%% C++ Object Methods as Legacy Functions
% This example shows you how to use the Legacy Code Tool to integrate legacy C++ 
% object methods.
%
% The Legacy Code Tool allows you to:
%
% * Provide the legacy function specification,
% * generate a C++ MEX S-function that is used during simulation to call the legacy code, and
% * Compile and build the generated S-function for simulation.
%

%   Copyright 1990-2020 The MathWorks, Inc.

%% Providing the Legacy Function Specification
% Functions provided with the Legacy Code Tool take a specific data
% structure or array of structures as the argument. The data structure is
% initialized by calling the function legacy_code() using 'initialize' as
% the first input. After initializing the structure, you have to assign its
% properties to values corresponding to the legacy code being integrated.
% The definition of the legacy C++ class being used in this example is:
%
%  class adder {
%    private:
%        int int_state;
%    public:
%        adder();
%        int add_one(int increment);
%        int get_val();
%  };
%
% The legacy source code is found in the files |adder_cpp.h| and
% |adder_cpp.cpp|.

% sldemo_sfun_adder_cpp
def = legacy_code('initialize');
def.SFunctionName = 'sldemo_sfun_adder_cpp';
def.StartFcnSpec  = 'createAdder()';
def.OutputFcnSpec = 'int32 y1 = adderOutput(int32 u1)';
def.TerminateFcnSpec = 'deleteAdder()';               
def.HeaderFiles   = {'adder_cpp.h'};
def.SourceFiles   = {'adder_cpp.cpp'};
def.IncPaths      = {'sldemo_lct_src'}; 
def.SrcPaths      = {'sldemo_lct_src'}; 
def.Options.language = 'C++';
def.Options.useTlcWithAccel = false;

%% Generating and Compiling an S-Function for Use During Simulation
% The function legacy_code() is called again with the first input set to
% 'generate_for_sim' in order to automatically generate and compile the
% C-MEX S-function according to the description provided by the input
% argument 'def'.  This S-function is used to call the legacy functions in
% simulation. The source code for the S-function is found in the file
% |sldemo_sfun_adder_cpp.cpp|.

legacy_code('generate_for_sim', def);

%% Generating an rtwmakecfg.m File for Code Generation
% After the TLC block file is created, the function
% legacy_code() can be called again with the first input set to 
% 'rtwmakecfg_generate' in order to generate an rtwmakecfg.m file to support
% code generation through Simulink(R) Coder(TM). Generate the rtwmakecfg.m 
% file if the required source and header files for the S-functions are not 
% in the same directory as the S-functions, and you want to add these 
% dependencies in the makefile produced during code generation.
%
% Note: Complete this step only if you are going to simulate the model in 
% accelerated mode.

legacy_code('rtwmakecfg_generate', def);

%% Generating a Masked S-Function Block for Calling the Generated S-Function
% After the C-MEX S-function source is compiled, the function 
% legacy_code() can be called again with the first input set to 'slblock_generate'
% in order to generate a masked S-function block that is configured to call that
% S-function.  The block is placed in a new model and can be copied to an
% existing model.

% legacy_code('slblock_generate', def);

%% Integration with Legacy Code
% The model |sldemo_lct_cpp sldemo_lct_cpp| shows integration with the
% legacy code.

open_system('sldemo_lct_cpp')
sim('sldemo_lct_cpp');
