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      Download the Game Design and Indie Game Marketing Freebook   07/19/17

      GameDev.net and CRC Press have teamed up to bring a free ebook of content curated from top titles published by CRC Press. The freebook, Practices of Game Design & Indie Game Marketing, includes chapters from The Art of Game Design: A Book of Lenses, A Practical Guide to Indie Game Marketing, and An Architectural Approach to Level Design. The GameDev.net FreeBook is relevant to game designers, developers, and those interested in learning more about the challenges in game development. We know game development can be a tough discipline and business, so we picked several chapters from CRC Press titles that we thought would be of interest to you, the GameDev.net audience, in your journey to design, develop, and market your next game. The free ebook is available through CRC Press by clicking here. The Curated Books The Art of Game Design: A Book of Lenses, Second Edition, by Jesse Schell Presents 100+ sets of questions, or different lenses, for viewing a game’s design, encompassing diverse fields such as psychology, architecture, music, film, software engineering, theme park design, mathematics, anthropology, and more. Written by one of the world's top game designers, this book describes the deepest and most fundamental principles of game design, demonstrating how tactics used in board, card, and athletic games also work in video games. It provides practical instruction on creating world-class games that will be played again and again. View it here. A Practical Guide to Indie Game Marketing, by Joel Dreskin Marketing is an essential but too frequently overlooked or minimized component of the release plan for indie games. A Practical Guide to Indie Game Marketing provides you with the tools needed to build visibility and sell your indie games. With special focus on those developers with small budgets and limited staff and resources, this book is packed with tangible recommendations and techniques that you can put to use immediately. As a seasoned professional of the indie game arena, author Joel Dreskin gives you insight into practical, real-world experiences of marketing numerous successful games and also provides stories of the failures. View it here. An Architectural Approach to Level Design This is one of the first books to integrate architectural and spatial design theory with the field of level design. The book presents architectural techniques and theories for level designers to use in their own work. It connects architecture and level design in different ways that address the practical elements of how designers construct space and the experiential elements of how and why humans interact with this space. Throughout the text, readers learn skills for spatial layout, evoking emotion through gamespaces, and creating better levels through architectural theory. View it here. Learn more and download the ebook by clicking here. Did you know? GameDev.net and CRC Press also recently teamed up to bring GDNet+ Members up to a 20% discount on all CRC Press books. Learn more about this and other benefits here.
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So I decided that I was tired of not working on the VM side of things, and rigged up a simple test harness for LLVM.

Basically, this creates the following situation:

  • getstuff() is a function defined in the native .EXE which returns a simple integer
  • answer() is a function defined in LLVM bitcode at runtime
  • answer() accepts one integer parameter, adds it to the return value of getstuff(), and returns the result
  • The native .EXE will JIT compile answer() to native code, execute it, and print its return value

    All this is pretty simple to do:

    int _tmain(int argc, _TCHAR* argv[])
    using namespace llvm;


    LLVMContext& Context = getGlobalContext();

    Module* module = new Module("EpochJIT", Context);

    IRBuilder<> Builder(Context);

    std::map NamedValues;

    std::vector args(1, Type::getInt32Ty(Context));
    FunctionType* functype = FunctionType::get(Type::getInt32Ty(Context), args, false);

    Function* func = Function::Create(functype, Function::ExternalLinkage, "answer", module);

    std::vector Args;

    unsigned Idx = 0;
    for(Function::arg_iterator AI = func->arg_begin(); Idx != Args.size(); ++AI, ++Idx)
    NamedValues[Args[Idx]] = AI;

    BasicBlock* block = BasicBlock::Create(Context, "entry", func);

    std::vector noargs;
    FunctionType* getstufffunctype = FunctionType::get(Type::getInt32Ty(Context), noargs, false);
    Function* getstufffunc = Function::Create(getstufffunctype, Function::ExternalLinkage, "getstuff", module);

    Value* stuff = Builder.CreateCall(getstufffunc);

    Value* addition = Builder.CreateAdd(NamedValues["a"], stuff, "addtmp");




    std::string ErrStr;
    ExecutionEngine* ee = EngineBuilder(module).setErrorStr(&ErrStr).create();
    std::cout << ErrStr << std::endl;
    return 1;

    void* fptr = ee->getPointerToFunction(func);
    int (*fp)(int) = (int (*)(int))fptr;

    std::wcout << fp(2) << std::endl;

    return 0;

    And the results speak for themselves:

    LLVM Test.png

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Ah, LLVM.. I've played with it a bit, such a quality library and if/when I get around to needing/wanting my own scripting language it is hands down my first choice for the backend.

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Yeah, I've been extremely impressed by the library so far. Very clean design and stupid powerful.

I honestly was pleasantly surprised to discover that it's possible to go from AST to JIT'ed native code in a lazy evening's worth of work.

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I was going to use it for a BASIC dialect I made a while back but I couldn't figure it out and the documentation wasn't of much help.
I might have to relook at it since you claim that it is so easy to use!

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Only problem I had at the time was the release didn't support VS2010 out of the box, but that's long since been fixed.

What I found helpful was following the tutorial series on making their toy language; it was a decent intro to the lib and gave you something to jump from into the docs.

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I wanted to mess with LLVM, but don't you have to install 4 GB of stuff just to get it up and running?

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Well, the compile of the LLVM project does take up a fair chunk of space when you factor in all the .obj files etc; the final library directory I think I was using was somewhere around 700meg, the 'build' directory does apprently take up 8gb however you do have to weight that against how good the library is and what it can do.

In short; while big that really isn't an issue.

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