LibGDX is a cross-platform Java game development framework based on OpenGL (ES) that works on Windows, Linux, Mac OS X, Android, iOS and your WebGL enabled browser.

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17
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3answers
21k views

Resolution Independence in libGDX

How do I make my libGDX game resolution/density independent? Is there a way to specify image sizes as "absolute" regardless of the underlying density? I'm making a very simple kids game; just a bunch ...
5
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5answers
20k views

How do I destroy a Box2D body on contact without getting an IsLocked assertion error?

I get this error when attempting to remove a body from the world: java: /var/lib/hudson/jobs/libgdx/workspace/trunk/gdx/jni/Box2D/Dynamics/b2World.cpp:134: void b2World::DestroyBody(b2Body*): ...
3
votes
2answers
11k views

How can I convert a tilemap to a Box2D world?

I want to use Box2D physics and lighting with a .tmx map. How can I "convert" a tilemap to Box2D world? My basic idea is to go through the tiles on the map and create an object for them in Box2D. I'm ...
5
votes
4answers
8k 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, ...
8
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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 ...
6
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1answer
6k views

Why is my sprite displayed offset from its Box2D body?

I found out about this using a debug renderer. When the game starts, everything is in order. But when a collision happens, the sprite's rotation is way larger than its body. The sprite and body match ...
2
votes
1answer
3k views

Movement and rotation of bodies in top down game

We are developing a 2D top down game with libgdx using the included box2d as physics engine. We don't want our bodies to accelerate but to instantly move with the wanted velocity. The bodies are ...
7
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3answers
740 views

How can I check if a player-drawn line follows a path?

I want to draw an invisible path that the user must follow. I've stored that path as points. When a player draws a line, how can I test if it follows the path I've stored? Here's an example for ...
2
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1answer
1k views

LibGDX Cross Platform Networking

Backstory: I've been developing a game with LibGDX for the past two years, and I've seen it refactored more times than I remember. I jumped on the iOS iKVM port as soon as it was released. But I've ...
0
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2answers
456 views

Efficient way to check collision with potentially hundreds of objects [duplicate]

I am trying to make a top down shooter that could potentially have hundreds of objects at once at one point. I need to check collision with projectiles, walls, and enemies. I am currently using ...
3
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4answers
3k 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 ...
6
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1answer
5k views

How to match font size with screen resolution?

So I'm working on a game using LibGDX, and I have a problem. To make my game fit most resolutions, I created a base asset for each aspect ratio, for example, a main menu background image, I made it ...
3
votes
2answers
3k views

How do you create fnt (angelcode format) files from existing bitmaps?

I often gets the same problem: Someones creates a nice bitmap font for me in form of a sheet nicely formated into a png, like this: ...and i need to create the angelcode .fnt atlas for using it (...
2
votes
2answers
5k views

LibGDX Swipe Detection Left and Right

I have displayed an image at the center of the screen with libgdx. If I swipe left, the image should move to the left; and, if I swipe right, image should move to the right. Subsequent swipes to the ...
2
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3answers
3k views

How do I change my gravity and jumping logic to put the character at a specific height at a specific point in time?

I'm making a 2D platformer on Android using libGDX. One thing I've had a problem with recently is gravity and jumping. I found a few tutorials on the internet and was able to come up with this... ...
7
votes
2answers
2k views

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 ...
6
votes
5answers
10k views

Why do I get this file loading exception when trying to draw sprites with libgdx?

I'm having trouble with the "Drawing Images" section on the libgdx tutorial. I set up the documents completely and I typed the code as follows: public class Game implements ApplicationListener { ...
4
votes
2answers
427 views

Why are my Box2D wheels slipping on ground?

I have a car, set up in Box2D as a rectangle connected with two wheels using WheelJoints: The wheels are defined as follows: FixtureDef wheelFixtureDef = new FixtureDef(); wheelFixtureDef....
2
votes
3answers
12k views

Camera Coordinate To Screen Coordinate

I want to convert the camera coordinate to screen coordinate. I have asked this question because my camera is 48m wide and 32m high but my screen is 480x320 pixels. So whatever collision point I get ...
6
votes
3answers
1k views

Understanding how to create/use textures for games when limited by power of two sizes

I have some questions about the creating graphics for a game. As an example. I want to create a motorbike. (1pixel = 1centimeter) So my motorbike will have 200 width and 150 height. (200x150) But the ...
5
votes
1answer
3k views

ShapeRenderer efficiency on games

I want to draw a rectangle box to use as a text background for a visual novel library I'm writing, I wanted some flexibility of color and transparency and the ShapeRenderer class seems to fit the need ...
4
votes
1answer
280 views

GLSL 2D Silhouette

I'm trying to render a silhouette of any entity behind foreground objects to indicate their position to the player. Here's an example of what I want to achieve, from Hyper Light Drifter: From what ...
4
votes
1answer
2k views

Problem Implementing Texture on Libgdx Mesh of Randomized Terrain

I'm having problems understanding how to apply a texture to a non-rectangular object. The following code creates textures such as this: from the debug renderer I think I've got the physical shape ...
4
votes
1answer
431 views

Why is libGDX's HexagonalTiledMapRenderer adding extra space?

Why are there large spaces between the hexes when rendered by HexagonalTiledMapRenderer? The tiles ARE black bordered, but that doesn't account for all the extra space. I was also able to get them ...
3
votes
3answers
1k views

2D - Smooth lighting with shadows for a tile-based game

for the last week or so I have been completely stuck on trying to implement efficient lighting. I've been researching and experimenting and I've looked everywhere that I have been capable of finding, ...
2
votes
1answer
837 views

Match-3 algorithm to fill empty space left from removing matches

I am currently creating a match 3 game. I am at the point where I have objects dropping down in the column when only one item is removed. So if an item is removed, the above item moves into its old ...
2
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1answer
2k 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
1answer
812 views

Libgdx understanding screen size

I'm trying to create my own jumper type game where the player moves up through an infinite y value. The problem I am having is getting the screen size to match up with the android screen. viewport =...
2
votes
1answer
806 views

Collision detection in libgdx

I am currently writing a little zelda like game and have a little bit of a problem with collision detection. It works but the the character stands to far away from the object. Here is my player ...
2
votes
5answers
3k views

How to Make Objects Fall Faster in a Physics Simulation

I used the collision physics (i.e. Box2d, Physics Body Editor) and implemented onto the java code. I'm trying to make the fall speed higher according to the examples: It falls slower if light object ...
2
votes
2answers
2k views

Sprite draw-order in libgdx

From other frameworks I know methods for easy ordering sprites within a spritebatch (to determine if a sprite has to be drawn in front or behind another sprite). For example in MonoGame/XNA this is ...
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2answers
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Libgdx actor bounds are wrong

The Actor's boundaries are not centered at the ButtonText but I used the setBounds() method. The higher the Y position is, the less centered is the boundary. The weird thing is that i only created and ...
0
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0answers
251 views

Sprites not being rendered on screen change - Android Libgdx

In my game over screen for my Libgdx Android game I've the following code which starts a new game upon a screen touch. if(Gdx.input.isTouched()) { ScreenManager.setScreen(new ...
4
votes
3answers
894 views

Libgdx body passing through block then fall on it

I'm using libgdx and its physic engine Box2d. My question is : how could I make my box2d body go through a block , ignore the first collison than make the block active so the ball can fall onto it. A ...
4
votes
1answer
5k views

When to use ShapeRenderer & SpriteBatch in libGdx?

As a beginner(in GdxLib+Android), i found that for rendering particular screen, we can render that using both ways then when to use specific ones? & What is the best option for Updating the ...
3
votes
1answer
8k views

How do I properly implement zooming in my game?

I'm trying to implement a zoom feature but I have a problem. I am zooming in and out a camera with a pinch gesture, I update the camera each time in the render, but my sprites keep their original ...
3
votes
1answer
1k views

Setting uniform value of a vertex shader for different sprites in a SpriteBatch

I'm using libGDX and currently have a simple shader that does a passthrough, except for randomly shifting the vertex positions. This shift is a vec2 uniform that I set within my code's render() loop. ...
3
votes
2answers
1k views

LibGDX: Easy way to draw partial sprites

I am surely overlooking something, but is there an easy to draw for example only half a sprite in LibGDX? I originally thought I could do this with setBounds() but this distorts the sprite.
2
votes
1answer
4k views

Repeat texture in a scrolling game

The bottom region of the screen is filled by a repeated texture: grassTexture = new Texture(Gdx.files.internal("images/grass.png")); grassTexture.setWrap(TextureWrap.Repeat, TextureWrap.Repeat); ...
2
votes
1answer
239 views

Drawing textures off screen optimization required?

I recently started using LibGDX and I am wondering if I have to optimize my code when drawing textures/sprites off-screen, just like I used to do with XNA. My biggest concern here is specifically ...
2
votes
1answer
306 views

How do I detect a line collison in LIBGDX?

I am drawing a continuous line using Pixmap. I want to check for a collision / intersection of my line with the already drawn line.
2
votes
1answer
5k views

Convert Screen coords to World Coords LIBGDX

I'm working on a tile based platformer game in libgdx. I'm having trouble getting the actual touch input coordinates when the aspect ratio of device is different from the virtual fixed aspect ratio ...
2
votes
1answer
114 views

Screen not rendering after restarting game

Game works fine on the initial launch on Android, but after that restarting game does not render the graphics on the screen properly. It is a copy of the question Sprites not being rendered on ...
1
vote
2answers
300 views

How to render rounded shape perfectly?

I'm having issues rendering rounded shape figures. I have a Texture with different images in it and I get this whale figure from it with TextureRegion but the stroke of it looks pixelated. The ...
1
vote
1answer
991 views

Input events not working simultaneously on android devices in libgdx

I am making a simple platform game in Libgdx... in which I have made the player to move left, move right and jump. The code works fine on Desktop but on Android devices, Jump is not fired when the ...
1
vote
1answer
223 views

Why is there a huge update-delay in my client/server code?

I'm working on my Java game with Libgdx and having trouble with the network code. I can create a server, make multiple clients connect to it, but there is a huge delay between the player's input and ...
1
vote
1answer
143 views

libgdx FollowPath proper usage

I'm developing top-down rpg game and got some problems using https://libgdx.badlogicgames.com/gdx-ai/docs/com/badlogic/gdx/ai/steer/behaviors/FollowPath.html I have a path (picture 1), in this case 2 ...
1
vote
1answer
280 views

LibGdx Sound start to give an error after loading GameScreen multiple times

I have a LibGdx game, where the user taps on the screen, and a Sound will play. When the user taps on the screen, a texture will "fire" another texture as a missile, and can hit a target, when this ...
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vote
3answers
1k 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. @...
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2answers
83 views

What is the velocity of a translating projectile in 2D?

What I'm trying to do. So I want to have a projectile that starts at point (x1, y1) and head in the direction of my mouse say point (x2, y2). To clarify I'm pretty sure it's a vector but I don't ...