Export to wavefront always gives white for ambient ka I'm using 2.76b on ubuntu. When I export to a wave front object, it will always set the material's ambiance (ka) as white. I've changed the World ambient color to multiple different colors, and it always exports as white.

Steps I use:


Create new blender file w/ default cube 
Click on World tab in properties. 
Expand World subsection 
Set Ambient to pink or something
File -> Export -> WaveFront


When I go to open up the .mtl file, it will still show as all 1's for the ka component for any material.
Okay, it appears that the export script just applies the ambient property in the shading sub section, which is a single value between 1 and zero that's just a multiplier for how much the global ambience the material receives.  It puts the single value as the component for each of the RGB values for ka upon export.