TITANIC: star control, fmatrix refactoring

renamed fn2->MatRProd and fn3->MatLProd. They do post (R) and pre (L) multiplication.
scummvm · Aug 15, 2017 · 4bd4237 · 4bd4237
1 parent 970e4b2
commit 4bd4237
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Showing 3 changed files with 17 additions and 6 deletions.
diff --git a/engines/titanic/star_control/fmatrix.cpp b/engines/titanic/star_control/fmatrix.cpp
@@ -104,7 +104,7 @@ void FMatrix::set(const FVector &v) {
 	_row2.normalize();
 }
 
-void FMatrix::fn2(const FMatrix &m) {
+void FMatrix::matRProd(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;
@@ -120,7 +120,7 @@ void FMatrix::fn2(const FMatrix &m) {
 	_row3 = FVector(x3, y3, z3);
 }
 
-void FMatrix::fn3(const FMatrix &m) {
+void FMatrix::matLProd(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;

diff --git a/engines/titanic/star_control/fmatrix.h b/engines/titanic/star_control/fmatrix.h
@@ -85,8 +85,19 @@ class FMatrix {
 	 */
 	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.
+         * Matrix m is said to premultiply A (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 (previous this matrix).
+         */
+	void matLProd(const FMatrix &m);
 
 	/**
 	 * Returns true if the passed matrix equals this one

diff --git 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;
 }