Fix getRotation to handle matrices with scale

git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@2842 dfc29bdd-3216-0410-991c-e03cc46cb475

include/matrix4.h

@@ -848,34 +848,36 @@ namespace core
 	inline core::vector3d<T> CMatrix4<T>::getRotationDegrees() const
 	{
 		const CMatrix4<T> &mat = *this;
+		const core::vector3d<T> scale = getScale();
+		const core::vector3d<f64> invScale(core::reciprocal(scale.X),core::reciprocal(scale.Y),core::reciprocal(scale.Z));
 
-		f64 Y = -asin(mat(0,2));
+		f64 Y = -asin(mat[2]*invScale.X);
 		const f64 C = cos(Y);
 		Y *= RADTODEG64;
 
 		f64 rotx, roty, X, Z;
 
-		if (fabs(C)>ROUNDING_ERROR_f64)
+		if (!core::iszero(C))
 		{
-			const T invC = (T)(1.0/C);
-			rotx = mat(2,2) * invC;
-			roty = mat(1,2) * invC;
+			const f64 invC = core::reciprocal(C);
+			rotx = mat[10] * invC * invScale.Z;
+			roty = mat[6] * invC * invScale.Y;
 			X = atan2( roty, rotx ) * RADTODEG64;
-			rotx = mat(0,0) * invC;
-			roty = mat(0,1) * invC;
+			rotx = mat[0] * invC * invScale.X;
+			roty = mat[1] * invC * invScale.X;
 			Z = atan2( roty, rotx ) * RADTODEG64;
 		}
 		else
 		{
 			X = 0.0;
-			rotx = mat(1,1);
-			roty = -mat(1,0);
+			rotx = mat[5] * invScale.Y;
+			roty = -mat[4] * invScale.Y;
 			Z = atan2( roty, rotx ) * RADTODEG64;
 		}
 
 		// fix values that get below zero
 		// before it would set (!) values to 360
-		// that where above 360:
+		// that were above 360:
 		if (X < 0.0) X += 360.0;
 		if (Y < 0.0) Y += 360.0;
 		if (Z < 0.0) Z += 360.0;