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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12
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2answers
1k views

How do I create a World Healing Wave effect?

I want to change my dark and depressing background to a happy grassy background, in real-time, such that the happy background is shown in a radius around a game character. A forcefield of happiness, ...
7
votes
2answers
517 views

Java single Array best choice for accessing pixels for manipulation?

I am just watching this tutorial https://www.youtube.com/watch?v=HwUnMy_pR6A and the guy (who seems to be pretty competent) is using a single array to store and access the pixels of his to-be-rendered ...
6
votes
5answers
1k views

How to save and restore Bullet Physics state?

I'm looking for information on how to save the runtime state of rigid bodies with Bullet Physics. Most of my world consists of static objects, but I have a few dynamic and kinematic objects as well. I ...
6
votes
5answers
1k views

What is Java missing that might make it difficult to develop fully-featured 2D games?

Without using any external libraries, does Java, including all officially supported APIs give you enough to develop fully-featured 2D games? The reason I ask is that I hear a lot of "bad-mouthing" ...
5
votes
1answer
301 views

Implementing Vehicles in your game

In the game i am creating as an hobby (learning is the primal goal of it all) i plan to implement a space ship that the player can enter and use to explore it. I tried to search the internet for the ...
5
votes
3answers
2k views

GameState management hierarchical FSM vs stack based FSM

I'm reading a bit on Finite State Machines to handle game states (or screens). I would like to build a rather decent FSM that can handle multiple screens. e.g. while the game is running I want to be ...
5
votes
1answer
1k views

What's the best way of drawing a glowing 3d line using LWJGL?

Sort of like a strip-light effect; not actually a light source, but just a polygon with glowing edges. Can this be done easily? Right now I'm contemplating drawing a line more than once with varying ...
4
votes
3answers
1k views

Tetris - Rotations using Linear Algebra (Rotation Matrices)

I'm making Tetris in Java and am at the point of rotations... Originally I was hardcoding each rotation: if (direction.equals("right")) { if (shape.equals("Bar")) { if ...
4
votes
3answers
3k views

How can I make my main character move in a parabolic arc when jumping?

I'm entering Android game development, and I already have a computer version of a game I want to publish. The thing is, I want to make this as good as it can be. With that said, I need a physics ...
4
votes
1answer
821 views

Scaling a game view with letterboxes?

I'm creating an Android game and I want everyone who plays it -- no matter the size or shape of their screen -- to see the same 480x800 playfield but, depending on the actual resolution of their ...
3
votes
2answers
515 views

Is it possible to compile an android game for pc desktop?

If I have an android game based on java native libraries. Is it to possible to compile into a windows/linux executable without a 3rd party emulator?
2
votes
1answer
207 views

Preventing diagonal movement

I was originally fine with diagonal movement but it's clashing with my sprite animation... public void keyPressed(KeyEvent e){ int key = e.getKeyCode(); switch(key){ case ...
2
votes
1answer
765 views

Maintaining velocity of free fall body using Box2D in libGDX

I want to maintain the speed of a free-falling Box2D body using LibGDX. I'd like the vertical velocity increase with the level. I've applied a linear impulse and velocity actually increases like this: ...
2
votes
3answers
1k views

How to find the entity I'm looking at?

I am currently making a mod for Minecraft but I have come to a stop because I am lacking in some knowledge. I need to get data for the entity I am looking at, which I believe requires the use vectors, ...
2
votes
3answers
776 views

Using random numbers with a bias

I appear to be awful at describing the question so I'll try and describe the problem. I want to add a random amount of heads to my creatures but I want to be able to determine several things. a) The ...
2
votes
5answers
851 views

Add delay between player jumps

I'm developing a platformer game and have implemented jumping for the player. The player is able to jump, but holding the up arrow causes the player to continuously jump. What would be the best way to ...
2
votes
1answer
223 views

Is using the applet class in a Java game a wise thing to do?

I am making an 2D multiplayer game in Java project, by using Java sockets and simple java.applet.* Our teacher told us to use J2EE concepts in the project. Do I have to use JSP? Is it better or ...
2
votes
1answer
870 views

Slick2D, Nifty GUI listeners problem

I'm trying to get Nifty GUI to work with Slick2D. So far everything is going great, except that I can't seem to figure out how to properly interact with the GUI. I'm trying the example in the nifty ...
2
votes
2answers
1k views

How should I do 3D games through Java on a mac?

I have been self-teaching myself Java on the mac mostly because the language is cross-platform. Recently, I have been only able to develop 2D games using the Graphics2D class. Now, I want to learn ...
2
votes
2answers
927 views

Tile based map and collision; getting stuck

I'm trying to make my character move around a tile map with collisions. Everything works fine except for one thing. I show you a picture with the problem: http://i.stack.imgur.com/ZWI7x.jpg That is, ...
1
vote
1answer
39 views

In JBox2d when dragging a Body, why is the direction is flipped vertically?

Why is it when I drag a JBox2d Body with the mouse, the vertical component is flipped? e.g. If I drag down-right, the Body moves up-right. Is this expected behaviour, a bug in JBox2D, a Mac ...
1
vote
1answer
138 views

Restarting a libGDX game to apply changes to resolution

How can I restart a LibGDX game to apply certain changes to the game such as changes to the resolution (going from 1920X1080 to 1280X720), or changing full screen. Granted the resize(int width, int ...
1
vote
2answers
158 views

How to make an Actor follow my finger

I'm back with another question that may be really simple. I've a texture drawn on my spritebatch and I'm making it move up or down (y-axis only) with Libgdx's Input Handler: touchDown and touchUp. ...
1
vote
1answer
81 views

Electronic circuit simulator four-way flood-filling issues

I've made an electronic circuit board simulator which has simply 3 types of tiles: wires, power sources, and inverters. Wires connect to anything they touch, other than the sides of inverters; ...
1
vote
2answers
303 views

Movement doesn't look smooth (slight lag)

Currently I'm using a variable time step and when the FPS drops by even a small amount you can easily notice a slight lurch forward of the player. I'm making a platformer and I'm wondering whether I ...
1
vote
2answers
799 views

How to check for cube collisions?

I want a method, which takes two "ObjectBox" objects (A "ObjectBox" has .getX() .getY() .getZ() .getSizeX() .getSizeY() .getSizeZ() methods) as a parameter and return true if the two Boxes are ...
1
vote
3answers
2k views

How can I remove enemies from my ArrayList after they have died? [duplicate]

Possible Duplicate: How do I best remove an entity from my game loop when it is dead? Right now, I have an ArrayList like this: List<Enemy> enemies = new ArrayList<Enemy>(); ...
1
vote
1answer
1k views

Moving sprites on a graph in libGDX

In my game I'd like to move sprites on a fixed path. Until this point I was trying to stick with the tools already provided by libGDX, like the Tiled map renderer classes so I'm looking for a solution ...
1
vote
1answer
2k views

LWJGL - Mixing 2D and 3D

I'm trying to mix 2D and 3D using LWJGL. I have wrote 2D little method that allow me to easily switch between 2D and 3D. protected static void make2D() { glEnable(GL_BLEND); ...
1
vote
1answer
399 views

Color based collision detection

I am making a game where you fly a ship around some randomly generated planets. Since I am using a for loop to draw over 5000 planets, using the rectangle class or an oval-type class for this is not ...
1
vote
2answers
363 views

How do we adapt our game to work over a network?

A friend of mine has made a Java version of a popular board game in Java, and has it working for multiplayer on one PC with different turns for each player. He's mentioned he wants it to eventually ...
1
vote
2answers
2k views

Dynamically load images inside jar

I'm using Slick2d for a game, and while it runs fine in Eclipse, i'm trying to figure out how to make it work when exported to a runnable .jar. I have it set up to where I load every image located in ...
1
vote
1answer
761 views

MMO Proxy Server

I am building an MMO and someone told me I should never have my application interfacing directly with the net, and that I should have a local proxy. This makes sense, with security issues and scaling ...
1
vote
4answers
1k views

Client server design question

I'm working on creating a multiplayer game, with the client in ActionScript and the server written in Java. I'm using XMLSocket in the client to connect to the server. The server code looks something ...
1
vote
2answers
631 views

What are some good resources on creating and reading 2D game levels in Java?

Could some resources be listed in relation to the creation and management of simplistic, efficient 2D game levels, that are available for use with Java?
0
votes
1answer
212 views

How do I decompile Minecraft?

I'm trying to get started modding Minecraft. I opened up the minecraft.jar file in Eclipse, but it doesn't contain what I expected. In this tutorial the presenter decompiles minecraft.jar and finds ...
0
votes
0answers
65 views

Slick2D/LWJGL Drawing coloured lights problem

I am using the Slick2D engine. I've followed this snippet for creating light sources. I have followed step step, added what is actually important for me, and tested it and the lighting effects ...
0
votes
1answer
81 views

(LWJGL) Exporting Textures with JarSplice [duplicate]

I have another game that uses rectangles instead of textures and works just fine. when I run this I get this error: Microsoft Windows [Version 6.1.7601] Copyright (c) 2009 Microsoft Corporation. ...
0
votes
1answer
63 views

Actors (Label) not being drawn to stage [closed]

I have a weird issue that when I try to draw a Stage with only an Actor, a Label to be more precise, added to it and nothing seems to be getting drawn. This is how my setup goes: I have a Sprite ...
0
votes
2answers
524 views

Using System Time to compute delay times that correctly deal with app pauses?

In my Android app I have the requirement to introduce small (for slowing down animation) and larger delays (for the purpose of delaying the appearance of a character for example). I've experimented ...
0
votes
0answers
35 views

Bounding box should rotate - Skews instead [duplicate]

I have a method to rotate a sprite's bounding box around the center of the sprite (the sprite rotates and I need the bounding box to rotate with it. The sprite is rectangular). Instead of being ...
0
votes
1answer
99 views

Is it possible to display no white images/sprites when using the latest Android OS?

Was it okay to use Texture.setEnforcePotImages(false) in order to disable conditional width and height pixel size that requires power of 2? I'm planning to sell the game app at Google Play. I want to ...
0
votes
2answers
2k views

Java collision detection with rectangles

I'm trying to get the collision between two squares. I've made a Rectangle object that overlays each one and updates the position every tick. Then I made a collision method that checks whether they ...
0
votes
3answers
403 views

Tile Map World Background

I am making a 2D top-down game in Java using the Slick2D library. However, this question applies to all ways of making games of this nature. My question is: How would I do a background for the world. ...
0
votes
1answer
469 views

Get back or delete an existing OpenGL object, then change it and draw at new. How?

With OpenGL i'm drawing for example a circle. Can i take this drawn circle back out of the window and change something and then draw it back on the window? Or can i /have to delete it and then draw ...
0
votes
2answers
187 views

Draw Rectangle To All Dimensions of Image

I have some rudimentary collision code: public class Collision { static boolean isColliding = false; static Rectangle player; static Rectangle female; public static void collision(){ Rectangle ...
0
votes
1answer
158 views

Gravity stops when side-collision detected [closed]

Please, look at this GIF: The label on the animation says "Move button is pressed, then released". And you can see when it's pressed (and player's getCenterY() is above wall getCenterY()), gravity ...
0
votes
3answers
310 views

GO Game, placing stones on grid intersections

I'm currently making a GO game and I am stuck on the most basic functionality. That functionality is being able to click on the intersections of the grid and ONLY the intersections to place a stone, ...
0
votes
1answer
363 views

How do I get the current location when using slick 2D library?

I'm developing a map kind of simple game using slick 2D library, and I want to get the current location of the user. When the user runs into a special location (ex: hole) to indicate that is ...
-1
votes
1answer
210 views

Grid based Collision Detection between circles [duplicate]

I am working on a 2d arcade game where I have 5 types of circles with different sizes: The ship, the missiles, and 3 types of monsters. This is what it looks like: Currently I'm using brute force ...