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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2
votes
2answers
229 views

Poor mobile performance when running from Eclipse

So after weeks of thinking my rendering code was bad, I accidentally discovered the following: Running my game on a Nexus S From Eclipse (Debug as -> Android application): 12fps From the device ...
4
votes
1answer
153 views

How do I make a cube move by rolling?

I am learning jMonkeyEngine by making some small games with it. I have a simple rectangular cube that I want the player to be able to roll around the game world. When he presses the arrow keys, the ...
1
vote
1answer
43 views

How can I check for key releases between keyReleased callbacks?

Slick2D's Input class has a isKeyPressed() method that returns a boolean value according to whether the specified key has been pressed. I want to check if a key has been released in the same fashion. ...
0
votes
1answer
60 views

Run menu in gameloop or as activity?

Currently I am running my menu (with buttons "new game" and "choose level") as an xml view of an activity, that then starts my gameactivity with custom view run on a gameloop. But Im starting to see ...
0
votes
1answer
99 views

Data structure fo a ship like in Faster Than Light

I am wonder me, whats the best data structure for a ship like in FTL. At first I thought its easy and I need only to make a array with the rooms(Tiles). But than I noted, that I must put somewhere the ...
0
votes
0answers
30 views

How can I draw a part of a texture in slick2d?

I know the method for drawing a region of a texture in slick2d: image.draw(x, y, srcX, srcY, srcX2, srcY2); But I have no idea how the texture coordinates work. To draw a region of x:16, y:16, ...
4
votes
1answer
227 views

unable to launch LibGDX Particle Editor.jnlp

I am not able to launch LibGDX ParticleEditor.jnlp file on my system(win7 64 bit) with java7. when I execute this file with javaws.exe in jre7/bin folder, it displays splash screen of badlogic games ...
0
votes
2answers
126 views

Tile map collision and object handling

I want to program a game. In this game there is a tile map and objects that interact with it and them self. For that I made first a TileMap class, in it is only the data of the tile map. Its a very ...
1
vote
1answer
87 views

Change game from portrait to landscape dynamically

I have multiple classes that implement Screen. I want to, say, have the Main Menu screen portrait, then the Play Screen landscape. Is there anyway of changing the orientation dynamically? I thought ...
1
vote
1answer
95 views

How should I implement a Game Over menu in Android?

By Game Over menu, I mean a menu displayed when you die, with an option to play again. I have two approaches in mind: Use OpenGL Have some button textures ready. When the character dies, draw ...
1
vote
1answer
54 views

Libgdx Get Font Height with a Wrap

is possible to get the 'Height' of a font drawed with the drawWrapped methods (with a wrapWidth) ? getMultiLineBounds only works when \n is used, but when drawing with drawWrapped it doesn't give the ...
1
vote
1answer
75 views

How to make platforms spawn without touching other platforms

So I am making a doodle jump like game where there are platforms scrolling by but right now how I have platforms spawning is completely random. I would like the platforms to be spread apart so they ...
0
votes
1answer
158 views

how to implement A Star path finding on 2D map with large tiles

The map tiles I have im my game are 64x64 pixels, and the characters are 16x16 pixels. I was reading about A Star path finding and I was wondering if I need my tiles closer to the size of my ...
2
votes
2answers
121 views

How can I create delays for sprite animations that work correctly when the application is killed and restored?

Please see my original question here: How should I use system time to compute delay times without stutters? In summary, I am attempting to to introduce a delay (say of 5 seconds or so) before a ...
-1
votes
1answer
40 views

Stop diagonal selection in my Match-3 game [duplicate]

I have a matching game where the user drags their finger over items to select them. The problem is, i only want the user to be able to select items by dragging vertically or horizontally, not ...
0
votes
0answers
27 views

Java JOGL NEWT Window without FPSAnimator

how I am new to OpenGL and especally with JOGL. I currently try to learn JOGL. I dont like to create a special thread that runs the display method of my window, so I called it manually. public static ...
1
vote
2answers
116 views

Circular dependency when creating entities

I have the following problem: I have a a class called Stage, that keeps an list of entities, which it iterates over every update loop, and updates them. One of these entities might be a weapon (PEW ...
0
votes
2answers
165 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
81 views

Polygon Collision Response

I'm working on a game engine that has a built in custom physics engine (I know it's a waste of time, but I have years to make this, so why not make it good?). Currently, with any number of polygons, ...
0
votes
1answer
192 views

Fog Of War - Is looping over every tile inefficient?

I'm trying to optimize my static FOW code for my 2D tile-based game and the bottleneck seems to be in the rendering of the fog (rather than the circle drawing algorithm or other aspect of the code). ...
2
votes
3answers
131 views

How do I implement Breakout's “multiball” powerup?

I'm just starting out and making a breakout clone as my first game. I'm implementing all kinds of powerups, but I'm stuck on multiball. The powerup adds additional bouncing balls to the game. So far, ...
0
votes
1answer
82 views

Strange collision in Breakout [closed]

My Breakout game works fine so far, but I struggle with the collision detection... Well... just with the collision from the ball with the brick... Here's the relevant code: List<Brick> ...
0
votes
1answer
106 views

Storing attributes in static geometry

I have a Minecraft like world where I statically create one instance of each tile type, and then place it around the world. However, I don't know how to actually change individual attributes for each ...
0
votes
2answers
76 views

Slick2D: constructor vs. init method

What is the difference between the constructor of a BasicGameState and the init method? It appears that they are both called at the same time when the BasicGameState is registered in StateBasedGame, ...
0
votes
0answers
43 views

Java Angle Math: Calculate how near the player looks to an entity [duplicate]

I am programming a Minecraft Bukkit plugin and need a way to calculate an input number from 0 to 360 for displaying a custom compass / radar. So if the player directly looks at the object (shouldn't ...
-2
votes
2answers
229 views

Why can't I set a single value in a game map Java 2D array? [closed]

I'm trying to set one character on 2D array. map[0][2] = "0"; However, I'm getting 11011 11011 11011 11011 ... I was expecting 11011 11111 11111 11111 ... What am I doing wrong? another ...
0
votes
1answer
69 views

How do I double-buffer renders to a JPanel?

I'm trying to make a little breakout game with Java and Swing. The only issue so far is that drawing on the JPanel causes lots of flickering! The relevant code: JFrame frame = new ...
1
vote
0answers
221 views

OpenGL: Attempt to allocate a texture too big for the current hardware

I'm getting the following error: java.io.IOException: Attempt to allocate a texture to big for the current hardware at ...
0
votes
0answers
50 views

LWJGL Rotating is moving

I am trying to rotate my QUAD even just a little bit. I have read pages like http://www.java-gaming.org/topics/lwjgl-tutorial-series-moving-and-rotating-triangle/30679/view.html In my render() ...
0
votes
1answer
68 views

What's the best way to time a character AI movement on android/java?

I'm creating an android game and I'm trying to figure out the best way to time a character position change, something like this: public void move() { //this.posX += 5; this.posY += 5; if ...
1
vote
1answer
38 views

Slick2D: Initializing graphics object before game loop

I'm using the Slick2D Java game library and I want to set the scale of the graphics object that gets passed to the render method in my game loop. I'd like to do this outside the render method, so ...
1
vote
3answers
320 views

Why does my collision implementation cause my player to “bounce” when a collision occurs?

I have a player polygon and I check to see if it's colliding with my tiled map with this method: public static boolean playerCollisionWith() { for(int i = 0; i < Blockmap.entities.size(); i++) ...
2
votes
1answer
181 views

How to implement a multi-platform Java 2D game engine's graphics?

I'm not sure whether this question should be posted here. I'm trying to make a basic generic game engine in Java. Here's what I have so far. public abstract class Device { public abstract void ...
0
votes
0answers
21 views

Box2D Joints Disconnect

I'm trying to make a soft body physics system using rigid bodies in a circle. I'm having a problem where my joints only connect to one of the bodies, and seems to disconnect from the others. I think ...
11
votes
2answers
755 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, ...
0
votes
1answer
46 views

One InputProcessor for two controllers

On my screen I want to display two controllers, one to turn around the character (We'll call itLook) and one to move the character (We'll call it Move). I have a line registering a ControllerListener ...
5
votes
2answers
457 views

Physics in my game confused after restructuring the Game loop

I'm on my way with making a game in Java. Now I have some trouble with an interpolation based game loop in my calculations. Before I used that system the calculation of a falling object was like ...
1
vote
2answers
2k views

LibGdx drawing weird behaviour

I am finding strange behaviour while rendering TextureRegions in my game, only when pausing it. I am making a game for Android, in Java with LibGdx. When I comment out the line "drawLevelPaused()" ...
2
votes
2answers
137 views

How do I create a horizontally centered “gravity line”?

Here's my ideal scenario: A game object (in blue) can change its horizontal velocity, but it will be pulled back by gravity (dotted gray arrows) toward a central vertical line (in red). How can I ...
0
votes
1answer
197 views

Can I programmatically generate textures in java?

Is it possible to programmatically generate textures in Java, textures that could then be used to cover in game objects?
1
vote
2answers
189 views

Should game objects draw themselves? [duplicate]

Assuming you have classes like Player, Enemy, Map and Tile. The first approach to structuring rendering code would be to give each a render() method and let it draw itself: void render(){ ...
0
votes
1answer
72 views

Calculate The Proper X and Y Coordinate

I have a class called Tile, the constructor takes an integer that represents the tile's type. You can load a tileset ( via loadTileset() ) which initalizes the fields - tileset numOfTiles tileWidth ...
0
votes
2answers
139 views

Create a tornado like particle movement, based on velocity

For context i'm using Java and Minecraft Forge, however the concept should be fairly standard. To spawn particles you use this function... world.spawnParticle("largesmoke", posX, posY, posZ, ...
-2
votes
2answers
67 views

How to calculate a bounding rectangle of a polygon?

Polygon poly = new Polygon(); poly.getPoints().setAll(5d, 15d, 15d, 25d, 5d, 30d); How do I calculate the Polygon's height and width? There is no poly.getWidth() or poly.getHeight() method in ...
0
votes
1answer
140 views

How do I move the camera in 2D LWJGL openGL?

I am making a top-down rpg game with the LWJGL but I can't figure out how to make the camera follow the player. I've tryed using GLU.gluLookAt() but it seems to be designed for 3D and when I try it ...
-1
votes
2answers
37 views

LWJGL Jumping Down [closed]

I'm currently building a little game using LWJGL, and I got a Game class which contains my game loop, instances etc... And a Player class which contains a constructor (for x and y coords), logic ...
0
votes
1answer
112 views

LWJGL Camera Rotation Issues

I am quite new to LWJGL and OpenGL and I am trying to create an FPS camera. I had no problem with 2D stuff, so I decided to step things up and try and make some things in 3D. I have this 3D camera ...
0
votes
1answer
137 views

Game Structure in depth [closed]

I've been curious about game structure for some time now. Does everyone who is a game programmer come up with there own approach to structure there game, or is there like some sort of defined layout. ...
1
vote
2answers
77 views

What caused rotation in exported blender model to jMonkey? (OGRE)

First off, I am very new to jMonkeyEngine 3 and still learning. Not exactly sure what could be causing my snowman to have already been rotated before import. I created him in blender and it was facing ...
5
votes
2answers
364 views

How does this formula for generating water waves work?

I have been trying to implement the wave equation described in this paper ("Water Simulating in Computer Graphics," Kai Li and Liming Wu) in Java. Part of the paper discusses modeling waves as a sum ...