BCGControlBar Pro for MFC
void CBCGPRibbonGalleryCtrl::SetAutoInverseIconsInDarkTheme ( BOOL  bSet = TRUE)

Specifies whether the gallery's icons should be automatically inversed in the dark themes.

Parameters
bSetIf this parametr is TRUE, the icons will be automatically inverted in the dark themes.

Call this member function to specify whether the gallery's icons should be automatically inversed in the dark themes. This attribute is suitable for the icons specified using the SetImage() method with the resource ID only. It should be called before the image loads.