Use \definecolor ... {gray} ... rather than ... {rgb} ... whenever possible

[zackw]

Whenever a color to be used is a shade of gray (r=g=b), tikzDevice should define it with the {gray} model rather than the {rgb} model.

[Sharpie]

When compiled by TeX, TikZ converts everything to the CMKY color space. Because of this, I'm not sure what we would gain for the price of increased complexity in the code.

[zackw]

When compiled by TeX, TikZ converts everything to the CMKY color space.

That's not what it's doing for me. \definecolor in the RGB space produces a b c RG/rg commands in the PDF, whereas the gray space produces x G/g.

[krlmlr]

Fixed in daqana#70.