Added default values in the constructors of Vec2,Vec3,Vec4 and Quat

default constructors.

include/osg/Quat

@@ -29,7 +29,7 @@ class SG_EXPORT Quat
 	---------------------------------------------------------- */
 	Vec4 _fv;	// a four-vector
 
-	Quat() {}
+	Quat(): _fv(0.0f,0.0f,0.0f,1.0f) {}
 	Quat( float x, float y, float z, float w ):  _fv(x,y,z,w) {}
 	Quat( const Vec4& v ): _fv(v) {}
 

include/osg/Vec2

@@ -22,7 +22,7 @@ class Vec2
 {
     public:
 
-        Vec2() {} // no operations done to maintain speed
+        Vec2() {_v[0]=0.0f; _v[1]=0.0f;}
         Vec2(float x,float y) { _v[0]=x; _v[1]=y; }
 
         float _v[2];

include/osg/Vec3

@@ -21,7 +21,7 @@ class Vec3
 {
     public:
 
-        Vec3() {} // no operations done to maintain speed
+        Vec3() { _v[0]=0.0f; _v[1]=0.0f; _v[2]=0.0f;}
         Vec3(float x,float y,float z) { _v[0]=x; _v[1]=y; _v[2]=z; }
 
         float _v[3];

include/osg/Vec4

@@ -23,7 +23,7 @@ class Vec4
 
 	// Methods are defined here so that they are implicitly inlined
 
-        Vec4() {} // no operations done to maintain speed
+        Vec4() { _v[0]=0.0f; _v[1]=0.0f; _v[2]=0.0f; _v[3]=0.0f;}
         Vec4(float x, float y, float z, float w)
         {
             _v[0]=x; _v[1]=y; _v[2]=z; _v[3]=w;