set pm3d depthorder nohidden3d
set palette defined (0 "dark-green", 1 "white")
set parametric
set urange [0:2*pi]
set vrange [-pi:pi]
set samples 48
set isosamples 48,24
set view 75,15,1,1
set size 0.9,1
set style line 100 lw 0.2 lc rgb "navy"
unset key
set ticslevel 0
x1(u,v)=cos(u)+.5*cos(u)*cos(v)
y1(u,v)=sin(u)+.5*sin(u)*cos(v)
z1(u,v)=.5*sin(v)
x2(u,v)=1+cos(u)+.5*cos(u)*cos(v)
y2(u,v)=.5*sin(v)
z2(u,v)=sin(u)+.5*sin(u)*cos(v)

set term pngcairo crop 
set output "tori.png"
set multiplot layout 2,1
set size 1,1
set origin 0,0
splot x1(u,v), y1(u,v), z1(u,v) w pm3d,\
      x2(u,v), y2(u,v), z2(u,v) w pm3d 
set size 1,1
set origin 0,0
set hidden3d
unset tics
unset border
unset colorbox
splot x1(u,v), y1(u,v), z1(u,v) lw 0.5 lc rgb "navy",\
      x2(u,v), y2(u,v), z2(u,v) lw 0.5 lc rgb "dark-red"
unset multiplot

! convert -transparent white -geometry 50% tori.png tori_s.png