SCI: adding workaround for camelot during ending

fixes bug #3044734
also fixing heap corruption during the ending

svn-id: r52077

6 files changed, 20 insertions, 1 deletions

diff --git a/engines/sci/engine/vm.cpp b/engines/sci/engine/vm.cpp
index 7c989e43f4..af4d4eb880 100644
--- a/engines/sci/engine/vm.cpp
+++ b/engines/sci/engine/vm.cpp
@@ -1800,7 +1800,10 @@ void run_vm(EngineState *s) {
 			// Load global, local, temp or param variable into the accumulator,
 			// using the accumulator as an additional index
 			var_type = opcode & 0x3; // Gets the variable type: g, l, t or p
-			var_number = opparams[0] + signed_validate_arithmetic(s->r_acc);
+			int16 value;
+			if (!validate_signedInteger(s->r_acc, value))
+				value = arithmetic_lookForWorkaround(opcode, opcodeLaiWorkarounds, s->r_acc, NULL_REG).offset;
+			var_number = opparams[0] + value;
 			s->r_acc = READ_VAR(var_type, var_number);
 			break;
 
diff --git a/engines/sci/engine/workarounds.cpp b/engines/sci/engine/workarounds.cpp
index fe269df563..ca47472ded 100644
--- a/engines/sci/engine/workarounds.cpp
+++ b/engines/sci/engine/workarounds.cpp
@@ -59,6 +59,12 @@ const SciWorkaroundEntry opcodeLeWorkarounds[] = {
 };
 
 //    gameID,           room,script,lvl,          object-name, method-name,    call,index,             workaround
+const SciWorkaroundEntry opcodeLaiWorkarounds[] = {
+	{ GID_CAMELOT,         92,   92,  0,     "endingCartoon2", "changeState", 0x20d,    0, { WORKAROUND_FAKE,   0 } }, // during the ending, sub gets called with no parameters, uses parameter 1 which is theGrail in this case - bug #3044734
+	SCI_WORKAROUNDENTRY_TERMINATOR
+};
+
+//    gameID,           room,script,lvl,          object-name, method-name,    call,index,             workaround
 const SciWorkaroundEntry opcodeLsiWorkarounds[] = {
 	{ GID_QFG2,           200,  200,  0,              "astro", "messages",       -1,    0, { WORKAROUND_FAKE,   0 } }, // when getting asked for your name by the astrologer bug #3039879
 	SCI_WORKAROUNDENTRY_TERMINATOR
diff --git a/engines/sci/engine/workarounds.h b/engines/sci/engine/workarounds.h
index 220ffd7fda..55a4b8f885 100644
--- a/engines/sci/engine/workarounds.h
+++ b/engines/sci/engine/workarounds.h
@@ -72,6 +72,7 @@ extern const SciWorkaroundEntry opcodeDivWorkarounds[];
 extern const SciWorkaroundEntry opcodeDptoaWorkarounds[];
 extern const SciWorkaroundEntry opcodeGeWorkarounds[];
 extern const SciWorkaroundEntry opcodeLeWorkarounds[];
+extern const SciWorkaroundEntry opcodeLaiWorkarounds[];
 extern const SciWorkaroundEntry opcodeLsiWorkarounds[];
 extern const SciWorkaroundEntry opcodeMulWorkarounds[];
 extern const SciWorkaroundEntry opcodeAndWorkarounds[];
diff --git a/engines/sci/graphics/paint16.cpp b/engines/sci/graphics/paint16.cpp
index 6e7da7c4dd..dbc738e2f7 100644
--- a/engines/sci/graphics/paint16.cpp
+++ b/engines/sci/graphics/paint16.cpp
@@ -417,6 +417,7 @@ void GfxPaint16::kernelGraphFrameBox(const Common::Rect &rect, int16 color) {
 }
 
 void GfxPaint16::kernelGraphDrawLine(Common::Point startPoint, Common::Point endPoint, int16 color, int16 priority, int16 control) {
+	_ports->clipLine(startPoint, endPoint);
 	_ports->offsetLine(startPoint, endPoint);
 	_screen->drawLine(startPoint.x, startPoint.y, endPoint.x, endPoint.y, color, priority, control);
 }
diff --git a/engines/sci/graphics/ports.cpp b/engines/sci/graphics/ports.cpp
index 32a9db5ae3..2d8bfde37d 100644
--- a/engines/sci/graphics/ports.cpp
+++ b/engines/sci/graphics/ports.cpp
@@ -566,6 +566,13 @@ void GfxPorts::offsetLine(Common::Point &start, Common::Point &end) {
 	end.y += _curPort->top;
 }
 
+void GfxPorts::clipLine(Common::Point &start, Common::Point &end) {
+	start.y = CLIP<int16>(start.y, _curPort->rect.top, _curPort->rect.bottom - 1);
+	start.x = CLIP<int16>(start.x, _curPort->rect.left, _curPort->rect.right - 1);
+	end.y = CLIP<int16>(end.y, _curPort->rect.top, _curPort->rect.bottom - 1);
+	end.x = CLIP<int16>(end.x, _curPort->rect.left, _curPort->rect.right - 1);
+}
+
 void GfxPorts::priorityBandsInit(int16 bandCount, int16 top, int16 bottom) {
 	int16 y;
 	int32 bandSize;
diff --git a/engines/sci/graphics/ports.h b/engines/sci/graphics/ports.h
index 42a0a5d4b4..453cb50986 100644
--- a/engines/sci/graphics/ports.h
+++ b/engines/sci/graphics/ports.h
@@ -83,6 +83,7 @@ public:
 
 	void offsetRect(Common::Rect &r);
 	void offsetLine(Common::Point &start, Common::Point &end);
+	void clipLine(Common::Point &start, Common::Point &end);
 
 	void priorityBandsInit(int16 bandCount, int16 top, int16 bottom);
 	void priorityBandsInit(byte *data);