4 files changed, 24 insertions, 13 deletions
diff --git a/engines/titanic/star_control/daffine.cpp b/engines/titanic/star_control/daffine.cpp
index a7bed770c7..56c705b6a5 100644
--- a/engines/titanic/star_control/daffine.cpp
+++ b/engines/titanic/star_control/daffine.cpp
@@ -29,7 +29,7 @@ namespace Titanic {
 DAffine *DAffine::_static;
 
 DAffine::DAffine() :
-	_col1(0.0, 0.0, 0.0), _col2(0.0, 0.0, 0.0), _col3(0.0, 0.0, 0.0) {
+	_col1(0.0, 0.0, 0.0), _col2(0.0, 0.0, 0.0), _col3(0.0, 0.0, 0.0), _col4(0.0, 0.0, 0.0) {
 }
 
 DAffine::DAffine(int mode, const DVector &src) {
@@ -55,8 +55,8 @@ DAffine::DAffine(int mode, const DVector &src) {
 	}
 }
 
-DAffine::DAffine(Axis axis, double amount) {
-	setRotationMatrix(axis, amount);
+DAffine::DAffine(Axis axis, double angleDeg) {
+	setRotationMatrix(axis, angleDeg);
 }
 
 DAffine::DAffine(const FMatrix &src) {
@@ -74,10 +74,9 @@ void DAffine::deinit() {
 	_static = nullptr;
 }
 
-void DAffine::setRotationMatrix(Axis axis, double amount) {
-	const double FACTOR = 0.0174532925199433;
-	double sinVal = sin(amount * FACTOR);
-	double cosVal = cos(amount * FACTOR);
+void DAffine::setRotationMatrix(Axis axis, double angleDeg) {
+	double sinVal = sin(angleDeg * Deg2Rad);
+	double cosVal = cos(angleDeg * Deg2Rad);
 
 	switch (axis) {
 	case X_AXIS:
diff --git a/engines/titanic/star_control/daffine.h b/engines/titanic/star_control/daffine.h
index 50f8b9580b..50450b9427 100644
--- a/engines/titanic/star_control/daffine.h
+++ b/engines/titanic/star_control/daffine.h
@@ -51,18 +51,30 @@ public:
 public:
 	DAffine();
 	DAffine(int mode, const DVector &src);
-	DAffine(Axis axis, double amount);
+	DAffine(Axis axis, double angleDeg);
 	DAffine(const FMatrix &src);
 
 	/**
-	 * Sets up a matrix for rotating on a given axis by a given amount
+	 * Sets up an affine matrix for rotating on a given axis by an amount in degrees
 	 */
-	void setRotationMatrix(Axis axis, double amount);
+	void setRotationMatrix(Axis axis, double angleDeg);
 
+	/**
+	 * Return the Inverse of this Daffine
+	 */
 	DAffine inverseTransform() const;
 
+	/**
+	 * Change this Daffine to have its first three columns be the src matrix
+         * and the 4rth column to be (three) zeros
+	 */
 	void loadTransform(const CMatrixTransform &src);
 
+	/**
+	 * Do the affine product between this Daffine on the left
+         * and the m Daffine matrix on the right. This is product is NOT the same
+         * as multiplying two matrices of dimensions 4x4.
+	 */
 	DAffine compose(const DAffine &m);
 };
 
diff --git a/engines/titanic/star_control/dvector.cpp b/engines/titanic/star_control/dvector.cpp
index 1f873b5764..9f35ff6b67 100644
--- a/engines/titanic/star_control/dvector.cpp
+++ b/engines/titanic/star_control/dvector.cpp
@@ -26,9 +26,6 @@
 
 namespace Titanic {
 
-const double Rad2Deg = 180.0 / M_PI;
-const double Deg2Rad = 1.0 / Rad2Deg;
-
 double DVector::normalize() {
 	double hyp = sqrt(_x * _x + _y * _y + _z * _z);
 	assert(hyp);
diff --git a/engines/titanic/star_control/dvector.h b/engines/titanic/star_control/dvector.h
index eda69f9b81..bff271dd6f 100644
--- a/engines/titanic/star_control/dvector.h
+++ b/engines/titanic/star_control/dvector.h
@@ -27,6 +27,9 @@
 
 namespace Titanic {
 
+const double Rad2Deg = 180.0 / M_PI;
+const double Deg2Rad = 1.0 / Rad2Deg;
+
 class DAffine;
 
 /**