title: Plotting 3D surface from scatter points and a png on the same 3D graph
body: <p>I need to plot on the same graph a 3D surface based on a scatter points data and a 2D image (.png), positioned in a determined location on the graph to compare the data from both. So far I managed to do both separately (plotting the image and making the surface).</p>
  
  <p>However, when I try to bring both together on the same script, I get an error message ("Gridding of the color Column is not implemented") which occurs due to the command that creates the surface (dgrid3d) that conflicts with the image. I want to know how can I avoid this error.</p>
  
  <p>thanks in advance</p>
  
  <p>*EDIT</p>
  
  <p>The scatter points are on xyz format:</p>
  
  <pre><code>-100.000000 -25.000000 -4.122210
  
  -100.000000 -20.000000 -4.933388
  
  -100.000000 -15.000000 -7.902138
  
  -100.000000 -10.000000 -7.902138
  </code></pre>
  
  <p>and the image is a plain png.</p>
  
  <p>And the script I'm using is:</p>
  
  <pre><code>set hidden3d
  set samples 100
  set isosamples 100
  unset surface
  set pm3d
  set dgrid3d
  
   splot '444_0.dat' u 1:2:3 \
   splot 'test.png' \
   binary filetype=png flipy rotate=-90d center = (4,-25,5.7) perp=(0,1,0) with rgbimage
  </code></pre>
  
  <p>which doesnt work due to the error I pointed before</p>