Generate the plot. CAXIS= specifies a color for the axis lines and tick marks. ROTATE= specifies a rotation angle for the plot. SIZE= specifies the size of the plot symbols. XTICKNUM=, YTICKNUM=, and ZTICKNUM= specify the number of tick marks for the x, y, and z axes. ZMIN= and ZMAX= specify the minimum and maximum values for the z axis. 
proc g3d data=reflib.humid;
   scatter atemp*wtemp=relhum
         / shape='pillar'
           color=colorval
           caxis=blue
           rotate=-15
           size=.5
           yticknum=5
           xticknum=2
           zticknum=4
           zmin=0
           zmax=100;
run;
quit;