Method SetReferenceKeyframe

src/database/Frame.cpp:278–301

}

void Frame::SetReferenceKeyframe(std::shared_ptr<Frame> reference_kf) {
    std::lock_guard<std::mutex> lock(m_pose_mutex);
    m_reference_keyframe = reference_kf;
    
    // Calculate relative transformation at the time of setting reference keyframe
    if (reference_kf) {
        // Current frame pose (direct from m_rotation, m_translation)
        Eigen::Matrix4f T_wb_current = Eigen::Matrix4f::Identity();
        T_wb_current.block<3, 3>(0, 0) = m_rotation;
        T_wb_current.block<3, 1>(0, 3) = m_translation;
        
        // Reference keyframe pose - need to unlock before calling GetTwb on another frame
        // to avoid potential issues, we get pose components directly
        Eigen::Matrix4f T_wb_ref = Eigen::Matrix4f::Identity();
        T_wb_ref.block<3, 3>(0, 0) = reference_kf->GetRotation();
        T_wb_ref.block<3, 1>(0, 3) = reference_kf->GetTranslation();
        
        // Calculate relative transformation: T_rel = T_ref^-1 * T_current
        m_T_relative_from_ref = T_wb_ref.inverse() * T_wb_current;
    } else {
        // No reference keyframe, set to identity
        m_T_relative_from_ref = Eigen::Matrix4f::Identity();
    }
}

std::shared_ptr<Frame> Frame::GetReferenceKeyframe() const {
    return m_reference_keyframe.lock();