How to make the camera follow the player? - libgdx

Question

I'm making a game in libgdx which includes the player being able to move vertically beyond the set screen size.
As for my question, if I have the screen size set at a certain width and height, what is required to make the actual game world larger for the camera to follow the player?
This is of course my targeted screen size in the Main game class:
public static final int WIDTH = 480, HEIGHT = 800;
Below that I currently have :
public static final int GameHeight = 3200;
GameHeight is the value I test for whether the player is going out of bounds.
Here is the problem. With this code, the player is centered on the screen, and moves horizontally, rebounding off the screen bounds (As it would without the camera, but neglecting the change in y-position)
public GameScreen(){
cam = new OrthographicCamera();
cam.setToOrtho(false, 480, 800);
}
#Override
public void render(float delta) {
// TODO Auto-generated method stub
Gdx.gl.glClearColor(0, 0, 0, 1);
Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT);
cam.position.y = player.getPosition().y;
cam.update();
batch.setProjectionMatrix(cam.combined);
player.update();
player.draw(batch);
}
If I remove:
cam.position.y = player.getPosition().y;
The camera is placed at the bottom of the virtual world and the ball starts at the top (y = 3200) and travels downward. When it reaches y = 800, it shows up as it should.
I've found a lot of examples that indicate in writing that setting the cameras position to the players y position should force the camera to follow the player, whether it's moving up or down, but it either freezes y movement or sets the camera at the bottom the virtual world.
Any help is appreciated, thanks!

Answer 1

I would try doing cam.position.set(player.getPosition().x, player.getPosition().y). This will make the camera follow your player and it should not cause any "freezing."

Answer 2

private val worldTransform = Matrix4()
private val cameraPosition = Vector3()
private val objPosition = Vector3()
private var rot = Quaternion()
private var carTranslation = Vector3(0f, 0f, 0f)
fun focus(obj: BulletObject) {
// worldTransform
obj.entity?.motionState?.getWorldTransform(worldTransform)
// objPosition
worldTransform.getTranslation(objPosition)
obj.entity?.modelInstance?.transform?.getTranslation(carTranslation)
// get rotation
worldTransform.getRotation(rot)
println("rot.angle: ${rot.getAngleAround(Vector3.Y)}")
val rad = Math.toRadians(rot.getAngleAround(Vector3.Y).toDouble())
// pointFromCar
val pointFromCar = Vector2(-3f * sin(rad.toFloat()), -3f * cos(rad.toFloat()));
cameraPosition.set(Vector3(objPosition.x + pointFromCar.x, objPosition.y + 1f, objPosition.z + pointFromCar.y))
// camera set position
camera.position.set(cameraPosition)
camera.lookAt(objPosition)
camera.up.set(Vector3.Y)
camera.update()
}