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Why is my create() Method Not Recognizing a Global Variable? - Java LibGDX

I have global variables called:
private int currentLevel;
private int mapHeight;
I have a constructor for my game, where currentLevel = level entered when setScreen() method is called:
public ElevatorLevel(Game g, int level)
{
super(g, level);
currentLevel = level;
}
In my create() method, I set mapHeight to 750 * currentLevel (which starts as one), however when I try to spawn in the blades as seen below, they spawn between -200 and 300. This is because the program is not recognizing currentLevel (I am assuming), so it is multiplying it by nothing, resulting with -200.
public void create()
{
world = new World(new Vector2(0, -9.8f), true);
timeElapsed = 0;
mapHeight = 750 * currentLevel;
blade = new PhysicsActor();
blade.storeAnimation( "", exTex );
blade.setOriginCenter();
blade.circularBoundary();
blade.setMaxSpeed(50);
blade.setDeceleration(50);
bladesList = new ArrayList<PhysicsActor>();
for (int i = 0; i < 3 ; i++)
{
blades = blade.clone();
float xCoord = randomFloatGenerator(440, 20);
float yCoord = randomFloatGenerator(mapHeight - 200, 300);
blades.setPosition(xCoord, yCoord);
mainStage.addActor(blades);
bladesList.add(blades);
}
I also have a Label in my update(float dt) method that is set to:
timeLabel.setText("Level: " + currentLevel);
As seen in the image above, currentLevel is recognized by the label, but not by mapHeight in create().
How do I get currentLevel to be recognized by the create() method?

Below is the standart portrait app code that i use almost in every libgdx project. I never use create method. Instead I use constructor, this code is the most bugfree one that i could have found.
GAME OR MENU SCREEN:
public class TutorialScreen implements Screen {
private OrthographicCamera camera;
public static final float WORLD_HEIGHT = 240;
public static final float WORLD_WIDTH = 135;
private Viewport viewport;
private Stage stage;
private EntryPoint game;
private AdsController adsController;
public TutorialScreen(final EntryPoint game, final AdsController adsController){
this.adsController = adsController;
this.game = game;
adsController.hideBannerAd();
float aspectRatio = (float) (Gdx.graphics.getHeight() / Gdx.graphics.getWidth());
camera = new OrthographicCamera(aspectRatio * WORLD_WIDTH, WORLD_HEIGHT);
camera.setToOrtho(false);
viewport = new FitViewport(WORLD_WIDTH , WORLD_HEIGHT,camera );
stage = new Stage(viewport, game.batch);
}
#Override
public void show() {
}
#Override
public void render(float delta) {
stage.draw();
stage.act();
}
#Override
public void resize(int width, int height) {
}
#Override
public void pause() {
}
#Override
public void resume() {
}
#Override
public void hide() {
}
#Override
public void dispose() {
}
}
ENTRY POINT THAT YOUR APP WILL OPEN FIRST:
package some.package;
public class EntryPoint extends Game {
SpriteBatch batch;
final AdsController adsController;
public EntryPoint(final AdsController adsController ){
this.adsController = adsController; //Interface for admob
}
#Override
public void create () {
batch = new SpriteBatch();
this.setScreen(new YourScreenClass(this,adsController)); //Above is tutorial so this would be new TutorialScreen(this,adsController)
}
#Override
public void render () {
Gdx.gl.glClearColor(0, 0, 0, 1);
Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT);
batch.begin();
batch.end();
super.render();
}
#Override
public void dispose () {
batch.dispose();
}
}
Might have missed some curly brackets or ";" but you get the idea. This way you would not encounter any reference issues.

Java libGDX Game - Animation doesn't flip

I have a animation which i want to flip to the left if key LEFT is pressed, but it doesnt stay flipped. It only flips like 1 frame then turns back again.
Here is my GameScreen where i draw everything:
public class GameScreen extends ScreenManager{
//For the view of the game and the rendering
private SpriteBatch batch;
private OrthographicCamera cam;
//DEBUG
private Box2DDebugRenderer b2dr;
//World, Player and so on
private GameWorld world;
private Player player;
private Ground ground;
//player animations
private TextureRegion currFrame;
public static float w, h;
public GameScreen(Game game) {
super(game);
//vars
w = Gdx.graphics.getWidth();
h = Gdx.graphics.getHeight();
//view and rendering
batch = new SpriteBatch();
cam = new OrthographicCamera();
cam.setToOrtho(false, w/2, h/2);
//debug
b2dr = new Box2DDebugRenderer();
//world, bodies ...
world = new GameWorld();
player = new Player(world);
ground = new Ground(world);
}
#Override
public void pause() {
}
#Override
public void show() {
}
#Override
public void render(float delta) {
//clearing the screen
Gdx.gl.glClearColor(0, 0, 0, 1);
Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT);
//updating
update(Gdx.graphics.getDeltaTime());
player.stateTime += Gdx.graphics.getDeltaTime();
//render
batch.setProjectionMatrix(cam.combined);
currFrame = Player.anim.getKeyFrame(Player.stateTime, true);
batch.begin();
batch.draw(currFrame, Player.body.getPosition().x * PPM - 64, Player.getBody().getPosition().y * PPM- 72);
batch.end();
//debug
b2dr.render(GameWorld.getWorld(), cam.combined.scl(PPM));
}
#Override
public void resize(int width, int height) {
}
#Override
public void hide() {
}
#Override
public void dispose() {
}
#Override
public void onKlick(float delta) {
}
public void update(float delta){
world.update(delta);
updateCam(delta);
Player.keyInput(delta);
System.out.println("X-POS" + Player.getBody().getPosition().x);
System.out.println("Y-POS" + Player.getBody().getPosition().y);
}
public void updateCam(float delta){
Vector3 pos = cam.position;
pos.x = Player.getBody().getPosition().x * PPM;
pos.y = Player.getBody().getPosition().y * PPM;
cam.position.set(pos);
cam.update();
}
}
and this is the Player class where the animation is:
public class Player {
public static Body body;
public static BodyDef def;
private FixtureDef fd;
//textures
public static Texture texture;
public static Sprite sprite;
public static TextureRegion[][] region;
public static TextureRegion[] idle;
public static Animation<TextureRegion> anim;
public static float stateTime;
//set form
private PolygonShape shape;
private GameScreen gs;
public Player(GameWorld world){
texture = new Texture(Gdx.files.internal("player/char_animation_standing.png"));
region = TextureRegion.split(texture, texture.getWidth() / 3, texture.getHeight() / 2);
idle = new TextureRegion[6];
int index = 0;
for(int i = 0; i < 2; i++){
for(int j = 0; j < 3; j++){
sprite = new Sprite(region[i][j]);
idle[index++] = sprite;
}
}
anim = new Animation<TextureRegion>(1 / 8f, idle);
stateTime = 0f;
def = new BodyDef();
def.fixedRotation = true;
def.position.set(gs.w / 4, gs.h / 4);
def.type = BodyType.DynamicBody;
body = world.getWorld().createBody(def);
shape = new PolygonShape();
shape.setAsBox(32 / 2 / PPM, 64/ 2 / PPM);
fd = new FixtureDef();
fd.shape = shape;
fd.density = 30;
body.createFixture(fd);
shape.dispose();
}
public static Body getBody() {
return body;
}
public static BodyDef getDef() {
return def;
}
public static Texture getTexture() {
return texture;
}
public static void keyInput(float delta){
int horizonForce = 0;
if(Gdx.input.isKeyJustPressed(Input.Keys.UP)){
body.applyLinearImpulse(0, 300f, body.getWorldCenter().x, body.getWorldCenter().y, true);
//body.applyForceToCenter(0, 1200f, true);
System.out.println("PRESSED");
}
if(Gdx.input.isKeyPressed(Input.Keys.LEFT)){
horizonForce -= 1;
sprite.flip(!sprite.isFlipX(), sprite.isFlipY());
}
if(Gdx.input.isKeyPressed(Input.Keys.RIGHT)){
horizonForce += 1;
}
body.setLinearVelocity(horizonForce * 20, body.getLinearVelocity().y);
}
}
thank you in advance and any answer is appreciated :D

Your sprite variable contain only one frame at the time of pressing left key. So, it flip that current sprite of your animation frame.
To solve the Problem you have to flip all the animation frame on pressing the left key.

You're only flipping last frame of Animation by sprite reference, You need to flip all frames of your Animation anim. You can flip in this way :
if(keycode== Input.Keys.RIGHT) {
for (TextureRegion textureRegion:anim.getKeyFrames())
if(!textureRegion.isFlipX()) textureRegion.flip(true,false);
}
else if(keycode==Input.Keys.LEFT) {
for (TextureRegion textureRegion:anim.getKeyFrames())
if(textureRegion.isFlipX()) textureRegion.flip(true,false);
}

Libgdx: how to detect if an enemy was touched?

I want to add to the score of my game +1 when an enemy was touched, I tried two methods addListener and touchDown but not worked for me or I didn't use them right.
How can I do that my (enemy object is linked to an userData and Actor classes, I regroup many different sizes for my enemy in an enum class also those enemies move from the top of the screen to bot. How to detect if an enemy was touched?
public class GameStage extends Stage {
// This will be our viewport measurements while working with the debug renderer
private static final int VIEWPORT_WIDTH = 13;
private static final int VIEWPORT_HEIGHT = 20;
private World world;
private Ground ground;
private Enemy enemy;
private final float TIME_STEP = 1 / 300f;
private float accumulator = 0f;
private Rectangle bounds;
private Vector3 touchPoint = new Vector3();;
private int score;
private String yourScoreName;
BitmapFont yourBitmapFontName;
private SpriteBatch batch;
private OrthographicCamera camera;
private Box2DDebugRenderer renderer;
public GameStage() {
world = WorldUtils.createWorld();
renderer = new Box2DDebugRenderer();
Gdx.input.setInputProcessor(this);
batch = new SpriteBatch();
score = 0;
yourScoreName = "score: 0";
yourBitmapFontName = new BitmapFont();
setUpWorld();
setUpCamera();
}
public void setUpWorld(){
world = WorldUtils.createWorld();
setUpGround();
createEnemy();
}
private void setUpGround(){
ground = new Ground (WorldUtils.createGround(world));
addActor(ground);
}
private void createEnemy() {
enemy = new Enemy(WorldUtils.createEnemy(world));
// (1) *****using addListener method
enemy.addListener(new InputListener()
{
#Override
public boolean touchDown(InputEvent event, float x, float y,
int pointer, int button)
{
score++;
yourScoreName = "score: " + score;
return true;
}
});
/*enemy.addListener(new ClickListener() {
public void clicked() {
world.destroyBody(enemy.getBody());
}});*/
//bounds = new Rectangle(enemy.getX(), enemy.getY(), enemy.getWidth(), enemy.getHeight());
addActor(enemy);
}
private void setUpCamera() {
camera = new OrthographicCamera(VIEWPORT_WIDTH, VIEWPORT_HEIGHT);
camera.position.set(camera.viewportWidth / 2, camera.viewportHeight / 2, 0f);
camera.update();
}
#Override
public void act(float delta) {
super.act(delta);
checkEnemy();
// Fixed timestep
accumulator += delta;
while (accumulator >= delta) {
world.step(TIME_STEP, 6, 2);
accumulator -= TIME_STEP;
}
//TODO: Implement interpolation
}
private void checkEnemy(){
final Body body = enemy.getBody();
UserData userData = enemy.getUserData();
bounds = new Rectangle(enemy.getBody().getPosition().x, enemy.getBody().getPosition().y, enemy.getUserData().getWidth(), enemy.getUserData().getHeight());
// bounds = new Rectangle(body.getPosition().x, body.getPosition().y,userData.getWidth() ,userData.getHeight());
if (!BodyUtils.enemyInBounds(body,userData)){
world.destroyBody(body);
createEnemy();}
}
public World getWorld(){
return world;
}
// (2) ****using TouchDown method
#Override
public boolean touchDown(int x, int y, int pointer, int button) {
// Need to get the actual coordinates
translateScreenToWorldCoordinates(x, y);
// score++;
// yourScoreName = "score: " + score;
if(enemyTouched(touchPoint.x,touchPoint.y)){
// world.destroyBody(enemy.getBody());
score++;
yourScoreName = "score: " + score;
}
return super.touchDown(x, y, pointer, button);
}
private boolean enemyTouched(float x, float y) {
return bounds.contains(x, y);
}
private void translateScreenToWorldCoordinates(int x, int y) {
getCamera().unproject(touchPoint.set(x, y, 0));
}
#Override
public void draw() {
super.draw();
batch.begin();
yourBitmapFontName.setColor(1.0f, 1.0f, 1.0f, 1.0f);
yourBitmapFontName.draw(batch, yourScoreName, 25, 100);
batch.end();
enemy.setBounds(enemy.getBody().getPosition().x,enemy.getBody().getPosition().y,enemy.getUserData().getWidth(),enemy.getUserData().getHeight());
renderer.render(world, camera.combined);
}
}
A screen from my game:

It should work the way you did it (with the addListener() method). But you have to set the correct bounds of the actor (width, height, position): actor.setBounds(x, y, width, height). I would use the body to get these values. You can also use a ClickListener instead of the InputListener.

mirrored against x axis movement

I am trying to implement movement to a point, where mouse was clicked.
But I have a problem with mirrored behaviour agains X axis.
When I click on top -> it moves to the bottom, when I click on bottom -> it moves to the top.
Here is for example original position
I clicked on the screen in position with red cross.
But it moves down (as arrow showed).
What's the problem? It seems something with movement vector I presume.
public class Player {
private static final float PLAYER_CIRCLE_RADIUS = 24f;
private static final float MOVEMENT_SPEED = 200f;
private final Circle playerCircle;
private Vector2 direction = new Vector2();
private Vector2 position;
private Vector2 velocity = new Vector2();
private Vector2 movement = new Vector2();
private Vector2 mouseClick = new Vector2();
public Player(float x, float y) {
position = new Vector2(x, y);
playerCircle = new Circle(x, y, PLAYER_CIRCLE_RADIUS);
}
public void draw(ShapeRenderer shapeRenderer) {
shapeRenderer.circle(position.x, position.y, playerCircle.radius);
}
public void update(float delta) {
movement.set(velocity).scl(delta);
if (position.dst2(mouseClick) > movement.len2()) { position.add(movement); }
else { position.set(mouseClick); }
}
public void setDirection(float x, float y) {
mouseClick.set(x, y);
direction.set(mouseClick).sub(position).nor();
velocity.set(direction).scl(MOVEMENT_SPEED);
}
public Vector2 getDirection() {
return direction;
}
public Circle getPlayerCircle() {
return playerCircle;
}
public Vector2 getMouseClick() {
return mouseClick;
}
}
public class GameScreen extends ScreenAdapter {
private static final float WORLD_WIDTH = 640;
private static final float WORLD_HEIGHT = 480;
private ShapeRenderer shapeRenderer;
private Viewport viewport;
private Camera camera;
private Player player;
private Destination dest;
#Override
public void render(float delta) {
clearScreen();
update(delta);
shapeRenderer.setProjectionMatrix(camera.projection);
shapeRenderer.setTransformMatrix(camera.view);
shapeRenderer.begin(ShapeRenderer.ShapeType.Line);
dest.draw(shapeRenderer);
player.draw(shapeRenderer);
shapeRenderer.end();
}
#Override
public void resize(int width, int height) {
viewport.update(width, height);
}
#Override
public void show() {
camera = new OrthographicCamera();
camera.position.set(WORLD_WIDTH / 2, WORLD_HEIGHT / 2, 0);
viewport = new FitViewport(WORLD_WIDTH, WORLD_HEIGHT, camera);
shapeRenderer = new ShapeRenderer();
player = new Player(WORLD_WIDTH / 2, WORLD_HEIGHT / 2);
dest = new Destination();
Gdx.input.setInputProcessor(new InputAdapter() {
#Override
public boolean touchDown(int screenX, int screenY, int pointer, int button) {
dest.setPosition(screenX, screenY);
camera.unproject(new Vector3(screenX, screenY, 0));
player.setDirection(screenX, screenY);
return true;
}
});
}
private void clearScreen() {
Gdx.gl.glClearColor(Color.BLACK.r, Color.BLACK.g, Color.BLACK.b, Color.BLACK.a);
Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT);
}
private void update(float delta) {
player.update(delta);
}
}

What you describe is actually mirrored on the Y-Axis.
The reason for this behaviour is most likely that your drawing matrix is set in such a way that the origin is in the bottom-left corner with the Y-Axis pointing up, but gui's have their origin at the top-left corner with the Y-Axis pointing down. So when you get your mouse position you should do something like:
actualPosY = screenHeight - mousePosY
This effectively transforms your mouse position to your drawing space.

Centering an animation [libGDX]

I have the following class:
public class AnimationDemo implements ApplicationListener {
private SpriteBatch batch;
private TextureAtlas textureAtlas;
private Animation animation;
private float elapsedTime = 0;
private OrthographicCamera camera;
private int width;
private int height;
private int texturewidth;
private int textureheight;
#Override
public void create() {
width = Gdx.graphics.getWidth();
height = Gdx.graphics.getHeight();
camera = new OrthographicCamera(width, height);
camera.position.set(width / 2, height / 2, 0);
camera.update();
batch = new SpriteBatch();
textureAtlas = new TextureAtlas(Gdx.files.internal("data/packone.atlas"));
textureAtlas.getRegions().sort(new Comparator<TextureAtlas.AtlasRegion>() {
#Override
public int compare(TextureAtlas.AtlasRegion o1, TextureAtlas.AtlasRegion o2) {
return Integer.parseInt(o1.name) > Integer.parseInt(o2.name) ? 1 : -1;
}
});
animation = new Animation(1 / 15f, textureAtlas.getRegions());
}
#Override
public void dispose() {
batch.dispose();
textureAtlas.dispose();
}
#Override
public void render() {
Gdx.gl.glClearColor(0, 0, 0, 1);
Gdx.gl.glClear(GL30.GL_COLOR_BUFFER_BIT);
batch.begin();
elapsedTime += Gdx.graphics.getDeltaTime();
batch.draw(animation.getKeyFrame(elapsedTime, true), 0, 0);
batch.end();
}
#Override
public void resize(int width, int height) {
}
#Override
public void pause() {
}
#Override
public void resume() {
}
}
In the above I am using the Animation class to simply draw from a texture atlas. I am following an example from another SO question which is here but the co-ordinates don't fit my equation. How should I set these:
private int texturewidth;
private int textureheight;
Any help would be great :)

you need to care about proper offset - the origin is always at the left bottom corner and that is why you need to subtract half of width and height when drawing.
In a nutshell it should be like:
TextureRegion region = animation.getKeyFrame(elapsedTime, true);
batch.draw(region, 0 - (region.getRegionWidth()/2f), 0 - (region.getRegionHeight()/2f));