Each runway light is just a sphere mesh with one material applied to it. The materials in that code account for two colors of illumination that you see in the screenshot. The same material is applied to all the red lights, and the same materials is applied to all the green lights (they look blue).
Yes, "no_light" : true;
and... "color" : "x.x,x.x,x.x,0.99",
the last number must be less than 1.0. I've found that in some cases you want the 0.99 or 0.999, just below 1.0, and sometime 0.1 (very small value) is better. Also adjusting the reflect and roughness makes a difference.
It actually uses the opacity channel for illumination value, so you can add an "tex_opacity" map, white=illuminated, black=non-illuminated, and you can also do "alpha_masked" : true; for transparency mask from your opacity map.
Note: An illuminated material will glow at night, be be completely transparent during day time because it receives no illumination from the environment. I fix this by adding an opaque material to an additional material just behind the transparent illuminated one. It works perfect. You can even use an opacity map of the opaque material, as long as "no_light" : false; on the opaque material it should make it so that during day time you see through the transparent illuminated material and see the opaque one, and during night you see the illuminated one.
Hope that helps.
Regards,
Uriah
