Starry Night MultiColor (Diamond Hotend)

I recently installed a 3 color diamond head/hotend to my 3d printer and wanted to make a image color print and thought Starry Night was a beautiful picture to use. I couldn't find a program to turn a color image into a 3d print so I made one. Yes, I'll admit I'm a mediocre programmer but am happy that I made something out of Perl to convert an image to its various colors in multiple ASCII STL files. I sort of wish I made it output binary stl instead but that was more work and for now it was good enough (maybe I'll do that in the future).

So I took a Vincent Van Gogh Starry Night image into Gimp and converted it to 12 colors 80x52 sized. I figured that I wanted each pixel (voxel) to be about 1mm cubed and I figured 80mm was plenty wide. Although it could be resized smaller and then made at higher resolution. I didn't want to go too crazy with the number of colors and 12 seemed to allow CMY (without black) to work mostly.

So the program I made takes in an image at whatever size and whatever colors and splits them into 2 stl files per color. This was because I was able to make the blocks wider but when I tried to merge them in the Y axis direction, things went weird. So instead I output every other line into two seperate files per color, then imported them to Tinkercad and merged them. I had trouble with the registration so I added a registration block - not sure if that will cause problems so I left the original files without the registration block and not merged also which can be imported into Repetier probably. I had to convert the files to binary STL anyway since Repetier couldn't import the ASCII STLs. (yeah I regret not outputting binary more now).

I tried loading it into Repetier and exporting and 3MF file but that didn't seem to work since when I tried to reimport it, it wasn't right. Oh well.

So anyway, I've included a text file with the colormap info. The rbg values are correct but I haven't verified the CMY values in the colormap file so you may want to spot check that if you try it. I haven't tried it yet because I don't have Cyan, Magenta, and Yellow filament yet and not sure when I'll get around to it. Of course, you'll need to adjust your color extruder weights in your 3d printer's firmware and probably slicer and maybe the host software and elsewhere (it's so easy!) for extruding the correct colors for each color so be aware of that if you aren't already.

I have included the ugly Perl program to convert an image to STL files (use at your own risk).
Usage: 3dimage.pl input_image_file output_pre_name colormap.txt
Example: 3dimage.pl starrynight.gif sn sncolormap.txt
For the image, you'll want to go into Gimp, and choose image->mode->indexed and pick a maximum number of colors or else you'll get too many colors to easily work with. 12 seemed about right for me. If you use the Perl program, please give me credit, and I'd love to see what you come up with so point me to a pic you happen to make. I use StrawberryPerl which is free on the Internet. You'll want to do "cpan install gd" also since it uses the gd module for getting the pixel info.

I thought about making a basrelief version where a second heightmap could be given to the program to make the image be 3dized instead of flat. I've included an image for an example of a program made long ago that did something like it.

If you try it and you get it printed, please show me your make! I'd love to see it actually printed (I'd wish more I was setup already to print it but I'd love to see it printed anyway).

The sn??.stl files are the 12 color stl files with registration guide.
The sn??_?.stl files are the 12 color stl files broken into every other line without a registration guide.
See the sncolormap.txt for color values.

This "thing" https://www.thingiverse.com/thing:3142654 was trying to make a lithopane (not a color print?) and was close to what i was wanting. His thing was sort of the inspiration for my thing.

But I'm mostly inspired by Jesus who saved and is saving this wretched person that I am.

I added a higher res version (0.5mm instead of 1mm cubes). Look for the high res zip file.
I added a black and white version of the high res also (maybe that's easier for dual-extruders?).

I don't have Cyan, Magenta, Yellow currently but I do have Black, White, and Blue. So with those colors and editing the image in Gimp, I converted it to print with those colors. I also scaled up the size x=1.6, Y=1.6, and Z=2.0 and gave it a raft to sit on.

Yay! I have a first print. I printed it with just black, white, and blue and need to adjust the colors more but hey, it worked for a first try! It sort of looks like a shag carpet!

https://www.youtube.com/watch?v=g5dXzrsnnq8