Java – How do I zoom in and out of the stage in libgdx Scene2d?

I’m making a 2d game using libgdx and adding hexagonal actors to a group and then adding them to the stage. For normal cameras, you can use camera.zoom in and out in the rendering method, while using camera.translate to travel the world.

I’ve been using stage.getCamera() to get the

camera used on the stage, and I can still call stage.getcamera().translate but without the stage.getCamera().zoom option.

Here is my code :

//import statements

public class HexGame implements ApplicationListener{

private Stage stage;

private Texture hexTexture;
private Group hexGroup;

private int screenWidth;
private int screenHeight;

@Override
public void create() {

hexTexture = new Texture(Gdx.files.internal("hex.png"));

screenHeight = Gdx.graphics.getHeight();
    screenWidth = Gdx.graphics.getWidth();

stage = new Stage(new ScreenViewport());

hexGroup = new HexGroup(screenWidth,screenHeight,hexTexture);

stage.addActor(hexGroup);
}

@Override
public void dispose() {
    stage.dispose();
    hexTexture.dispose();
}

@Override
public void render() {
    Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT);
    stage.act(Gdx.graphics.getDeltaTime());
    stage.draw();

handleInput();
    stage.getCamera().update();

}

private void handleInput() {

if (Gdx.input.isKeyPressed(Input.Keys.LEFT)) {
        stage.getCamera().translate(-3, 0, 0);
    }
    if (Gdx.input.isKeyPressed(Input.Keys.RIGHT)) {
        stage.getCamera().translate(3, 0, 0);
    }
    if (Gdx.input.isKeyPressed(Input.Keys.DOWN)) {
        stage.getCamera().translate(0, -3, 0);
    }
    if (Gdx.input.isKeyPressed(Input.Keys.UP)) {
        stage.getCamera().translate(0, 3, 0);
    }

This is the part that doesn't work
    /*
    if (Gdx.input.isKeyPressed(Input.Keys.Z)) {
        stage.getCamera().zoom += 0.02;
    }
    */

}

@Override
public void resize(int width, int height) {
    stage.getViewport().update(width, height);
}

@Override
public void pause() {
}

@Override
public void resume() {
}

}

Thanks for any help, please let me know if I have any other issues with my code, I’m new to libgdx. Thanks

Scaling is available in the OrthographicCamera

class, which by default creates an OrthographicCamera

/** Creates a stage with a {@link ScalingViewport} set to {@link Scaling#stretch}. The stage will use its own {@link Batch}
     * which will be disposed when the stage is disposed. */
    public Stage () {
        this(new ScalingViewport(Scaling.stretch, Gdx.graphics.getWidth(), Gdx.graphics.getHeight(), new OrthographicCamera()),
            new SpriteBatch());
        ownsBatch = true;
    }

Therefore, you need to convert the camera to OrthographicCamera:

((OrthographicCamera)stage.getCamera()).zoom += 0.02f;