C++ / Angelscript interoperability

All containers can be created in C++ or angelscript. The angelscript side is more convenient.

C++ side quirks

• All containers are registered with angelscript as ref types
  • They must be created with new and deleted with container->refcount_Release()
• Tempspec'd containers use real C++ types and are actually nice to use unlike...
• Templated containers support all types and thus their interface is full of voidpointers.
  • Templated containers internally store each item in an aatc::common::primunion to avoid different allocation code
    • If the content is object or handle, primunion.ptr is a void* which points at the object
• AATC containers hold their native container in my_aatc_container.container
  • The native container should be used for iteration, the AATC container's functions should be used for everything else

Angelscript side quirks

• You must be careful when passing around containers to avoid accidental copies of entire containers
  • "Container@" will not copy
  • "Container &in" would copy, but doesn't even compile (because containers' opAssign and copy constructor are registered to take a handle)
  • "Container &out" will copy
  • "Container &inout" will not copy

Example of creating a vector<int> in C++ then passing it to angelscript:

//C++ side
//C++ side
//C++ side
#include "aatc_container_vector.hpp"


{
    aatc::container::tempspec::vector<int>* cont = new aatc::container::tempspec::vector<int>;

    for (int i = 0; i < 4; i++) {
        cont->push_back(i);
    }
    
    //Increment refcount here if you want C++ to have ownership of your container
    //cont->refcount_Add()

    asIScriptFunction* scriptfunc = my_module->GetFunctionByName("angelscript_function_who_wants_a_vector");
        context->Prepare(scriptfunc);
        context->SetArgAddress(0, cont);
    context->Execute();
    
    //The angelscript function will decrement the container's refcount after its done running and delete it unless you incremented the refcount above with cont->refcount_Add()
}

//Angelscript side
//Angelscript side
//Angelscript side

void angelscript_function_who_wants_a_vector(vector<int>@ cont){
    for(auto it = cont.begin();it++;){
        Print("value = " + it.value);
    }
}

//Prints
//Prints
//Prints
value = 0
value = 1
value = 2
value = 3

Example of creating a map<int,int> in C++ then passing it to angelscript:

//C++ side
//C++ side
//C++ side
#include "aatc_container_map.hpp"


{
    //typeinfo is required for templated containers
    asITypeInfo* tinfo = my_engine->GetTypeInfoByDecl("map<int,int>");
    
    aatc::container::mapped::templated::map* cont = new aatc::container::mapped::templated::map(tinfo);

    //Working with templated containers is a pain in C++, because everything wants a void*
    for (int i = 0; i < 4; i++) {
        int key = i;
        int value = 100 + i;
        cont->insert(&key, &value);
    }
    
    //Increment refcount here if you want C++ to have ownership of your container
    //cont->refcount_Add()

    asIScriptFunction* scriptfunc = my_module->GetFunctionByName("angelscript_function_who_wants_a_map");
        context->Prepare(scriptfunc);
        context->SetArgAddress(0, cont);
    context->Execute();
    
    //The angelscript function will decrement the container's refcount after its done running and delete it unless you incremented the refcount above with cont->refcount_Add()
}

//Angelscript side
//Angelscript side
//Angelscript side

void angelscript_function_who_wants_a_map(map<int,int>@ cont){
    for(auto it = cont.begin();it++;){
        Print("key = " + it.key + "   value = " + it.value);
    }
}

//Prints
//Prints
//Prints
key = 0   value = 100
key = 1   value = 101
key = 2   value = 102
key = 3   value = 103

Example of creating a vector<int> in angelscript then passing it to C++:

//C++ side
//C++ side
//C++ side
#include "aatc_container_vector.hpp"



void cpp_read_vector(aatc::container::tempspec::vector<int>* cont) {
    MySuperPrint("size = " + cont->size());
    
    //cont->container is the native std::vector<int> which the AATC container uses for storage
    for(int v : cont->container){
        MySuperPrint("value = " + v);
    }
}

{//Registration
    engine->RegisterGlobalFunction("void cpp_read_vector(vector<int>@)", asFUNCTION(cpp_read_vector), asCALL_CDECL);
}

//Angelscript side
//Angelscript side
//Angelscript side

void my_scriptmain(){
    vector<int> cont;
    
    for(int i=0; i<5;i++){
        cont.push_back(i);
    }
    
    cpp_read_vector(cont);
}

//Prints
//Prints
//Prints
size = 5
value = 0
value = 1
value = 2
value = 3
value = 4

Example of creating a map<int,int> in angelscript then passing it to C++ and iterating the map in C++:

//C++ side
//C++ side
//C++ side
#include "aatc_container_map.hpp"



void cpp_read_map(aatc::container::mapped::templated::map& cont) {
    /*
        Cont has its typeinfo set during construction in angelscript.
        
        We could examine it here with:
            cont->typeinfo_container
            cont->typeinfo_key
            cont->typeinfo_value
        
        But we already know that:
            cont->typeinfo_container == my_engine->GetTypeInfoByDecl("map<int,int>")
                cont->typeinfo_container->GetSubTypeId(0) == asTYPEID_INT32
                cont->typeinfo_container->GetSubTypeId(1) == asTYPEID_INT32
            
            cont->typeinfo_key == NULL
            cont->typeinfo_value == NULL
     */
    
    MySuperPrint("size = " + cont->size());
    
    //cont->container is the native std::map<primunion,primunion> which the AATC container uses for storage
    for(aatc::common::primunion_pair const& pup : cont.container){
        MySuperPrint("key = " + pup.first.i32 + "   value = " + pup.second.i32);
    }
}

{//Registration
    engine->RegisterGlobalFunction("void cpp_read_map(map<int,int> &inout)", asFUNCTION(cpp_read_map), asCALL_CDECL);
}

//Angelscript side
//Angelscript side
//Angelscript side

void my_scriptmain(){
    map<int,int> cont;
    
    for(int i=0; i<5;i++){
        cont.insert(i,100 + i);
    }
    
    cpp_read_map(cont);
}

//Prints
//Prints
//Prints
size = 5
key = 0   value = 100
key = 1   value = 101
key = 2   value = 102
key = 3   value = 103
key = 4   value = 104

Example of creating a map<string,string> in angelscript then passing it to C++ and iterating the map in C++:

//C++ side
//C++ side
//C++ side
#include "aatc_container_map.hpp"



void cpp_read_map(aatc::container::mapped::templated::map& cont) {
    /*
        Cont has its typeinfo set during construction in angelscript.
        
        We could examine it here with:
            cont->typeinfo_container
            cont->typeinfo_key
            cont->typeinfo_value
        
        But we already know that:
            cont->typeinfo_container == my_engine->GetTypeInfoByDecl("map<string,string>")
            cont->typeinfo_key == my_engine->GetTypeInfoByDecl("string")
            cont->typeinfo_value == my_engine->GetTypeInfoByDecl("string")
     */
    
    MySuperPrint("size = " + cont->size());
    
    //cont->container is the native std::map<primunion,primunion> which the AATC container uses for storage
    for(aatc::common::primunion_pair const& pup : cont.container){
        std::string* key = (std::string*)pup.first.ptr;
        std::string* value = (std::string*)pup.second.ptr;
        
        MySuperPrint("key = " + *key + "   value = " + *value);
    }
}

{//Registration
    engine->RegisterGlobalFunction("void cpp_read_map(map<string,string> &inout)", asFUNCTION(cpp_read_map), asCALL_CDECL);
}

//Angelscript side
//Angelscript side
//Angelscript side

void my_scriptmain(){
    map<string,string> cont;
    
    for(int i=0; i<5;i++){
        cont.insert("s" + i,"ss" + 100 + i);
    }
    
    cpp_read_map(cont);
}

//Prints
//Prints
//Prints
size = 5
key = s0   value = ss100
key = s1   value = ss101
key = s2   value = ss102
key = s3   value = ss103
key = s4   value = ss104