i was bored so i did this using gradients Red Green Blue only and setting layers to additive.

Cool.
Might have a go at a few Gimp things now that I can.
Been busy with excel sheet data yesterday and today and now I am sick of it.

That does look cool.

Thanks guys,
not sure how cool it looks because i made it but it was definitely fun to play around with addition layers and only rgb. Now if only there's away to create a real color cube with all colors transparently shown like as if you can see through a cube and each point on the cube is associated with RGB based on XYZ i really am curious in how that cube might look

on the cube and even inside the cube as well since there are other colors hidden inside it.

i thought i would add a missing chunk to see grayish tones in the middle of cube.