git a/engines/xeen/interface.cpp b/engines/xeen/interface.cpp
index deb8761b06..4550dac6d8 100644
--- a/engines/xeen/interface.cpp
+++ b/engines/xeen/interface.cpp
@@ -542,7 +542,7 @@ void Interface::draw3d(bool updateFlag) {
 	Map &map = *_vm->_map;
 	Screen &screen = *_vm->_screen;
 
-	if (!screen._windows[11]._enabled)
+	if (screen._windows[11]._enabled)
 		return;
 
 	_flipUIFrame = (_flipUIFrame + 1) % 4;
diff --git a/engines/xeen/interface.h b/engines/xeen/interface.h
index 4667592b20..df06f5d86b 100644
--- a/engines/xeen/interface.h
+++ b/engines/xeen/interface.h
@@ -101,9 +101,6 @@ private:
 
 	void updateAutoMap();
 public:
-	OutdoorDrawList _outdoorList;
-	IndoorDrawList _indoorList;
-public:
 	Interface(XeenEngine *vm);
 
 	void setup();
diff --git a/engines/xeen/interface_map.cpp b/engines/xeen/interface_map.cpp
index af52178ba1..cc99b3ee86 100644
--- a/engines/xeen/interface_map.cpp
+++ b/engines/xeen/interface_map.cpp
@@ -56,31 +56,31 @@ OutdoorDrawList::OutdoorDrawList() : _skySprite(_data[1]), _groundSprite(_data[2
 	_data[25] = DrawStruct(0, 8, 109);
 	_data[26] = DrawStruct(0, 201, 109);
 	_data[27] = DrawStruct(0, 8, 109);
-	_data[28] = DrawStruct(1, 65472, 61, 14, SPRFLAG_2000);
-	_data[29] = DrawStruct(1, 65496, 61, 14, 0);
-	_data[30] = DrawStruct(1, 65520, 61, 14, 0);
+	_data[28] = DrawStruct(1, -64, 61, 14, SPRFLAG_2000);
+	_data[29] = DrawStruct(1, -40, 61, 14, 0);
+	_data[30] = DrawStruct(1, -16, 61, 14, 0);
 	_data[31] = DrawStruct(1, 8, 61, 14, 0);
 	_data[32] = DrawStruct(1, 128, 61, 14, SPRFLAG_HORIZ_FLIPPED | SPRFLAG_2000);
 	_data[33] = DrawStruct(1, 104, 61, 14, SPRFLAG_HORIZ_FLIPPED);
 	_data[34] = DrawStruct(1, 80, 61, 14, SPRFLAG_HORIZ_FLIPPED);
 	_data[35] = DrawStruct(1, 56, 61, 14, SPRFLAG_HORIZ_FLIPPED);
 	_data[36] = DrawStruct(1, 32, 61, 14, 0);
-	_data[37] = DrawStruct(0, 65527, 61, 14, 0);
-	_data[38] = DrawStruct(0, 65478, 61, 14, 0);
+	_data[37] = DrawStruct(0, -9, 61, 14, 0);
+	_data[38] = DrawStruct(0, -58, 61, 14, 0);
 	_data[39] = DrawStruct(0, 40, 61, 14, 0);
-	_data[40] = DrawStruct(0, 65454, 61, 14, 0);
+	_data[40] = DrawStruct(0, -82, 61, 14, 0);
 	_data[41] = DrawStruct(0, 64, 61, 14, 0);
-	_data[42] = DrawStruct(0, 65495, 61, 14, 0);
-	_data[43] = DrawStruct(0, 65510, 61, 14, 0);
-	_data[44] = DrawStruct(0, 65502, 61, 14, 0);
-	_data[45] = DrawStruct(0, 65520, 61, 14, 0);
+	_data[42] = DrawStruct(0, -41, 61, 14, 0);
+	_data[43] = DrawStruct(0, -26, 61, 14, 0);
+	_data[44] = DrawStruct(0, -34, 61, 14, 0);
+	_data[45] = DrawStruct(0, -16, 61, 14, 0);
 	_data[46] = DrawStruct(0, 23, 61, 14, 0);
 	_data[47] = DrawStruct(0, 16, 61, 14, 0);
-	_data[48] = DrawStruct(0, 65478, 61, 14, 0);
+	_data[48] = DrawStruct(0, -58, 61, 14, 0);
 	_data[49] = DrawStruct(0, 40, 61, 14, 0);
-	_data[50] = DrawStruct(0, 65519, 61, 14, 0);
-	_data[51] = DrawStruct(0, 65535, 58, 14, 0);
-	_data[52] = DrawStruct(0, 65527, 58, 14, 0);
+	_data[50] = DrawStruct(0, -17, 61, 14, 0);
+	_data[51] = DrawStruct(0, -1, 58, 14, 0);
+	_data[52] = DrawStruct(0, -9, 58, 14, 0);
 	_data[53] = DrawStruct(0, 72, 58, 12, 0);
 	_data[54] = DrawStruct(0, 72, 58, 12, SPRFLAG_HORIZ_FLIPPED);
 	_data[55] = DrawStruct(0, 69, 63, 12, 0);
@@ -89,21 +89,21 @@ OutdoorDrawList::OutdoorDrawList() : _skySprite(_data[1]), _groundSprite(_data[2
 	_data[58] = DrawStruct(0, 71, 53, 12, SPRFLAG_HORIZ_FLIPPED);
 	_data[59] = DrawStruct(0, 80, 57, 12, 0);
 	_data[60] = DrawStruct(0, 64, 57, 12, SPRFLAG_HORIZ_FLIPPED);
-	_data[61] = DrawStruct(2, 65525, 54, 8, 0);
-	_data[62] = DrawStruct(1, 65515, 54, 11, 0);
+	_data[61] = DrawStruct(2, -11, 54, 8, 0);
+	_data[62] = DrawStruct(1, -21, 54, 11, 0);
 	_data[63] = DrawStruct(2, 165, 54, 8, SPRFLAG_HORIZ_FLIPPED);
 	_data[64] = DrawStruct(1, 86, 54, 11, SPRFLAG_HORIZ_FLIPPED);
 	_data[65] = DrawStruct(1, 33, 54, 11, 0);
-	_data[66] = DrawStruct(0, 65528, 54, 12, 0);
-	_data[67] = DrawStruct(0, 65463, 54, 12, 0);
+	_data[66] = DrawStruct(0, -8, 54, 12, 0);
+	_data[67] = DrawStruct(0, -73, 54, 12, 0);
 	_data[68] = DrawStruct(0, 57, 54, 12, 0);
-	_data[69] = DrawStruct(0, 65471, 54, 12, 0);
-	_data[70] = DrawStruct(0, 65455, 54, 12, 0);
+	_data[69] = DrawStruct(0, -65, 54, 12, 0);
+	_data[70] = DrawStruct(0, -81, 54, 12, 0);
 	_data[71] = DrawStruct(0, 49, 54, 12, 0);
 	_data[72] = DrawStruct(0, 65, 54, 12, 0);
-	_data[73] = DrawStruct(0, 65512, 54, 12, 0);
+	_data[73] = DrawStruct(0, -24, 54, 12, 0);
 	_data[74] = DrawStruct(0, 9, 50, 12, 0);
-	_data[75] = DrawStruct(0, 65528, 50, 12, 0);
+	_data[75] = DrawStruct(0, -8, 50, 12, 0);
 	_data[76] = DrawStruct(0, 72, 53, 8, 0);
 	_data[77] = DrawStruct(0, 72, 53, 8, SPRFLAG_HORIZ_FLIPPED);
 	_data[78] = DrawStruct(0, 77, 58, 8, 0);
@@ -115,14 +115,14 @@ OutdoorDrawList::OutdoorDrawList() : _skySprite(_data[1]), _groundSprite(_data[2
 	_data[84] = DrawStruct(2, 8, 40);
 	_data[85] = DrawStruct(2, 146, 40, 0, SPRFLAG_HORIZ_FLIPPED);
 	_data[86] = DrawStruct(1, 32, 40, 6, 0);
-	_data[87] = DrawStruct(0, 65529, 30, 7, 0);
-	_data[88] = DrawStruct(0, 65424, 30, 7, SPRFLAG_2000);
+	_data[87] = DrawStruct(0, -7, 30, 7, 0);
+	_data[88] = DrawStruct(0, -112, 30, 7, SPRFLAG_2000);
 	_data[89] = DrawStruct(0, 98, 30, 7, SPRFLAG_2000);
-	_data[90] = DrawStruct(0, 65424, 30, 8, SPRFLAG_2000);
+	_data[90] = DrawStruct(0, -112, 30, 8, SPRFLAG_2000);
 	_data[91] = DrawStruct(0, 98, 30, 8, SPRFLAG_2000);
-	_data[92] = DrawStruct(0, 65498, 30, 8, 0);
+	_data[92] = DrawStruct(0, -38, 30, 8, 0);
 	_data[93] = DrawStruct(0, 25, 30, 8, 0);
-	_data[94] = DrawStruct(0, 65529, 30, 8, 0);
+	_data[94] = DrawStruct(0, -7, 30, 8, 0);
 	_data[95] = DrawStruct(0, 72, 48, 4, 0);
 	_data[96] = DrawStruct(0, 72, 48, 4, SPRFLAG_HORIZ_FLIPPED);
 	_data[97] = DrawStruct(0, 85, 53, 4, 0);
@@ -134,22 +134,22 @@ OutdoorDrawList::OutdoorDrawList() : _skySprite(_data[1]), _groundSprite(_data[2
 	_data[103] = DrawStruct(0, 8, 24);
 	_data[104] = DrawStruct(0, 169, 24, 0, SPRFLAG_HORIZ_FLIPPED);
 	_data[105] = DrawStruct(1, 32, 24);
-	_data[106] = DrawStruct(0, 65513, 40, 0, SPRFLAG_2000);
+	_data[106] = DrawStruct(0, -23, 40, 0, SPRFLAG_2000);
 	_data[107] = DrawStruct(0, 200, 40, 0, SPRFLAG_HORIZ_FLIPPED | SPRFLAG_2000);
 	_data[108] = DrawStruct(0, 8, 47);
 	_data[109] = DrawStruct(0, 169, 47, 0, SPRFLAG_HORIZ_FLIPPED);
-	_data[110] = DrawStruct(1, 65480, 65532, 32768, SPRFLAG_4000 | SPRFLAG_2000);
-	_data[111] = DrawStruct(0, 65531, 2, 0, SPRFLAG_4000 | SPRFLAG_2000);
-	_data[112] = DrawStruct(0, 65469, 2, 0, SPRFLAG_4000 | SPRFLAG_2000);
+	_data[110] = DrawStruct(1, -56, -4, 0x8000, SPRFLAG_4000 | SPRFLAG_2000);
+	_data[111] = DrawStruct(0, -5, 2, 0, SPRFLAG_4000 | SPRFLAG_2000);
+	_data[112] = DrawStruct(0, -67, 2, 0, SPRFLAG_4000 | SPRFLAG_2000);
 	_data[113] = DrawStruct(0, 44, 73);
 	_data[114] = DrawStruct(0, 44, 73);
 	_data[115] = DrawStruct(0, 58, 14, 0, SPRFLAG_4000 | SPRFLAG_2000);
 	_data[116] = DrawStruct(0, 169, 73);
 	_data[117] = DrawStruct(0, 169, 73);
-	_data[118] = DrawStruct(0, 65531, 14, 0, SPRFLAG_4000 | SPRFLAG_2000);
+	_data[118] = DrawStruct(0, -5, 14, 0, SPRFLAG_4000 | SPRFLAG_2000);
 	_data[119] = DrawStruct(0, 110, 73);
 	_data[120] = DrawStruct(0, 110, 73);
-	_data[121] = DrawStruct(0, 65531, 14, 0, SPRFLAG_4000 | SPRFLAG_2000);
+	_data[121] = DrawStruct(0, -5, 14, 0, SPRFLAG_4000 | SPRFLAG_2000);
 	_data[122] = DrawStruct(0, 110, 73);
 	_data[123] = DrawStruct(0, 110, 73);
 	_data[124] = DrawStruct(0, 72, 43);
@@ -232,31 +232,31 @@ IndoorDrawList::IndoorDrawList() :
 	_data[43] = DrawStruct(14, 152, 60);
 	_data[44] = DrawStruct(8, 176, 60);
 	_data[45] = DrawStruct(8, 200, 60);
-	_data[46] = DrawStruct(0, 65472, 61, 14, 0);
-	_data[47] = DrawStruct(0, 65496, 61, 14, 0);
-	_data[48] = DrawStruct(0, 65520, 61, 14, 0);
+	_data[46] = DrawStruct(0, -64, 61, 14, 0);
+	_data[47] = DrawStruct(0, -40, 61, 14, 0);
+	_data[48] = DrawStruct(0, -16, 61, 14, 0);
 	_data[49] = DrawStruct(0, 8, 61, 14, 0);
 	_data[50] = DrawStruct(0, 32, 61, 14, 0);
 	_data[51] = DrawStruct(0, 56, 61, 14, 0);
 	_data[52] = DrawStruct(0, 80, 61, 14, 0);
 	_data[53] = DrawStruct(0, 104, 61, 14, 0);
 	_data[54] = DrawStruct(0, 128, 61, 14, 0);
-	_data[55] = DrawStruct(0, 65527, 58, 14, 0);
-	_data[56] = DrawStruct(0, 65502, 58, 14, 0);
+	_data[55] = DrawStruct(0, -9, 58, 14, 0);
+	_data[56] = DrawStruct(0, -34, 58, 14, 0);
 	_data[57] = DrawStruct(0, 16, 58, 14, 0);
-	_data[58] = DrawStruct(0, 65478, 58, 14, 0);
+	_data[58] = DrawStruct(0, -58, 58, 14, 0);
 	_data[59] = DrawStruct(0, 40, 58, 14, 0);
-	_data[60] = DrawStruct(0, 65495, 58, 14, 0);
-	_data[61] = DrawStruct(0, 65510, 58, 14, 0);
-	_data[62] = DrawStruct(0, 65502, 58, 14, 0);
-	_data[63] = DrawStruct(0, 65520, 58, 14, 0);
+	_data[60] = DrawStruct(0, -41, 58, 14, 0);
+	_data[61] = DrawStruct(0, -26, 58, 14, 0);
+	_data[62] = DrawStruct(0, -34, 58, 14, 0);
+	_data[63] = DrawStruct(0, -16, 58, 14, 0);
 	_data[64] = DrawStruct(0, 23, 58, 14, 0);
 	_data[65] = DrawStruct(0, 16, 58, 14, 0);
-	_data[66] = DrawStruct(0, 65478, 58, 14, 0);
+	_data[66] = DrawStruct(0, -58, 58, 14, 0);
 	_data[67] = DrawStruct(0, 40, 58, 14, 0);
-	_data[68] = DrawStruct(0, 65519, 58, 14, 0);
-	_data[69] = DrawStruct(0, 65535, 58, 14, 0);
-	_data[70] = DrawStruct(0, 65527, 58, 14, 0);
+	_data[68] = DrawStruct(0, -17, 58, 14, 0);
+	_data[69] = DrawStruct(0, -1, 58, 14, 0);
+	_data[70] = DrawStruct(0, -9, 58, 14, 0);
 	_data[71] = DrawStruct(14, 8, 58);
 	_data[72] = DrawStruct(12, 8, 55);
 	_data[73] = DrawStruct(10, 32, 52);
@@ -273,26 +273,26 @@ IndoorDrawList::IndoorDrawList() :
 	_data[84] = DrawStruct(0, 71, 53, 12, SPRFLAG_HORIZ_FLIPPED);
 	_data[85] = DrawStruct(0, 80, 57, 12, 0);
 	_data[86] = DrawStruct(0, 64, 57, 12, SPRFLAG_HORIZ_FLIPPED);
-	_data[87] = DrawStruct(7, 65512, 52, 0, SPRFLAG_2000);
+	_data[87] = DrawStruct(7, -24, 52, 0, SPRFLAG_2000);
 	_data[88] = DrawStruct(7, 32, 52);
 	_data[89] = DrawStruct(7, 88, 52);
 	_data[90] = DrawStruct(0, 144, 52);
 	_data[91] = DrawStruct(0, 200, 52, 0, SPRFLAG_2000);
-	_data[92] = DrawStruct(0, 65457, 52, 11, SPRFLAG_2000);
-	_data[93] = DrawStruct(0, 65509, 52, 11, 0);
+	_data[92] = DrawStruct(0, -79, 52, 11, SPRFLAG_2000);
+	_data[93] = DrawStruct(0, -27, 52, 11, 0);
 	_data[94] = DrawStruct(0, 32, 52, 11, 0);
 	_data[95] = DrawStruct(0, 89, 52, 11, 0);
 	_data[96] = DrawStruct(0, 145, 52, 11, SPRFLAG_2000);
-	_data[97] = DrawStruct(0, 65528, 50, 12, 0);
-	_data[98] = DrawStruct(0, 65471, 50, 12, 0);
+	_data[97] = DrawStruct(0, -8, 50, 12, 0);
+	_data[98] = DrawStruct(0, -65, 50, 12, 0);
 	_data[99] = DrawStruct(0, 49, 50, 12, 0);
-	_data[100] = DrawStruct(0, 65471, 50, 12, 0);
-	_data[101] = DrawStruct(0, 65455, 50, 12, 0);
+	_data[100] = DrawStruct(0, -65, 50, 12, 0);
+	_data[101] = DrawStruct(0, -81, 50, 12, 0);
 	_data[102] = DrawStruct(0, 49, 50, 12, 0);
 	_data[103] = DrawStruct(0, 65, 50, 12, 0);
-	_data[104] = DrawStruct(0, 65512, 50, 12, 0);
+	_data[104] = DrawStruct(0, -24, 50, 12, 0);
 	_data[105] = DrawStruct(0, 9, 50, 12, 0);
-	_data[106] = DrawStruct(0, 65528, 50, 12, 0);
+	_data[106] = DrawStruct(0, -8, 50, 12, 0);
 	_data[107] = DrawStruct(7, 8, 48);
 	_data[108] = DrawStruct(7, 64, 40);
 	_data[109] = DrawStruct(6, 144, 40, 0, SPRFLAG_HORIZ_FLIPPED);
@@ -305,20 +305,20 @@ IndoorDrawList::IndoorDrawList() :
 	_data[116] = DrawStruct(0, 63, 47, 8, SPRFLAG_HORIZ_FLIPPED);
 	_data[117] = DrawStruct(0, 94, 52, 8, 0);
 	_data[118] = DrawStruct(0, 50, 52, 8, SPRFLAG_HORIZ_FLIPPED);
-	_data[119] = DrawStruct(6, 65496, 40, 0, SPRFLAG_2000);
+	_data[119] = DrawStruct(6, -40, 40, 0, SPRFLAG_2000);
 	_data[120] = DrawStruct(6, 64, 40);
 	_data[121] = DrawStruct(0, 168, 40, 0, SPRFLAG_2000);
-	_data[122] = DrawStruct(0, 65464, 40, 6, SPRFLAG_2000);
+	_data[122] = DrawStruct(0, -72, 40, 6, SPRFLAG_2000);
 	_data[123] = DrawStruct(0, 32, 40, 6, 0);
 	_data[124] = DrawStruct(0, 137, 40, 6, SPRFLAG_2000);
-	_data[125] = DrawStruct(0, 65529, 25, 7, 0);
-	_data[126] = DrawStruct(0, 65424, 25, 7, SPRFLAG_2000);
+	_data[125] = DrawStruct(0, -7, 25, 7, 0);
+	_data[126] = DrawStruct(0, -112, 25, 7, SPRFLAG_2000);
 	_data[127] = DrawStruct(0, 98, 25, 7, SPRFLAG_2000);
-	_data[128] = DrawStruct(0, 65424, 29, 8, SPRFLAG_2000);
+	_data[128] = DrawStruct(0, -112, 29, 8, SPRFLAG_2000);
 	_data[129] = DrawStruct(0, 98, 29, 8, SPRFLAG_2000);
-	_data[130] = DrawStruct(0, 65498, 29, 8, 0);
+	_data[130] = DrawStruct(0, -38, 29, 8, 0);
 	_data[131] = DrawStruct(0, 25, 29, 8, 0);
-	_data[132] = DrawStruct(0, 65529, 29, 8, 0);
+	_data[132] = DrawStruct(0, -7, 29, 8, 0);
 	_data[133] = DrawStruct(6, 32, 24);
 	_data[134] = DrawStruct(0, 168, 24, 0, SPRFLAG_HORIZ_FLIPPED);
 	_data[135] = DrawStruct(0, 72, 48, 4, 0);
@@ -329,23 +329,23 @@ IndoorDrawList::IndoorDrawList() :
 	_data[140] = DrawStruct(0, 55, 41, 4, SPRFLAG_HORIZ_FLIPPED);
 	_data[141] = DrawStruct(0, 106, 47, 4, 0);
 	_data[142] = DrawStruct(0, 38, 47, 4, SPRFLAG_HORIZ_FLIPPED);
-	_data[143] = DrawStruct(0, 65400, 24, 0, SPRFLAG_2000);
+	_data[143] = DrawStruct(0, -136, 24, 0, SPRFLAG_2000);
 	_data[144] = DrawStruct(0, 8, 12);
 	_data[145] = DrawStruct(0, 32, 24);
 	_data[146] = DrawStruct(0, 200, 12, 0, SPRFLAG_HORIZ_FLIPPED);
 	_data[147] = DrawStruct(0, 200, 24, 0, SPRFLAG_2000);
 	_data[148] = DrawStruct(0, 32, 24);
-	_data[149] = DrawStruct(0, 65531, 2, 0, SPRFLAG_4000 | SPRFLAG_2000);
-	_data[150] = DrawStruct(0, 65469, 10, 0, SPRFLAG_4000 | SPRFLAG_2000);
+	_data[149] = DrawStruct(0, -5, 2, 0, SPRFLAG_4000 | SPRFLAG_2000);
+	_data[150] = DrawStruct(0, -67, 10, 0, SPRFLAG_4000 | SPRFLAG_2000);
 	_data[151] = DrawStruct(0, 44, 73);
 	_data[152] = DrawStruct(0, 44, 73);
 	_data[153] = DrawStruct(0, 58, 14, 0, SPRFLAG_4000 | SPRFLAG_2000);
 	_data[154] = DrawStruct(0, 169, 73);
 	_data[155] = DrawStruct(0, 169, 73);
-	_data[156] = DrawStruct(0, 65531, 14, 0, SPRFLAG_4000 | SPRFLAG_2000);
+	_data[156] = DrawStruct(0, -5, 14, 0, SPRFLAG_4000 | SPRFLAG_2000);
 	_data[157] = DrawStruct(0, 110, 73);
 	_data[158] = DrawStruct(0, 110, 73);
-	_data[159] = DrawStruct(0, 65531, 14, 0, SPRFLAG_4000 | SPRFLAG_2000);
+	_data[159] = DrawStruct(0, -5, 14, 0, SPRFLAG_4000 | SPRFLAG_2000);
 	_data[160] = DrawStruct(0, 110, 73);
 	_data[161] = DrawStruct(0, 110, 73);
 	_data[162] = DrawStruct(0, 72, 43);
@@ -576,7 +576,8 @@ void InterfaceMap::drawIndoors() {
 		map.getCell(DRAW_NUMBERS[cellIndex]);
 
 		DrawStruct &drawStruct = _indoorList[3 + cellIndex];
-		drawStruct._sprites = &map._surfaceSprites[map._currentSurfaceId];
+		if (!map._surfaceSprites[map._currentSurfaceId].empty())
+			drawStruct._sprites = &map._surfaceSprites[map._currentSurfaceId];
 
 		surfaceId = map.mazeData()._surfaceTypes[map._currentSurfaceId];
 		if (surfaceId == 5 || surfaceId == 12) {
diff --git a/engines/xeen/map.cpp b/engines/xeen/map.cpp
index e410333d0d..507e4fc422 100644
--- a/engines/xeen/map.cpp
+++ b/engines/xeen/map.cpp
@@ -1157,9 +1157,10 @@ void Map::load(int mapId) {
 
 		indoorList._fwl_1F._sprites = &_wallSprites._fwl1;
 		indoorList._fwl_1F1R._sprites = &_wallSprites._fwl1;
-		indoorList._fwl_1F1L._sprites = &_wallSprites._fwl1;
-		
-		indoorList._horizon._sprites = &_groundSprites;
+		indoorList._fwl_1F1L._sprites = &_wallSprites._fwl1;		
+		indoorList._horizon._sprites = &_wallSprites._fwl1;
+
+		indoorList._ground._sprites = &_groundSprites;
 
 		// Down show horizon for certain maps
 		if (_vm->_files->_isDarkCc) {
diff --git a/engines/xeen/screen.cpp b/engines/xeen/screen.cpp
index 783f1ffbf4..7b6f972268 100644
--- a/engines/xeen/screen.cpp
+++ b/engines/xeen/screen.cpp
@@ -275,7 +275,8 @@ void Screen::update() {
 }
 
 void Screen::addDirtyRect(const Common::Rect &r) {
-	assert(r.isValidRect() && r.width() > 0 && r.height() > 0
+	assert(r.isValidRect() && r.width() > 0 && r.height() > 0 
+		&& r.left >= 0 && r.top >= 0
 		&& r.right <= SCREEN_WIDTH && r.bottom <= SCREEN_HEIGHT);
 	_dirtyRects.push_back(r);
 }