How to do 3D visualization of a multi-object volume, each object with different colors?

I have already visualize a volume, that only have one object, by the following commands:

v = smooth3(vv,'box',3);  % vv:volume
hpatch=patch(isosurface(v,0.5),'FaceColor',[1.0000 0.7109 0.7539],...
'EdgeColor','none',...
'AmbientStrength',.2,...
'SpecularStrength',.7,...
'DiffuseStrength',.4);
isonormals(v,hpatch)
%set(hpatch,'FaceColor',[0.2 1 0.7],'EdgeColor','none')
daspect([1,1,0.5])
view([-45,20])
axis tight
camlight right;
camlight left;
set(gcf,'Renderer','zbuffer'); lighting phong

Now I have a volume with 5 value (0:background,1:obj1, 2:obj2, 3:obj3, 4:obj4), I want to visualize each object with different colors in one view, for example:obj1 with yellow color, obj2 with green color and blah blah. How can I extend the code for multi-object 3D visualization?

Your help is appreciated