Starry Night program to create image gcode

This is mostly just show and tell of an experiment...

So I have a buddy Tim McGough that suggested I should try to make the Starry Night Van Gogh image by outputting colored dots by swiping from left to right. This is different than my previous method of outputting STL files for each color. Instead, this would require custom gcode for the printer.

I started by using only black and white (although more colors would work too) and making a program that would output gcode to make 1mm x 0.4 (nozzle width) of filament for each pixel doing that for 2 or 3 lines for each row. Well that was an ugly smeary mess and nothing was discernible other than I could tell it was switching colors only that it was so mixed that it was just mud. So basically, the diamond head needs more time to switch colors when mixing. Think of this as one mm line dot per one pixel. (see ugly pic on print bed)

I then tried for each pixel, going up 0.4, then right 0.4, down 0.4, then right 0.4. So that's 1