From: jglueck@... (=?ISO-8859-1?Q?Bernhard_Gl=FCck?=)
Date: 2001-09-23T11:42:17+09:00
Subject: [ruby-talk:21564] Returnin own C++ type from ruby method

Hi there again!

After having solved so many problems with ruby with the great help of
this newsgroup, i think I'll have another question for you all.

In my game engine there is a C++ Class called "Message" which is
exported to ruby... No problem it works quite well, I can instantiate
it and use it no problem at all...However now i have some "Messages"
that are not created by ruby but the C++ side of my program (incoming
from the network ) and I want to pass it to a ruby method ( since the
object is already exported with all methods it should work )

however what is the correct way to do this ?

My message export code looks like this:

/ -----------------------------------------------------------------------------
	static void MessageDelete( MessagePtr * inst )
	{
		delete inst;
	}
	
// -----------------------------------------------------------------------------
	static VALUE MessageNew( VALUE self )
	{
		MessagePtr * inst = new MessagePtr(); 
		*inst = MessageCreate( "Message" );
		VALUE t = Data_Wrap_Struct(self,0,SE_DELETE(MessageDelete),inst); 
		rb_obj_call_init(t, 0, NULL); 
		return t; 
	}

	void ScriptExporter::DefineMessage()
	{
		m_messageClass = rb_define_class_under(
GetModule(),"Msg",rb_cObject);
		rb_define_singleton_method(
m_messageClass,"new",SE_METHOD(MessageNew),0 );
		
		rb_define_method( m_messageClass,"Add",SE_METHOD(MessageAdd),1 );
		rb_define_method( m_messageClass,"Get",SE_METHOD(MessageGet),1 );
		rb_define_method( m_messageClass,"From",SE_METHOD(MessageFrom),0 );
		rb_define_method( m_messageClass,"Sent",SE_METHOD(MessageSendTime),0
);
		rb_define_method( m_messageClass,"Receive",SE_METHOD(MessageReceiveTime),0
);
		rb_define_method( m_messageClass,"To",SE_METHOD(MessageTo1),1 );
	}


Now how do i send a Message i get from the C++ side ( so it's already
constructed to a a method ? I would like to have it somehow like that:


VALUE MessageWrap( MessagePtr & ptr )
{
  // I have no clue how to implement this
}

void Message::SendToScript( VALUE object,MessagePtr & self )
{
	String callString = "On";
	callString += m_msg;
	
	// Generated for the method
	ID callId = rb_intern( callString.Get() );

	// Now create the parameter array for the call...
	Array<VALUE> args;

	// Wrap the message into a value
	args[0] = MessageWrap( self );			

	if ( rb_respond_to( object,callId ) )
	{
	        rb_funcall2( object,callId,args.Size(),args.Begin() );
	}
	else
	{
		LogWarning(("Object does not respond to message"));
	}

}



Bye the way in Ruby 1.6.4 the rb_class2name method seems to have a
bug.. It fails after 28 successive class with the same parameters,,
just to let you know...


Thanks in advance
Bernhard Gl�ck