This problem is not mine, so I will need some time to provide details.
XY sets up the Java environment for Slick2d programming based on a tutorial video series. XY uses same code as the tutor, but tutor gets 800 FPS and XY gets 5. The application is working as it is supposed to, but it has a major FPS issue. XY uses Eclipse for compiling.
What is worth checking in such a situation?
The first thing that comes to mind is the rendering method XY is using. I do not know about the intricacies of Slick2D rendering, but since it uses OpenGL I can say the difference in performance between rendering methods is huge. If possible, I would try to use display lists or vertex buffer objects. I this this forum post would be helpful.
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Background information
In school we learned 2 languages, Java and Processing
I know that Java and Processing arent the best languages for programming games.
It doesnt cared me ^^ so i started to work on a simple pacman ...
Question 1
Is there something more effective than Sprites/BufferedImages ?
Question 2
For rendering and drawing huge maps, is there a method to do that ?
Normally it would lag when drawing it cause of all the images :)
But how i can render/draw large maps without any fps collapse?
Short answer: Don't bother optimizing before you have a problem.
Longer answer: The most efficient way to do this is by using a game development framework, which handles this kind of thing for you. But really, stick with what you're comfortable with until you actually have a reason to change.
Java and Processing are fine languages for game development. There was a game called Recluse a few years ago that did very well at Ludum Dare (a game programming competition), and it was done in Processing.
On the Java side, there are a ton of very popular game development frameworks. LibGDX is probably the most popular. In fact, the libGDX Jam just happened, and you can check that out for a bunch of examples of what's possible in Java game development. You might also want to check out JMonkeyEngine and LWJGL.
I would say this: program with whatever you're comfortable with. If you're comfortable with Processing and Java and using sprites and BufferedImages, then do that. Don't worry about efficiency until you actually have a problem.
Processing is a great language to make some simple games. Start with Pong and Space Invaders. When you're ready to "graduate" to more complicated games, then check out libGDX. Don't worry about making everything as efficient as possible- focus on finishing games, which is much harder.
You'll also find a very active community of Java game developers on JGO.
Good luck!
Is there something more effective than Sprites/BufferedImages ?
No, not at your level of programming experience.
For rendering and drawing huge maps, is there a method to do that ?
Tiles. Generally tiles are 256 x 256 pixel images of one section of the map. Like floor tiles, you place tiles together until you have a large enough graphic for your view. As the player moves, you add the tiles in the direction the player is moving and remove the tiles from where the player came.
Here's an introduction to creating a tile map engine.
I am currently thinking of developing an MMORPG with a Java Client. It will be a survival sandbox game, with much wilderness.
Now I would like to know if there is any program which can get the loaded world out of the cache of the running client. (as image or something else visible) I need this because the world would be huge and it will help to hand out official maps for the game.
You might want to start by looking into VBOs and VAOs (incredibly fast way of storing vertex, normal, texture... data on the GPU instead of the CPU). I'd also recommend checking out Blender, which I'm sure you've heard of, and their easily readable format known by the OBJ extension (The OBJ extension was developed by WaveFront). There are many libraries that allow you to read these files, but the format is simple enough that you can code an advanced mesh loader in around 80 lines or less.
I'm not entirely sure what you mean by your question about whether or not you can get a world out of the cache, but if you're looking to get 3D data from an image, you can check out height maps. However, height maps are better for general terrain where you will NOT have caves. Generally things like that are loaded from a 3D modeling program's output.
This might go against what other people think, but the best way to start out is by using OpenGL to its potential. Of course this involves implementing your own matrix stack for shaders and so on, but the payoff of easy engine modifications in the end is great. The good thing about OpenGL is even though you might have Java or C++ or some language that you use, the methods remaing (generally) the same. However, the syntax does vary just like the languages do themselves.
Pyglet (Python bindings for OpenGL) is an interesting place to start if you are looking to get started with OpenGL while maintaining ease of programming and quick debugging (because it is an interpreted language) and dynamic typing helps because OpenGL can be picky about the types it accepts.
I have been working on a voxel game for some time now, but all that I have really accomplished was the main menu and an Item system. Now its time to make the voxel engine. I have been searching for a while now to find some tutorials or an ebook that will teach me such, but the best i could find were someones tutorials in c++, but I am making mine in Java. I have dabbled in c++ and c# in the past but it was too difficult to translate i.e. it relied on a class that java doesn't have. What I know is that there are different methods for voxel engines, they all begin with rendering a single cube, and Perlin and Simplex noise can be used to randomize terrain generation.
If anyone could point me in the correct direction, most appreciated.
I will be checking back at least once a hour incase someone feels this thread is dead.
I'm not entirely sure what you are asking, if you are asking how to make simplex noise, implement it in a voxel engine or how to start making a voxel engine.
If you are asking how to start making a voxel engine I would recommend practising with quads first (2D version) and focus on getting an understanding for the theory. Once you are happy with your understanding you should focus on the voxel class (one cube) - it is very important to learn as much as you can from it, and then add more so you can optimize rendering as much as you can, such that hidden faces are not rendered and even vertices are shared, voxel engines can be the most wasteful renderers if not optimized!
EDIT:
Optimization can be done through many methods, The first and most important is hidden face removal, this involves removing the faces of voxels that are touching which will mean you will need to check of a voxel exists on any given side of any voxel before rendering that face (e.g before rendering the left face, check if there isn't a block to the left). Next is the rendering method, do not render each face or each group individually, group them so they can be rendered faster, this can be done by using display-lists or the more technical VBOs, these ensure the data is in the GPU or the data can be given to the GPU faster, For example Minecraft groups them in chunks of huge 16x16x128 groups and uses display lists. If you really want to reduce every single vertex in memory you can also consider using strip drawing methods (in OpenGL), these will require you to define certain vertices at a certain time in rendering but allow you to reuse a vertex for multiple faces.
Next would be understanding simplex noise, I can relate to there not being much material online for noise generation algorithms, unfortunately I cannot link material that I used as that was years ago. You can implement your noise algorithm in the 2D version to prove it works in a simpler environment and then copy it to the voxel version. Typical usage would be to use the values as heights in the terrain (e.g white=255 = 255 high).
I would recommend using Unity. The engine is already made and you can add menus and titles with just a few lines of code. All of the game creation is either in C# or Javascript which shouldn't be any huge change from C++. Good luck!
i was wondering if anyone has knowledge on the recontruction of 3D objects from live video feed. Does any have any java based examples or papers JAVA based that i could be linked to as i have read up on algorithm's used to produce such 3d objects. If possible i would like to construct something such as the program demostrated in the link provided below.
Currently my program logs live video feed.
http://www.youtube.com/watch?v=brkHE517vpo&feature=related
3D reconstruction of an object from a single point of view is not really possible. You have two basic alternatives: a) To have a stereo camera system capturing the object, b) To have only one camera, but rotating the object (so you will have different points of view of the object), like the one in the video. This is a basic concept related with epipolar geometry.
There are other alternatives, but more intrusive. Some time ago I've been working on a 3D scanner based on a single camera and a laser beam.
For this, I used OpenCV which is C++ code, but now I think there are ports for Java. Have in mind that 3D reconstruction is not an easy task, and the resulting app. will have to be largely parametrized to achieve good results.
This isn't a solved problem - certain techniques can do it to a certain degree under the right conditions. For example, the linked video shows a fairly simple flat-faced object being analysed while moving slowly under relatively even lighting conditions.
The effectiveness of such techniques can also be considerably improved if you can get a second (stereo vision) video feed.
But you are unlikely to get it to work for general video feeds. Problem such as uneven lighting, objects moving in front of the camera, fast motion, focus issues etc. make the problem extremely hard to solve. The best you can probably hope for is a partial reconstruction which can then be reviewed and manually edited to correct the inevitable mistakes.
JavaCV and related projects are probably the best resource if you want to explore further. But don't get your hopes too high for a magic out-of-the-box solution!
I would like to implement a visualisation of this video in Java as experience to help me understand all of the 'troubles' in creating visualisations. I have some experience in OpenGL, and a good understanding of how to handle the physics involved. However, if anybody knows of any good game engines that may help (or at least do some of the heavy lifting involved in creating a visualisation of the above) I would be grateful.
Also, I noticed that the linked video must use many separate jets in order to operate in the way it does. Is it likely that it was created using something a little lower level such as C? Is it possible to use a higher level language like Java to control such a system?
Honestly, if you want to implement "just that", I think using a game engine is overkill. Just implement a simple particle engine on your own and you are done.
Seriously, that problem is not so difficult, any language can be used for it. The basic principle behind it is the same as behind steam organs or self player pianos. You have an input data that shows what the pattern to play is and you advance it in a given time.
Here is how I would build the basic control system. You take a black and white image. The width is exactly as wide as the number of "emitters" and the length is as long as the pattern needs to be. You read the image and start at the first line. You walk through each pixel in that line and if the pixel is black you emit a drop and if the pixel is white you don't. You then move in a given interval (maybe 25ms) to the next line and set the emitters accordingly.
The cool thing with images is that you can simply paint them in any graphic program. To get the current time to work you render the time into a image buffer in memory, then pass that into the above code. (You even get fonts if you like...)
You can use jMonkeyEngine.
JAVA OPEN GL GAME ENGINE