Java is both a popular programming language and runtime environment which allows Java programs to run unchanged on most hardware and software platforms.

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6
votes
2answers
7k views

How do you determine which object/surface the user's pointing at with lwjgl?

Title pretty much says it all. I'm working on a simple 'lets get used to lwjgl' project involving manipulation of a rubik's cube, and I can't figure out how to tell which side/square the user's ...
46
votes
8answers
36k views

Is Java viable for serious game development? [closed]

Ever since I was a little kid, my dream has been to develop games. Well, now that I am older, more mature, and have some programming experience, I would like to start. However, I would like to turn ...
4
votes
2answers
8k views

How can I move a sprite in the direction it is facing?

I'm using Java/Slick 2D. I'm trying to use the mouse to rotate the sprite and the arrow keys to move the sprite. I can get the sprite to rotate no problem, but I cannot get it to move in the direction ...
3
votes
1answer
260 views

LWJGL Eclipse Resource Deployment

I'm still experimenting with some OpenGL in LWJGL, and as I get to know more and more about OpenGL, I start to do more complicated things like multi texturing, shadowmapping and more. Now, right now ...
10
votes
3answers
8k views

Is there an algorithm for a pool game?

I am looking for algorithm to calculate direction and speed of balls in a pool game. I am sure there has to be some type of open source code for this since pool games are some of the oldest computer ...
12
votes
1answer
605 views

When and why is a Pool class needed to hold objects?

I've been studying opengl es and an example I saw was using a "Pool" class to keep track of touch and keyboard events. Could someone please explain how and why a pool class is needed. From what I was ...
5
votes
4answers
2k views

Which Side Was Hit?

I am working on an Android game and I have two objects A and B (both rectangles) and when they collide I simply want to know which side of B was hit. I have detected the collision fine, but I am ...
4
votes
3answers
3k views

Why is my velocity decaying?

Programming in Java. Tinkering around with physics. My entities all have position and velocity. In the main loop, all I'm doing is applying gravity and bouncing off the edges, like so: // add ...
4
votes
3answers
2k views

How to Align Gun with Bullets

I have a top-down 2D shooter. I have an image of a player holding a gun, that rotates to face the mouse. Please note that the gun isn't a separate image tethered to the player, but rather part of the ...
12
votes
1answer
11k views

Making a HUD/GUI with OpenGL (LWJGL)

I'm at the stage in my game development where I need to make a HUD or GUI. I've never gotten to this part, so I don't know how its done. I tried rendering a simple quad at a fixed position on the ...
4
votes
4answers
7k views

How to add a scrolling camera to a 2D Java game?

I am attempting to create a game where the camera follows the player, always making sure the player is in the center of the screen. How would I go about this? This game is a 2D Java game, made with no ...
4
votes
3answers
1k views

How can I change this isometric engine to make it so that you could distinguish between blocks that are on different planes?

I have been working on an isometric minecraft-esque game engine for a strategy game I plan on making. As you can see, it really needs some sort of shading. It is difficult to distinguish between ...
2
votes
3answers
2k views

libgdx - collision detection with tiled map java

currently, I am working on a 2d rpg game which is similar to final fantasy 1-4. I can load up a tiled map and the sprite can walk freely on the map. However, I will like to create a wall for it to ...
-5
votes
4answers
3k views

How to implement a 2d collision detection for Android

I am making a 2d space shooter using opengl ES. Can someone please show me how to implement a collision detection between the enemy ship and player ship. The code for the two classes are below: ...
32
votes
6answers
6k views

What is a good file format for saving game data? [closed]

I need to save some custom game data. Map, player, etc. All of them will have "sub objects". For example, a map and map will have an "array" of tiles. ie, hierarchical data. Hopefully nothing ...
17
votes
3answers
6k views

Polling vs event driven input

I'm developing a game using polling for the input method. However, now that I'm delving deeper into the game menus and other UI components, I'm finding that I'd probably like to have event driven ...
2
votes
2answers
4k views

Arc'd jumping method?

Okay, so I'm making a platformer, and I wanna know how I can make a arc'd jump easily. Like what Mario does in super Mario Bros 1. Any ideas on a simple way to accomplish this?
6
votes
2answers
4k views

Breakout Collision: Detecting the side of collision

I am writing a breakout clone (my first game) and am totally stuck as to how I figure out which side of the brick was hit. I have a collision detection method that looks like this: ...
2
votes
1answer
505 views

How do I use a JBox2D ContactListener to check if my character is standing on the ground?

I want to know when my character is touching a wall or floor. I've had no luck searching for information on this. I saw a few things about ContactListeners and getContactList(), but I don't understand ...
7
votes
2answers
6k views

How do I find the angle between two vectors?

I have 3 points on my screen: a = a point which is (c.x, 0) makes a line pointing straight up b = a user input touch, can be anywhere on the screen c = a moving object a _______.________ | ...
6
votes
1answer
592 views

Appropriate level representation / data stucture for a 2D platfrom game?

I'm about to program a copy of Mario in Java. I'm thinking on 2 representations/data structures for the levels but I'm not sure which one should I choose: A 2D integer array. A quadtree to divide ...
6
votes
2answers
2k views

How to store 2D tile-map

I want to create a 2D map composed of small tiles, that should look like voxels (eg. this just from side). I think I can make a structure like Voxel2D, that have int X, Y and some Color, and every ...
3
votes
2answers
2k views

Can you help me find resources for developing a top-down 2D game in Java? [closed]

I just started reading about games, and I'm going to develop a game where a person is moving around on a 2D map. My preferred language is Java. Is that suitable to develop games? I'm going to ...
2
votes
1answer
2k views

3D Camera Rotation

Please, forgive me, but I need help and I've been stuck on this for a few weeks now, I'm making no progress and everywhere I go and I see a different answer, everything I try doesn't work. I've had ...
2
votes
1answer
281 views

When should I load assets for optimal performance?

I'm writing a game using LWJGL and Java, and was wondering if there were best practices for when to load resources. I have seen examples that load all resources when initializing the game (XNA), ones ...
1
vote
1answer
2k views

Making an efficient collision detection system

I'm very new to game development (just started 3 months ago) and I'm learning through creating a game engine. It's located here. In terms of collision, I know only brute-force detection, in which ...
1
vote
2answers
2k views

Adding a short delay between bullets

I'm having some trouble simulating bullets in my 2D shooter. I want similar mechanics to Megaman, where the user can hold down the shoot button and a continues stream of bullets are fired but with a ...
13
votes
1answer
4k views

A* navigational mesh path finding

So I've been making this top down 2D java game in this framework called Greenfoot and I've been working on the AI for the guys you are gonna fight. I want them to be able to move around the world ...
14
votes
8answers
4k views

How do I create tileable solid noise for map generation?

Hey guys, I'm trying to figure out how to generate tileable fractals in code (for game maps, but that's irrelevant) I've been trying to modify the Solid Noise plug-in shipped with GIMP (with my ...
10
votes
2answers
3k views

How do I tackle top down RPG movement?

I have a game that I am writing in Java. It is a top down RPG and I am trying to handle movement in the world. The world is largely procedural and I am having a difficult time tackling how to handle ...
10
votes
5answers
2k views

2D Game dev and Java. Other possibilities than OpenGL?

I recently startet to programm some basic OpenGL stuff in Java, but OpenGL and DirectX is to much to handle and to understand for me and i'm getting bored really fast. Now i am wondering if there are ...
9
votes
3answers
13k views

Fitting Android game to different screen sizes

I am making an Android game that is only in portrait screen orientation. It works great when I run it on my phone, but when I run it on a tablet, even though the screen size is bigger, all of the ...
5
votes
4answers
6k views

2D Platformer Collisions

I've basically asked this question before, and I know it's been asked probably a billion times, but I still can't seem to do it. All I want to know is how I should go about doing basic 4-way, ...
4
votes
4answers
22k views

Android game scrolling background

I'm just trying to figure out the best approach for running a scolling background on an android device. The method I have so far.... its pretty laggy. I use threads, which I believe is not the best ...
13
votes
2answers
1k views

How do you handle uneven tiles while rendering a tile map?

Here is what I want to do with my tile map that I am unsure of. As you can see the top walls are way larger then the bottom and side ones (this is also an issue with my corners which are odd shapes ...
8
votes
3answers
1k views

Android threads trouble wrapping my head around design

I am having trouble wrapping my head around game design. On the android platform, I have an activity and set its content view with a custom surface view. The custom surface view acts as my panel and I ...
7
votes
5answers
2k views

How can I mark levels as “complete” in a way that prevents cheating?

My first thoughts about marking levels complete is to just write the information to a file upon level completion and load that in once the app is opened up again. But how could I keep this safe from ...
7
votes
2answers
3k views

Server side game loop

Many java games use thread.sleep() to controll fps. Since the server does not display graphics, should the server game loop keep running just calculating delta time? Like this example: long ...
6
votes
3answers
3k views

How do I make an entity move in a direction?

I have an Entity instance which is updated every game tick. Let's just assume that entity moves forward constantly. I'd like to be able to give the entity's angle to a function that makes it move in ...
2
votes
2answers
1k views

Making a player move to my mouse when clicked?

How can I get my player to move to the mouse when it is clicked (like in Warcraft)? So far I have tried: if (Mouse.isButtonDown(0)) { if (X < Mouse.getX()) { X += Speed; } if ...
2
votes
2answers
1k views

No LWJGL in java.library.path

Okay, so I know I need to set the path to the native files. I can do this in Eclipse, by going to the VM arguments and using -Djava.library.path=, but when I export, it says that the VM arguments ...
7
votes
2answers
3k views

How to handle pixel-perfect collision detection with rotation?

Does anyone have any ideas how to go about achieving rotational pixel-perfect collision detection with Bitmaps in Android? Or in general for that matter? I have pixel arrays currently but I don't know ...
5
votes
1answer
2k views

Smooth movement in a tile based game

How can we make our character move smoothly across tiles? He moves tile by tile, but that looks unprofessional. In addition, when you hold down the arrow keys he zips across the screen. How can we ...
3
votes
1answer
8k views

How can I make a sprite-sheet-based animation system? [closed]

I want to make animations based on a sprite sheet, but I'm stuck implementing it. The key things I need my code to do are: Play through a set of images once (e.g. a jump animation) Loop through a ...
2
votes
3answers
5k views

Where can I find tutorials for LWJGL? [closed]

I don't know if this is against the FAQ so if you close this, it'll be no surprise. I have done research but all the tutorials I have seen have been to hard to follow; I reckon there are better ones ...
-4
votes
1answer
850 views

How to properly scroll a 2D tilemap?

Hello and I'm trying to make my own game engine in Java. I have completed all the necessary ones but I can't figure it out with the TileGame class. It just can't scroll. Also there are no exceptions. ...
13
votes
6answers
2k views

Am I hurting myself by not knowing C++ for game design?

Right now, I feel I am strong in both Java a C#. (Not much of a leap from one to the other really). While I don't expect a game designer/programmer is an attainable goal early on in my career, This ...
9
votes
3answers
4k views

How to move an object along a circumference of another object?

I am so out of math that it hurts, but for some of you this should be a piece of cake. I want to move an object around another along its ages or circumference on a simple circular path. At the moment ...
9
votes
3answers
7k views

Mods for Minecraft Server - how does it work?

Minecraft server comes as a single jar. How are mods developed? How do they interact with the original jar? What is there under the hood? What technologies are involved there? I'm mostly a C++/Python ...
6
votes
1answer
4k views

Making a camera in a 2D game (glOrtho)

I'm trying to make a camera that follows my character and it seems I've managed. However, I don't know how to limit that my camera don't follow me when my character reachs the boundaries of the ...