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I'm trying to load a car object made with 3DS Max into a JOGL program but I don't know how to do that. I have searched online but haven't gotten a good result.

I tried this but got no result.

Is there a tutorial on how to do that? or how to write your own loader? or an already written class that I can use?

Dan D.
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Joey
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    Welcome to StackOverflow. This is not the correct site to ask for tutorials or for finding existing code. If you start an attempt, we can work with you. – Goose Jan 28 '16 at 16:53
  • @Joey, welcome to StackOverflow! I hope you find this community as helpful and useful as I do. Please take a look at http://stackoverflow.com/help/how-to-ask for info on asking good questions. Also, you can get a quick and easy badge from reading the entirety of the tour page available at http://stackoverflow.com/tour , which will also give you plenty of information useful for people new to the site (like yourself). Have a wonderful day! – Emily Mabrey Jan 28 '16 at 19:33

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Here is a very limited loader for the OBJ format written in Java (but unfortunately using the lower-level LWJGL instead of JOGL) by Oskar Veerhoek as part of the Coding Universe website. You would pass the File object which references your OBJ file into that class using either the loadModel(File f) method or the loadTexturedModel(File f) method. The returned Model object contains the 3D model described by the OBJ file. You should then pass the Model object to the provided utility methods createTexturedDisplayList(Model m), createDisplayList(Model m), or createVBO(Model model). Those return a renderable vertex buffer object or display list which you can then use as part of your render. Note however that you could write your own Model to renderable method if the provided don't meet your needs, but I would highly recommend understanding/reading the provided methods first.

An alternative which is much more full-featured is the joglobj library written in Java using JOGL. This loader is more complete, but it doesn't correctly handle transparency and textures in some ways. Using this loader will require this dependency (which is used to parse the OBJ file).

Another alternative is the oObjLoader library, which "is a java library for parsing and loading WaveFront .OBJ files."

If none of these meet your needs please refer to other similar SO questions, such as this question from user skaffman. Additionally, the gaming development specific stack exchange is a good place to look for similar related questions . This is a question from that section which discusses correctly loading OBJ files.

Community
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Emily Mabrey
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  • I downvote because your very first example doesn't use JOGL whereas there are plenty JOGL based ones and because other solutions that you suggest are based on some obsolete versions of JOGL and are less complete than our build-in loaders. – gouessej Jan 28 '16 at 21:45
  • Your recommendations aren't an answer to "how to write your own loader?" or "[Is there] an already written class I can use [that uses JOGL]?" Why did you criticize the fact I gave an easy to read example class written in low-level LWJGL (essentially a pure openGL solution); your answer includes a recommendation of an Ardor3D class ultimately based upon the ultra high-level jMonkeyEngine. IMO a high-level scenegraph engine is not a good choice for a beginner's example. – Emily Mabrey Jan 28 '16 at 22:29
  • The title of the question clearly mentions "in JOGL" whereas your first example requires both the main competitor of JOGL and Slick (org.newdawn.slick.opengl.TextureLoader) whereas JOGL has its own texture loader. Then, your very first example isn't a pure OpenGL solution. The problem is that loading a model involves some notions that go beyond OpenGL rendering and that shouldn't be implemented in any binding (even JOGL), that's why my very last solution uses a scenegraph API based on JOGL but my very first solution uses only one class of JOGL and the second one uses JOGL-Utils. – gouessej Jan 29 '16 at 08:56
  • Moreover, several members of the JogAmp community (including me) are fed up with people promoting our main competitor in numerous StackOverflow questions. – gouessej Jan 29 '16 at 08:58
  • Sorry, @gouessej, but who? I think you are overreacting ;) – elect Feb 01 '16 at 07:40
  • @elect At least 3 of her references lead directly or not to some examples using JOGL main competitor including her very first example whereas there are some examples using the latest version of JOGL. Using the questions about JOGL to mention a library doing something similar isn't necessary as JOGL just does the right job here as usual. – gouessej Feb 01 '16 at 09:32
  • Then just make her simply notice it, no need to make things tragic or start debating, I guess she didn't do on purpouse since it's always java and translation between them is preatty straightforward ;) – elect Feb 01 '16 at 10:24
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I advise you to read the Wikipedia article on Wavefront .obj file (and MTL), the external links are interesting too, especially the specification, it helps to understand this ASCII file format, its "commands" (v, vf, vn, vt, f, mtllib, usemtl, o, s, g, ...) and its structure.

The other examples I quote can help you to understand how to parse the files and to convert your data into something more "OpenGL friendly" by using a few JOGL classes or more high level utilities.

There are one OBJ loader in JOGL and another one in JOGL-Utils: ObjReader and WaveFrontLoader.

There is the LibGDX OBJ loader too. LibGDX has a non official backend based on JOGL which is actively maintained by @bgroenks, @xranby and me.

You can use JogAmp's Ardor3D Continuation too (which uses JOGL under the hood), you can look at this simple example, its WaveFront OBJ importer (it shows you how to parse an OBJ file) ant its storage (it shows how to store the data into some structures to use them later to draw with JOGL).

N.B: I'm responsible for engine support in the JogAmp community, I'm in the list of the official maintainers and I'm the main contributor of JogAmp's Ardor3D Continuation which isn't a fork of Ardor3D but a "continuation". The development of the legacy Ardor3D was stopped in March 2014 according to its main developer Renanse as stated here on his blog.

gouessej
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  • The recommended Ardor3D library in this answer is a fork maintained by the user who wrote this answer (the GitHub repo gouessej linked is owned by a GitHub user named gouessej). Following the recommendations of this meta post (http://meta.stackexchange.com/questions/15787/how-do-i-mention-my-own-products-in-answers) I'm adding this clarification to avoid anyone not being aware of the self-promotion. – Emily Mabrey Jan 28 '16 at 22:14
  • gouessej went ahead and edited his post by adding a bunch of stuff, including an acknowledgement of the fact he was promoting his own project. I'm going to leave up my other comment, but please note that it is no longer completely accurate due to subsequent edits. – Emily Mabrey Jan 29 '16 at 18:15
  • I completely agree with listening carefully to constructive critics but I wasn't "promoting" my own project (you have forgotten our contributors) and this engine is mentioned only in the very last example even before my numerous subsequent edits. – gouessej Jan 29 '16 at 18:22
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    It's not self promotion if the resources being given are free, open source, and community driven. @gouessej isn't using his repositories to profit or gain from OP's usage of them. He's helping a member of the community use the software. It's only really necessary to acknowledge your own project if it's a commercial product from which you have something to gain. – bgroenks Jan 29 '16 at 21:40
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    He recommended Ardor3D because he was "fed up with people promoting [his] main competitor in numerous StackOverflow questions" instead of simply providing the most correct answer. I dislike undisclosed conflicts of interest so I drew attention to the self-promotion (defined as "... promoting ... one's activities"). However, I realize people might not agree with my opinion, so I only drew attention to the self-promotion and left people to make their own decisions. I wasn't trying to accuse anyone of anything, I was just trying to increase transparency to where I thought it should be. – Emily Mabrey Jan 30 '16 at 04:53
  • You promoted JOGL main competitor purposely or not instead of simply looking for some JOGL build-in Wavefront OBJ loaders in its source code unlike me, I remind you that actually at least 3 of your references lead directly or not to some examples using this competitor. Even the very first version of my answer contains two examples coming directly from JOGL and JOGL-Utils. I edited my answer because I agree with your concern on transparency and I took into account some of your constructive remarks. – gouessej Jan 30 '16 at 10:32
  • However, in my humble opinion, suggesting an alternative (a competitor) whereas there are some viable solutions using the library mentioned in the question and in one of its tags is far from being the best way of answering and this kind of behaviour on StackOverflow and on various popular Java forums is the main reason why several contributors (including me) repeatedly have to encourage the developers to ask JOGL specific questions on the official JogAmp (JOGL, JOCL, JOAL) forum. – gouessej Jan 30 '16 at 10:37