Unity2MATLAB: Simple (although not-intuitive) conversion of coordinates and rotations from left-handed coordinate system (used by Unity) to right-handed (used by camera calibration toolbox in MATLAB\Octave)

L2R_coordinates.m

function coords = L2R_coordinates(Lcoords)

if size(Lcoords,1) > 0
    
    if size(Lcoords,2) > 1
        x = Lcoords(:,1);
        y = Lcoords(:,2);
        z = Lcoords(:,3);
    else
        x = Lcoords(1);
        y = Lcoords(2);
        z = Lcoords(3); 
    end
    
    coords = [x z y];
    
else 
    coords = [];
end

LE2R_rodrigues.m

function rvecs = LE2R_rodrigues(LE_angles)

rvecs = zeros(size(LE_angles));

for i = 1:size(LE_angles,1)
    
    if size(LE_angles,2) > 1
        aux = LE_angles(i,1);
        auy = LE_angles(i,2);
        auz = LE_angles(i,3);
    else
        aux = LE_angles(1);
        auy = LE_angles(2);
        auz = LE_angles(3);
    end
    
    ax = -aux;
    ay = -auz;
    az = -auy;
    
    RX = rotX(ax);
    RY = rotY(ay);
    RZ = rotZ(az);
    
    R = RZ*RX*RY;
    
    if size(LE_angles,2) > 1
        rvecs(i,:) = rodrigues(R);
    else
        rvecs = rodrigues(R);
    end
    
    
end

rotX.m

function U = rotX(a)
U = [ 1      0          0 
      0   cosd(a)  -sind(a);
      0   sind(a)   cosd(a); ];
end

rotY.m

function U = rotY(a)
U = [  cosd(a)  0   sind(a);
         0      1     0 
      -sind(a)  0   cosd(a); ];
end

rotZ.m

function U = rotZ(a)
U = [ cosd(a) -sind(a) 0;
      sind(a)  cosd(a) 0;
        0      0     1 ];
end