Merge pull request #990 from dafioram/fmatrix_refactor

TITANIC: FMatrix refactoring

3 files changed, 66 insertions, 34 deletions

diff --git a/engines/titanic/star_control/fmatrix.cpp b/engines/titanic/star_control/fmatrix.cpp
index 23a2ce2203..724b5975d4 100644
--- a/engines/titanic/star_control/fmatrix.cpp
+++ b/engines/titanic/star_control/fmatrix.cpp
@@ -25,10 +25,31 @@
 
 namespace Titanic {
 
+//Non-member functions
+void matProd(const FMatrix &a, const FMatrix &m, FMatrix &C) {
+        C._row1._x = a._row1._y * m._row2._x + a._row1._z * m._row3._x + a._row1._x * m._row1._x;
+        C._row1._y = a._row1._x * m._row1._y + m._row2._y * a._row1._y + m._row3._y * a._row1._z;
+        C._row1._z = a._row1._x * m._row1._z + a._row1._y * m._row2._z + a._row1._z * m._row3._z;
+        C._row2._x = m._row1._x * a._row2._x + m._row3._x * a._row2._z + m._row2._x * a._row2._y;
+        C._row2._y = m._row3._y * a._row2._z + m._row1._y * a._row2._x + m._row2._y * a._row2._y;
+        C._row2._z = a._row2._z * m._row3._z + a._row2._x * m._row1._z + a._row2._y * m._row2._z;
+        C._row3._x = m._row1._x * a._row3._x + a._row3._z * m._row3._x + a._row3._y * m._row2._x;
+        C._row3._y = a._row3._y * m._row2._y + a._row3._z * m._row3._y + a._row3._x * m._row1._y;
+        C._row3._z = a._row3._x * m._row1._z + a._row3._y * m._row2._z + a._row3._z * m._row3._z;
+}
+
+//member functions
+
 FMatrix::FMatrix() :
 	_row1(1.0, 0.0, 0.0), _row2(0.0, 1.0, 0.0), _row3(0.0, 0.0, 1.0) {
 }
 
+FMatrix::FMatrix(const FVector &row1, const FVector &row2, const FVector &row3) {
+	_row1 = row1;
+	_row2 = row2;
+	_row3 = row3;
+}
+
 FMatrix::FMatrix(const DAffine &src) {
 	copyFrom(src);
 }
@@ -81,6 +102,13 @@ void FMatrix::identity() {
 	_row3 = FVector(0.0, 0.0, 1.0);
 }
 
+void FMatrix::set(const FMatrix &m) {
+	_row1 = m._row1;
+	_row2 = m._row2;
+	_row3 = m._row3;
+}
+
+
 void FMatrix::set(const FVector &row1, const FVector &row2, const FVector &row3) {
 	_row1 = row1;
 	_row2 = row2;
@@ -104,36 +132,18 @@ void FMatrix::set(const FVector &v) {
 	_row2.normalize();
 }
 
-void FMatrix::fn2(const FMatrix &m) {
-	float x1 = _row1._y * m._row2._x + _row1._z * m._row3._x + _row1._x * m._row1._x;
-	float y1 = _row1._x * m._row1._y + m._row2._y * _row1._y + m._row3._y * _row1._z;
-	float z1 = _row1._x * m._row1._z + _row1._y * m._row2._z + _row1._z * m._row3._z;
-	float x2 = m._row1._x * _row2._x + m._row3._x * _row2._z + m._row2._x * _row2._y;
-	float y2 = m._row3._y * _row2._z + m._row1._y * _row2._x + m._row2._y * _row2._y;
-	float z2 = _row2._z * m._row3._z + _row2._x * m._row1._z + _row2._y * m._row2._z;
-	float x3 = m._row1._x * _row3._x + _row3._z * m._row3._x + _row3._y * m._row2._x;
-	float y3 = _row3._y * m._row2._y + _row3._z * m._row3._y + _row3._x * m._row1._y;
-	float z3 = _row3._x * m._row1._z + _row3._y * m._row2._z + _row3._z * m._row3._z;
-
-	_row1 = FVector(x1, y1, z1);
-	_row2 = FVector(x2, y2, z2);
-	_row3 = FVector(x3, y3, z3);
-}
-
-void FMatrix::fn3(const FMatrix &m) {
-	float x1 = _row2._x * m._row1._y + m._row1._z * _row3._x + _row1._x * m._row1._x;
-	float y1 = m._row1._x * _row1._y + _row3._y * m._row1._z + _row2._y * m._row1._y;
-	float z1 = m._row1._x * _row1._z + m._row1._y * _row2._z + m._row1._z * _row3._z;
-	float x2 = _row1._x * m._row2._x + _row2._x * m._row2._y + _row3._x * m._row2._z;
-	float y2 = _row3._y * m._row2._z + _row1._y * m._row2._x + _row2._y * m._row2._y;
-	float z2 = m._row2._z * _row3._z + m._row2._x * _row1._z + m._row2._y * _row2._z;
-	float x3 = _row1._x * m._row3._x + m._row3._z * _row3._x + m._row3._y * _row2._x;
-	float y3 = m._row3._y * _row2._y + m._row3._z * _row3._y + m._row3._x * _row1._y;
-	float z3 = m._row3._x * _row1._z + m._row3._y * _row2._z + m._row3._z * _row3._z;
-
-	_row1 = FVector(x1, y1, z1);
-	_row2 = FVector(x2, y2, z2);
-	_row3 = FVector(x3, y3, z3);
+void FMatrix::matRProd(const FMatrix &m) {
+        FMatrix C = FMatrix();
+        FMatrix A = FMatrix(_row1,_row2,_row3);
+        matProd(A,m,C);
+        this->set(C);
+}
+
+void FMatrix::matLProd(const FMatrix &m) {
+        FMatrix C = FMatrix();
+        FMatrix A = FMatrix(_row1,_row2,_row3);
+        matProd(m,A,C);
+        this->set(C);
 }
 
 } // End of namespace Titanic
diff --git a/engines/titanic/star_control/fmatrix.h b/engines/titanic/star_control/fmatrix.h
index 95bb91cf73..f477500bad 100644
--- a/engines/titanic/star_control/fmatrix.h
+++ b/engines/titanic/star_control/fmatrix.h
@@ -47,6 +47,7 @@ public:
 	FVector _row3;
 public:
 	FMatrix();
+	FMatrix(const FVector &, const FVector &, const FVector &);
 	FMatrix(const DAffine &src);
 	FMatrix(const FMatrix &src);
 
@@ -73,6 +74,11 @@ public:
 	/**
 	 * Sets the data for the matrix
 	 */
+	void set(const FMatrix &m);
+
+	/**
+	 * Sets the data for the matrix
+	 */
 	void set(const FVector &row1, const FVector &row2, const FVector &row3);
 
 	/**
@@ -85,8 +91,17 @@ public:
 	 */
 	void set(const FVector &v);
 
-	void fn2(const FMatrix &m);
-	void fn3(const FMatrix &m);
+        /**
+         * Changes this matrix, A, to be C, where C=Am. Matrix m multiplies this matrix (A) on its Right.
+         * m is said to premultiply A (the previous this matrix).
+         */
+	void matRProd(const FMatrix &m);
+
+        /**
+         * Changes this matrix, A, to be C, where C=mA. Matrix m multiplies this matrix (A) on its Left.
+         * m is said to postmultiply A (the previous this matrix).
+         */
+	void matLProd(const FMatrix &m);
 
 	/**
 	 * Returns true if the passed matrix equals this one
@@ -112,6 +127,13 @@ public:
 	}
 };
 
+/**
+* Puts the matrix product between a and m in C, C = am
+* Called by MatLProd and MatLProd
+* Caller must preallocate output matrix
+*/
+void matProd(const FMatrix &a, const FMatrix &m, FMatrix &C);
+
 } // End of namespace Titanic
 
 #endif /* TITANIC_FMATRIX_H */
diff --git a/engines/titanic/star_control/viewport.cpp b/engines/titanic/star_control/viewport.cpp
index c3625b85c4..39d2c5f201 100644
--- a/engines/titanic/star_control/viewport.cpp
+++ b/engines/titanic/star_control/viewport.cpp
@@ -156,7 +156,7 @@ void CViewport::fn12() {
 	FPose s2(s1, m3);
 
 	m1.copyFrom(s2);
-	_orientation.fn2(m1);
+	_orientation.matRProd(m1);
 	_flag = false;
 }
 
@@ -181,7 +181,7 @@ void CViewport::reposition(double factor) {
 }
 
 void CViewport::fn15(const FMatrix &matrix) {
-	_orientation.fn3(matrix);
+	_orientation.matLProd(matrix);
 	_flag = false;
 }