First of all I read the offcial comparison OpenSG and OpenSceneGraph. My current goal is to create a small game engine for learning purpose. I started with pure OpenGL but then I found those scene graph libraries which are looking quite nice.
I would like to know the differences between those two scene graphs. Their comparison was very vague. For example OSG stated that OpenSG is probably better in multithreading.
OpenSG stated and I quote
OpenScenegraph leaned heavily on the Performer side of things in the
beginning .... OpenSG leaned more on the Fahrenheit side... These
days, in your self-interest, you should be using an Open Source system
like OpenSG.
I would like to know the difference between OpenSG and OpenSceneGraph.
It is hard to define, for those not versed in SceneGraph lore.
OpenSG has some more clever multithreading features that OpenSceneGraph lacks. However, OpenSceneGraph seems to make up for it with a much larger and more vibrant community, and more extensive derivative and add-on tools.
I chose OpenSceneGraph myself nearly ten years ago and have not regretted the decision.
You might also consider more high-level game tools like OGRE, which might be more in line with what you want than either OpenSG or OSG.
Related
I've been playing around with "Gloss" for a day now but I feel like my possibilities are very limited.
Can you recommend a more powerful library?
If there is a simple 3D library, I'd like to use it but if it gets significantly more complex then I'm also fine with staying at 2D for the moment. I can't exactly tell you what I expect from the new library but it should be more flexible and provide more (advanced) features.
PS: I'm on Windows 7 64bit if that matters
I think the question may be a little vague and "more powerful" is certainly subjective. But since you mentioned that you were on Windows 7-x64 then I can only guess to point you towards HGamer3D as a possible solution. I've heard some good things about it, but I've never used it myself. In any case there looks to be plenty to chew on there.
OpenGL.
An introductory tutorial, by Mikael Vejdemo Johansson,
loosely based on the tutorial by Sven Eric Panitz.
Does anyone have experience working with language workbench tools such as Xtext, Spoofax, and JetBrains' MPS? I'm looking to try one out and am having a hard time finding a good comparison of the different tools. What are the pros and cons of each?
I'm looking to build DSLs that generate python code, so I'm especially interested to hear from people who've used one of these tools with python (all three seem pretty Java-focused... why is that?). The DLSs are primarily for my own use, so I care less about building a really pretty IDE than I do about it being KISS to define the syntax and write the code generator. The ability to type-check / do static analysis of the DLSs would be pretty cool too.
I'm a little afraid of getting far down a path, hitting a wall, and realizing that all my code is in a format that can't be ported to anything else -- is that a risk with these tools? MPS in particular seems a little scary since as I understand it you don't really generate text-based syntaxes but rather build specialized editors for ASTs.
Markus Voelter does a pretty good job comparing those three in se-radio and Software ArchitekTOUR podcasts.
The basic idea is, that Xtext is most used, therefore most stable and documented, and it is based on popular Eclipse platform and modeling ecosystem - EMF which surrounds it. On the other hand it is parser based and uses ANTLR internally, which means the kind of grammars you can define is limited and languages cannot be combined easily.
Spoofax is an academic product with least adoption of those three. It is also parser based, but uses its own parser generator internally which allows language combinations.
Jetbrains MPS is projection based, which gives much freedom to language designer and allows combinations of languages. *t also has solid support. Drawback might be the learning curve.
None of these tools is strictly Java focused as target language for code generators. Xtext uses Xpand templates, which are plain text. I don't really know how code generation in Spoofax works. MPS has its base language, which is said to be subset of Java, but there are different alternatives.
I personally use Xtext because of its simplicity and maturity, but those strong limitations given by its design make it not a very future proof choice.
I have chosen XText in the same case two weeks ago, but I don't know anything about Spoofax.
My first impression - Xtext is very simple and productive.
I have made my first realife(but very simple) project in 30 minutes, I have generated a graphviz dot graph and html report.
I don't like MPS because I prefer plain text source and destination files.
There are other systems for doing this kind of thing. If your goal is building tools, you don't necessarily have to look to an IDE with an integrated tool; sometimes you can find better tools that have focused on utility rather than IDE integration
Consider any of the pure program transformation tools:
TXL (practical, single paradigm)
Stratego (Spoofax before it was transplanted into Eclipse)
Rascal (research, very nicely designed in many ways)
DMS Software Reengineering Toolkit (happens to be mine; commercial; used to do heavy duty DSL/conventional langauge analysis and transformation including on C++)
These all provide good mechanisms for defining DSLs and transforming them.
What really matters is the support machinery for carrying out "life after parsing".
I 've experimented for a couple of days with Xtext and while the tool looks promising I was eventually put off by the tight integration with the Eclipse ecosystem and the pain one has to go through just to solve what should be given hassle-free out of the box: a headless run of the code generator you implemented. See here for some of the minutiae one has to go through (and it's not even properly documented on the Xtext web site but rather on a blog, meaning its an ad-hoc patch that could very well break on the next release).
Will take another look in half a year to see if there has been any improvement on this front.
Take a look at the Markus Völter's book. It does a very comprehensive comparison of these 3 technologies.
http://dslbook.org
XText is very well maintained but this doesn't mean it's problem-less. Getting type-system, scoping and generation running isn't as easy as advertised.
Spoofax is scannerless, (simplifying grammar composition). Not that well documented, but seems complete.
MPS is projectional. A pro for language composition and con for editing. Supports multiple editors for an AST and will soon even support a nice diagram editor. Base language documentation isn't that good. Typesystem, scoping, checking is very well handled. Model to model transformations are done by the solver. My colleagues using it complain about model to text languages. (My opinion M2M wasn't that intuitive either.)
Years ago Microsoft had the OSLO project. MGrammar and especially Quadrant were very promising. It was possible to represent your model in table, form, text or diagram view. But suddenly they've cancelled the project (and perhaps shot the people working on it)
Perhaps today the best place to compare different language workbenches is http://www.languageworkbenches.net/ and there http://www.languageworkbenches.net/past-editions/ shows how a set of Language Workbenches implement a similar kind of task: a dsl for a particular domain.
Update 2022: as links were broken and newer articles on the topic are written see the site referred above at:
https://web.archive.org/web/20160324201529/http://www.languageworkbenches.net/
References to article reviewing language workbenches include: 1) State of the art: https://link.springer.com/chapter/10.1007/978-3-319-02654-1_11 and 2) Empirical evaluation: https://hal.archives-ouvertes.fr/file/index/docid/706841/filename/Evaluation_of_Modeling_Tools_Adaptation.pdf
I am from .net C# background and I want to learn DirectX. I have knowledge of C++ but I am fairly new to graphic world.
I am little confused about how to start learning directx, should I start learning direct directly or buy a basic graphic book like hern and baker and then jump to directx.
Which is the recommended book for learning basic graphic concepts, is it hern and baker? Is there any directx book which will cover graphic concepts as well?
I think that keeping a basic graphics book is allways good, because i can use it as reference anytime
Any suggestions from experts here?
You say that you have a C# background so I am going to assume you are more comfortable with C# then C++. Also, you say that you have knowledge of C++ so I will assume that you already have an understanding of memory management.
If you just want to learn and become more comfortable with the graphics pipeline you should check out SlimDX and XNA. They both allow you to use DirectX without having to dive into C/C++.
As for whether to learn the theory or API first I don't think you should do either one first. It makes sense to learn them asynchronously. Pick up a book on the theory but mess around with an API at the same time.
I highly recommend XNA. People commonly say that you should stick with C++ if you want to develop games but I strongly disagree. XNA will allow you to learn more high level game concepts in less time than if you use C++ and DirectX alone. You will be able to focus on learning why you are doing something rather than how to manage the memory. If in the future you decide that game development is a serious passion then by all means C++ is the way to go. You will find that XNA's graphics pipeline closely mirrors DirectX 9 and wont have much trouble moving to C++.
Also, DirectX 9 should be good enough for any beginner and it will give you a better understanding of how and why things have changed in 10 and 11. However, if you really want bleeding edge technologies you can try out SlimDX which is a C# wrapper for DirectX.
With all this said, XNA offers many easy to understand samples that you can start playing with on their educational catalog page. Also, check out ziggyware (great collection of xna tutorials).
Also, there are many blogs you can check out. A lot of them have excellent tutorials on them. Here are some off the top of my head:
Reimer Grootjans
Shawn Hargreaves
Richard Dodsworth
Renaud Bédard
Nick Gravelyn
Finally, here are 2 graphics books that I highly recommend (they are pretty complex and will last you a long time):
Fundamentals of Computer
Graphics
Real-Time Rendering
They are not directly related to DirectX, but rather they cover the theory every graphics developer should know. (from linear algebra to texture mapping to volumetrix rendering...)
Well I have to disagree with the C# option. If you don't have a deadline to finish the game, then I recommend using the language that teach you most. Working with 3d graphics is A LOT about management so if you are avoding it you are not actually learning but just using it, ie. you not only have to manage memory but the actual render calls you make and the device state changes, a lot of things that you will never know by avoding lower level, and which applies for other APIs too such as OpenGL or for other kind of devices. I think the best way of knowing how the api works is by using the api, instead of a bunch of helper libraries. You can use the helper libraries when you really need it instead (which you can find in their C++ version anyway).
In the DX SDK you can also find the Sample Browser with some sample applications with their documentation and you have the DirectX Utility Toolkit which contains a framework and libraries to make a DirectX app without having to worry much about the nasty device things such as enumeration and config. It also comes with a GUI system and a settings dialog for the device config. I doubt you can find those in C# and they are very good if you want to start with DX.
Some resources that helped me when I started were
the zophusX tutorials
and a book called "Introduction to 3D Game Programming with DirectX 9.0c", by Frank D. Luna (there is the DX10 version now)
and probably the book 3d Game Engine Programming by Stephan Zerbst also helped me to understand some things about how to work better with the apis. Though you may have to buy them in order to read them. They are helpful to start with both some theory and using the API at the same time.
I think if your target is to learn how to make a game then you can use any language/library you want you don't even need to know a programming language :) but if your target is learning DirectX and graphics APIs you should definitively start with the C++ api which is the "actual" DX.
If you have a bit of extra money, I was very impressed with the DirectX graphics courses from http://www.gameinstitute.com. The textbook they provide was very good as far as the other DirectX books I've seen are concerned. The first module DirectX Graphics I starts off with a bit of a math review and some 3D fundamentals before diving into setting up and using DirectX. By the end of the first module you will have built a textured terrain renderer and an indoor scene.
Overall the courses are not that expensive when you consider how much books on the subject cost. I would definitely recommend checking it out!
I've noticed that a number of top universities are offering courses where students are taught subjects relating to Computer Graphics for their CS majors. Sadly this is something not offered by my university and something I would really like to get into sometime in the next couple of years.
A couple of the projects I've found from some universities are great, although I'm mostly interested in two things:
Raytracing:
I want to write a Raytracer within the next two years. What do I need to know? I'm not a fantastic programmer yet (Java, C and Prolog are my main languages as of today) but I'm slowly learning every day. Also, my Math background isn't all that great, so any pointers on books to read or advice on writing such a program would be fantastic. I tend to pick these things up pretty quickly so feel free to chuck references at me.
Programming 3D Rendered Models
I've looked at a couple of projects where students have developed models and used them in games. I've made a couple of 2D games with raster images but have never worked with 3D models. What would I need to learn in regards to programming these models? If it helps I used to be okay with 3D Studio Max and Cinema4D (although every single course seems to use Maya), but haven't touched it in about four years.
Sorry for posting such vague and, let's be honest, stupid questions. It's just something I've wanted to do for a while and something that'd be good as a large project for me to develop in my own time.
Related Questions
Literature and Tutorials for Writing a Ray Tracer
I can recommend pbrt, it's a book and a physically-based renderer used to teach computer science graduates. The description of the maths used is nice and clear, and since it is written in the 'literate programming' you can see the appropriate code (in C++) too.
The book "Computer Graphics: Principles and Practice" (known in the Computer Graphics circles as the "Foley-VanDam") is the basic for most computer graphics courses, and it covers the topic of implementing a ray-tracer in much detail. It is quite dated, but it's still the best, afaik, and the basic principles remain the same.
I also second the recommendation for Eric Lengyel's Mathematics for 3D Game Programming and Computer Graphics. It's not as thorough, but it's a wonderful review of the math basics you need for 3D programming, it has very useful summaries at the end of each chapter, and it's written in an approachable, not too scary way.
In addition, you'll probably want some OpenGL or DirectX basics. It's easier to start working with a 3D API, then learn the underlying maths than the opposite (in my opinion), but both options are possible. Just look for OpenGL on SO and you should find a couple of good references as well.
The 2000 ICFP Programming Contest asked participants to build a ray tracer in three days. They have a good specification for a simple ray tracer, and you can get code for the winning entries and some other entries as well. There were entries in a large number of different programming languages. This might be a nice way for you to get started.
The briefest useful answer I can give is that most of the important algorithms can be found in Real-Time Rendering by Tomas Akenine-Möller, Eric Haines, and Naty Hoffman, and the bibliography at the end has references to the necessary maths. Their website has a recommended reading list as well.
The most useful math book I've read on the subject is Eric Lengyel's Mathematics for 3D Game Programming and Computer Graphics. The maths you need most are geometry (obviously) and linear algebra (for dealing with all the matrices).
I took such a class last year, and I believe that the class was wonderful for forcing students to learn the math behind the computer graphics - not just the commands for making a computer do what you want.
My professor has a site located here and it has his lecture notes and problem sets that you can take a look through.
Our final project was indeed a raytracer, but once you know the mathematics behind it, coding (an inefficient one) is trivial.
For a mathematical introduction into these topics, see
http://graphics.idav.ucdavis.edu/education/GraphicsNotes/homepage.html
Check http://www.scratchapixel.com/lessons/3d-basic-lessons/lesson-1-writing-a-simple-raytracer/
This is a very good place to learn about ray tracing and rendering in general.
So, I use Linux, and I've been trying to find the time to get into game programming. I started out with Panda3d and had some pretty decent results and got a feel for many of the concepts in game programming. Not too long after that, I decided to step it up a notch and go to something more powerful and C or C++ based.
I'm probably just really dumb, but I could never really figure out how to use Crystalspace correctly. If somebody has any useful resources on how to use it, I would appreciate that. But in the meantime, I was messing around with Irrlicht and I like it, but I would like to know what more knowledgable people have to say about the subject. And maybe theres another awesome option out there I don't know about.
If you ask me, Irrlich is the best open source engine - it has clear architecture, good performance and requires lesser code to be written by programmer. I can not honestly compare Irrlicht with Crystal Space or Orge. I consider CS as mess of code, written by many different programmers in different manners - I am hard to imagine how to use it too (due to absolute lack of documentation). As for Ogre, it is not easier than D3D. I've examined different samples and fount plenty multyline fragments of code that are done with a single line in D3D. So, I simply can not see a reason, why to spent months learning OGRE's terrible API - if one has free time, I would advice to learn D3D itself.
I can say even more - Irrlicht is better, than many commercial engines, for example - Torque (absolute lack of documentation, forces to start project over existing one etc.), Truevision etc. Of course, Irrlicht lacks some great features, AAA grade engines must have, but it is quite sufficient for smaller projects.
If you have not BIG money to acquire Gamebryo and similar grades engine, I would advice to stick with Irrlicht - for first several projects at least.
I've spent some time working in the game industry. I'm also a Linux guy. I used Irrlicht to make a couple games, and used those as part of my resume, which helped get me get a job as a game programmer.
Irrlicht has a cleaner API, lower system requirements and works better across platforms than Ogre, in my opinion. I've had a blast making games with Irrlicht. It's also fairly lightweight (much lighter than Ogre), with a very open license for any use, commercial or otherwise.
Working with that engine did a lot to prepare me for working within the commercial game industry.
Ogre3D
http://www.ogre3d.org/
Is typically named together with crystalspace and irrlicht.
Ogre and Irrlicht both are said to have a cleaner design than crystalspace so I wouldn't worry to much about problems with the latter.
If you're looking for productive game development, then my best bet would be to use Unity 3D. I started off by using Irrlicht but quickly backed out because of non intuitive tools and a lot of stress on programming. Ogre seemed to be even more complex.
Unity on the other hand is rapidly gaining grounds with each release. The recent Unity 4 is packed with a ton of features. With very little game dev knowledge, I've managed to write my own flight sim engine in Unity Android. Even learned to write shaders easily.
Though advanced Unity licenses are paid, but they are well worth it. But you can always use Unity free edition to make commercial PC games. In all, game development is all about getting the hang of a game engine. Master any, and you will rule.