#!/usr/local/bin/gnuplot -persist
# set terminal pngcairo  transparent enhanced font "arial,10" fontscale 1.0 size 600, 400 
# set output 'hidden_compare.1.png'
unset border
set dummy u, v
unset key
set parametric
set view 225, 206, 1.25, 0.5
set isosamples 200, 200
set hidden3d back offset 1 trianglepattern 3 undefined 1 altdiagonal bentover
set style data lines
unset xtics
unset ytics
unset ztics
set title "pm3d 2-color surface" 
set urange [ -3.14159 : 3.14159 ] noreverse nowriteback
set vrange [ 0.250000 : 3.14159 ] noreverse nowriteback
set xrange [ * : * ] noreverse writeback
set x2range [ * : * ] noreverse writeback
set yrange [ * : * ] noreverse writeback
set y2range [ * : * ] noreverse writeback
set zrange [ * : * ] noreverse writeback
set cbrange [ * : * ] noreverse writeback
set rrange [ * : * ] noreverse writeback
set pm3d depthorder 
set pm3d lighting primary 0.33 specular 0.2 spec2 0.3
set colorbox vertical origin screen 0.9, 0.2 size screen 0.05, 0.6 front  noinvert bdefault
unset colorbox
NO_ANIMATION = 1
splot (cos(u)+.5*cos(u)*cos(v))*(1.+sin(11.*u)/10.),       (sin(u)+.5*sin(u)*cos(v))*(1.+sin(11.*u)/10.),       0.5*sin(v) with pm3d fc ls 3