Display color pallette

Dear ROOTers,

I’m using ROOT to analyze a TTree and I want to make a 3d histogram with a fourth var
displayed with a color map.
I use the Draw function in this way:

ROOT> h222.Draw(“var1:var2:var3:var4”);

It’s possible to draw a “color axis” on the pad that display the color-content map of the fourth var ? (I’m thinking about something like 2d histo used with the draw option “COLZ”)
How can I do ?

Thanks !!!
Max

With 2d plots you can do:

h222.Draw(“var1:var2”,"",:COLZ");

but not with 3D histos there is not equivalent.