README.md

RGB coloring

Original Demo

1

# # Demo of reading color information from the data file itself
# #
#
# #
# rgb(r,g,b) = int(r)*65536 + int(g)*256 + int(b)
#
# #
# set border 0
# unset xtics; unset ytics; unset ztics
# set rmargin 5; set lmargin 5; set bmargin 2
#
# set angle degrees
# xrgb(r,g,b) = (g-b)/255. * cos(30.)
# yrgb(r,g,b) = r/255. - (g+b)/255. * sin(30.)
# set arrow 1 from 0,0 to 0,1 nohead lw 3 lc rgb "red" back
# set arrow 2 from 0,0 to cos(-30), sin(-30) nohead lw 3 lc rgb "green" back
# set arrow 3 from 0,0 to cos(210), sin(210) nohead lw 3 lc rgb "blue" back
#
# set title "RGB color information read from data file"
# plot 'rgb_variable.dat' using (xrgb($1,$2,$3)):(yrgb($1,$2,$3)):(rgb($1,$2,$3)) \
#      with points pt 7 ps 4 lc rgb variable notitle

Numo.gnuplot do
  run "rgb(r,g,b) = int(r)*65536 + int(g)*256 + int(b)"
  set border:0
  unset :xtics; unset :ytics; unset :ztics
  set rmargin:5; set lmargin:5; set bmargin:2
  set angle:"degrees"
  run "xrgb(r,g,b) = (g-b)/255. * cos(30.)"
  run "yrgb(r,g,b) = r/255. - (g+b)/255. * sin(30.)"
  set :arrow, 1, from:[0,0], to:[0,1], nohead:true, lw:3, lc_rgb:"red", back:true
  set :arrow, 2, from:[0,0], to:"cos(-30), sin(-30)", nohead:true, lw:3, lc_rgb:"green", back:true
  set :arrow, 3, from:[0,0], to:"cos(210), sin(210)", nohead:true, lw:3, lc_rgb:"blue", back:true
  set title:"RGB color information read from data file"
  plot "'rgb_variable.dat'", using:'(xrgb($1,$2,$3)):(yrgb($1,$2,$3)):(rgb($1,$2,$3))', with:"points", pt:7, ps:4, lc_rgb:"variable", notitle:true
end

2

# set title "Both RGB color information\n and point size controlled by input"
# plot 'rgb_variable.dat' using (xrgb($1,$2,$3)):(yrgb($1,$2,$3)):(1.+2.*rand(0)):(rgb($1,$2,$3)) \
#      with points pt 7 ps var lc rgb variable notitle

Numo.gnuplot do
  set title:"Both RGB color information\n and point size controlled by input"
  plot "'rgb_variable.dat'", using:'(xrgb($1,$2,$3)):(yrgb($1,$2,$3)):(1.+2.*rand(0)):(rgb($1,$2,$3))', with:"points", pt:7, ps:"var", lc_rgb:"variable", notitle:true
end

3

# set border -1 front linetype -1 linewidth 1.000
# set ticslevel 0
# set xtics border
# set ytics border
# set ztics border
# #
# unset arrow 1
# unset arrow 2
# unset arrow 3
# #
# set xlabel "Red" tc rgb "red"
# set xrange [0:255]
# set ylabel "Green" tc rgb "green"
# set yrange [0:255]
# set zlabel "Blue" tc rgb "blue"
# set zrange [0:255]
#
# #
# splot 'rgb_variable.dat' using 1:2:3:(rgb($1,$2,$3)) with points pt 7 ps 4 lc rgb variable, \
#       '' using 1:2:3:(sprintf("0x%x",rgb($1,$2,$3))) with labels left offset 1 notitle

Numo.gnuplot do
  set border:-1, front:true, linetype:-1, linewidth:1.000
  set ticslevel:0
  set :xtics, :border
  set :ytics, :border
  set :ztics, :border
  unset :arrow, 1
  unset :arrow, 2
  unset :arrow, 3
  set xlabel:"Red", tc_rgb:"red"
  set xrange:0..255
  set ylabel:"Green", tc_rgb:"green"
  set yrange:0..255
  set zlabel:"Blue", tc_rgb:"blue"
  set zrange:0..255
  splot ["'rgb_variable.dat'", using:'1:2:3:(rgb($1,$2,$3))', with:"points", pt:7, ps:4, lc_rgb:"variable"],
    ["''", using:'1:2:3:(sprintf("0x%x",rgb($1,$2,$3)))', with:"labels", left:true, offset:1, notitle:true]
end

4

# # Unfortunately, not all platforms allow us to read hexadecimal constants
# # from a data file. Warn the user if that is the case.
# #
# if (0 == int('0x01')) \
#    set label 99 at screen .05, screen .15 "If you see only black dots,\nthis means your platform does not \nsupport reading hexadecimal constants\nfrom a data file. Get a newer libc."
#
# splot 'rgb_variable.dat' using 1:2:3:(5*rand(0)):4 with points pt 7 ps variable lc rgb variable \
#       title "variable pointsize and rgb color read as hexidecimal"

Numo.gnuplot do
  splot "'rgb_variable.dat'", using:'1:2:3:(5*rand(0)):4', with:"points", pt:7, ps:"variable", lc_rgb:"variable", title:"variable pointsize and rgb color read as hexidecimal"
end

5

# set label 99 ""
# #
# set border 0
# set xtics axis nomirror
# set ytics axis nomirror
# set ztics axis nomirror
# set xzeroaxis lt -1 lc rgb "red" lw 2
# set yzeroaxis lt -1 lc rgb "green" lw 2
# set zzeroaxis lt -1 lc rgb "blue" lw 2
# set xyplane at 0.0
#
# splot 'rgb_variable.dat' using 1:2:3:(5*rand(0)):(rgb($1,$2,$3)) with points pt 7 ps variable lc rgb variable \
#       title "variable pointsize and rgb color computed from coords"

Numo.gnuplot do
  set :label, 99, ""
  set border:0
  set :xtics, :axis, :nomirror
  set :ytics, :axis, :nomirror
  set :ztics, :axis, :nomirror
  set :xzeroaxis, lt:-1, lc_rgb:"red", lw:2
  set :yzeroaxis, lt:-1, lc_rgb:"green", lw:2
  set :zzeroaxis, lt:-1, lc_rgb:"blue", lw:2
  set :xyplane, at:0.0
  splot "'rgb_variable.dat'", using:'1:2:3:(5*rand(0)):(rgb($1,$2,$3))', with:"points", pt:7, ps:"variable", lc_rgb:"variable", title:"variable pointsize and rgb color computed from coords"
end

6

# set title "Demo of hidden3d with points only (no surface)"
# set hidden3d
# replot

Numo.gnuplot do
  set title:"Demo of hidden3d with points only (no surface)"
  set :hidden3d
  replot
end