Constant libnotcurses_sys::NCALPHA_BG_RGB_MASK

pub const NCALPHA_BG_RGB_MASK: u32 = crate::bindings::ffi::NC_BG_RGB_MASK; // 0x00ff_ffffu32

Extract these bits to get the background NcRgb value

See the detailed diagram at NcChannels

Note: This can also be used against a single NcChannel