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Simulink Graphical Figure Input

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Simulink Graphical Figure Input

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20 Jun 2003 (Updated )

Accepts mouse input from running Simulink simulation.

sfun_graphical_input(t,x,u,flag,Ts,axis_dims,x_label_str,y_label_str)
function [sys,x0,str,ts] = sfun_graphical_input(t,x,u,flag,Ts,axis_dims,x_label_str,y_label_str)
%SFUNTMPL General M-file S-function template
%   With M-file S-functions, you can define you own ordinary differential
%   equations (ODEs), discrete system equations, and/or just about
%   any type of algorithm to be used within a Simulink block diagram.
%
%   The general form of an M-File S-function syntax is:
%       [SYS,X0,STR,TS] = SFUNC(T,X,U,FLAG,P1,...,Pn)
%
%   What is returned by SFUNC at a given point in time, T, depends on the
%   value of the FLAG, the current state vector, X, and the current
%   input vector, U.
%
%   FLAG   RESULT             DESCRIPTION
%   -----  ------             --------------------------------------------
%   0      [SIZES,X0,STR,TS]  Initialization, return system sizes in SYS,
%                             initial state in X0, state ordering strings
%                             in STR, and sample times in TS.
%   1      DX                 Return continuous state derivatives in SYS.
%   2      DS                 Update discrete states SYS = X(n+1)
%   3      Y                  Return outputs in SYS.
%   4      TNEXT              Return next time hit for variable step sample
%                             time in SYS.
%   5                         Reserved for future (root finding).
%   9      []                 Termination, perform any cleanup SYS=[].
%
%
%   The state vectors, X and X0 consists of continuous states followed
%   by discrete states.
%
%   Optional parameters, P1,...,Pn can be provided to the S-function and
%   used during any FLAG operation.
%
%   When SFUNC is called with FLAG = 0, the following information
%   should be returned:
%
%      SYS(1) = Number of continuous states.
%      SYS(2) = Number of discrete states.
%      SYS(3) = Number of outputs.
%      SYS(4) = Number of inputs.
%               Any of the first four elements in SYS can be specified
%               as -1 indicating that they are dynamically sized. The
%               actual length for all other flags will be equal to the
%               length of the input, U.
%      SYS(5) = Reserved for root finding. Must be zero.
%      SYS(6) = Direct feedthrough flag (1=yes, 0=no). The s-function
%               has direct feedthrough if U is used during the FLAG=3
%               call. Setting this to 0 is akin to making a promise that
%               U will not be used during FLAG=3. If you break the promise
%               then unpredictable results will occur.
%      SYS(7) = Number of sample times. This is the number of rows in TS.
%
%
%      X0     = Initial state conditions or [] if no states.
%
%      STR    = State ordering strings which is generally specified as [].
%
%      TS     = An m-by-2 matrix containing the sample time
%               (period, offset) information. Where m = number of sample
%               times. The ordering of the sample times must be:
%
%               TS = [0      0,      : Continuous sample time.
%                     0      1,      : Continuous, but fixed in minor step
%                                      sample time.
%                     PERIOD OFFSET, : Discrete sample time where
%                                      PERIOD > 0 & OFFSET < PERIOD.
%                     -2     0];     : Variable step discrete sample time
%                                      where FLAG=4 is used to get time of
%                                      next hit.
%
%               There can be more than one sample time providing
%               they are ordered such that they are monotonically
%               increasing. Only the needed sample times should be
%               specified in TS. When specifying than one
%               sample time, you must check for sample hits explicitly by
%               seeing if
%                  abs(round((T-OFFSET)/PERIOD) - (T-OFFSET)/PERIOD)
%               is within a specified tolerance, generally 1e-8. This
%               tolerance is dependent upon your model's sampling times
%               and simulation time.
%
%               You can also specify that the sample time of the S-function
%               is inherited from the driving block. For functions which
%               change during minor steps, this is done by
%               specifying SYS(7) = 1 and TS = [-1 0]. For functions which
%               are held during minor steps, this is done by specifying
%               SYS(7) = 1 and TS = [-1 1].

% modified from sfuntmpl.m by
% Marc Compere
% CompereM@asme.org
% created : 17 June 2003
% modified: 20 June 2003

%   Copyright 1990-2002 The MathWorks, Inc.
%   $Revision: 1.18 $

%
% The following outlines the general structure of an S-function.
%
switch flag,

  %%%%%%%%%%%%%%%%%%
  % Initialization %
  %%%%%%%%%%%%%%%%%%
  case 0,
    [sys,x0,str,ts]=mdlInitializeSizes(Ts,axis_dims,x_label_str,y_label_str);

  %%%%%%%%%%%%%%%
  % Derivatives %
  %%%%%%%%%%%%%%%
  case 1,
    sys=mdlDerivatives(t,x,u);

  %%%%%%%%%%
  % Update %
  %%%%%%%%%%
  case 2,
    sys=mdlUpdate(t,x,u);

  %%%%%%%%%%%
  % Outputs %
  %%%%%%%%%%%
  case 3,
    sys=mdlOutputs(t,x,u);

  %%%%%%%%%%%%%%%%%%%%%%%
  % GetTimeOfNextVarHit %
  %%%%%%%%%%%%%%%%%%%%%%%
  case 4,
    sys=mdlGetTimeOfNextVarHit(t,x,u);

  %%%%%%%%%%%%%
  % Terminate %
  %%%%%%%%%%%%%
  case 9,
    sys=mdlTerminate(t,x,u);

  %%%%%%%%%%%%%%%%%%%%
  % Unexpected flags %
  %%%%%%%%%%%%%%%%%%%%
  otherwise
    error(['Unhandled flag = ',num2str(flag)]);

end

% end sfuntmpl

%
%=============================================================================
% mdlInitializeSizes
% Return the sizes, initial conditions, and sample times for the S-function.
%=============================================================================
%
function [sys,x0,str,ts]=mdlInitializeSizes(Ts,axis_dims,x_label_str,y_label_str)

%
% call simsizes for a sizes structure, fill it in and convert it to a
% sizes array.
%
% Note that in this example, the values are hard coded.  This is not a
% recommended practice as the characteristics of the block are typically
% defined by the S-function parameters.
%
sizes = simsizes;

sizes.NumContStates  = 0;
sizes.NumDiscStates  = 2;
sizes.NumOutputs     = 2;
sizes.NumInputs      = 0;
sizes.DirFeedthrough = 1;
sizes.NumSampleTimes = 1;   % at least one sample time is needed

sys = simsizes(sizes);

%
% initialize the initial conditions
%
x0  = [0,0]; % init with zero throttle, x(1)=0, and zero steering, x(2)=0

%
% str is always an empty matrix
%
str = [];

%
% initialize the array of sample times
%
ts = [Ts 0]; % set Ts to some stepsize to avoid evaluating this S-fcn every time step

% -----------------------------------------------------------------

%
% Initialize Figure Window
%
   handle.figure=findobj('type','figure','Tag','Throttle-Steering Figure');
   
   if isempty(handle.figure)
     handle.figure=figure('position',[100 100 400 300]); % rect = [left, bottom, width, height]
     %handle.figure=figure('position',[800 620 400 300]);
     %handle.figure=figure('position',[800 620 400 300],'WindowButtonDownFcn',@myCallback)
     %handle.figure=figure('position',[800 620 400 300],'WindowButtonMoveFcn',@myCallback_move,'WindowButtonDownFcn',@myCallback_clickdown)
   end

   % MDC set(h_anim,'name','Animation Figure', ...
   %        'renderer','z','resize','off', ...
   %        'position',[253 112 546 449],'clipping','off', ...
   %        'Tag','6DOF anim');
   set(handle.figure,'name','Throttle and Steering Input Window', ...
              'renderer','Painters', ...
              'Tag','Throttle-Steering Figure');
%Painters - fastest for simple graphics
%Zbuffer - better front-to-back sorting
%OpenGL - best & fastest for complicated 3D rendering

  if ~isempty(handle.figure) % if figure is there, delete current axes & start over
     h_del = findobj(handle.figure,'type','axes');
     delete(h_del);
     figure(handle.figure);
  end

%
% Initialize Axes & line object (the point)
%
%    steer_min = -pi; % (rad) max positive steering input signal
%    steer_max = +pi; % (rad) max negative steering input signal
%    throttle_min = -1.0; % (unitless) normalized max positive throttle signal
%    throttle_max = +1.0; % (unitless) normalized max negative throttle signal
%    axis_dims=[steer_min steer_max throttle_min throttle_max]; % [XMIN XMAX YMIN YMAX]

   handle.axes=axes;
   axis(axis_dims);

   line_color = [1 1 0];
   marker_color = 'b';
   line_coords = [ x0(1),x0(2),-1 ; x0(1),x0(2),+1];
   handle.point = line([x0(1),x0(1)],[x0(2),x0(2)],[-1 +1],'Color',line_color,'Marker','o','MarkerEdgeColor','b');

   set(handle.axes,'visible','on','box','off', ...
           'Color',[.8 .8 .8], ...
           'drawmode','fast', ...
           'XMinorTick','on',...
           'position',[0.15 0.15 0.7750 0.8150], ...
           'Tag','Throttle-Steering Axes', ...
           'YMinorTick','on');
   % axes position values: [left bottom width height] Default: [0.1300 0.1100 0.7750 0.8150]
   % axes 'box' can be 'on' or 'off' to optionally display the black world-frame box
   xlabel(x_label_str);
   ylabel(y_label_str);
   grid
   %set(handle.axes(1),'XMinorGrid','on')

   set(handle.figure,'userdata',handle)  % store handle structure in figure userdata space
   set(handle.axes,'userdata',axis_dims) % store axis dimensions in axes userdata space

% -----------------------------------------------------------------


% end mdlInitializeSizes

%
%=============================================================================
% mdlDerivatives
% Return the derivatives for the continuous states.
%=============================================================================
%
function sys=mdlDerivatives(t,x,u)

sys = [];

% end mdlDerivatives

%
%=============================================================================
% mdlUpdate
% Handle discrete state updates, sample time hits, and major time step
% requirements.
%=============================================================================
%
function sys=mdlUpdate(t,x,u)

   handle.figure = findobj('type','figure','Tag','Throttle-Steering Figure'); % retrieve figure handle
   handle = get(handle.figure,'userdata');

   axis_dims = get(handle.axes,'userdata'); % [XMIN XMAX YMIN YMAX]

   coords=get(handle.axes,'CurrentPoint'); % returns a 2x3 matrix in the form:
   % [ xback , yback , zback  ]
   % [ xfront, yfront, zfront ]

   % if new point is within the box, change to the new point,
   % otherwise, do not change current point to the new point
   % ...a little interval arithmetic by hand...
   if (coords(1,1)>=axis_dims(1) & coords(1,1)<=axis_dims(2)) % if x-dim passes the test...
      if (coords(1,2)>=axis_dims(3) & coords(1,2)<=axis_dims(4)) % and if y-dim passes the test...
         % then update the current marker point
         x(1) = coords(1,1); % set new x-dimension
         x(2) = coords(1,2); % set new y-dimension 
      end
   end

   % update the grahics object
   set(handle.point,'Xdata',[x(1) x(1)],'Ydata',[x(2) x(2)],'Zdata',[-1 +1]);

   % update the state
   sys = x;

% end mdlUpdate

%
%=============================================================================
% mdlOutputs
% Return the block outputs.
%=============================================================================
%
function sys=mdlOutputs(t,x,u)

   % output the current 2 states, the [x,y] graphics pair most recently updated
   sys = [x(1),x(2)]; % [x(1),x(2)] -> [abscissa, ordinate] -> [x,y]

% end mdlOutputs

%
%=============================================================================
% mdlGetTimeOfNextVarHit
% Return the time of the next hit for this block.  Note that the result is
% absolute time.  Note that this function is only used when you specify a
% variable discrete-time sample time [-2 0] in the sample time array in
% mdlInitializeSizes.
%=============================================================================
%
function sys=mdlGetTimeOfNextVarHit(t,x,u)

% unised unless ts=[-2 0] in mdlInitializesizes
sampleTime = Ts;    %  set the next hit to be Ts seconds later.
sys = t + sampleTime;

% end mdlGetTimeOfNextVarHit

%
%=============================================================================
% mdlTerminate
% Perform any end of simulation tasks.
%=============================================================================
%
function sys=mdlTerminate(t,x,u)

sys = [];

% end mdlTerminate








% % Callback for 'WindowButtonMoveFcn' in figure
% function myCallback_move(obj,eventdata)
% str=sprintf('\tWindowButtonMoveFcn callback executing');disp(str)
% end
% 
% % Callback for 'WindowButtonDownFcn' in figure
% function myCallback_clickdown(obj,eventdata)
% str=sprintf('\t\tWindowButtonDownFcn callback executing');disp(str)
% end



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