I'm reading "Beginning Java Game Programming 2/e" and the book heavily emphasizes using AffineTransform.
There is just one problem, it doesn't explain at all what it is, what it does, and the purpose of AffineTransform.
I have done some google searches, but they're just showing me matrix math... Could someone point me in the right direction?
That's because an affine transform is matrix math. It's any kind of mapping from one image to another that you can construct by moving, scaling, rotating, reflecting, and/or shearing the image. The Java AffineTransform class lets you specify these kinds of transformations, then use them to produce modified versions of images.
Answer is years late, but if anyone else is struggling with this then I recommend reading Introduction to 3D Game Programming With DirectX 11 by Frank Luna. It is a very good book. Though book is about DirectX 11 the first three chapters are just about the math concepts needed for graphics. The chapters explains the math well and provided lots of exercises to practice the topics at the end of the chapter. (You may doing 2D games but the math is the same, the vectors and matrices have just one less dimension.)
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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 trying to implement a small recognition program, which should take an image with hand-written shapes as an input (shape objects can be nested), and tell me which shapes it consists of, their type, size and at least coordinates of one point in a shape.
Where should I start?
Maybe, some machine learning technics could be used for such a task?
I've tried to look for some examples or tutorials dealing with handwriting recognition of custom shapes, but haven't found something worth looking at.
I think you should take a look at Coursera Machine Learning course taught by Andrew Ng from Stanford.
It will guide you through techniques of ML resulting in writing your own digit recogniting neural network.
It's really deep field and I believe that simply using some tutorial will be not enough - understanding of subject and techniques that you will use is really important.
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.
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 need to write a very simple 3D physics simulator in Java, cube and spheres bumping into each other, not much more. I've never did anything like that, where should I start? Any documentation on how it is done? any libraries I could re-use?
Physics for Game Programmers By Grant Palmer (not Java)
Phys2D (Java code)
Assuming you want to get started on how to do it, best way to start is with a Pen and Paper. Start defining focal points of your app (like the entities sphere, cube etc, rules like gravity, collision etc, decide hierarchy of objects etc..)
If you know how to do this, and want a primer on the technology side, Swing is a good option to make UIs in Java.
Also take a look here: http://www.myphysicslab.com/
NeHe's lesson 39 is a good starting point, it's in C++ but the theory is pretty easy to understand.
A nice java physics library is jmephysics (http://www.jmonkeyengine.com/jmeforum/index.php?topic=6459); it is quite easy to use and sits on top of ODE (http://www.ode.org/) and jmonkeyengine (http://www.jmonkeyengine.com) which gives you a scenegraph (http://en.wikipedia.org/wiki/Scene_graph), again something that you'll need for anything beyond a very simple 3d application.
I haven't used it for some time though, and see that they haven't released since late 2007 so not sure how active the community is now.
How about first defining a class for physical object? It has position, velocity, mass and maybe subclasses with other features like shape, elasticity etc.
Then create an universe (class) where to place these physical objects. Sounds like fun :)
If you all you need to simulate is spheres/circles and cubes then all you need is a bit of Vector math.
Eg to simulate a simple pool game each ball (sphere) would have a position, 3d linear velocity and 3d linear acceleration vector. Your simulation would involve many little frames which continually updates each and every ball. If two or more balls collide you simply sum the vectors and calculate the new velocities for all balls. If a ball hits a wall for instance all that is required is to flip the sign of the ball to have it bounce back...
If you want to do this from scratch, meaning coding your own physics engine, you'll have to know the ins and outs of the math behind to accomplish this. If you have a fairly good math background you'll have a headstart otherwise a steep learning curve is ahead.
You can start on this community forum to gather information on how things are done:
gamedev.net
Ofcourse you could use an opensource engine like Ogre if you don't want to code your own.
Check out bulletphysics. bulletphysics.com is the forum or check out the project on Sourceforge.