Using Smalltalk as a scripting language
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Re: Using Smalltalk as a scripting language
 
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Re: Using Smalltalk as a scripting language
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>>> Most likely you'd have a cCall for #initialize >>> anyway. Having one for #new instead does not change much. >>> >> To my understanding ( from past smalltalk lectures at university where >> we worked with Squeak ) #new is responsible for allocating an object >> while #initialize or #init is responsible for setting up default values >> for the newly created instance. Therefore I proposed #new. Unless that >> is in GST this rule is slightly different. > > Yes, my reasoning is: if you used CObject, you would have needed > anyway a cCall to initialize the CObject. By not using CObject, you > just need your cCall to determine the correct size of the object so > you use #new. But it's not like one of the two is particularly more > hackish. their smalltalk type parameters. That sounds good. Let's see if I can get this one up and kicking. I can't remember of any game project using smalltalk for scripting. A pity, it's after all the mother of all OO languages :P ( and a cool language on top of it ). -- Yours sincerely Plüss Roland Leader and Head Programmer - Game: Epsylon ( http://epsylon.rptd.ch/ , http://www.moddb.com/games/4057/epsylon ) - Game Engine: Drag(en)gine ( http://dragengine.rptd.ch , http://www.moddb.com/engines/9/dragengine ) - Normal Map Generator: DENormGen ( http://epsylon.rptd.ch/denormgen.php ) _______________________________________________ help-smalltalk mailing list [hidden email] http://lists.gnu.org/mailman/listinfo/help-smalltalk |
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Re: Using Smalltalk as a scripting language
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Re: Using Smalltalk as a scripting language
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Re: Re: Using Smalltalk as a scripting language
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>>> So with other words no damage is done if I hijack #new for the creation >>> purpose and leaving #initialize to the scripts only for code to setup >>> their smalltalk type parameters. >> >> Yeah, you can even hijack #basicNew (normally a primitive, but a cCall >> is also a "primitive") and do the usual >> >> new [ ^super new initialize ] > > I had a 50% chance of getting it right, and didn't. I obviously meant > > new [ ^self basicNew initialize ] somehow to the class itself not the instance of it. But the class object is created by smalltalk so I can't mess with it. In fact I need to hack the class itself since using a cCall #new for an object I need to have access to the wrapped engine already. Maybe that's not clear. So let's make an example. class STSomething which wrapps CSomething. to create CSomething in c++ land I need a pointer to CEngine in c++ land. But when I assign a cCall for #new in STSomething I do not have access to the CEngine pointer. For this to work I need the STSomething class object to store the pointer to the CEngine so that once the cCall #new is called on STSomething I can create the new object with a brand new pointer to CSomething. So basically I need to mess with the STSomething object. Can I do the same hack you mentioned simply for STSomething like this? Object subclass: STSomething [ STSomething class [ <shape: #byte> new [ <cCall: 'CSomething_new' returning: #void args: #(#self)> ] ] ] Or is GST going to whip my ass for that? -- Yours sincerely Plüss Roland Leader and Head Programmer - Game: Epsylon ( http://epsylon.rptd.ch/ , http://www.moddb.com/games/4057/epsylon ) - Game Engine: Drag(en)gine ( http://dragengine.rptd.ch , http://www.moddb.com/engines/9/dragengine ) - Normal Map Generator: DENormGen ( http://epsylon.rptd.ch/denormgen.php ) _______________________________________________ help-smalltalk mailing list [hidden email] http://lists.gnu.org/mailman/listinfo/help-smalltalk |
Re: Re: Using Smalltalk as a scripting language
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Re: Re: Using Smalltalk as a scripting language
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>> Got stumped :( . I forgot that the class I try to wrap right now is a >> singleton. With other words in that case I need to assign a c-pointer >> somehow to the class itself not the instance of it. But the class object >> is created by smalltalk so I can't mess with it. > > No. Even if it is a singleton, *never* place singleton methods on the > class side. Add a #uniqueInstance class method cCall and use > gst_register_oop to ensure that the singleton instance is not garbage > collected. > >> So basically I need to mess with the STSomething object. Can I do the >> same hack you mentioned simply for STSomething like this? >> >> Object subclass: STSomething [ >> STSomething class [ >> <shape: #byte> >> new [<cCall: 'CSomething_new' returning: #void args: >> #(#self)> ] >> ] >> ] > > I answered above, but probably you want "returning: #smalltalk args: > #(#selfSmalltalk)" in general. Object subclass: DEEngine [ DEEngine class [ | uniqueInstance | uniqueInstance [ ^uniqueInstance ] ] quit [ <cCall: 'stClassEngine.ccQuit' returning: #void args: #(#self)> ] ] The idea I had is to assign the uniqueInstance instance variable of the class side from within the c code upon creation time. Doing so the uniqueInstance would work without having to cCall ( which is a problem since I would not have an engine pointer at that time ). I did hence the following: struct csEngineClass{ OBJ_HEADER; OOP uniqueInstance; }; // in the creation function OOP oopClass = gst_class_name_to_oop( "DEEngine" ); csEngineClass *csdata = ( csEngineClass* )OOP_TO_OBJ( oopClass ); csdata->uniqueInstance = pST->CreateNewObject( oopClass ); With CreateNewObject simply creating a new instance of the class. I can printf csdata->uniqueInstance and it has a proper OOP. When I do though "DEEngine uniqueInstance printNl" in my script I get nil. Something I didn't understand on the way you manipulate ST data from C? -- Yours sincerely Plüss Roland Leader and Head Programmer - Game: Epsylon ( http://epsylon.rptd.ch/ , http://www.moddb.com/games/4057/epsylon ) - Game Engine: Drag(en)gine ( http://dragengine.rptd.ch , http://www.moddb.com/engines/9/dragengine ) - Normal Map Generator: DENormGen ( http://epsylon.rptd.ch/denormgen.php ) _______________________________________________ help-smalltalk mailing list [hidden email] http://lists.gnu.org/mailman/listinfo/help-smalltalk |
Re: Re: Using Smalltalk as a scripting language
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Re: Re: Using Smalltalk as a scripting language
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>> Something I didn't understand on the way you manipulate ST data from C? > > You forgot the instance variables defined by superclasses of "DEEngine > class". Better initialize uniqueInstance lazily: > > DEEngine class [ > | uniqueInstance | > uniqueInstance [ ^uniqueInstance ifNil: [self new] ] > new [ <cCall: 'DEEngine.new' returning: #smalltalk args: #() ] > ] > > ... > > // in the creation function > OOP oopClass = gst_class_name_to_oop( "DEEngine" ); > deEngine::m_stUniqueInstance = pST->CreateNewObject( oopClass ); > gst_register_oop (deEngine::m_stUniqueInstance); > > ... > > static OOP deEngine::stNew () > { > return deEngine::m_stUniqueInstance; > } > > ... > > gst_define_cfunc ("DEEngine.new", deEngine::stNew); > > Nice to see some code in this thread! > Hence I am forced to work without any static class members there. The only chance I have to get this working is to somehow inject the created object into the class side variable. This would by itself work if the oop I assign would actually show up in smalltalk. I don't know yet why it stays nil. Did I obtain the wrong c pointer? Did I declare the class side variable incorrectly? -- Yours sincerely Plüss Roland Leader and Head Programmer - Game: Epsylon ( http://epsylon.rptd.ch/ , http://www.moddb.com/games/4057/epsylon ) - Game Engine: Drag(en)gine ( http://dragengine.rptd.ch , http://www.moddb.com/engines/9/dragengine ) - Normal Map Generator: DENormGen ( http://epsylon.rptd.ch/denormgen.php ) _______________________________________________ help-smalltalk mailing list [hidden email] http://lists.gnu.org/mailman/listinfo/help-smalltalk |
Re: Re: Using Smalltalk as a scripting language
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Re: Re: Using Smalltalk as a scripting language
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>> Nice try but this won't work. I have an engine pointer and therefore can >> not use a singleton in c++ ( although in smalltalk it becomes one ). >> Hence I am forced to work without any static class members there. The >> only chance I have to get this working is to somehow inject the created >> object into the class side variable. This would by itself work if the >> oop I assign would actually show up in smalltalk. I don't know yet why >> it stays nil. Did I obtain the wrong c pointer? Did I declare the class >> side variable incorrectly? > > No, you declared the Smalltalk struct incorrectly. > If you cannot use a static class member, use a global variable in the > module that implements the bindings. I just made it more clever than > it needed to be. static function nor a global variable. The entire engine does not use globals or singleton by itself. This is what makes it a bit tricky if a scripting language insists on not storing a user data pointer. So for example I can have multiple instances of the engine running but each engine instance has an own scripting environment and inside this scripting environment the smalltalk class is a singleton. Hence I have to attach the matching engine pointer to the matching smalltalk instance. Now I do not plan on using multiple instances but the design allows for this hence if possible I want to not break it. Maybe I need to do a hack then by having a class side object which just holds a pointer ( not the variable itself ). But then I have to provide a #uniqueInstance: which a stupid developer could break. Not the worst problem but to my understanding it should be possible to somehow inject an oop from c++ into smalltalk somehow ( well, except using a #selector: of course ). -- Yours sincerely Plüss Roland Leader and Head Programmer - Game: Epsylon ( http://epsylon.rptd.ch/ , http://www.moddb.com/games/4057/epsylon ) - Game Engine: Drag(en)gine ( http://dragengine.rptd.ch , http://www.moddb.com/engines/9/dragengine ) - Normal Map Generator: DENormGen ( http://epsylon.rptd.ch/denormgen.php ) _______________________________________________ help-smalltalk mailing list [hidden email] http://lists.gnu.org/mailman/listinfo/help-smalltalk |
Re: Re: Using Smalltalk as a scripting language
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Re: Re: Using Smalltalk as a scripting language
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>> Maybe I need to do a hack then by having a class side object which just >> holds a pointer ( not the variable itself ). > > No, why? > > Note that singletons can always be broken. #initialize can be broken > with #basicNew. In fact, everything in Smalltalk can be broken, since > there are no private methods. But I wouldn't worry about that. I just say "true becomes: false" :P > > Now that I understand more, anyway, I agree that the best thing to do > is what you were doing in the beginning---but with the class variable > names declared correctly based on the output of "Class allInstVarNames". How could I forget THAT. Of course I missed the previous instance variables. I'll change that right away. Sometimes I don't make enough RTFM :P it looks like. > If you have problems, you can also consider going on the > #gnu-smalltalk IRC channel on freenode.net. > Came from there to this mailing list as people said it's better here than there to ask. -- Yours sincerely Plüss Roland Leader and Head Programmer - Game: Epsylon ( http://epsylon.rptd.ch/ , http://www.moddb.com/games/4057/epsylon ) - Game Engine: Drag(en)gine ( http://dragengine.rptd.ch , http://www.moddb.com/engines/9/dragengine ) - Normal Map Generator: DENormGen ( http://epsylon.rptd.ch/denormgen.php ) _______________________________________________ help-smalltalk mailing list [hidden email] http://lists.gnu.org/mailman/listinfo/help-smalltalk |
Re: Re: Using Smalltalk as a scripting language
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Re: Re: Using Smalltalk as a scripting language
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In reply to this post by Paolo Bonzini-2
> You omitted all the variables that are part of every class. Try > "Class allInstVarNames". > Okay, I think I know what's the problem. I did the following. struct csEngineClass{ OBJ_HEADER; OOP uniqueInstance; }; According to the docs OBJ_HEADER adds all the fields from #Object. This would be then tough the instance variables of #Object. Is there a macro for the class side instance variables of Object? Or do I have to make them on my own ( not a problem by itself ). -- Yours sincerely Plüss Roland Leader and Head Programmer - Game: Epsylon ( http://epsylon.rptd.ch/ , http://www.moddb.com/games/4057/epsylon ) - Game Engine: Drag(en)gine ( http://dragengine.rptd.ch , http://www.moddb.com/engines/9/dragengine ) - Normal Map Generator: DENormGen ( http://epsylon.rptd.ch/denormgen.php ) _______________________________________________ help-smalltalk mailing list [hidden email] http://lists.gnu.org/mailman/listinfo/help-smalltalk |
Re: Re: Using Smalltalk as a scripting language
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Re: Re: Using Smalltalk as a scripting language
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> On 10/31/2009 04:22 PM, Roland Plüss wrote: >> Is there a macro >> for the class side instance variables of Object? Or do I have to make >> them on my own ( not a problem by itself ). >> > > The latter. Seems to have done the trick. I'm though not using anymore the macro approach. I'm a bit allergic against those :P . Looks now like this ( maybe you can add this somewhere to the docs for others if they wanna use it ). struct csObject{ OOP objSize; OOP objClass; }; struct csClassObject : public csObject{ OOP superclass; OOP subClasses; OOP methodDictionary; OOP instanceSpec; OOP instanceVariables; OOP name; OOP comment; OOP category; OOP environment; OOP classVariables; OOP sharedPools; OOP securityPolicy; OOP pragmaHandlers; }; Hence I used it now like this: struct csEngineClass : public csClassObject{ OOP uniqueInstance; }; struct csEngine : public csObject{ /* wrapped c++ data */ }; Now it works and I can inject the uniqueInstance from c++ land. -- Yours sincerely Plüss Roland Leader and Head Programmer - Game: Epsylon ( http://epsylon.rptd.ch/ , http://www.moddb.com/games/4057/epsylon ) - Game Engine: Drag(en)gine ( http://dragengine.rptd.ch , http://www.moddb.com/engines/9/dragengine ) - Normal Map Generator: DENormGen ( http://epsylon.rptd.ch/denormgen.php ) _______________________________________________ help-smalltalk mailing list [hidden email] http://lists.gnu.org/mailman/listinfo/help-smalltalk |
Re: Re: Using Smalltalk as a scripting language
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