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

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Multi threaded game - updating, rendering, and how to split them

From the StackOverflow post (it was recommended I move this): So, I'm working on a game engine, and I've made pretty good progress. However, my engine is single-threaded, and the advantages of ...
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MMORPG server-side java architecture

I am currently making a MMORPG game, which is turn-based. The client is supposed to run on Android. Now, my friend is doing the graphics, and I have been doing the game classes (player, weaponry, ...
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Tiled based map collision detection problem

I'm working on a tile-based Mario clone. This works all fine when walking and falling. But when the player jumps near a wall and walks to the right in the air, then the player get stuck on the wall. ...
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BitmapFont - where is getBounds method in new 1.6 libGDX

I download newest libgdx version 1.6 and i cant solve problem with center my BitmapFont text. Earlier in version 1.54 i used getBounds() method to find out width of text. Share your solutions, thanks ...
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Why can't I patch my procedural terrain together?

I figured out how to implement a midpoint displacement algorithm to generate a map for my game. I wanted to create an infinitely large world, so I tried to patch two maps together, but they didn't ...
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Problem when scaling game screen in Libgdx

Currently, I'm able to scale the screen by applying this bit of code onto an OrthographicCamera Camera.setToOrtho(true, Gdx.graphics.getWidth() / 2, Gdx.graphics.getHeight() / 2); But something ...
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1answer
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Is libgdx fit for 2D game development on Android or are there simpler alternatives?

I'm looking for a Java framework to develop 2D games on desktop and Android. I've looked at Slick and I really like the API, however the developer himself says if you want a framework for Android and ...
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Efficient 2d Java Line of Sight for a lot of entities?

My problem today is this: I have many civilians going around, they are classes stored by an arraylist. The idea is when they see another civilian panic, they'll start to panic and it will spread. ...
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City-region generation

I am currently making a procedural generated map and wanted to add regions to the cities indicating their reach, the way I am achieving it currently is by expanding outwards from the city center until ...
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1answer
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How to force a line break before the last word of a line reach the edge?

I'm printing a sliding text by adding each letter after a short period of time. My problem is that when the text multilines, the last word of a line starts on the current line and jumps to the next ...
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1answer
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Finding which tiles are intersected by a line, without looping through all of them or skipping any

I've been staring at this problem for a few days now. I rigged up this graphic to help me visualise the issue: (from the graph, we know that the line intersects [1, 1], [1, 2], [2, 2], [2, 3], ending ...
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Implementing AI to hide behind obstacles

I am developing an AI simulation of predator and prey. I would like to simulate the AI hiding behind obstacles, if it is being chased. But I am still trying to figure out the best way to implement ...
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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 ...
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1answer
353 views

Tiling perlin noise seamlessly, but without repeating to generate an infinite 3D world

I have been working on a 3D game in java using LWJGL for a while now. I am trying to make procedurally generated infinite 3D terrain that is generated around the player. So far I have: 3D terrain ...
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2answers
608 views

Handling commands or events that wait for an action to be completed afterwards

Say you have two events: Action1 and Action2. When you receive Action1, you want to store some arbitrary data to be used the next time Action2 rolls around. Optimally, Action1 is normally a command ...
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Framerate is affecting speed of object

I'm experimenting with building a game engine from scratch in Java, and I have a couple questions. My main game loop looks like this: int FPS = 60; while(isRunning){ /* ...
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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" ...
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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 ...
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Java collections and managing simultaneous operations / concurrency (java.util.ConcurrentModificationException)

Ok, so i have created my first "game" and it uses a lot of java's collections. for example, i have a bunch of monsters in a HashSet which sometimes gives me the fabled ...
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3answers
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A more sophisticated ball-paddle collision algorithm for Breakout?

I have a simple breakout game I'm working on. The collision code is solid; things bounce as they should and don't pass through things or do other funkiness, but the reflection is a bit simplistic. As ...
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2answers
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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 ...
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5answers
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Killer Game Programming [Java 3D] outdated?

I'm thinking of picking up the book Killer Game Programming by Andrew Davidson, but its pretty old now. I know Java, and I've been messing with jMonkeyEngine for a few days now, but I'm curious to see ...
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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 ...
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3answers
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A-Star Pathfinding Not Giving Shortest Path

I'm attempting to implement the A* pathfinding algorithm in Java. I thought it was working well, but then I found instances where it doesn't follow the shortest path Green = start, red = target, ...
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Why do my images take 200 MB of RAM when they are ~20KB on disk?

I am creating an Android game using libGDX. When I load my nine images it takes 200 MB of RAM. But the images are 10 to 17 KB each. Why the discrepancy? Here is where I create textures from those ...
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Problem to match font size to the screen resolution in libgdx

I'm having problems to show text on my game at same size on different screens, and I did a simple test. This test consists to show a text fitting at the screen, I want the text has the same size ...
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1answer
290 views

Why does flipping 1 texture region cause an identical texture region to also be flipped? (libGDX)

Sorry for the bad title. I didn't know how else to explain it. The following is a portion of my code: public class AssetLoader { public static TextureAtlas spriteSheet; public static ...
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2answers
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Disadvantages of using multiple versions of OpenGL in LWJGL?

So, I'm trying to figure out LWJGL, and my goal is to use OpenGL 3.2 (because pretty shaders are pretty). But in every tutorial I can find for LWJGL, they import a bunch of different OpenGL versions ...
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4answers
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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 ...
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3answers
483 views

Common ways to keep up with character state in a 2D game?

I am currently developing a 2D Blockdude clone for learning purposes and am wondering about storing character state in the game. For example, the character can be facing either right or left. What are ...
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3answers
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Java enum pairs / “subenum” or what exactly?

I have an RPG-style Item class and I stored the type of the item in enum (itemType.sword). I want to store subtype too (itemSubtype.long), but I want to express the relation between two data type ...
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Java and Steam JVM deployment

I am currently considering my options for game development and deploying to Steam Greenlight. I really like Java with libGDX, especially for its cross platform Android potential, and I understand that ...
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487 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 ...
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4answers
781 views

Profiling server side game loop in java

I am looking for tips to profile the server side game loop of a Java program for CPU usage. I tried to use the TPTP plugin for Eclipse so far. The problem I am having is that it is really slow. For ...
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1answer
554 views

2D Polygon Triangulation

I am creating a game engine using the JBox2D physics engine. It only allows you to create polygon fixtures up to 8 vertices, To create a body with more than 8 vertices, you need to create multiple ...
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1answer
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SQLite in libGDX

Does anyone have an example of how I can use SQLite in libGDX? I have a class in my original Android code that allowed me to easily access a database but I can't seem to find anything equivalent to ...
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How to loop over a part of an ogg vorbis stream?

I'm successfully streaming ogg vorbis data to openAL with the Java library JOrbis, but now I want to loop over a part of this stream, e.g from 30" to 1'30". I thought that at the end of the loop, I ...
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692 views

An odd performance problem rendering a simple scene (less than 14k vertices) in OpenGL using two vbos with LWJGL

Problem I have been having a strange degrading performance issue rendering a simple scene containing two "chunks" of 4x4x4 cubes each. Video of problem This is a screen capture showing my console ...
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1answer
999 views

Minecraft Mod portable torch/lantern

I have just started making a mod for minecraft, I learned how to make items and import custom png's and have gotten all of that to work. I have been searching around the code trying to find a way to ...
6
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1answer
875 views

Is Java AWT suitable for 2d game rendering?

[Reposting this question from stackoverflow, as it was pointed out that it fits better here.] I'm currently porting my 2D game engine to Java. I looked at some of the game libraries pointed at here ...
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1answer
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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 ...
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2answers
366 views

Where can I find some beginners to learn and work with? [closed]

I am very new to game programming. I am currently studying Java (Android mainly) and I know what it takes to make a game, as well as how to render it via OpenGL. Finding some others at nearly my level ...
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1answer
780 views

For 2D tiled maps is all object and NPC data loaded into memory when the map is loaded?

I'm creating a text RPG in Java, but I think this applies for a GUI as well with regard to the data structure. Each Level is a tiled map. Each Tile object has an (X,Y) coordinate, and references to ...
6
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1answer
116 views

Minimum number of moves algorithm in Java

I'm looking to implement the minimum number of moves algorithm for the java game I'm developing but I can't quite figure it out. Here's an example picture: There are also some specifications ...
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2answers
894 views

Are there any game engines in C# or Java that are cross-platform and support multitouch input? [closed]

I'm looking for game engines (particularly 2D) that can run/create games for Windows, Mac, and Linux, and support multitouch inputs and gestures. I'm able to find many that meet the first two ...
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1answer
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How to debug framerate drops with VBOs, OpenGL

I'm working on an experimental app to test how VBOs perform when rendering a minecraft-like world. If the performance is better than what I use now I'll update my actual game. Based on what everyone ...
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2answers
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Scalability of multi-threading in game server

What is a reasonable number of threads for a simple 2D mmo in Java? Is it reasonable to have two threads per connection, one for the input stream and one for the output stream? The reason I ask is ...
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1answer
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Method of terrain in a 3d RPG

I am working on a RPG using the JMonkey engine. While I was conceptualizing the map, I realized I would have a problem with the terrain. My problem is this: I want to have a click to move interface, ...
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5answers
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Do I really need to “learn” C# for XNA if I know Java?

I want to start developing in XNA. As of now, I do not know C#, but I would consider myself "good" at Java. I have looked at some C# code and it looks almost identical to Java. After looking at Java ...
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3answers
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Is this really the reason for smoother movement?

Actually i'm watching a tutorial series on youtube about 2D Game programming in Java. My question is about the player-movement. The first version: public void keyPressed(KeyEvent e) { ...