TryLoopOrNot.m

function needLoopTrial = TryLoopOrNot(map)

% First of all, we don't want to detect loop closure too frequently.
%(At least 10 keyscans away from last trial)
trialInterval = 1;
for k = length(map.keyscans)-1 : -1 : 1
    if ~map.keyscans(k).loopTried
        trialInterval = trialInterval + 1;
    else
        break;
    end
end
if trialInterval < 10
    needLoopTrial = false;
    return;
end

% Then we don't want to detect loop closure after a newly closed loop
% (At least 10 meters need to be traveled since last closure)
traveledDistance = 0;
for k  = length(map.keyscans)-1 : -1 : 1
    if ~map.keyscans(k).loopClosed
        dT = DiffPose(map.keyscans(k).pose, map.keyscans(k+1).pose);
        traveledDistance = traveledDistance + norm(dT(1:2));
        if traveledDistance > 10
            break;
        end
    else
        break;
    end
end
if traveledDistance < 10
    needLoopTrial = false;
    return;
end

% Now we see that a loop detection is wanted
needLoopTrial = true;