Implemented the SCI2.1 kMulDiv kernel function. Walking in Torin's Passage is done correctly now, without leaving trails

svn-id: r49909

3 files changed, 10 insertions, 0 deletions

diff --git a/engines/sci/engine/kernel.cpp b/engines/sci/engine/kernel.cpp
index d1b6ce72bc..3da34d44e4 100644
--- a/engines/sci/engine/kernel.cpp
+++ b/engines/sci/engine/kernel.cpp
@@ -387,6 +387,7 @@ SciKernelFunction kfunct_mappers[] = {
 	{ "List", kList, ".*" },
 	{ "Robot", kRobot, ".*" },
 	{ "IsOnMe", kIsOnMe, "iio.*" },
+	{ "MulDiv", kMulDiv, "iii" },
 
 #endif
 
diff --git a/engines/sci/engine/kernel.h b/engines/sci/engine/kernel.h
index 10225729d7..b3730cb6df 100644
--- a/engines/sci/engine/kernel.h
+++ b/engines/sci/engine/kernel.h
@@ -413,6 +413,7 @@ reg_t kIsHiRes(EngineState *s, int argc, reg_t *argv);
 reg_t kArray(EngineState *s, int argc, reg_t *argv);
 reg_t kListAt(EngineState *s, int argc, reg_t *argv);
 reg_t kString(EngineState *s, int argc, reg_t *argv);
+reg_t kMulDiv(EngineState *s, int argc, reg_t *argv);
 // "Screen items" in SCI32 are views
 reg_t kAddScreenItem(EngineState *s, int argc, reg_t *argv);
 reg_t kUpdateScreenItem(EngineState *s, int argc, reg_t *argv);
diff --git a/engines/sci/engine/kernel32.cpp b/engines/sci/engine/kernel32.cpp
index a077f110cf..d35dd38792 100644
--- a/engines/sci/engine/kernel32.cpp
+++ b/engines/sci/engine/kernel32.cpp
@@ -879,6 +879,14 @@ reg_t kCreateTextBitmap(EngineState *s, int argc, reg_t *argv) {
 	return NULL_REG;
 }
 
+reg_t kMulDiv(EngineState *s, int argc, reg_t *argv) {
+	int16 multiplicant = argv[0].toSint16();
+	int16 multiplier = argv[1].toSint16();
+	int16 denominator = argv[2].toSint16();
+
+	return make_reg(0, multiplicant * multiplier / denominator);
+}
+
 } // End of namespace Sci
 
 #endif	// ENABLE_SCI32