Step import color face rhivo7 vs rhino6

Dear rhino user ,

when I import a step file into rhino7 I get all color for each face and not into rhino 6 .

can you tell me where/how the color of the face is stored into 3dm file ?
because I would like to create a brep with different color on face but I need to know the method ?

thanks for your help

Rhino 7+ has per-face colors possible.

To remove them:
Select the object(s) and type _RemovePerFaceColors

To add them:
Sub-object (ctrl+shift+click) select the faces you want to color, then hit the color picker and select the color you want to apply.

Dear ,

ok I find the method associated to ON_BrepFace