fix uninitialized alpha on update color algorithms

vcg/complex/algorithms/update/color.h

@@ -70,11 +70,11 @@ class UpdateColor
 	class ColorAvgInfo
 	{
 	public:
-		unsigned int r;
-		unsigned int g;
-		unsigned int b;
-		unsigned int a;
-		int cnt;
+		unsigned int r = 0;
+		unsigned int g = 0;
+		unsigned int b = 0;
+		unsigned int a = 0;
+		int cnt = 0;
 	};
 
 	/*! \brief This function colors all (or the selected) the vertices of a mesh.
@@ -139,7 +139,6 @@ class UpdateColor
 		RequirePerVertexColor(m);
 
 		ColorAvgInfo csi;
-		csi.r = csi.g = csi.b = csi.cnt = 0;
 		SimpleTempData<typename MeshType::VertContainer, ColorAvgInfo> TD(m.vert, csi);
 
 		ForEachTetra(m, [&] (TetraType & t) {
@@ -172,7 +171,6 @@ class UpdateColor
 		RequirePerVertexColor(m);
 
 		ColorAvgInfo csi;
-		csi.r=0; csi.g=0; csi.b=0; csi.cnt=0;
 		SimpleTempData<typename MeshType::VertContainer, ColorAvgInfo> TD(m.vert,csi);
 
 		FaceIterator fi;