clear


%   INITIALIZE DDE CHANNEL


chan1 = DDEInit('OSLODDE', 'OSLO_Command');


%   OPEN LENS FILE IN OSLO


 chk = DDEExec (chan1, 'open len pri len gem_simple.len');
    if chk ~=1
        error('Cannot open lens file')
    end


%   DECENTER THE SECONDARY (3rd SURFACE) IN X DIRECTION


surface = '3';          % surface label
dir = 'x';              % direction of decenter


x_decenter = 0.1;       % amount of decenter
data = num2str(x_decenter);


message = ['dc' dir ' ' surface ' ' data];
chk = DDEExec (chan1,message);
    if chk ~=1
        error('Cannot execute OSLO command')
    end 


%   TILT THE SECONDARY (3rd SURFACE) ABOUT X AXIS


surface = '3';          % surface label
dir = 'a';              % axis of tilt


x_tilt = 0.2;           % amount of tilt
data = num2str(x_tilt);


message = ['tl' dir ' ' surface ' ' data];
chk = DDEExec (chan1,message);
    if chk ~=1
        error('Cannot execute OSLO command')
    end 


%   DO THE RAYTRACE


message = ['sbr'];              % spreadsheet buffer reset
chk = DDEExec (chan1,message);
    if chk ~=1
        error('Cannot reset the spreadsheet in OSLO')
    end
    
message = ['trr'];              % trace reference ray
chk = DDEExec (chan1,message);
    if chk ~=1
        error('Cannot trace reference ray in OSLO')
    end     
    
%   RETRIVE THE RAY INTERCEPT IN THE PUPIL
 
message = '+ssb(3,1)';        % y coordinate of intercept
y_intercept = DDEReq(chan1, message);


message = '+ssb(3,2)';        % x coordinate of intercept
x_intercept = DDEReq(chan1, message);


%   CLOSE DDE CHANNEL
    
DDETerm (chan1);